Section 2 Ligament Injuries

**13**

**Chapter 2**

**Abstract**

**1. Introduction**

Ski Lesions Around the Knee:

*Guillem Navarro Escarp, Oscar Ares Rodriguez,* 

*Ignacio Moya Molinas, Pilar Camacho Carrasco,* 

*Alonso Zumbado Dijeres, Roberto Seijas Vazquez,* 

Ski is a popular sports practiced worldwide although it is considered a high-risk sports with high incidence of injuries. A common place for injuries is the knee, with a wide range from knee sprains to complex ligamentous injuries to fractures. In this chapter, we made a search in PubMed using the words "knee" and "ski." Later, we selected those articles according to the inclusion criteria. When reviewing the literature, we found that the most common place for a ski-related injury is the knee, with knee sprains and ACL lesions being the most common diagnosis in the latter years with a decreasing incidence of tibia fractures. We could also analyze the risk factors different authors have found, for professional athletes and for recreational skiers. In conclusion, the ACL lesion in the skier presents a high incidence, which

Alpine skiing is a very popular sports with an increasing number of participants worldwide although being considered a high-risk sports with a high incidence of injuries in its participants. It is a sports with a great diversity in the profile and level of people practicing it, from amateur skiers to professional athletes with a high

Among the most frequent injuries, there are those affecting the knee joint, with a wide specter of severity: from mild sprains or contusions to serious multiligamen-

The aim of this study is to perform a literature review to assess the more common injuries in alpine skiing, see if there is a change in recent years due to new equipment and attitudes, look for its risk factors, and analyze possible preventive

A Literature Review

*Andrea Sallent, Manuel Llusa Pérez* 

suggests an effort should be made to prevent it.

**Keywords:** knee, ski, ACL, ligament, MCL

number of hours of exposure to injury risk.

measures to reduce the risk of serious injuries.

tary injuries or complex fractures.

*and Andreu Combalia Aleu*

**Chapter 2**

## Ski Lesions Around the Knee: A Literature Review

*Guillem Navarro Escarp, Oscar Ares Rodriguez, Ignacio Moya Molinas, Pilar Camacho Carrasco, Alonso Zumbado Dijeres, Roberto Seijas Vazquez, Andrea Sallent, Manuel Llusa Pérez and Andreu Combalia Aleu*

#### **Abstract**

Ski is a popular sports practiced worldwide although it is considered a high-risk sports with high incidence of injuries. A common place for injuries is the knee, with a wide range from knee sprains to complex ligamentous injuries to fractures. In this chapter, we made a search in PubMed using the words "knee" and "ski." Later, we selected those articles according to the inclusion criteria. When reviewing the literature, we found that the most common place for a ski-related injury is the knee, with knee sprains and ACL lesions being the most common diagnosis in the latter years with a decreasing incidence of tibia fractures. We could also analyze the risk factors different authors have found, for professional athletes and for recreational skiers. In conclusion, the ACL lesion in the skier presents a high incidence, which suggests an effort should be made to prevent it.

**Keywords:** knee, ski, ACL, ligament, MCL

#### **1. Introduction**

Alpine skiing is a very popular sports with an increasing number of participants worldwide although being considered a high-risk sports with a high incidence of injuries in its participants. It is a sports with a great diversity in the profile and level of people practicing it, from amateur skiers to professional athletes with a high number of hours of exposure to injury risk.

Among the most frequent injuries, there are those affecting the knee joint, with a wide specter of severity: from mild sprains or contusions to serious multiligamentary injuries or complex fractures.

The aim of this study is to perform a literature review to assess the more common injuries in alpine skiing, see if there is a change in recent years due to new equipment and attitudes, look for its risk factors, and analyze possible preventive measures to reduce the risk of serious injuries.

#### **2. Epidemiology**

Alpine skiing is the most popular winter sports [1] worldwide. Only in the United States, more than 18 million people 5 years old or older participated in alpine skiing or snowboarding at least in one occasion in the 2011–2012 season [2], and there are about 200 million skiers worldwide [3]. Even more this popularity seems to be increasing all around the world.

Professional skiing is also a popular sports, with 3625 ski races arranged by the International Ski Federation (FIS) in the 2007–2008 season, of those 74 were Alpine Ski World Cup races in which up to 443 athletes participated [4]. Ski racing comprises diverse disciplines from aggressive-turning and highly technical demands like slalom to high speed with big jumps with almost no protective wear like downhill. Besides, alpine ski racing is a popular TV sports, with up to 250 million of TV spectators in 2009 according to FIS data.

It is a well-known fact that skiing is a sports with a high incidence of injuries, some estimate about 2.5–3 injuries per 1000 skier days in amateur practice [3], with head trauma and injuries around the knee being the most frequently reported. Knowing this data one can simply imagine the huge sanitary, social, and economic burden that skier injuries suppose in our societies.

#### **3. Material and methods**

A literature search was made using the PubMed database. We used keywords as ski and knee in order to maximize the number of results. In this first search, we obtained 285 results. We decided to include articles from 1995 to 2018 to be able to compare data published before many technological innovations were introduced with more recent data; this limited the number of articles to 211. All titles and abstracts were analyzed to identify the articles of interest: those investigating about the incidence, types, and risk factors for knee injuries during the practice of alpine skiing in adult population, either amateur or professional.

**15**

*Ski Lesions Around the Knee: A Literature Review DOI: http://dx.doi.org/10.5772/intechopen.83646*

review.

**4. Results**

**4.1 Athlete skiers**

original articles, and 3 reviews.

All the process with its phases is detailed in **Figure 1**.

studies' designs also presented a great variability.

Descriptive and analytical studies were included, and some reviews were taken into account for its particular interest and value. Experimental and laboratory studies were excluded, as well as case reports. We had to discard all articles not written in English and those whose complete text was not possible to obtain for any reason.

Given the reduced number of studies with high-quality evidence in knee injuries

After applying the process explained in the previous point, we had 21 results, 18

Referring to the alpine ski racers' population, Stenroos and Handolin [1] reported no differences in the absolute injury rate in men compared to women, although the mean age of their study is 14 years old, which in our opinion can produce some bias. The most common injury mechanism was the fall down on the same level, with 56% of injuries taking place on giant slalom runs (characterized by higher speed runs) and 31% on slalom runs. About 74% of injuries in this study group required hospitalization. Knee injuries represented the 34.4% of all injuries: 81% were ligamentous injuries being 47% of them anterior cruciate ligament (ACL) injuries (which means the ACL injuries were the 13% of the total). Ligamentous knee injuries were more common in women than in men; in the ACL group, 75% of injured skiers were women. Recovery after an ACL injury took a mean time of 175 days (range 150–180 days) without skiing, and all those patients reported mild or great discomfort in skiing 6 months after the injury. No knee fractures were reported; but 26% of injuries were leg (tibia and fibula) fractures, a surprising high rate when comparing

to literature, probably due to the relative young age of this study population.

Ski Power Test) did not correlate with ACL injury risk.

Similar results were reported by Schmitt et al. [5] in a study in athletes in the Swiss national ski teams. A knee injury rate of 35% was reported, with no differences between men and women; 71% were ACL injuries, of which 26% were isolated ACL injuries and 44% presented an associated injury of a collateral ligament and/or menisci. Their conclusion is that ACL is the most frequent knee injury in competitive alpine skiing. In their objective to describe risk factors for ACL injury, they report a higher risk in slalom runs (with more aggressive and technical turns but at lower speeds) and in athletes with better FIS score and rank, highlighting a higher prevalence of ACL ruptures in the top 30 World Cup skiers. Finally, body mass index, weight, and fitness status (assessed with a specific fitness test: Swiss

In two successive studies, Flørenes et al. [4] and Bere et al. [6] investigated the sex differences in risk injury in World Cup skiers, first for two seasons [4] and then for six seasons [6]. They report a mean absolute injury rate of 36.2 injuries/100 athletes/season with a higher relative injury rate in men (11.3 injuries/1000 runs)

When analyzing all the studies, the first thing that stands out is the big variability between them. We could find studies referring to professional athletes and others to general amateur skiers. We could also find studies done in high-level trauma centers and others done in small ski resort clinics without a physician, with great differences in the diagnostics and clinical information reported. Moreover, the

in alpine skiing, it was deemed that the best methodology was to do a narrative

**Figure 1.** *Chart showing the selection process of our study.*

*Ski Lesions Around the Knee: A Literature Review DOI: http://dx.doi.org/10.5772/intechopen.83646*

Descriptive and analytical studies were included, and some reviews were taken into account for its particular interest and value. Experimental and laboratory studies were excluded, as well as case reports. We had to discard all articles not written in English and those whose complete text was not possible to obtain for any reason. All the process with its phases is detailed in **Figure 1**.

Given the reduced number of studies with high-quality evidence in knee injuries in alpine skiing, it was deemed that the best methodology was to do a narrative review.

#### **4. Results**

*Knee Surgery - Reconstruction and Replacement*

to be increasing all around the world.

spectators in 2009 according to FIS data.

**3. Material and methods**

burden that skier injuries suppose in our societies.

skiing in adult population, either amateur or professional.

Alpine skiing is the most popular winter sports [1] worldwide. Only in the United States, more than 18 million people 5 years old or older participated in alpine skiing or snowboarding at least in one occasion in the 2011–2012 season [2], and there are about 200 million skiers worldwide [3]. Even more this popularity seems

Professional skiing is also a popular sports, with 3625 ski races arranged by the International Ski Federation (FIS) in the 2007–2008 season, of those 74 were Alpine Ski World Cup races in which up to 443 athletes participated [4]. Ski racing comprises diverse disciplines from aggressive-turning and highly technical demands like slalom to high speed with big jumps with almost no protective wear like downhill. Besides, alpine ski racing is a popular TV sports, with up to 250 million of TV

It is a well-known fact that skiing is a sports with a high incidence of injuries, some estimate about 2.5–3 injuries per 1000 skier days in amateur practice [3], with head trauma and injuries around the knee being the most frequently reported. Knowing this data one can simply imagine the huge sanitary, social, and economic

A literature search was made using the PubMed database. We used keywords as ski and knee in order to maximize the number of results. In this first search, we obtained 285 results. We decided to include articles from 1995 to 2018 to be able to compare data published before many technological innovations were introduced with more recent data; this limited the number of articles to 211. All titles and abstracts were analyzed to identify the articles of interest: those investigating about the incidence, types, and risk factors for knee injuries during the practice of alpine

**2. Epidemiology**

**14**

**Figure 1.**

*Chart showing the selection process of our study.*

After applying the process explained in the previous point, we had 21 results, 18 original articles, and 3 reviews.

When analyzing all the studies, the first thing that stands out is the big variability between them. We could find studies referring to professional athletes and others to general amateur skiers. We could also find studies done in high-level trauma centers and others done in small ski resort clinics without a physician, with great differences in the diagnostics and clinical information reported. Moreover, the studies' designs also presented a great variability.

#### **4.1 Athlete skiers**

Referring to the alpine ski racers' population, Stenroos and Handolin [1] reported no differences in the absolute injury rate in men compared to women, although the mean age of their study is 14 years old, which in our opinion can produce some bias. The most common injury mechanism was the fall down on the same level, with 56% of injuries taking place on giant slalom runs (characterized by higher speed runs) and 31% on slalom runs. About 74% of injuries in this study group required hospitalization. Knee injuries represented the 34.4% of all injuries: 81% were ligamentous injuries being 47% of them anterior cruciate ligament (ACL) injuries (which means the ACL injuries were the 13% of the total). Ligamentous knee injuries were more common in women than in men; in the ACL group, 75% of injured skiers were women. Recovery after an ACL injury took a mean time of 175 days (range 150–180 days) without skiing, and all those patients reported mild or great discomfort in skiing 6 months after the injury. No knee fractures were reported; but 26% of injuries were leg (tibia and fibula) fractures, a surprising high rate when comparing to literature, probably due to the relative young age of this study population.

Similar results were reported by Schmitt et al. [5] in a study in athletes in the Swiss national ski teams. A knee injury rate of 35% was reported, with no differences between men and women; 71% were ACL injuries, of which 26% were isolated ACL injuries and 44% presented an associated injury of a collateral ligament and/or menisci. Their conclusion is that ACL is the most frequent knee injury in competitive alpine skiing. In their objective to describe risk factors for ACL injury, they report a higher risk in slalom runs (with more aggressive and technical turns but at lower speeds) and in athletes with better FIS score and rank, highlighting a higher prevalence of ACL ruptures in the top 30 World Cup skiers. Finally, body mass index, weight, and fitness status (assessed with a specific fitness test: Swiss Ski Power Test) did not correlate with ACL injury risk.

In two successive studies, Flørenes et al. [4] and Bere et al. [6] investigated the sex differences in risk injury in World Cup skiers, first for two seasons [4] and then for six seasons [6]. They report a mean absolute injury rate of 36.2 injuries/100 athletes/season with a higher relative injury rate in men (11.3 injuries/1000 runs)

than in women (7.1 injuries/1000 runs). Of this 82.3% were time-loss injuries, with 43% being reported as severe (absence from skiing >28 days) and 31% moderate (absence 8–28 days). 45.5% of the injuries took place during the World Cup races. Knee injuries represented the 38% and lower leg and Achilles tendon injuries the 9%. In ACL injuries, there were no sex differences (5.4 ACL injuries/100 athletes/ season in men vs. 5.5 in women).

When analyzing knee injuries, they reported that 83% were ligamentous injuries, of which 45% were ACL injuries (that makes the ACL the most common ligament injury), and only 4.4% were fractures. They report that 50% of knee injuries are classified as severe. The relative ACL injury rate was higher in downhill and supergiant races (high speed with softer turns) than in giant and slalom races; this result matches with Stenroos' study results [1].

In [7, 8], Jordan et al. made a review in which they report literature finding that only 55% of alpine skiing athletes are able to return to their preinjury level after an ACL rupture. They also support the result we have found that in this group of skiers there is no sex difference in ACL injury rates.

#### **4.2 Amateur skiers**

Referring to amateur skiers, Patrick et al. [2] made a study comparing injury epidemiology in skiers between the 1996 and 2013 seasons. In both years, the knee was the most commonly injured body part (28%). An interesting fact they report is that helmet use augmented from only 6 to 84%, which means that although there is an increasing effort to make skiing a safer sports this has had no impact on the amount of knee injuries. They also report and increase in injuries among people older than 45 years. This results match with the published by Stenroos et al. [1] when they report an injury risk of 1 injury/10,000 ski lifts or in their calculation 1.97 injuries/1000 skier days in amateur people. Knee lesions were the 28.5% of the total, almost half of them being suspected as moderate or severe injuries. A major limitation in this study, which is also present in similar ones, is the lack of precise diagnostics, as data is collected by rescuers and/or in small ski resort clinics.

Continuing with the epidemiology review, Girardi et al. [9] studied factors affecting injury severity using the Injury Severity Score (ISS). They found that being a man and being older than 60 years were risk factors for an increased ISS, while the ISS was lower in beginner skiers and during a snowfall. There is no information in this article about these risk factors relating to knee injury risk. In [10], Khalilifar et al. report a lower knee injury rate, of only 14%, but this rate being higher in women, a result also found in other studies [11–14].

In [15], Davidson and Laliotis, a 9-year survey (from 1983 to 1992) of injury patterns in alpine skiers, reported an increase in injury rate from 1.9 to 3 injuries/1000 skier days. Knee injuries were 35%, and what is more relevant is a 92% increase in the number of knee injuries during their study period.

A very similar study period is researched by Warme et al. in [16] reporting a stable injury rate of 3.7 injuries/1000 skier days and knee injuries being 34% of the total. The most relevant part is that they report an exact diagnostic information (30% of the total on injuries affected the knee ligaments): 18% the medial collateral ligament (MCL), 16.5% the ACL, and in 20% of knee sprains, both ligaments were affected. They report a significant increase in ACL injuries.

Coury et al. [17] compared the epidemiology of skiing injuries in a ski resort clinic between 1995 and 2000 and the 2009/2010 seasons. Their results show also the knee injury as the most frequent (43%). Knee ligament sprain or strain was diagnosed in 25% on injured people, 10% with torn cruciate ligament, and 6% with what they call "internal derangement of the knee" (probably, a torn meniscus was

**17**

*Ski Lesions Around the Knee: A Literature Review DOI: http://dx.doi.org/10.5772/intechopen.83646*

*4.2.1 Risk factors in amateur skiers*

to be diagnosed in this group of patients). Skiing injuries were more common in intermediate- or advanced-level skiers, but beginner skiers were the ones most at risk for knee injuries. They report only 3.2% on tibia and fibula fractures, and only 3.6% of ankle injuries in skiers, while snowboarders present up to 13% of ankle injuries. This difference may be explained by the use of hard-shell boots in ski. A recent interesting study [18] discusses about injuries from 2001 to 2006 in a level 1 trauma center, which probably means a loss of minor injuries but on the other hand can inform about the most severe ones. They report a 52.3% of lower extremity injuries, the majority classified as soft tissue knee injuries but with a 2% of knee dislocation, 26% of tibia fractures (ankle not included), and 15.7% of femur fractures. The mean hospitalization rate was of 3.36 days, and 13.9% of patients required a surgical intervention. In our opinion, the high rates of severe injuries, especially major bone fractures, are because of a selection bias due to the nature of the hospital where the study took place. Results published by Ekeland et al. [19] support our conclusion: injury rate of 1.27 injuries/1000 skier days with leg fractures being only 3.6% in adult population. In children these fractures made up to 12.6% of injuries. They conclude that while there was a huge reduction in leg fractures during the 1970s–1980s probably due to higher quality of boots, making them higher and hard-shelled, and bindings, this reduction was not observed in children to the same degree.

In the same direction point, the article by Castellani et al. [14] reported that fractures in skiers are more common in men and especially in younger patients (<15 years old). Knee injuries are the most common (28.3–31.3% of injuries), with knee fractures being between 2 and 5%. A result that is important to be highlighted is their finding of an increased risk in women for knee ligamentous injury: men presented 14–15% of ligamentous knee injuries and 36–41% in women. In their data, the hospitalization rate was of 26%, from which 62% underwent surgery; mean hospital stay was 10.5–12.8 days. Knee arthroscopy was realized in 1.9–6.3% of operations. These results can be biased by the fact that almost half of injured patients were referred to their home hospital for treatment of lesions; and as ligamentous injuries are not a surgical emergency, the probability of being referred to in the presence of such an injury grows when compared to a patient with a fracture.

Some studies did an effort to clarify which risk factors play a role in knee injuries in alpine skiers. As commented before this is a more heterogeneous group with big differences with respect to ski racers, so risk factors may be completely different. Sulheim et al. [20] reported that beginners (OR 2.7) and children younger than 13 years old (OR 1.32) were more at risk for injury. In their data, 27.3% of injuries affected the knee joint, and more than half of injuries required reference to a hospital as a potentially severe injury was suspected. When considering knee injuries alone, they also found that beginners (OR 3.13) were at increased risk, which matches results found by Coury et al. [17]. Alpine skiing was a risk factor for knee injury (OR 1.82)

Ruedl et al. [13] confirm that women are at higher risk for knee and ACL injuries presenting almost double prevalence for this kind of lesions in their data (30.1% in men and 57.4% in women). They report that 93% of knee injuries happened on slopes, and while off-piste skiing had a higher risk injury, it was not at an expense of knee ones. When analyzing by sex, no environmental risk factors for knee injury were found in men, while in women skiing during a snowfall doubled the prevalence on knee injuries compared with injuries of other body parts. Additionally, they found an increased risk when temperature was low (OR 1.6 when skiing at −10°C vs. +2.7°C). Finally, in this study more knee injuries were found in situations

when comparing with other snow sports like snowboarding and telemark.

#### *Ski Lesions Around the Knee: A Literature Review DOI: http://dx.doi.org/10.5772/intechopen.83646*

*Knee Surgery - Reconstruction and Replacement*

season in men vs. 5.5 in women).

**4.2 Amateur skiers**

this result matches with Stenroos' study results [1].

higher in women, a result also found in other studies [11–14].

the number of knee injuries during their study period.

affected. They report a significant increase in ACL injuries.

there is no sex difference in ACL injury rates.

than in women (7.1 injuries/1000 runs). Of this 82.3% were time-loss injuries, with 43% being reported as severe (absence from skiing >28 days) and 31% moderate (absence 8–28 days). 45.5% of the injuries took place during the World Cup races. Knee injuries represented the 38% and lower leg and Achilles tendon injuries the 9%. In ACL injuries, there were no sex differences (5.4 ACL injuries/100 athletes/

When analyzing knee injuries, they reported that 83% were ligamentous injuries, of which 45% were ACL injuries (that makes the ACL the most common ligament injury), and only 4.4% were fractures. They report that 50% of knee injuries are classified as severe. The relative ACL injury rate was higher in downhill and supergiant races (high speed with softer turns) than in giant and slalom races;

In [7, 8], Jordan et al. made a review in which they report literature finding that only 55% of alpine skiing athletes are able to return to their preinjury level after an ACL rupture. They also support the result we have found that in this group of skiers

Referring to amateur skiers, Patrick et al. [2] made a study comparing injury epidemiology in skiers between the 1996 and 2013 seasons. In both years, the knee was the most commonly injured body part (28%). An interesting fact they report is that helmet use augmented from only 6 to 84%, which means that although there is an increasing effort to make skiing a safer sports this has had no impact on the amount of knee injuries. They also report and increase in injuries among people older than 45 years. This results match with the published by Stenroos et al. [1] when they report an injury risk of 1 injury/10,000 ski lifts or in their calculation 1.97 injuries/1000 skier days in amateur people. Knee lesions were the 28.5% of the total, almost half of them being suspected as moderate or severe injuries. A major limitation in this study, which is also present in similar ones, is the lack of precise diagnostics, as data is collected by rescuers and/or in small ski resort clinics. Continuing with the epidemiology review, Girardi et al. [9] studied factors affecting injury severity using the Injury Severity Score (ISS). They found that being a man and being older than 60 years were risk factors for an increased ISS, while the ISS was lower in beginner skiers and during a snowfall. There is no information in this article about these risk factors relating to knee injury risk. In [10], Khalilifar et al. report a lower knee injury rate, of only 14%, but this rate being

In [15], Davidson and Laliotis, a 9-year survey (from 1983 to 1992) of injury patterns in alpine skiers, reported an increase in injury rate from 1.9 to 3 injuries/1000 skier days. Knee injuries were 35%, and what is more relevant is a 92% increase in

A very similar study period is researched by Warme et al. in [16] reporting a stable injury rate of 3.7 injuries/1000 skier days and knee injuries being 34% of the total. The most relevant part is that they report an exact diagnostic information (30% of the total on injuries affected the knee ligaments): 18% the medial collateral ligament (MCL), 16.5% the ACL, and in 20% of knee sprains, both ligaments were

Coury et al. [17] compared the epidemiology of skiing injuries in a ski resort clinic between 1995 and 2000 and the 2009/2010 seasons. Their results show also the knee injury as the most frequent (43%). Knee ligament sprain or strain was diagnosed in 25% on injured people, 10% with torn cruciate ligament, and 6% with what they call "internal derangement of the knee" (probably, a torn meniscus was

**16**

to be diagnosed in this group of patients). Skiing injuries were more common in intermediate- or advanced-level skiers, but beginner skiers were the ones most at risk for knee injuries. They report only 3.2% on tibia and fibula fractures, and only 3.6% of ankle injuries in skiers, while snowboarders present up to 13% of ankle injuries. This difference may be explained by the use of hard-shell boots in ski.

A recent interesting study [18] discusses about injuries from 2001 to 2006 in a level 1 trauma center, which probably means a loss of minor injuries but on the other hand can inform about the most severe ones. They report a 52.3% of lower extremity injuries, the majority classified as soft tissue knee injuries but with a 2% of knee dislocation, 26% of tibia fractures (ankle not included), and 15.7% of femur fractures. The mean hospitalization rate was of 3.36 days, and 13.9% of patients required a surgical intervention. In our opinion, the high rates of severe injuries, especially major bone fractures, are because of a selection bias due to the nature of the hospital where the study took place. Results published by Ekeland et al. [19] support our conclusion: injury rate of 1.27 injuries/1000 skier days with leg fractures being only 3.6% in adult population. In children these fractures made up to 12.6% of injuries. They conclude that while there was a huge reduction in leg fractures during the 1970s–1980s probably due to higher quality of boots, making them higher and hard-shelled, and bindings, this reduction was not observed in children to the same degree.

In the same direction point, the article by Castellani et al. [14] reported that fractures in skiers are more common in men and especially in younger patients (<15 years old). Knee injuries are the most common (28.3–31.3% of injuries), with knee fractures being between 2 and 5%. A result that is important to be highlighted is their finding of an increased risk in women for knee ligamentous injury: men presented 14–15% of ligamentous knee injuries and 36–41% in women. In their data, the hospitalization rate was of 26%, from which 62% underwent surgery; mean hospital stay was 10.5–12.8 days. Knee arthroscopy was realized in 1.9–6.3% of operations. These results can be biased by the fact that almost half of injured patients were referred to their home hospital for treatment of lesions; and as ligamentous injuries are not a surgical emergency, the probability of being referred to in the presence of such an injury grows when compared to a patient with a fracture.

#### *4.2.1 Risk factors in amateur skiers*

Some studies did an effort to clarify which risk factors play a role in knee injuries in alpine skiers. As commented before this is a more heterogeneous group with big differences with respect to ski racers, so risk factors may be completely different.

Sulheim et al. [20] reported that beginners (OR 2.7) and children younger than 13 years old (OR 1.32) were more at risk for injury. In their data, 27.3% of injuries affected the knee joint, and more than half of injuries required reference to a hospital as a potentially severe injury was suspected. When considering knee injuries alone, they also found that beginners (OR 3.13) were at increased risk, which matches results found by Coury et al. [17]. Alpine skiing was a risk factor for knee injury (OR 1.82) when comparing with other snow sports like snowboarding and telemark.

Ruedl et al. [13] confirm that women are at higher risk for knee and ACL injuries presenting almost double prevalence for this kind of lesions in their data (30.1% in men and 57.4% in women). They report that 93% of knee injuries happened on slopes, and while off-piste skiing had a higher risk injury, it was not at an expense of knee ones. When analyzing by sex, no environmental risk factors for knee injury were found in men, while in women skiing during a snowfall doubled the prevalence on knee injuries compared with injuries of other body parts. Additionally, they found an increased risk when temperature was low (OR 1.6 when skiing at −10°C vs. +2.7°C). Finally, in this study more knee injuries were found in situations

of grippy snow in which, as reported by them, this finding is contrary to other literature reporting a higher index on icy snow.

A very interesting study [11] researched the relationship between ACL injury and ski binding failure. In this study 77.9% of ACL-injured patients reported a failure of ski bindings to release. The percentage of failure to release bindings was even higher in female skiers, in skiers injured after a fall backward (vs. a forward fall), and in those who were skiing slow or very slow. There is always a significantly higher percentage of failure to release in patients diagnosed with a complete tear of the anterior cruciate ligament (vs. those with a partial tear), probably because when the ski is not released it acts as a lever at the knee joint for a longer time. Similar results are reported in [12]: bindings only released in 23.8% of knee-injured skiers, with an even worse percentage if only adults (>18 years old) are considered, and 19.3% of binding release among amateur skiers with a knee injury.

#### **5. Discussion**

In the elite alpine skiers, there is a high injury rate, especially in knee injuries and ACL. This high prevalence of knee ligament injuries can also be found in amateur skiers, but probably a more aggressive skiing and risk-taking behavior trying to achieve the best results is what explains the higher injury rate in this expert skiers' group. Comparing to studies done in general population, studies in ski racers present better data with more exact diagnostic information and prognosis. ACL and other knee structure injuries present the same incidence in both men and women; this was a surprising finding when taking into account what literature reports about amateur skiers and other high-risk sports for ACL injury: a higher incidence in women. Differences in skiing technique, fitness, behavior, and equipment between elite alpine skiers and amateurs may explain why ACL injury rate is equal in men and women, among ski racers. Whatever the reason is, in our opinion an effort should be made to minimize ACL injury risk in all athlete skiers, as it is a devastating injury that can be the end of the skier's professional career. We found no agreement in the literature about the most dangerous alpine ski discipline for the knee: slalom is characterized for aggressive technique with short turning-radius skis, which may be a risk factor of a knee ligament lesion with a rotational injury mechanism; on the other side, downhill and giant slalom are characterized for higher speeds, which means higher kinetic energy, plus the fact that a longer ski means a greater lever-arm rotational force being transmitted to the knee joint.

Even with the limitations present in studies involving amateur skiers due to their heterogeneity in methodology and limits on precise diagnostic, treatment, and follow-up, we found that the knee joint is the most frequently injured body part, and some studies show there is an increasing trend in ligamentous knee injuries among alpine skiers. Literature found reports that up to half of the injuries are moderate or severe, especially among older skiers, who present a higher injury risk and also a higher risk for serious injury. In our opinion this may be explained by the decrease in physical capabilities associated with aging. Another group at risk for knee injury is the beginner skiers; no explanations for this were found in the literature. In our opinion a poorer technique, bad decision taken related to poorer risk awareness, and probably less knowledge about the correct settings of equipment gear as ski bindings may explain it.

As also found in other sports studies, amateur women have a higher ACL injury risk when skiing. This was found to be supported widely in literature [10–14]. To explain this difference in incidence, we found literature suggesting on a combination of intrinsic factors: anthropometric differences, decreased notch width,

**19**

one of these groups.

knee injuries in skiers:

*Ski Lesions Around the Knee: A Literature Review DOI: http://dx.doi.org/10.5772/intechopen.83646*

efforts in the higher injury-risk groups.

**5.1 ACL biomechanics and injury mechanisms**

knee in extension, when the MCL has a decreasing role.

tion of the tibia with respect to the femur.

injury risk for knee structures.

in bad weather days.

augmented articular laxity and muscle (hamstring) flexibility, age, fitness status, and menstruation phases, plus the extrinsic ones such as the type of ski, ski binding setting, slope, and weather. We agree that most probably a combination of anatomic, functional, and extrinsic factors justifies this higher risk. The exact reasons have still to be discovered, but at least we should be able to focus the preventing

We found literature reporting that in 44% of lower extremity injuries (in 44% of MCL injuries and 43% of ACL injuries) skiers were going slow or were stationary, meaning that skiing slowly increments the risk for ACL injury and the risk of bindings fails to release. This last result probably explains the increased ACL injury risk in a fall when skiing slowly, as a lower kinetic energy, should mean a lower

Skiing in bad weather situations, lower temperature, and/or during a snowfall also were risk factors for knee injury, especially in women. The explanation for this last finding may be the increased risk of cooling which causes a decrease of muscle performance. In [13], there is reference to literature where a 10 times increase in ACL injury risk is reported in bad light conditions and also in case of strong snowfalls (double of risk) probably due to bad visibility plus lower temperatures. In our opinion bad visibility conditions like snowfalls are high-risk situations as it can make the skier to run into bumps able to turn the ski without being able to see and avoid it. This knowledge should be used to warn or even prevent people from skiing

As multiple articles in the literature report, the ACL is probably the most common injured ligament of the knee in alpine skiers. The second most common injured structure would be the MCL, although not all series agree on this order.

The anterior cruciate ligament is a primary stabilizer of the knee joint, being the main structure to resist tibia anterior translation with respect to the femur. It also restricts tibia internal rotation with knee between 0 and 30° of flexion, prevents hyperextension, and is a secondary stabilizer against the valgus, especially with the

The medial collateral ligament is the most important knee-stabilizing structure in the medial part of the joint; its main function is to resist the valgus forces and tibia internal rotation and has a secondary role in preventing the anterior transla-

As just seen both ligaments have similar or supplementary functions and are believed to act synergistically. This can explain the prevalence of combined total and partial injuries in skiing and other sports accidents. In other ACL injury highrisk sports, such as soccer, this lesion usually happens when with a foot planted on the ground the player does a sudden deceleration plus external rotation and/or valgus, presenting a twist at the level of the knee joint. Skiing mechanics involve a dual-surface movement [17], and skiers tend to sustain injuries when the ski catches

A consequence of special mechanics involved in skiing is that several injury mechanisms have been proposed. Shea et al. [12] affirm that injury mechanism in elite and amateur skiers might be different, a point partially supported by other literature when they report different percentages of each injury mechanism in each

In [12], and also in two interesting reviews [7, 21], proposed injury mechanisms are explained; a summary of this is of high interest for a better understanding of

an edge and there is a body torqueing with relation to the knee joint.

*Ski Lesions Around the Knee: A Literature Review DOI: http://dx.doi.org/10.5772/intechopen.83646*

*Knee Surgery - Reconstruction and Replacement*

**5. Discussion**

literature reporting a higher index on icy snow.

of grippy snow in which, as reported by them, this finding is contrary to other

19.3% of binding release among amateur skiers with a knee injury.

A very interesting study [11] researched the relationship between ACL injury and ski binding failure. In this study 77.9% of ACL-injured patients reported a failure of ski bindings to release. The percentage of failure to release bindings was even higher in female skiers, in skiers injured after a fall backward (vs. a forward fall), and in those who were skiing slow or very slow. There is always a significantly higher percentage of failure to release in patients diagnosed with a complete tear of the anterior cruciate ligament (vs. those with a partial tear), probably because when the ski is not released it acts as a lever at the knee joint for a longer time. Similar results are reported in [12]: bindings only released in 23.8% of knee-injured skiers, with an even worse percentage if only adults (>18 years old) are considered, and

In the elite alpine skiers, there is a high injury rate, especially in knee injuries and ACL. This high prevalence of knee ligament injuries can also be found in amateur skiers, but probably a more aggressive skiing and risk-taking behavior trying to achieve the best results is what explains the higher injury rate in this expert skiers' group. Comparing to studies done in general population, studies in ski racers present better data with more exact diagnostic information and prognosis. ACL and other knee structure injuries present the same incidence in both men and women; this was a surprising finding when taking into account what literature reports about amateur skiers and other high-risk sports for ACL injury: a higher incidence in women. Differences in skiing technique, fitness, behavior, and equipment between elite alpine skiers and amateurs may explain why ACL injury rate is equal in men and women, among ski racers. Whatever the reason is, in our opinion an effort should be made to minimize ACL injury risk in all athlete skiers, as it is a devastating injury that can be the end of the skier's professional career. We found no agreement in the literature about the most dangerous alpine ski discipline for the knee: slalom is characterized for aggressive technique with short turning-radius skis, which may be a risk factor of a knee ligament lesion with a rotational injury mechanism; on the other side, downhill and giant slalom are characterized for higher speeds, which means higher kinetic energy, plus the fact that a longer ski means a greater lever-arm rotational force being transmitted to the knee joint.

Even with the limitations present in studies involving amateur skiers due to their

As also found in other sports studies, amateur women have a higher ACL injury risk when skiing. This was found to be supported widely in literature [10–14]. To explain this difference in incidence, we found literature suggesting on a combination of intrinsic factors: anthropometric differences, decreased notch width,

heterogeneity in methodology and limits on precise diagnostic, treatment, and follow-up, we found that the knee joint is the most frequently injured body part, and some studies show there is an increasing trend in ligamentous knee injuries among alpine skiers. Literature found reports that up to half of the injuries are moderate or severe, especially among older skiers, who present a higher injury risk and also a higher risk for serious injury. In our opinion this may be explained by the decrease in physical capabilities associated with aging. Another group at risk for knee injury is the beginner skiers; no explanations for this were found in the literature. In our opinion a poorer technique, bad decision taken related to poorer risk awareness, and probably less knowledge about the correct settings of equip-

**18**

ment gear as ski bindings may explain it.

augmented articular laxity and muscle (hamstring) flexibility, age, fitness status, and menstruation phases, plus the extrinsic ones such as the type of ski, ski binding setting, slope, and weather. We agree that most probably a combination of anatomic, functional, and extrinsic factors justifies this higher risk. The exact reasons have still to be discovered, but at least we should be able to focus the preventing efforts in the higher injury-risk groups.

We found literature reporting that in 44% of lower extremity injuries (in 44% of MCL injuries and 43% of ACL injuries) skiers were going slow or were stationary, meaning that skiing slowly increments the risk for ACL injury and the risk of bindings fails to release. This last result probably explains the increased ACL injury risk in a fall when skiing slowly, as a lower kinetic energy, should mean a lower injury risk for knee structures.

Skiing in bad weather situations, lower temperature, and/or during a snowfall also were risk factors for knee injury, especially in women. The explanation for this last finding may be the increased risk of cooling which causes a decrease of muscle performance. In [13], there is reference to literature where a 10 times increase in ACL injury risk is reported in bad light conditions and also in case of strong snowfalls (double of risk) probably due to bad visibility plus lower temperatures. In our opinion bad visibility conditions like snowfalls are high-risk situations as it can make the skier to run into bumps able to turn the ski without being able to see and avoid it. This knowledge should be used to warn or even prevent people from skiing in bad weather days.

#### **5.1 ACL biomechanics and injury mechanisms**

As multiple articles in the literature report, the ACL is probably the most common injured ligament of the knee in alpine skiers. The second most common injured structure would be the MCL, although not all series agree on this order.

The anterior cruciate ligament is a primary stabilizer of the knee joint, being the main structure to resist tibia anterior translation with respect to the femur. It also restricts tibia internal rotation with knee between 0 and 30° of flexion, prevents hyperextension, and is a secondary stabilizer against the valgus, especially with the knee in extension, when the MCL has a decreasing role.

The medial collateral ligament is the most important knee-stabilizing structure in the medial part of the joint; its main function is to resist the valgus forces and tibia internal rotation and has a secondary role in preventing the anterior translation of the tibia with respect to the femur.

As just seen both ligaments have similar or supplementary functions and are believed to act synergistically. This can explain the prevalence of combined total and partial injuries in skiing and other sports accidents. In other ACL injury highrisk sports, such as soccer, this lesion usually happens when with a foot planted on the ground the player does a sudden deceleration plus external rotation and/or valgus, presenting a twist at the level of the knee joint. Skiing mechanics involve a dual-surface movement [17], and skiers tend to sustain injuries when the ski catches an edge and there is a body torqueing with relation to the knee joint.

A consequence of special mechanics involved in skiing is that several injury mechanisms have been proposed. Shea et al. [12] affirm that injury mechanism in elite and amateur skiers might be different, a point partially supported by other literature when they report different percentages of each injury mechanism in each one of these groups.

In [12], and also in two interesting reviews [7, 21], proposed injury mechanisms are explained; a summary of this is of high interest for a better understanding of knee injuries in skiers:


In elite skiers another two mechanisms have been described:

• Dynamic snowplow: with the weight backward and skis in split position, the unweighted ski forces the knee in valgus and internal rotation. It is believed to be the cause of 15% of ACL injury. It has big similarities with the hyperextension mechanism. The ACL, and also the MCL, limits knee valgus and internal

**21**

*Ski Lesions Around the Knee: A Literature Review DOI: http://dx.doi.org/10.5772/intechopen.83646*

after the injury took place [7].

although this last point is controversial [12].

injuries or even moderate to severe knee sprains.

80% decrease in tibia fractures since the 1970s.

to injury.

**5.2 Associated injuries**

rotation, so in this mechanism both structures are under strain and vulnerable

• Slip and catch: it is very similar to the previous one but is considered more frequent. This happens during a turn, after losing contact with the snow by the outer ski; when it recovers the ski catches the edge causing rapid flexion, internal rotation, and valgus. A very important reported fact is that in 100% of slip-catch ACL injuries in athletes ski bindings do not release or are release

These two mechanisms are believed to be related with the use of more aggressive and smaller turn radius skis like the ones used in slalom races; even some authors suggest that carving skies (shorter, wider in tip and tail, easier to turn) may augment the injury risk as their design may increase kinetic energy in slopes [7],

When an ACL injury occurs, other knee joint structures may be at risk, as up to 68% of skiers with an ACL injury present a lesion of another knee joint structure. If, as seen before, a valgus force is present in the injury mechanism, the medial collateral ligament will probably suffer a tear; the rate of associated ACL + MCL injury has been reported between 16 and 57% [21]. The isolated MCL injury is caused by a direct valgus load of the knee. A problem exist in preventing these injuries, as ski bindings are designed to release when falling forward or when rotating force is applied, so no releasing mechanism exists in cases of isolated valgus torque. In alpine skiing, the most commonly affected menisci is the lateral. This is reported to be found in 23–55% of ACL-injured knees. Some authors [2, 21] tried to explain the lower incidence of menisci lesions in ACL-injured knees when comparing to other ACL injury high-risk sports. The fact that some injury mechanisms are caused by forces that do not contain rotation or valgus may explain that. Another point is that, contrary to soccer or basketball, at the moment of injury in skiing there can be a distraction of the knee joint and by that not loading the meniscus and saving it from tears and less secondary trauma to the joint. Independent of the cause of a lower incidence of menisci, cartilage, and other joint structure injuries, this is a positive point, as all these lesions can be responsible for the onset of early osteoarthritis in young and active patients. In two literature reviews, we found contradictory affirmations about the trends in tibia plateau fractures, associated or not with ACL injury. In [3], authors report the finding of a rise in tibia plateau fractures, almost in all cases affecting the anterior part of the lateral plateau (Schatzker I, II, and III fractures) caused by valgus axial forces. In an opposite direction point, the results found in [21] report a 92% decrease in tibia plateau fractures from 1970 to 2003. In our literature review, reports about fractures affecting the knee joint are very scarce, and even some articles are done in ski resort clinics without RX; others are done in hospitals with all diagnostic methods available. In our opinion, it is very improbable that a tibia plateau fracture can go undiagnosed as the injured skier would not be able to go to his home hospital, a situation much more probable to happen in cases of minor

A conclusion present in the vast majority of literature reviewed is the low prevalence in ankle and lower leg injuries in adult skiers, either amateur or elite athletes. Ankle and tibia diaphysis fractures were once the most feared and frequent injuries; but there are [3] reports of a 92% decrease in ankle fractures and sprains and up to

*Knee Surgery - Reconstruction and Replacement*

nism in 19% of injured skiers.

• Valgus external rotation: after losing balance and shifting the center of gravity forward, the inside edge of the ski touches the ground producing abduction and external rotation of the tibia, while the skier's body advances respect to the knee, creating a valgus force. This mechanism is thought to damage the MCL and the ACL due to the valgus plus the rotation force applied to the knee. The presence of a valgus deformity may also cause a lateral meniscus traumatic tear. This was found to be the most common mechanism of injury in recreational skiers (up to 32.9% of cases) since the generalized use of carving skies [11, 12], and in one publication [12], it was related to high-level amateur skiers. This injury mechanism

was found to be related with the failure of ski bindings to release [11].

• Hyperextension internal rotation: occurring in heavy snow, it happens when the ski is slowed while the body keeps advancing forward. Usually, it associates a crossing of ski tips, producing internal rotation and varus force. The forced internal rotation in a probably extended knee is responsible for the ACL injury; as in an extended position, the ACL is the main knee joint restrictor against the internal rotation. This forced movement can also damage lateral structures like the lateral collateral ligament by distraction or the lateral meniscus if it is trapped under the femoral condyle when turning. This is the reported mecha-

• Boot-induced anterior drawer: when the skier lands from a jump, the ski tail is the first part to contact the snow causing the body weight to go backward while the leg is driven forward by the boot attached to the ski, applying an anterior force on the tibia. This effect can be increased by a strong quadriceps contraction to avoid a fall. With this mechanism the ACL is putted under great tension to avoid the anterior translation of the tibia with respect to the femur causing the injury. As the ACL is isolated and there is no rotation or varus-valgus deforming forces, the MCL and other knee structures remain unharmed. This mechanism was reported as the one responsible for only 7.8% of ACL injuries in amateur skiers [12], but it seems to be the most frequent mechanism in elite skiers [4]. Ski bindings are not designed to release when a backward-directed force is applied in the absence of rotational forces, so in this mechanism bindings will not release.

• Phantom foot: it happens when the skier losses balance and falls backward on the rear part of skis, placing the hips below the knees with all body weight on the downhill ski, which internally rotates the knee in hyperflexion. Knee hyperflexion puts the ACL under strain, which facilitates its injury due to the forced rotation. The MCL is also injured, as it is the main restrictor structure against internal rotation in the flexed knee. The fact that all body weight is on this ski makes the lateral meniscus vulnerable to injury as it can get trapped under the turning femoral condyle with axial load. This was reported as the most frequent mechanism before the introduction of carving skis [11], and a recent study reports a 22.5% of cases caused by this mechanism, being the second most frequent in skiers between 30 and 40 years old [12]. There is no agreement in literature about the influence of ski binding's failure to release in these cases.

• Dynamic snowplow: with the weight backward and skis in split position, the unweighted ski forces the knee in valgus and internal rotation. It is believed to be the cause of 15% of ACL injury. It has big similarities with the hyperextension mechanism. The ACL, and also the MCL, limits knee valgus and internal

In elite skiers another two mechanisms have been described:

**20**

rotation, so in this mechanism both structures are under strain and vulnerable to injury.

• Slip and catch: it is very similar to the previous one but is considered more frequent. This happens during a turn, after losing contact with the snow by the outer ski; when it recovers the ski catches the edge causing rapid flexion, internal rotation, and valgus. A very important reported fact is that in 100% of slip-catch ACL injuries in athletes ski bindings do not release or are release after the injury took place [7].

These two mechanisms are believed to be related with the use of more aggressive and smaller turn radius skis like the ones used in slalom races; even some authors suggest that carving skies (shorter, wider in tip and tail, easier to turn) may augment the injury risk as their design may increase kinetic energy in slopes [7], although this last point is controversial [12].

#### **5.2 Associated injuries**

When an ACL injury occurs, other knee joint structures may be at risk, as up to 68% of skiers with an ACL injury present a lesion of another knee joint structure.

If, as seen before, a valgus force is present in the injury mechanism, the medial collateral ligament will probably suffer a tear; the rate of associated ACL + MCL injury has been reported between 16 and 57% [21]. The isolated MCL injury is caused by a direct valgus load of the knee. A problem exist in preventing these injuries, as ski bindings are designed to release when falling forward or when rotating force is applied, so no releasing mechanism exists in cases of isolated valgus torque.

In alpine skiing, the most commonly affected menisci is the lateral. This is reported to be found in 23–55% of ACL-injured knees. Some authors [2, 21] tried to explain the lower incidence of menisci lesions in ACL-injured knees when comparing to other ACL injury high-risk sports. The fact that some injury mechanisms are caused by forces that do not contain rotation or valgus may explain that. Another point is that, contrary to soccer or basketball, at the moment of injury in skiing there can be a distraction of the knee joint and by that not loading the meniscus and saving it from tears and less secondary trauma to the joint. Independent of the cause of a lower incidence of menisci, cartilage, and other joint structure injuries, this is a positive point, as all these lesions can be responsible for the onset of early osteoarthritis in young and active patients.

In two literature reviews, we found contradictory affirmations about the trends in tibia plateau fractures, associated or not with ACL injury. In [3], authors report the finding of a rise in tibia plateau fractures, almost in all cases affecting the anterior part of the lateral plateau (Schatzker I, II, and III fractures) caused by valgus axial forces. In an opposite direction point, the results found in [21] report a 92% decrease in tibia plateau fractures from 1970 to 2003. In our literature review, reports about fractures affecting the knee joint are very scarce, and even some articles are done in ski resort clinics without RX; others are done in hospitals with all diagnostic methods available. In our opinion, it is very improbable that a tibia plateau fracture can go undiagnosed as the injured skier would not be able to go to his home hospital, a situation much more probable to happen in cases of minor injuries or even moderate to severe knee sprains.

A conclusion present in the vast majority of literature reviewed is the low prevalence in ankle and lower leg injuries in adult skiers, either amateur or elite athletes. Ankle and tibia diaphysis fractures were once the most feared and frequent injuries; but there are [3] reports of a 92% decrease in ankle fractures and sprains and up to 80% decrease in tibia fractures since the 1970s.

A general agreement is found in the literature and is also of our opinion that the reason for such a decrease in lower leg injuries while knee injury rates have grown or at least maintained is the change in the skier's equipment. Back in the 1960–1970s, ski boots were made of leather, shorter, and soft-shelled. It is evident that a major change has occurred; nowadays, boots are made of plastic, hard-shelled, and much higher than before. Ski is still a high-risk sports, with falls with or without collision being very frequent; and the kinetic energy of the fall is the same than it was 30–40 years ago. With actual equipment these forces bypass the ankle joint and the leg with all the energy absorbed and dissipated at the knee joint's level. In the authors' opinion, the sole fact of the existence of an injury mechanism called "boot-induced anterior drawer" should be enough to prove this point.

Another gear part that has had major improvements in quality is ski bindings. It is very probable that these changes also played a role in the decrease of lower leg fractures and are considered as key safety equipment. Ski bindings are designed to release when there is a fall forward with or without body rotation (reproducing the most frequent injury mechanisms) but are not done to free the skier's foot in case of a backward fall. In our opinion this is a big design deficiency that has to be fixed soon if there is a will to make skiing a safer sports. The problem now is that, as explained previously, several articles report high percentages of ski binding failure to release, especially linked to some injury mechanisms. In our opinion these equipment failures' high rates are to be considered unacceptable, and efforts have to be made to keep improving with the goal of reducing skiing injuries, particularly those affecting the knee joint.

#### **5.3 Treatment**

When considering the management and treatment of knee skiing injuries, the first thing that surprised us is that the majority of authors made no reference to it. Publications using small ski resort clinics, some of them without physician and/ or diagnostic tools, admit its limitations and explain their procedure for referring patients with a suspected severe injury to hospitals. In other cases, with data obtained from these near hospitals, great treatment and follow-up evolution are lost when referring the patient for definitive treatment to his/her home hospital [14]. A limitation present in both study types is that of skiers with minor or moderate injuries that do not seek medical attention or that do it later in their home hospital.

Only in [1] et al. report the time loss after an ACL injury in elite skiers, but many times this is a population group with big differences in treatment strategies and goals.

Nowadays, the gold standard treatment for an ACL complete tear in a relatively young and active patient is its reconstruction. Debate about the better technique (mono- vs. bifascicular reconstruction, type of graft, graft fixation, etc.) is a topic outside this review's objectives.

It is also generally accepted that the treatment for an isolated MCL injury is a conservative treatment, which is thought to heal without sequels. There is less evidence about the best treatment of ACL and MCL combined injury.

Some surgeons affirm that the best method is to treat each injury in its gold standard way: surgical reconstruction of the ACL and conservative treatment for the MCL. Others argue that in a combined injury an anterior and valgus instability is present and that for this reason the MCL will not heal properly in the presence of an injured ACL. To solve this problem, there are two options, an operative reconstruction of all injured structures and an early surgery for ACL treatment, which would allow for a successful MCL non-operative treatment.

In our opinion, the majority of combined injuries should be treated with surgery but only for ACL reconstruction. We do not agree with the idea that an early ACL

**23**

provided the original work is properly cited.

*Ski Lesions Around the Knee: A Literature Review DOI: http://dx.doi.org/10.5772/intechopen.83646*

**6. Conclusion**

**Conflict of interest**

**Author details**

Andrea Sallent6

Guillem Navarro Escarp1

Authors declare no conflict of interest.

1 Hospital Clínic de Barcelona, Barcelona, Spain

2 Centro Médico Teknon, Barcelona, Spain

3 Universitat de Barcelona, Barcelona, Spain

6 Hospital Vall d'hebron, Barcelona, Spain

4 Hospital Quiron Barcelona, Barcelona, Spain

5 Universitat Internacional de Catalunya, Barcelona, Spain

\*Address all correspondence to: arestraumatologia@gmail.com

reconstruction surgery is needed; in fact, for us a delayed ACL surgery is a better option, waiting until medial stability is recovered. Only in cases with a grade III MCL tear with great knee instability after at least 2 months of MCL tear conservative treatment, we recommend its surgical treatment, with plasty reconstruction of both structures.

Alpine skiing is a high-risk sports with an elevated number of people injured every year. Ligamentous knee injuries are among the most common, and it does not seems to be any tendency to decrease its high rate despite changes in attitudes and equipment that have lowered the number of other serious injuries. As seen, the percentage of knee injuries that can be considered severe is high, with ACL tears as the most common knee injury. Having such high rates of serious injuries in alpine skier's knee implies big challenges in prevention, to identify skiers at risk and to improve equipment parts that are proven to be failing. More research needs to be done to define all risk factors so that prevention efforts can be well directed. Also, more research is needed to identify the best treatment option for ACL and other knee ligamentous injuries, and consensus in treatment and rehabilitation protocols

are needed for both elite athletes and amateur-injured alpine skiers.

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

, Oscar Ares Rodriguez1,2,3\*, Ignacio Moya Molinas1

Pilar Camacho Carrasco1,3, Alonso Zumbado Dijeres1,3, Roberto Seijas Vazquez4,5,

, Manuel Llusa Pérez1,3 and Andreu Combalia Aleu1,3

,

reconstruction surgery is needed; in fact, for us a delayed ACL surgery is a better option, waiting until medial stability is recovered. Only in cases with a grade III MCL tear with great knee instability after at least 2 months of MCL tear conservative treatment, we recommend its surgical treatment, with plasty reconstruction of both structures.

### **6. Conclusion**

*Knee Surgery - Reconstruction and Replacement*

anterior drawer" should be enough to prove this point.

of reducing skiing injuries, particularly those affecting the knee joint.

A general agreement is found in the literature and is also of our opinion that the reason for such a decrease in lower leg injuries while knee injury rates have grown or at least maintained is the change in the skier's equipment. Back in the 1960–1970s, ski boots were made of leather, shorter, and soft-shelled. It is evident that a major change has occurred; nowadays, boots are made of plastic, hard-shelled, and much higher than before. Ski is still a high-risk sports, with falls with or without collision being very frequent; and the kinetic energy of the fall is the same than it was 30–40 years ago. With actual equipment these forces bypass the ankle joint and the leg with all the energy absorbed and dissipated at the knee joint's level. In the authors' opinion, the sole fact of the existence of an injury mechanism called "boot-induced

Another gear part that has had major improvements in quality is ski bindings. It is very probable that these changes also played a role in the decrease of lower leg fractures and are considered as key safety equipment. Ski bindings are designed to release when there is a fall forward with or without body rotation (reproducing the most frequent injury mechanisms) but are not done to free the skier's foot in case of a backward fall. In our opinion this is a big design deficiency that has to be fixed soon if there is a will to make skiing a safer sports. The problem now is that, as explained previously, several articles report high percentages of ski binding failure to release, especially linked to some injury mechanisms. In our opinion these equipment failures' high rates are to be considered unacceptable, and efforts have to be made to keep improving with the goal

When considering the management and treatment of knee skiing injuries, the first thing that surprised us is that the majority of authors made no reference to it. Publications using small ski resort clinics, some of them without physician and/ or diagnostic tools, admit its limitations and explain their procedure for referring patients with a suspected severe injury to hospitals. In other cases, with data obtained from these near hospitals, great treatment and follow-up evolution are lost when referring the patient for definitive treatment to his/her home hospital [14]. A limitation present in both study types is that of skiers with minor or moderate injuries that do not seek medical attention or that do it later in their home hospital. Only in [1] et al. report the time loss after an ACL injury in elite skiers, but many

times this is a population group with big differences in treatment strategies and

Nowadays, the gold standard treatment for an ACL complete tear in a relatively young and active patient is its reconstruction. Debate about the better technique (mono- vs. bifascicular reconstruction, type of graft, graft fixation, etc.) is a topic

It is also generally accepted that the treatment for an isolated MCL injury is a conservative treatment, which is thought to heal without sequels. There is less

Some surgeons affirm that the best method is to treat each injury in its gold standard way: surgical reconstruction of the ACL and conservative treatment for the MCL. Others argue that in a combined injury an anterior and valgus instability is present and that for this reason the MCL will not heal properly in the presence of an injured ACL. To solve this problem, there are two options, an operative reconstruction of all injured structures and an early surgery for ACL treatment, which

In our opinion, the majority of combined injuries should be treated with surgery but only for ACL reconstruction. We do not agree with the idea that an early ACL

evidence about the best treatment of ACL and MCL combined injury.

would allow for a successful MCL non-operative treatment.

**22**

**5.3 Treatment**

goals.

outside this review's objectives.

Alpine skiing is a high-risk sports with an elevated number of people injured every year. Ligamentous knee injuries are among the most common, and it does not seems to be any tendency to decrease its high rate despite changes in attitudes and equipment that have lowered the number of other serious injuries. As seen, the percentage of knee injuries that can be considered severe is high, with ACL tears as the most common knee injury. Having such high rates of serious injuries in alpine skier's knee implies big challenges in prevention, to identify skiers at risk and to improve equipment parts that are proven to be failing. More research needs to be done to define all risk factors so that prevention efforts can be well directed. Also, more research is needed to identify the best treatment option for ACL and other knee ligamentous injuries, and consensus in treatment and rehabilitation protocols are needed for both elite athletes and amateur-injured alpine skiers.

### **Conflict of interest**

Authors declare no conflict of interest.

### **Author details**

Guillem Navarro Escarp1 , Oscar Ares Rodriguez1,2,3\*, Ignacio Moya Molinas1 , Pilar Camacho Carrasco1,3, Alonso Zumbado Dijeres1,3, Roberto Seijas Vazquez4,5, Andrea Sallent6 , Manuel Llusa Pérez1,3 and Andreu Combalia Aleu1,3


\*Address all correspondence to: arestraumatologia@gmail.com

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

### **References**

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[6] Bere T, Flørenes TW, Nordsletten L, Bahr R. Sex differences in the risk of injury in world cup alpine skiers: A 6-year cohort study. British Journal of Sports Medicine. 2014;**48**(1):36-40

[7] Jordan M, Aagaard P, Herzog W. Anterior cruciate ligament injury/ reinjury in alpine ski racing: A narrative review. Open Access Journal of Sports Medicine. 2017;**8**:71-83

[8] Ruedl G, Philippe M, Sommersacher R, Duennwald T, Kopp M, Burtscher M. Current incidence of accidents on Austrian Ski slopes. Sportverletzung-Sportschaden. 2014;**28**(4):183-187

[9] Girardi P, Braggion M, Sacco G, de Giorgi F, Corra S. Factors affecting injury severity among recreational skiers and snowboarders: An epidemiology study. Knee Surgery, Sport Traumatol Arthrosc. 2010;**18**(12):1804-1809

[10] Khalilifar AH, Kazemi MH, Hamedanchi A, Hosseini MJ. Skiing injuries at the Dizin ski resort. Trauma Monthly. 2012;**17**(1):259-261

[11] Ruedl G, Helle K, Tecklenburg K, Schranz A, Fink C, Burtscher M. Factors associated with self-reported failure of binding release among ACL injured male and female recreational skiers: A catalyst to change ISO binding standards? British Journal of Sports Medicine. 2016;**50**(1):37-40

[12] Shea KG, Archibald-Seiffer N, Murdock E, Grimm NL, Jacobs JC, Willick S, et al. Knee injuries in downhill skiers: A 6-year survey study. Orthopaedic Journal of Sports Medicine. 2014;**2**(1):1-6

[13] Ruedl G, Fink C, Schranz A, Sommersacher R, Nachbauer W, Burtscher M. Impact of environmental factors on knee injuries in male and female recreational skiers. Scandinavian Journal of Medicine & Science in Sports. 2012;**22**(2):185-189

[14] Castellani C, Singer G, Kaiser M, Petnehazy T, et al. An epidemiologic analysis of winter sport accidents on ski slopes comparing two seasons. The Journal of Sports Medicine and Physical Fitness. 2018

[15] Davidson TM, Laliotis AT. Alpine skiing injuries. A nine-year study. The Western Journal of Medicine. 1996;**164**(4):310-314

[16] Warme WJ, John A, King P, Lambert KL, Cunningham RR, Hole J. Injury statistics, 1982-1993 Jackson Hole Ski

**25**

*Ski Lesions Around the Knee: A Literature Review DOI: http://dx.doi.org/10.5772/intechopen.83646*

Resort. American Journal of Sports Medicine. 1993;**23**(5):597-600

[17] Coury T, Napoli AM, Wilson M, Daniels J, Murray T, Milzman D. Injury patterns in recreational alpine skiing and snowboarding at a mountainside clinic. Wilderness & Environmental Medicine. 2013;**24**(4):417-421

[18] Wasden CC, McIntosh SE, Keith DS, McCowan C. An analysis of skiing and snowboarding injuries on Utah slopes. Journal of Trauma, Injury, Infection, and Critical Care. 2009;**67**(5):1022-1026

[19] Ekeland A, Rødven A, Heir S. Injuries among children and adults in alpine skiing and snowboarding. Journal of Science and Medicine in Sport.

[20] Sulheim S, Holme I, Rødven A, Ekeland A, Bahr R. Risk factors for injuries in alpine skiing, telemark skiing and snowboarding—Case-control study. British Journal of Sports Medicine.

[21] Pressman A, Johnson DH. A review of ski injuries resulting in combined injury to the anterior cruciate ligament and medial collateral ligaments. Arthroscopy: The Journal of Arthroscopic & Related Surgery.

2011;**45**(16):1303-1309

2003;**19**(2):194-202

2018:11-14

*Ski Lesions Around the Knee: A Literature Review DOI: http://dx.doi.org/10.5772/intechopen.83646*

Resort. American Journal of Sports Medicine. 1993;**23**(5):597-600

[17] Coury T, Napoli AM, Wilson M, Daniels J, Murray T, Milzman D. Injury patterns in recreational alpine skiing and snowboarding at a mountainside clinic. Wilderness & Environmental Medicine. 2013;**24**(4):417-421

[18] Wasden CC, McIntosh SE, Keith DS, McCowan C. An analysis of skiing and snowboarding injuries on Utah slopes. Journal of Trauma, Injury, Infection, and Critical Care. 2009;**67**(5):1022-1026

[19] Ekeland A, Rødven A, Heir S. Injuries among children and adults in alpine skiing and snowboarding. Journal of Science and Medicine in Sport. 2018:11-14

[20] Sulheim S, Holme I, Rødven A, Ekeland A, Bahr R. Risk factors for injuries in alpine skiing, telemark skiing and snowboarding—Case-control study. British Journal of Sports Medicine. 2011;**45**(16):1303-1309

[21] Pressman A, Johnson DH. A review of ski injuries resulting in combined injury to the anterior cruciate ligament and medial collateral ligaments. Arthroscopy: The Journal of Arthroscopic & Related Surgery. 2003;**19**(2):194-202

**24**

*Knee Surgery - Reconstruction and Replacement*

[1] Stenroos AJ, Handolin LE. Alpine skiing injuries in Finland—A twoyear retrospective study based on a questionnaire among ski racers. BMC Sports Science, Medicine and Rehabilitation. 2014;**6**(1):2-6

[9] Girardi P, Braggion M, Sacco G, de Giorgi F, Corra S. Factors affecting injury severity among recreational skiers and snowboarders:

An epidemiology study. Knee Surgery, Sport Traumatol Arthrosc.

[10] Khalilifar AH, Kazemi MH, Hamedanchi A, Hosseini MJ. Skiing injuries at the Dizin ski resort. Trauma

[11] Ruedl G, Helle K, Tecklenburg K, Schranz A, Fink C, Burtscher M. Factors associated with self-reported failure of binding release among ACL injured male and female recreational skiers: A catalyst to change ISO binding standards? British Journal of Sports

Monthly. 2012;**17**(1):259-261

Medicine. 2016;**50**(1):37-40

[12] Shea KG, Archibald-Seiffer N,

of Sports Medicine. 2014;**2**(1):1-6

[13] Ruedl G, Fink C, Schranz A, Sommersacher R, Nachbauer W, Burtscher M. Impact of environmental factors on knee injuries in male and female recreational skiers. Scandinavian Journal of Medicine & Science in Sports.

[14] Castellani C, Singer G, Kaiser M, Petnehazy T, et al. An epidemiologic analysis of winter sport accidents on ski slopes comparing two seasons. The Journal of Sports Medicine and Physical

[15] Davidson TM, Laliotis AT. Alpine skiing injuries. A nine-year study. The Western Journal of Medicine.

[16] Warme WJ, John A, King P, Lambert KL, Cunningham RR, Hole J. Injury statistics, 1982-1993 Jackson Hole Ski

2012;**22**(2):185-189

Fitness. 2018

1996;**164**(4):310-314

Murdock E, Grimm NL, Jacobs JC, Willick S, et al. Knee injuries in downhill skiers: A 6-year survey study. Orthopaedic Journal

2010;**18**(12):1804-1809

[2] Patrick E, Cooper JG, Daniels J. Changes in skiing and snowboarding injury epidemiology and attitudes to safety in big sky, Montana, USA: A comparison of 2 cross-sectional studies in 1996 and 2013. Orthopaedic Journal of Sports Medicine. 2015;**3**(6):1-6

[3] Hunter RE. Current concepts skiing injuries. Sports Medicine.

[4] Flørenes TW, Bere T, Nordsletten L, Heir S, Bahr R. Injuries among male and female world cup alpine skiers. British Journal of Sports Medicine.

[5] Schmitt K-U, Hörterer N, Vogt M, Frey WO, Lorenzetti S. Investigating physical fitness and race performance as determinants for the ACL injury risk in alpine ski racing. BMC Sports Science, Medicine and Rehabilitation.

[6] Bere T, Flørenes TW, Nordsletten L, Bahr R. Sex differences in the risk of injury in world cup alpine skiers: A 6-year cohort study. British Journal of Sports Medicine. 2014;**48**(1):36-40

[7] Jordan M, Aagaard P, Herzog W. Anterior cruciate ligament injury/ reinjury in alpine ski racing: A narrative review. Open Access Journal of Sports

Sommersacher R, Duennwald T, Kopp M, Burtscher M. Current incidence of accidents on Austrian Ski slopes. Sportverletzung-Sportschaden.

Medicine. 2017;**8**:71-83

2014;**28**(4):183-187

[8] Ruedl G, Philippe M,

2000;**27**(3):381-389

2009;**43**(13):973-978

2016;**8**(1):23

**References**

**27**

**1. Introduction**

**Chapter 3**

**Abstract**

Techniques

*Tahsin Gurpinar*

Decision-Making for ALL

Reconstruction and Surgical

The anterolateral ligament (ALL), which was first described in 1879, was reintroduced in 2013 by Claes et al. It originates near the lateral epicondyle of the distal femur, runs along the lateral outer aspect of the knee, and inserts on the proximal tibia between Gerdy's tubercle and fibular head. The ALL tightens when the knee is internally rotated (twisted inwards), and in doing so, it is proposed to be a stabilizer to internal tibial rotation. Biomechanical studies showed that the ALL restrains internal rotation of the tibia and thus affects the pivot-shift phenomenon in the anterior cruciate ligament (ACL)-injured knee. Therefore, it is proposed that the deficient ALL can be a reason for persistent rotatory instability after ACL reconstruction. Furthermore, ALL reconstruction techniques have evolved and indications extended. Commonly accepted indications for concomitant ACL and ALL reconstruction are ACL revisions, high-grade pivot-shift test, chronic ACL rupture, and young patients and patients doing pivoting activities. Most surgeons perform an anatomic reconstruction technique with gracilis autograft. However, only few studies published reporting the outcomes of ALL reconstruction and more studies with longer follow-up times are, therefore, needed to provide the compelling

clinical evidence for the efficacy of concomitant ACL and ALL procedures.

indications for ALL reconstruction, anterior cruciate ligament, pivot shift

The anterolateral ligament (ALL) is a newly re-introduced ligament on the lateral aspect of the knee, which originates at the lateral epicondyle of the femur, and inserts at the anterolateral aspect of the proximal tibia. It was first described by Paul Segond as "a pearly, resistant, fibrous band" at the anterolateral aspect of the human knee; however, it was not given much importance until Claes et al. identified the ALL in an anatomic study as a distinct structure of the lateral compartment of the knee [1]. Subsequently, many studies have been published regarding the

The clinical relevance of ALL mostly comes from its high association with anterior cruciate ligament (ACL) injuries. Studies showed a high incidence of radiological ALL damage (78.7%) in ACL-injured knees [2]. Biomechanically, it is claimed to be a stabilizer in internal rotation of the tibia particularly at high knee flexion

**Keywords:** anterolateral ligament, ALL reconstruction,

anatomy, biomechanics, and radiology of ALL.

#### **Chapter 3**

## Decision-Making for ALL Reconstruction and Surgical Techniques

*Tahsin Gurpinar*

#### **Abstract**

The anterolateral ligament (ALL), which was first described in 1879, was reintroduced in 2013 by Claes et al. It originates near the lateral epicondyle of the distal femur, runs along the lateral outer aspect of the knee, and inserts on the proximal tibia between Gerdy's tubercle and fibular head. The ALL tightens when the knee is internally rotated (twisted inwards), and in doing so, it is proposed to be a stabilizer to internal tibial rotation. Biomechanical studies showed that the ALL restrains internal rotation of the tibia and thus affects the pivot-shift phenomenon in the anterior cruciate ligament (ACL)-injured knee. Therefore, it is proposed that the deficient ALL can be a reason for persistent rotatory instability after ACL reconstruction. Furthermore, ALL reconstruction techniques have evolved and indications extended. Commonly accepted indications for concomitant ACL and ALL reconstruction are ACL revisions, high-grade pivot-shift test, chronic ACL rupture, and young patients and patients doing pivoting activities. Most surgeons perform an anatomic reconstruction technique with gracilis autograft. However, only few studies published reporting the outcomes of ALL reconstruction and more studies with longer follow-up times are, therefore, needed to provide the compelling clinical evidence for the efficacy of concomitant ACL and ALL procedures.

**Keywords:** anterolateral ligament, ALL reconstruction, indications for ALL reconstruction, anterior cruciate ligament, pivot shift

#### **1. Introduction**

The anterolateral ligament (ALL) is a newly re-introduced ligament on the lateral aspect of the knee, which originates at the lateral epicondyle of the femur, and inserts at the anterolateral aspect of the proximal tibia. It was first described by Paul Segond as "a pearly, resistant, fibrous band" at the anterolateral aspect of the human knee; however, it was not given much importance until Claes et al. identified the ALL in an anatomic study as a distinct structure of the lateral compartment of the knee [1]. Subsequently, many studies have been published regarding the anatomy, biomechanics, and radiology of ALL.

The clinical relevance of ALL mostly comes from its high association with anterior cruciate ligament (ACL) injuries. Studies showed a high incidence of radiological ALL damage (78.7%) in ACL-injured knees [2]. Biomechanically, it is claimed to be a stabilizer in internal rotation of the tibia particularly at high knee flexion

angles; however, the biomechanical role of ALL is still the subject of debate [3, 4]. This chapter reviews the main features related to ALL and focuses on the current indications and techniques of ALL reconstruction.

#### **2. Anatomy**

The anatomy of the ALL has been investigated by several authors in order to accurately identify the features of the structure. There has been some debate regarding the exact attachments of the ligament; however, it is generally accepted that the ALL is a distinctive triangular, anterolateral structure under the iliotibial band (ITB). Investigations of the anatomy of the ALL in several cadavers have revealed variability of the structure particularly for the femoral attachment. The femoral origin is located at the lateral femoral epicondyle (LFE) at either the identical position of the origin of the fibular collateral ligament (FCL) or just posterior and proximal to it with the average width at this point 11.85 mm [5]. The ALL then runs distally by overlapping the proximal portion of the lateral collateral ligament, and some fibers of the ALL are attached to the lateral meniscus and the anterolateral capsule at the level of knee joint. The majority of the fibers continue to run distally and attach midway between the tip of the fibular head and GT (**Figure 1**). The tibial attachment is 12.2 ± 3.0 mm width and is centered 21.6 mm posterior to Gerdy's tubercle, and 4–10 mm far from the joint line [1, 6–8]. The mean length of the structure has been measured between 34 and 59 mm from its femoral origin to tibial attachment [7, 8]. The thickness of ALL also varies and has been measured as 2.09 mm in males and 1.09 mm in females [9].

#### **Figure 1.**

*Anterolateral ligament anatomy (ITB: iliotibial band, ALL: anterolateral ligament, FH: fibular head, GT: Gerdy's tubercle, and LCL: lateral collateral ligament).*

#### **3. Biomechanics**

Zens et al. [10] found that the isolated ALL had an ultimate tensile strength of 50 ± 15 N, at a strain of 36 ± 4%. With a mean cross-sectional area of only 1.54 mm2 , the ultimate tensile stress was 33 ± 4 MPa and the overall stiffness was 4.2 N/ mm extension. However, Kennedy et al. [11] reported that the ALL had a tensile

**29**

*Decision-Making for ALL Reconstruction and Surgical Techniques*

strength of 175 N (139–211 N 95% CI) and stiffness 20 N/mm [12–21] with a more substantial structure than that shown by Zens et al. [10]. The mean ultimate load to failure and the mean stiffness of ALL have been measured between 50 and 205 N

In most of the studies, the ALL is described as a secondary stabilizer to internal rotation and to some extent anterior translation [3, 24, 25]. The biomechanical studies demonstrated that in the presence of ACL deficiency, sectioning the ALL in cadaveric specimens significantly effects the anteroposterior (AP) stability as well as results in a significant increase in internal rotation [12, 24]. The contribution of the ALL during internal rotation increases significantly with increasing flexion, whereas that of the ACL decreased significantly. Therefore, it is speculated that the ALL deficiency can be a reason for persistent rotational instability after ACL

The isometry of the ALL was measured by Dodds et al. [7], by threading a suture along the ligament fibers, attaching it to the moving tibia and then measuring the changes of the separation distance between the attachments using a transducer. It was shown that the ALL was not isometric, but was close to being isometric from 0 to 60° knee flexion. Internal tibial rotation increased the length between the attachments, and external rotation reduced it. When the knee was in extension, tibial rotations in response to 5 Nm torque were not large enough to cause significant change in the length of the ALL. However, internal tibial rotation increased the mean length between the ALL attachments from 3.6 mm (SD 0.7; 1.5–5.7) at 30° (p = 0.003) to 9.9 mm (SD 1.4; 5.7–14.2) at 90° of flexion of the knee. Imbert et al. [14] investigated isometric characteristics of the ALL in a cadaveric navigation study and found that ALL is not isometric at any of the femoral insertion locations but had different length change patterns during knee flexion and internal tibial rotation at 90°. However, they found that the proximal and posterior to epicondyle

Injury to the ALL is most commonly associated with a concomitant tear of the ACL. In a retrospective MRI study, Claes et al. [2] analyzed 206 ACL injured knees and found 78.8% radiological ALL abnormalities. Most of the ALL abnormalities were found to be situated in the distal part of the ligament (77.8%), whereas 20.4% of the injuries were proximal and only 1.8% knees were diagnosed with a bony ALL avulsion. Ferretti et al. [15] exposed the lateral knee compartments of 60 patients undergoing ACLR and found several lesion types of the ALL injuries including macroscopic hemorrhage extending to the anterolateral capsule (32%) or to the posterolateral capsule (27%), complete transverse tear of the ALL near its tibial insertion (22%), and a bony tibial avulsion (Segond fracture) (10%). In a retrospective MRI study, Gurpinar et al. found 65.2% ALL injury in patients underwent ACL surgery who were diagnosed with isolated ACL injury previously [13]. In a similar study, van Dyck et al. [16] found ALL abnormalities in 46% of 90 knee MRIs of patients with an acute ACL rupture. Furthermore, they found that these patients were more likely to have a lateral meniscal tear, collateral ligament injury, or osseous injury

After re-discovery of ALL, Segond fractures, which were previously considered as a diagnostic clue for ACL injury, are classified as ALL equivalent injuries [17]. Porrino et al. [18] evaluated 20 knee MRIs with a Segond fracture and found that the ALL was attached to the fracture fragment in all but one case limited by anatomic distortion. Claes et al. [17] also suggested that the Segond fracture is actually

and between 20 and 42 N/mm, respectively, in different studies [11, 22, 23].

*DOI: http://dx.doi.org/10.5772/intechopen.86398*

femoral position is favorable to being isometry.

compared with patients with an intact ALL.

reconstruction [13].

**4. Injury**

#### *Decision-Making for ALL Reconstruction and Surgical Techniques DOI: http://dx.doi.org/10.5772/intechopen.86398*

strength of 175 N (139–211 N 95% CI) and stiffness 20 N/mm [12–21] with a more substantial structure than that shown by Zens et al. [10]. The mean ultimate load to failure and the mean stiffness of ALL have been measured between 50 and 205 N and between 20 and 42 N/mm, respectively, in different studies [11, 22, 23].

In most of the studies, the ALL is described as a secondary stabilizer to internal rotation and to some extent anterior translation [3, 24, 25]. The biomechanical studies demonstrated that in the presence of ACL deficiency, sectioning the ALL in cadaveric specimens significantly effects the anteroposterior (AP) stability as well as results in a significant increase in internal rotation [12, 24]. The contribution of the ALL during internal rotation increases significantly with increasing flexion, whereas that of the ACL decreased significantly. Therefore, it is speculated that the ALL deficiency can be a reason for persistent rotational instability after ACL reconstruction [13].

The isometry of the ALL was measured by Dodds et al. [7], by threading a suture along the ligament fibers, attaching it to the moving tibia and then measuring the changes of the separation distance between the attachments using a transducer. It was shown that the ALL was not isometric, but was close to being isometric from 0 to 60° knee flexion. Internal tibial rotation increased the length between the attachments, and external rotation reduced it. When the knee was in extension, tibial rotations in response to 5 Nm torque were not large enough to cause significant change in the length of the ALL. However, internal tibial rotation increased the mean length between the ALL attachments from 3.6 mm (SD 0.7; 1.5–5.7) at 30° (p = 0.003) to 9.9 mm (SD 1.4; 5.7–14.2) at 90° of flexion of the knee. Imbert et al. [14] investigated isometric characteristics of the ALL in a cadaveric navigation study and found that ALL is not isometric at any of the femoral insertion locations but had different length change patterns during knee flexion and internal tibial rotation at 90°. However, they found that the proximal and posterior to epicondyle femoral position is favorable to being isometry.

#### **4. Injury**

*Knee Surgery - Reconstruction and Replacement*

**2. Anatomy**

indications and techniques of ALL reconstruction.

2.09 mm in males and 1.09 mm in females [9].

angles; however, the biomechanical role of ALL is still the subject of debate [3, 4]. This chapter reviews the main features related to ALL and focuses on the current

The anatomy of the ALL has been investigated by several authors in order to accurately identify the features of the structure. There has been some debate regarding the exact attachments of the ligament; however, it is generally accepted that the ALL is a distinctive triangular, anterolateral structure under the iliotibial band (ITB). Investigations of the anatomy of the ALL in several cadavers have revealed variability of the structure particularly for the femoral attachment. The femoral origin is located at the lateral femoral epicondyle (LFE) at either the identical position of the origin of the fibular collateral ligament (FCL) or just posterior and proximal to it with the average width at this point 11.85 mm [5]. The ALL then runs distally by overlapping the proximal portion of the lateral collateral ligament, and some fibers of the ALL are attached to the lateral meniscus and the anterolateral capsule at the level of knee joint. The majority of the fibers continue to run distally and attach midway between the tip of the fibular head and GT (**Figure 1**). The tibial attachment is 12.2 ± 3.0 mm width and is centered 21.6 mm posterior to Gerdy's tubercle, and 4–10 mm far from the joint line [1, 6–8]. The mean length of the structure has been measured between 34 and 59 mm from its femoral origin to tibial attachment [7, 8]. The thickness of ALL also varies and has been measured as

Zens et al. [10] found that the isolated ALL had an ultimate tensile strength of 50 ± 15 N, at a strain of 36 ± 4%. With a mean cross-sectional area of only 1.54 mm2

*Anterolateral ligament anatomy (ITB: iliotibial band, ALL: anterolateral ligament, FH: fibular head, GT:* 

the ultimate tensile stress was 33 ± 4 MPa and the overall stiffness was 4.2 N/ mm extension. However, Kennedy et al. [11] reported that the ALL had a tensile

**28**

**3. Biomechanics**

*Gerdy's tubercle, and LCL: lateral collateral ligament).*

**Figure 1.**

Injury to the ALL is most commonly associated with a concomitant tear of the ACL. In a retrospective MRI study, Claes et al. [2] analyzed 206 ACL injured knees and found 78.8% radiological ALL abnormalities. Most of the ALL abnormalities were found to be situated in the distal part of the ligament (77.8%), whereas 20.4% of the injuries were proximal and only 1.8% knees were diagnosed with a bony ALL avulsion. Ferretti et al. [15] exposed the lateral knee compartments of 60 patients undergoing ACLR and found several lesion types of the ALL injuries including macroscopic hemorrhage extending to the anterolateral capsule (32%) or to the posterolateral capsule (27%), complete transverse tear of the ALL near its tibial insertion (22%), and a bony tibial avulsion (Segond fracture) (10%). In a retrospective MRI study, Gurpinar et al. found 65.2% ALL injury in patients underwent ACL surgery who were diagnosed with isolated ACL injury previously [13]. In a similar study, van Dyck et al. [16] found ALL abnormalities in 46% of 90 knee MRIs of patients with an acute ACL rupture. Furthermore, they found that these patients were more likely to have a lateral meniscal tear, collateral ligament injury, or osseous injury compared with patients with an intact ALL.

After re-discovery of ALL, Segond fractures, which were previously considered as a diagnostic clue for ACL injury, are classified as ALL equivalent injuries [17]. Porrino et al. [18] evaluated 20 knee MRIs with a Segond fracture and found that the ALL was attached to the fracture fragment in all but one case limited by anatomic distortion. Claes et al. [17] also suggested that the Segond fracture is actually

,

a bony avulsion of the ALL. However, Shaikh et al. [19] claimed that ITB and lateral capsule attached to the Segond fracture in 94% of the patients and Segond fracture is not merely an ALL avulsion but the avulsion of the anterolateral complex.

On the other hand, anterolateral injuries and instability can also occur in the ACL intact states. Gottsegen et al. [20] and DeLee et al. [21] reported the Segond fracture combined to popliteal tendon avulsion and iliotibial band avulsion. Wharton et al. [26] published a case report in which the Segond fracture was combined to posterolateral ligament injury without ACL rupture. Furthermore, Ferreira reported an absolute isolated Segond fracture.

#### **5. Diagnosis**

Diagnosing ALL lesions can be difficult since no specific clinical tests have been validated for the diagnosis of ALL injuries. To achieve an impeccable diagnosis, meticulous clinical examination and appropriate evaluation of the radiographic and MRI imaging are necessary. Since ALL is highly associated with ACL injury, patients subjected to trauma mechanisms similar to an isolated ACL injury such as contact and noncontact injuries involving early flexion, dynamic valgus, and internal rotation should also be suspected for ALL injury. Anterior drawer and Lachman tests can be positive due to the concomitant ACL injury. However, since ALL is primarily responsible for rotational stability, pivot-shift test is considered to be the most reliable test to evaluate ALL integrity. Monaco et al. [27] demonstrated that a grade III pivot shift is only seen in the absence of both the ACL and ALL in vitro. However, the potential confusing factors of a high-grade pivot shift, such as a lateral meniscus or root tear, ITB injury, or general hyperlaxity should be assessed [28, 29].

Segond fracture is also considered to be ALL avulsion, and therefore, it can be assumed that symptoms related to a Segond fracture may be present in ALL injury including provoked pain on palpation of the lateral tibia or increased laxity in varus stress. On examination, the lateral compartment of the knee should be carefully evaluated, and the integrity of the cruciate and collateral ligaments should be examined too. However, in the acute phase, diagnosis can be challenging and evaluation should be repeated in subacute and chronic phases after swelling and pain has decreased.

#### **6. Surgical indications**

The optimal ACL reconstruction is still a debate in orthopedic research, and persistent rotatory instability has been reported up to 25% of cases after an isolated ACL reconstruction procedure [30]. Some studies found that an isolated ACL reconstruction can control the translational instability, but is insufficient to restore the normal rotational stability. In addition, the persistent rotatory instability does not only cause difficulties with pivoting sports, but also can cause secondary meniscal and cartilaginous problems [31]. Furthermore, younger and higher-level athletes with rotational instability can be vulnerable to re-ruptures. Therefore, combining a lateral extra-articular procedure with an intra-articular reconstruction for the treatment of ACL injury emerged, with the aim of decreasing rotational instability. However, long-term results of ALL reconstruction are not known and have not been suggested as a standard procedure with ACL reconstruction. Despite this, additional ALL reconstruction has been recommended in patients with grade III pivot shift or Segond fracture and athletes practicing of sports with pivot movements [32–34]. In addition ACL revision, subjective rotational looseness, and Telos

**31**

*Decision-Making for ALL Reconstruction and Surgical Techniques*

value >10 mm are also considered as indicative of ALL reconstruction associated with ACL reconstruction [35]. Some surgeons also suggested ALL reconstruction in cases of chronic ACL reconstruction, high level of sports activity, and radiographic

Recently the ALL Expert Group [37] proposed a decision tree for the management of ACL ruptures and recommended ALL reconstruction for patients who present at least: (1) decisive criteria for increased risk of secondary ACL rupture or postoperative residual positive pivot shift or (2) secondary criteria for increased risk of secondary ACL rupture or postoperative residual positive pivot shift including history, clinical or imaging signs, or patient profile. However, literature still lacks good-quality randomized studies and more studies are needed to prove these

Wytrykowski et al. [38] performed a cadaveric study to compare the biomechanical properties of the ALL, gracilis, and IT band. The gracilis was found to have six times the stiffness of the ALL (131.7 vs. 21 N/mm) and had the highest maximum load to failure (200.7 vs. 141 N). The mechanical properties of the IT band (stiffness, 39.9 N/mm; maximum load to failure, 161.1 N) most closely resembled those of the ALL. However, many authors have published techniques using a gracilis graft for ALL reconstruction and a tripled semitendinosus auto- or allograft or quadrupled semitendinosus autograft with all-inside technique for the reconstruction of ACL [39–41]. The use of polyester tape [42] or a single-bundle semitendinosus auto- or allograft has also been described in the literature [43]. In our clinic, we use gracilis graft for ALL reconstruction, and for the ACL, we use quadriceps autograft,

On the tibia, the anatomical landmarks are the center of the fibula head, the center of Gerdy's tubercle, and joint line (**Figure 2a**). We use the midpoint between Gerdy's tubercle and the fibula at 5–10 mm below the lateral joint line for the site of tibial fixation. We make a stab incision 5–10 mm below the joint line, halfway between the center of Gerdy's tubercle and the fibula head (**Figure 2b**). Helito et al. [44] have described the radiographic landmarks to determine this location. They choose a point around 7 mm below the tibial plateau on the AP view and around 50% of the plateau length on the lateral view [39]. Similar tibial attachment points have been used by many authors; however, some surgeons used two attachment points, and therefore, they used one point just anterior to the fibular head and

Since the origin of the femoral insertion of the ALL varies, the location of femoral fixation during ALLR is a debate. Many authors [40, 46, 47] described a fixation at a point posterior and superior to the lateral femoral epicondyle; however, some [41, 42] described a fixation slightly anterior to the lateral epicondyle. As a radiological reference point, Helito et al. used Blumensaat's line and identified the femoral attachment at approximately halfway along Blumensaat's line from the anterior edge of the femoral condyle [44]. Kennedy et al. used the intersection of two lines: one was the parallel extension of the posterior femoral cortex and the second line was drawn perpendicularly to the first line and intersecting the most

*DOI: http://dx.doi.org/10.5772/intechopen.86398*

lateral femoral notch sign [36].

findings.

**7. Reconstruction**

**7.1 Graft type and preparation**

tripled semitendinosus, or allograft.

**7.2 Femoral and tibial origins and fixation**

second point posterior to the Gerdy's tubercle [45].

*Decision-Making for ALL Reconstruction and Surgical Techniques DOI: http://dx.doi.org/10.5772/intechopen.86398*

value >10 mm are also considered as indicative of ALL reconstruction associated with ACL reconstruction [35]. Some surgeons also suggested ALL reconstruction in cases of chronic ACL reconstruction, high level of sports activity, and radiographic lateral femoral notch sign [36].

Recently the ALL Expert Group [37] proposed a decision tree for the management of ACL ruptures and recommended ALL reconstruction for patients who present at least: (1) decisive criteria for increased risk of secondary ACL rupture or postoperative residual positive pivot shift or (2) secondary criteria for increased risk of secondary ACL rupture or postoperative residual positive pivot shift including history, clinical or imaging signs, or patient profile. However, literature still lacks good-quality randomized studies and more studies are needed to prove these findings.

#### **7. Reconstruction**

*Knee Surgery - Reconstruction and Replacement*

reported an absolute isolated Segond fracture.

**5. Diagnosis**

decreased.

**6. Surgical indications**

a bony avulsion of the ALL. However, Shaikh et al. [19] claimed that ITB and lateral capsule attached to the Segond fracture in 94% of the patients and Segond fracture

On the other hand, anterolateral injuries and instability can also occur in the ACL intact states. Gottsegen et al. [20] and DeLee et al. [21] reported the Segond fracture combined to popliteal tendon avulsion and iliotibial band avulsion. Wharton et al. [26] published a case report in which the Segond fracture was combined to posterolateral ligament injury without ACL rupture. Furthermore, Ferreira

Diagnosing ALL lesions can be difficult since no specific clinical tests have been validated for the diagnosis of ALL injuries. To achieve an impeccable diagnosis, meticulous clinical examination and appropriate evaluation of the radiographic and MRI imaging are necessary. Since ALL is highly associated with ACL injury, patients subjected to trauma mechanisms similar to an isolated ACL injury such as contact and noncontact injuries involving early flexion, dynamic valgus, and internal rotation should also be suspected for ALL injury. Anterior drawer and Lachman tests can be positive due to the concomitant ACL injury. However, since ALL is primarily responsible for rotational stability, pivot-shift test is considered to be the most reliable test to evaluate ALL integrity. Monaco et al. [27] demonstrated that a grade III pivot shift is only seen in the absence of both the ACL and ALL in vitro. However, the potential confusing factors of a high-grade pivot shift, such as a lateral meniscus

or root tear, ITB injury, or general hyperlaxity should be assessed [28, 29].

Segond fracture is also considered to be ALL avulsion, and therefore, it can be assumed that symptoms related to a Segond fracture may be present in ALL injury including provoked pain on palpation of the lateral tibia or increased laxity in varus stress. On examination, the lateral compartment of the knee should be carefully evaluated, and the integrity of the cruciate and collateral ligaments should be examined too. However, in the acute phase, diagnosis can be challenging and evaluation should be repeated in subacute and chronic phases after swelling and pain has

The optimal ACL reconstruction is still a debate in orthopedic research, and persistent rotatory instability has been reported up to 25% of cases after an isolated ACL reconstruction procedure [30]. Some studies found that an isolated ACL reconstruction can control the translational instability, but is insufficient to restore the normal rotational stability. In addition, the persistent rotatory instability does not only cause difficulties with pivoting sports, but also can cause secondary meniscal and cartilaginous problems [31]. Furthermore, younger and higher-level athletes with rotational instability can be vulnerable to re-ruptures. Therefore, combining a lateral extra-articular procedure with an intra-articular reconstruction for the treatment of ACL injury emerged, with the aim of decreasing rotational instability. However, long-term results of ALL reconstruction are not known and have not been suggested as a standard procedure with ACL reconstruction. Despite this, additional ALL reconstruction has been recommended in patients with grade III pivot shift or Segond fracture and athletes practicing of sports with pivot movements [32–34]. In addition ACL revision, subjective rotational looseness, and Telos

is not merely an ALL avulsion but the avulsion of the anterolateral complex.

**30**

#### **7.1 Graft type and preparation**

Wytrykowski et al. [38] performed a cadaveric study to compare the biomechanical properties of the ALL, gracilis, and IT band. The gracilis was found to have six times the stiffness of the ALL (131.7 vs. 21 N/mm) and had the highest maximum load to failure (200.7 vs. 141 N). The mechanical properties of the IT band (stiffness, 39.9 N/mm; maximum load to failure, 161.1 N) most closely resembled those of the ALL. However, many authors have published techniques using a gracilis graft for ALL reconstruction and a tripled semitendinosus auto- or allograft or quadrupled semitendinosus autograft with all-inside technique for the reconstruction of ACL [39–41]. The use of polyester tape [42] or a single-bundle semitendinosus auto- or allograft has also been described in the literature [43]. In our clinic, we use gracilis graft for ALL reconstruction, and for the ACL, we use quadriceps autograft, tripled semitendinosus, or allograft.

#### **7.2 Femoral and tibial origins and fixation**

On the tibia, the anatomical landmarks are the center of the fibula head, the center of Gerdy's tubercle, and joint line (**Figure 2a**). We use the midpoint between Gerdy's tubercle and the fibula at 5–10 mm below the lateral joint line for the site of tibial fixation. We make a stab incision 5–10 mm below the joint line, halfway between the center of Gerdy's tubercle and the fibula head (**Figure 2b**). Helito et al. [44] have described the radiographic landmarks to determine this location. They choose a point around 7 mm below the tibial plateau on the AP view and around 50% of the plateau length on the lateral view [39]. Similar tibial attachment points have been used by many authors; however, some surgeons used two attachment points, and therefore, they used one point just anterior to the fibular head and second point posterior to the Gerdy's tubercle [45].

Since the origin of the femoral insertion of the ALL varies, the location of femoral fixation during ALLR is a debate. Many authors [40, 46, 47] described a fixation at a point posterior and superior to the lateral femoral epicondyle; however, some [41, 42] described a fixation slightly anterior to the lateral epicondyle. As a radiological reference point, Helito et al. used Blumensaat's line and identified the femoral attachment at approximately halfway along Blumensaat's line from the anterior edge of the femoral condyle [44]. Kennedy et al. used the intersection of two lines: one was the parallel extension of the posterior femoral cortex and the second line was drawn perpendicularly to the first line and intersecting the most

**Figure 2.** *Step-by-step anterolateral ligament reconstruction.*

posterior aspect of Blumensaat's line [11]. In our clinic, we make a 5–10 mm incision just proximal to the epicondyle, and after dividing the ITB, we insert the drill pin slightly proximal and posterior to the lateral epicondyle (**Figure 1c** and **d**).

After inserting femoral and tibial pin guides, the passing suture is placed under the ITB around the femoral wire and tibial wires. The knee is then moved through the full range of motion (**Figure 1d**). The isometry assessment is made to be sure that the graft will not tighten in flexion and will be tight in extension. If the suture tightens in flexion, the femoral socket may be too distal or anterior.

After the isometry test, the graft is passed under the ITB and fixed with interference screws or anchors on both sides, while the knee is 30° flexed and at neutral rotation (**Figure 2**). However, fixation in full extension at 45–60° of flexion or fixation at 60–90° of flexion have also been described in the literature [39, 40, 47]. Different surgical techniques and indications are summarized in **Table 1**.

#### **8. Postoperative rehabilitation**

The plaster cast immobilization or bracing were popular in the historical literature when ACL and lateral extra-articular procedures were performed together [49]. However, use of brace is much less common in current practice. Many authors recommend that rehabilitation after an additional ALL reconstruction should be carried out in a similar way compared to isolated ACL rehabilitation. An early aggressive rehabilitation program can be applied. Emphasis should be placed on achieving symmetrical full knee extension, decreasing knee joint effusion, and quadriceps activation early in the rehabilitation process. Passive flexion and patellar mobilization, avoiding eccentric quadriceps contraction, should also be performed. Weight bearing as tolerated is recommended immediately following surgery to promote knee extension and hinder quadriceps inhibition.

**33**

**Author/ year** Helito et al. [39] Smith et al. [41]

Sonnery- Cottet et al.

Segond fractures, chronic ACL tears, grade III pivot shift, high-level or pivot sports participation, lateral femoral notch sign

Gracilis

Proximal and posterior to lateral epicondyle

Site of Segond fracture, at tibial footprint of ALL

4.75 or 5.5 mm interference screw

Not reported

Asymmetry of lateral plateau with internal rotation, grade II/III pivot shift, ALL tear on MRI, Segond fractures

Gracilis

8 mm posterosuperiorly from lateral epicondyle

9–13 mm distal to lateral joint line

Interference screw 2 mm larger than tunnel

45–60° flexion

Grade III pivot shift, multiple ACL reconstructions

Semitendinosus

4.7 mm proximal and

Midway between the

7 × 28-mm

30° flexion

interference screw

Gerdy's tubercle and

anterior margin fibular

head (9.5 mm distal to

joint line)

Midpoint between the

Cortical

30° flexion

suspension button

Gerdy's tubercle and

the fibular head

One point just anterior

Tibial tunnel no

Full

extension

fixation femoral

side ACL graft

ethibond

to the fibular head and

second posterior to

Gerdy's tubercle

posterior to FCL insertion

site

with residual laxity, clinically significant instability

after ACL reconstruction

Chahla

et al. [43]

Wagih and

Grade III pivot-shift examination

Polyester tape

Anterior and distal to

lateral femoral condyle

Elguindy

[42]

Saithna

Young age (<20 years old). Participation in pivoting

Gracilis

Just proximal and

posterior to the lateral

epicondyle

sports or a high-demand athlete, high-grade pivot

shift on examination, lateral femoral notch sign on

preoperative imaging, Segond fracture. Revision ACL

reconstruction. Chronic (>12 months) ACL injury

et al. [45]

[47] Ferreira et al. [40]

Marked laxity on examination under anesthesia

Gracilis

High-grade pivot-shift examination, ACL revision without apparent cause for failure

**Reported indications**

**Graft types**

Gracilis

3–4 mm below the halfway point on the Blumensaat's line in the AP direction

5–10 mm below the lateral tibial plateau

Inference screw 1 size greater than tunnel diameter

60–90° of flexion

5.5-mm suture anchors

30° of flexion

Anterior to lateral femoral epicondyle

Midway between fibular head and the Gerdy's tubercle, 11 mm distal to joint line

**Femoral fixation point**

**Tibial fixation point**

**Fixation types**

**Fixation angle**

*Decision-Making for ALL Reconstruction and Surgical Techniques*

*DOI: http://dx.doi.org/10.5772/intechopen.86398*


#### *Decision-Making for ALL Reconstruction and Surgical Techniques DOI: http://dx.doi.org/10.5772/intechopen.86398*

*Knee Surgery - Reconstruction and Replacement*

posterior aspect of Blumensaat's line [11]. In our clinic, we make a 5–10 mm incision just proximal to the epicondyle, and after dividing the ITB, we insert the drill pin slightly proximal and posterior to the lateral epicondyle (**Figure 1c** and **d**).

After inserting femoral and tibial pin guides, the passing suture is placed under the ITB around the femoral wire and tibial wires. The knee is then moved through the full range of motion (**Figure 1d**). The isometry assessment is made to be sure that the graft will not tighten in flexion and will be tight in extension. If the suture

After the isometry test, the graft is passed under the ITB and fixed with interference screws or anchors on both sides, while the knee is 30° flexed and at neutral rotation (**Figure 2**). However, fixation in full extension at 45–60° of flexion or fixation at 60–90° of flexion have also been described in the literature [39, 40, 47].

tightens in flexion, the femoral socket may be too distal or anterior.

promote knee extension and hinder quadriceps inhibition.

**8. Postoperative rehabilitation**

*Step-by-step anterolateral ligament reconstruction.*

Different surgical techniques and indications are summarized in **Table 1**.

The plaster cast immobilization or bracing were popular in the historical literature when ACL and lateral extra-articular procedures were performed together [49]. However, use of brace is much less common in current practice. Many authors recommend that rehabilitation after an additional ALL reconstruction should be carried out in a similar way compared to isolated ACL rehabilitation. An early aggressive rehabilitation program can be applied. Emphasis should be placed on achieving symmetrical full knee extension, decreasing knee joint effusion, and quadriceps activation early in the rehabilitation process. Passive flexion and patellar mobilization, avoiding eccentric quadriceps contraction, should also be performed. Weight bearing as tolerated is recommended immediately following surgery to

**32**

**Figure 2.**


### **Table 1.**

**35**

*Decision-Making for ALL Reconstruction and Surgical Techniques*

To date, only few studies reported the clinical outcomes of ALL reconstruction since the rediscovery of this ligament [32, 33, 36, 50]. In a retrospective case series, Sonnery-Cottet et al. [36] evaluated 92 patients at a minimum 2-year follow-up after concomitant ACL and ALL reconstruction. Compared with the preoperative assessment, the follow-up showed significant improvements in Lysholm score, subjective IKDC score, and objective IKDC score. Pivot-shift results were also significantly improved; however, this study did not have a control group.

In a prospective comparative study of 502 patients, Sonnery et al. found lower graft rupture rate with combined ALL-ACL reconstruction technique in a high-risk population, compared to the isolated ACL reconstructions that used a bone-patellar tendon-bone graft or a quadrupled hamstring tendon graft [33]. Another randomized study showed an improvement in knee laxity measured using a KT-1000 arthrometer in patients with combined ACL and ALL reconstructions compared to patients with isolated ACL reconstructions; however, the other measured parameters did not differ significantly [32]. Recently, Helito et al. [50] evaluated the results of combined ACL-ALL reconstruction with isolated ACL reconstruction in 101 chronic ACL injuries. Regarding functional outcome scores, they found better results on both the IKDC and the Lysholm evaluations in combined ACL-ALL reconstruction group. In addition, patients in the ACL-ALL reconstruction group had better KT-1000 evaluation and a lower pivot-shift rate at physical examination. Although the results of the recent studies are promising, indications for ALL reconstruction are not identical in these studies and additional studies are needed to

In conclusion, it is commonly accepted that the ALL is a distinctive structure that originates from proximal and posterior to the femoral epicondyle, attaches slightly posterior to the Gerdy's tubercle, and functions as a secondary stabilizer to internal rotation. In addition, it has been reported that it has a crucial role in preventing pivot-shift phenomenon. However, there is a lack of evidence supporting that it can be a reason for persistent pivot shift after ACL reconstructions [13]. Although the results of the recent studies reporting the outcomes of ALL reconstruction are promising, the total volume of literature on this topic is limited and composed of low-quality evidence. More studies with longer follow-up times are, therefore, needed to provide the convincing clinical evidence for the favor of concomitant ACL and ALL procedures. In addition, despite the lack of clear evidence for an increase in lateral compartment osteoarthritis after concomitant procedures, compression in the lateral compartment seems to be a concern and was regarded as

a reason to abandon concomitant lateral procedures historically [51–53].

There is no support funding for the publication.

The author declares that no conflict of interest exists.

*DOI: http://dx.doi.org/10.5772/intechopen.86398*

**9. Clinical outcomes**

confirm these results.

**Acknowledgements**

**Conflict of interest**

**10. Conclusions**

*Indications, femoral and tibial fixation points, and fixation materials and angles reported in the literature.*

#### **9. Clinical outcomes**

*Knee Surgery - Reconstruction and Replacement*

**34**

**Author/**

**Reported indications**

**Graft types**

Gracilis

Posterior and proximal to

One point just anterior

SwiveLock anchor

Full

extension

to the fibular head and

second posterior to

Gerdy's tubercle

the lateral epicondyle

**Femoral fixation point**

**Tibial fixation point**

**Fixation types**

**Fixation** 

**angle**

**year**

Delaloye

ACL repair

et al. [48]

**Table 1.**

*Indications, femoral and tibial fixation points, and fixation materials and angles reported in the literature.*

To date, only few studies reported the clinical outcomes of ALL reconstruction since the rediscovery of this ligament [32, 33, 36, 50]. In a retrospective case series, Sonnery-Cottet et al. [36] evaluated 92 patients at a minimum 2-year follow-up after concomitant ACL and ALL reconstruction. Compared with the preoperative assessment, the follow-up showed significant improvements in Lysholm score, subjective IKDC score, and objective IKDC score. Pivot-shift results were also significantly improved; however, this study did not have a control group.

In a prospective comparative study of 502 patients, Sonnery et al. found lower graft rupture rate with combined ALL-ACL reconstruction technique in a high-risk population, compared to the isolated ACL reconstructions that used a bone-patellar tendon-bone graft or a quadrupled hamstring tendon graft [33]. Another randomized study showed an improvement in knee laxity measured using a KT-1000 arthrometer in patients with combined ACL and ALL reconstructions compared to patients with isolated ACL reconstructions; however, the other measured parameters did not differ significantly [32]. Recently, Helito et al. [50] evaluated the results of combined ACL-ALL reconstruction with isolated ACL reconstruction in 101 chronic ACL injuries. Regarding functional outcome scores, they found better results on both the IKDC and the Lysholm evaluations in combined ACL-ALL reconstruction group. In addition, patients in the ACL-ALL reconstruction group had better KT-1000 evaluation and a lower pivot-shift rate at physical examination. Although the results of the recent studies are promising, indications for ALL reconstruction are not identical in these studies and additional studies are needed to confirm these results.

#### **10. Conclusions**

In conclusion, it is commonly accepted that the ALL is a distinctive structure that originates from proximal and posterior to the femoral epicondyle, attaches slightly posterior to the Gerdy's tubercle, and functions as a secondary stabilizer to internal rotation. In addition, it has been reported that it has a crucial role in preventing pivot-shift phenomenon. However, there is a lack of evidence supporting that it can be a reason for persistent pivot shift after ACL reconstructions [13]. Although the results of the recent studies reporting the outcomes of ALL reconstruction are promising, the total volume of literature on this topic is limited and composed of low-quality evidence. More studies with longer follow-up times are, therefore, needed to provide the convincing clinical evidence for the favor of concomitant ACL and ALL procedures. In addition, despite the lack of clear evidence for an increase in lateral compartment osteoarthritis after concomitant procedures, compression in the lateral compartment seems to be a concern and was regarded as a reason to abandon concomitant lateral procedures historically [51–53].

#### **Acknowledgements**

There is no support funding for the publication.

#### **Conflict of interest**

The author declares that no conflict of interest exists.

*Knee Surgery - Reconstruction and Replacement*

#### **Author details**

Tahsin Gurpinar University of Health Sciences, Istanbul Research and Education Hospital, Istanbul, Turkey

\*Address all correspondence to: tahsingurpinar@msn.com

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

**37**

*Decision-Making for ALL Reconstruction and Surgical Techniques*

Knee Surgery, Sports Traumatology, Arthroscopy. 2012;**20**(1):147-152

[9] Daggett M, Busch K, Sonnery-Cottet B. Surgical dissection of the anterolateral ligament. Arthroscopy Techniques. 2016;**5**(1):e185-e188

[10] Zens M, Feucht MJ, Ruhhammer J, Bernstein A, Mayr HO, Südkamp NP, et al. Mechanical tensile properties of the anterolateral ligament. Journal of Experimental Orthopaedics. 2015;**2**(1):7

[11] Kennedy MI, Claes S, Fuso FA, Williams BT, Goldsmith MT, Turnbull TL, et al. The anterolateral ligament: An anatomic, radiographic, and biomechanical analysis. The American Journal of Sports Medicine.

[12] Ruiz N, Filippi GJ, Gagnière B, Bowen M, Robert HE. The comparative role of the anterior cruciate ligament and anterolateral structures in controlling passive internal rotation of the knee: A biomechanical study. Arthroscopy.

[13] Gürpınar T, Polat B, Polat AE, Mutlu İ, Tüzüner T. Is anterolateral ligament rupture a reason for persistent rotational instability after anterior cruciate ligament reconstruction? The

[14] Imbert P, Lutz C, Daggett M, Niglis L, Freychet B, Dalmay F, et al. Isometric characteristics of the anterolateral ligament of the knee: A cadaveric navigation study. Arthroscopy.

[15] Ferretti A, Monaco E, Fabbri M, Maestri B, De Carli A. Prevalence and classification of injuries of

anterolateral complex in acute anterior cruciate ligament tears. Arthroscopy.

Knee. 2018;**25**(6):1033-1039

2016;**32**(10):2017-2024

2017;**33**(1):147-154

2015;**43**(7):1606-1615

2016;**32**(6):1053-1062

*DOI: http://dx.doi.org/10.5772/intechopen.86398*

[1] Claes S, Vereecke E, Maes M, Victor J, Verdonk P, Bellemans J. Anatomy of the anterolateral ligament of the knee. Journal of Anatomy.

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[2] Claes S, Bartholomeeusen S, Bellemans J. High prevalence of anterolateral ligament abnormalities in magnetic resonance images of anterior cruciate ligament-injured knees. Acta Orthopaedica Belgica. 2014;**80**(1):45-49

[3] Parsons EM, Gee AO, Spiekerman C, Cavanagh PR. The biomechanical function of the anterolateral ligament of the knee. The American Journal of Sports Medicine. 2015;**43**(3):669-674

[4] Guenther D, Rahnemai-Azar AA, Fu FH, Debski RE. The biomechanical function of the anterolateral ligament of the knee: Letter to the editor. The American Journal of Sports Medicine.

[5] Daggett M, Ockuly AC, Cullen M, Busch K, Lutz C, Imbert P, et al. Femoral origin of the anterolateral ligament: An anatomic analysis. Arthroscopy. 2016;**32**(5):835-841

[6] Caterine S, Litchfield R, Johnson M, Chronik B, Getgood A. A cadaveric study of the anterolateral ligament: Re-introducing the lateral capsular ligament. Knee Surgery, Sports Traumatology, Arthroscopy.

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**36**

**Author details**

Tahsin Gurpinar

Turkey

provided the original work is properly cited.

\*Address all correspondence to: tahsingurpinar@msn.com

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

University of Health Sciences, Istanbul Research and Education Hospital, Istanbul,

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**41**

Section 3

Knee Replacement
