**2. Current uses of Ultrasound and MRI**

Acute muscular strain injuries are frequently found in sports, at both amateur and competitive level, so much so that diagnostic imaging has acquired primary importance in identifying the trauma, assessing the damage, estimating possible complications and predicting recovery. Ultrasound and MRI play an important role in the study of muscle injuries owing to their ability to identify lesions effectively, which is closely related to the presence of oedema in the damaged muscle. [1]

US and MRI play an important role in the study of muscle injuries owing to their ability to identify lesions effectively, which is closely related to the presence of oedema in the damaged

Diagnostic Imaging in Muscle Injury http://dx.doi.org/10.5772/56472 99

Literature contains no generally accepted classification of muscle traumas, and classification of minor traumas, in which imaging patterns are often identical, is even more complex.

In our experience, only a combination of imaging and accurate clinical examination makes it

In our study, we observed only 26 minor traumas out of a total of 81 traumas (32%). The small number of minor traumas observed reflects the vagueness of their clinical symptoms rather than their rarity. Ultrasound sensitivity to minor traumas is much lower than that obtained for major traumas (76.92% vs. 92.72%). This is because Ultrasound findings in minor traumas are vague and indistinct if the oedema is small. In our study, the lowest Ultrasound sensitivity

Studying 40 patients with DOMS, Dierking et al. observed that ultrasound had low sensitivity

Although MRI correctly detected the muscle oedema in seven of our patients with DOMS, the pattern was non-specific and the correct diagnosis required integration with laboratory

De Smet states that MRI is reliable only if it is preceded by a thorough clinical assessment that enables selection of the most appropriate sequences and scan planes, and observed specificity and sensitivity values of 80% and 83%, respectively, for diagnosis of contractures and length‐ ening. This may also be correlated to the presence of considerable muscle oedema, which facilitates lesion identification. In such cases, Ultrasound demonstrates diffuse hypoechoge‐

Hashimoto et al. suggest the use of very-high-frequency transducers to detect minor le‐ sions.Ultrasound sensitivity increases slightly in mild contusions. In these cases, as the trauma

In our experience, the Ultrasound imaging pattern of small contusions does not differ much from that of other minor traumas; in all cases, it shows muscle oedema without interruption of the continuity of muscle fibres. Differentiation was only possible on the basis of the patient's

As regards major traumas, Ultrasound had 84% sensitivity in identifying muscle strain. The

Significant differences were observed between third-degree muscle strains (which are readily

has an external origin, the sonographer is guided by knowledge of the site of impact.

muscle. [1]

MRI is regarded as the gold standard. [3]

possible to achieve a correct diagnosis.

values were recorded for DOMS. [4]

findings such as creatine-kinase assay.

nicity with displacement of the tertiary bundles. [6]

extent of tissue alterations affects the Ultrasound pattern.

detected) and first-degree muscle strains. In two cases of false

in detecting the complaint. [5]

history.

The aim of our work is to analyse and compare the diagnostic value of ultrasound and MRI in terms of sensitivity, and recommend the best route to follow when studying muscular injuries.

First and foremost, advances in technology have dramatically improved image quality and nowadays a physician can easily prescribe either an MRI or an echography.

Although ultrasound has been used to evaluate the musculoskeletal system for approximately 25 years and despite the increasingly frequent use of MRI, there has been a renewed interest in Ultrasound for several reasons. The spatial resolution of Ultrasound exceeds the resolution obtainable with magnetic resonance (MR) imaging without the use of small surface coils and specific imaging parameters. For example, commercially available transducers with frequen‐ cies of 9 MHz to 15 MHz produce in-plane resolutions of 200 mm to 450 mm and section thicknesses of 0.5 mm to 1 mm. The resolution of sonographic imaging with standard highfrequency transducers allows visualization of individual neuronal fascicles in peripheral nerves.

Another reason for the increased interest in musculoskeletal Ultrasound is an understanding of its role in connection with MR imaging. MR imaging is valuable when the global assessment of a joint requires evaluation of the muscles, tendons, cartilage, and bone marrow. Ultrasound, however, can produce similar results when a focused evaluation of muscle, tendon, and joint recesses is needed. Frequently this can be performed at a lower cost and with less delay when compared with MR imaging.

More importantly, however, there are several applications where Ultrasound outperforms MR imaging. One deserving emphasis is the use of dynamic imaging with musculoskeletal Ultrasound.

Dynamic imaging is very helpful when differentiating full-thickness from partial-thickness tendon tears because tendon retraction indicates full-thickness tear. Additionally, there are several conditions where muscle, tendon, and nerve subluxation or dislocation only occur with specific extremity positions or movements. These abnormal subluxations or dislocations reduce in neutral position and remain undetected with routine MR imaging.

One last advantage of Ultrasound over MR imaging is the ability to focus the examination precisely at the region of symptoms and obtain imaging which is directly correlated to the patient's complaints. This correspondence is invaluable for a physician from a diagnostic perspective. [2]

US and MRI play an important role in the study of muscle injuries owing to their ability to identify lesions effectively, which is closely related to the presence of oedema in the damaged muscle. [1]

MRI is regarded as the gold standard. [3]

**2. Current uses of Ultrasound and MRI**

damaged muscle. [1]

98 Muscle Injuries in Sport Medicine

nerves.

Ultrasound.

perspective. [2]

compared with MR imaging.

Acute muscular strain injuries are frequently found in sports, at both amateur and competitive level, so much so that diagnostic imaging has acquired primary importance in identifying the trauma, assessing the damage, estimating possible complications and predicting recovery. Ultrasound and MRI play an important role in the study of muscle injuries owing to their ability to identify lesions effectively, which is closely related to the presence of oedema in the

The aim of our work is to analyse and compare the diagnostic value of ultrasound and MRI in terms of sensitivity, and recommend the best route to follow when studying muscular injuries.

First and foremost, advances in technology have dramatically improved image quality and

Although ultrasound has been used to evaluate the musculoskeletal system for approximately 25 years and despite the increasingly frequent use of MRI, there has been a renewed interest in Ultrasound for several reasons. The spatial resolution of Ultrasound exceeds the resolution obtainable with magnetic resonance (MR) imaging without the use of small surface coils and specific imaging parameters. For example, commercially available transducers with frequen‐ cies of 9 MHz to 15 MHz produce in-plane resolutions of 200 mm to 450 mm and section thicknesses of 0.5 mm to 1 mm. The resolution of sonographic imaging with standard highfrequency transducers allows visualization of individual neuronal fascicles in peripheral

Another reason for the increased interest in musculoskeletal Ultrasound is an understanding of its role in connection with MR imaging. MR imaging is valuable when the global assessment of a joint requires evaluation of the muscles, tendons, cartilage, and bone marrow. Ultrasound, however, can produce similar results when a focused evaluation of muscle, tendon, and joint recesses is needed. Frequently this can be performed at a lower cost and with less delay when

More importantly, however, there are several applications where Ultrasound outperforms MR imaging. One deserving emphasis is the use of dynamic imaging with musculoskeletal

Dynamic imaging is very helpful when differentiating full-thickness from partial-thickness tendon tears because tendon retraction indicates full-thickness tear. Additionally, there are several conditions where muscle, tendon, and nerve subluxation or dislocation only occur with specific extremity positions or movements. These abnormal subluxations or dislocations

One last advantage of Ultrasound over MR imaging is the ability to focus the examination precisely at the region of symptoms and obtain imaging which is directly correlated to the patient's complaints. This correspondence is invaluable for a physician from a diagnostic

reduce in neutral position and remain undetected with routine MR imaging.

nowadays a physician can easily prescribe either an MRI or an echography.

Literature contains no generally accepted classification of muscle traumas, and classification of minor traumas, in which imaging patterns are often identical, is even more complex.

In our experience, only a combination of imaging and accurate clinical examination makes it possible to achieve a correct diagnosis.

In our study, we observed only 26 minor traumas out of a total of 81 traumas (32%). The small number of minor traumas observed reflects the vagueness of their clinical symptoms rather than their rarity. Ultrasound sensitivity to minor traumas is much lower than that obtained for major traumas (76.92% vs. 92.72%). This is because Ultrasound findings in minor traumas are vague and indistinct if the oedema is small. In our study, the lowest Ultrasound sensitivity values were recorded for DOMS. [4]

Studying 40 patients with DOMS, Dierking et al. observed that ultrasound had low sensitivity in detecting the complaint. [5]

Although MRI correctly detected the muscle oedema in seven of our patients with DOMS, the pattern was non-specific and the correct diagnosis required integration with laboratory findings such as creatine-kinase assay.

De Smet states that MRI is reliable only if it is preceded by a thorough clinical assessment that enables selection of the most appropriate sequences and scan planes, and observed specificity and sensitivity values of 80% and 83%, respectively, for diagnosis of contractures and length‐ ening. This may also be correlated to the presence of considerable muscle oedema, which facilitates lesion identification. In such cases, Ultrasound demonstrates diffuse hypoechoge‐ nicity with displacement of the tertiary bundles. [6]

Hashimoto et al. suggest the use of very-high-frequency transducers to detect minor le‐ sions.Ultrasound sensitivity increases slightly in mild contusions. In these cases, as the trauma has an external origin, the sonographer is guided by knowledge of the site of impact.

In our experience, the Ultrasound imaging pattern of small contusions does not differ much from that of other minor traumas; in all cases, it shows muscle oedema without interruption of the continuity of muscle fibres. Differentiation was only possible on the basis of the patient's history.

As regards major traumas, Ultrasound had 84% sensitivity in identifying muscle strain. The extent of tissue alterations affects the Ultrasound pattern.

Significant differences were observed between third-degree muscle strains (which are readily detected) and first-degree muscle strains. In two cases of false

negative results, Ultrasound underestimated lesions subsequently classified as second-degree injuries by MRI. The reason for such underestimation was that both lesions were located deep in the femoral quadriceps and therefore less amenable to Ultrasound.

In contrast, in the study of deeper muscles, Kolouris and Connell identified a discrepancy between Ultrasound and MRI in the evaluation of hamstring injuries and observed that MRI is more accurate in assessing the extent of injury.These studies confirm that Ultrasound is limited in the study of muscle injury in that its resolution is limited to the tertiary bundle, it is unable to identify pathological alterations to the secondary and primary bundles and myofi‐

Diagnostic Imaging in Muscle Injury http://dx.doi.org/10.5772/56472 101

But Ultrasound (US) technologies are rapidly advancing, offering several refined transducer technologies as well as soft and hardware facilities to improve the potential clinical impact in

Nowadays when using B-mode ultrasound, compound imaging and beam-steering are of help in decreasing anisotropy in tendons and ligaments, which are less well depicted due to their

Doppler imaging has become sensitive in the detection of flow in small vessels and the use of US micro bubble contrast agents (Contrast-enhanced ultrasound –CEUS) improves detection of low-volume blood flow in smaller vessels, by increasing the signal-to-noise ratio and thereby facilitating detection of angiogenetic vessels in inflammatory conditions as for muscular lesion. The use of US blood pool contrast agents enables molecular imaging in real-time, and thus the diagnostic potential of US is expanded, opening up a new field of US applications. Objective quantification of altered tissue (e.g., synovial proliferation) needs further development and might be improved by the use of three-dimensional imaging and software tools such as

Real-time sonoelastography (EUS) is a new development for visualization of tissue elasticity by measurement of tissue displacement in terms of stiffness changes, promising new insights

Image fusion is an exciting development that enables superimposition of CT/MRI data sets on

This technique might be helpful in guiding injections under real-time conditions even in regions less easily accessible by US as, for instance, the axial skeleton, and can additionally provide an interesting tool for teaching MSK imaging and ways to guide interventions. [12] But, as described, MRI has very good sensitivity for the depiction of muscle lesions. Various MRI patterns of muscle injury have been described, usually including oedema-like signal

The importance of the STIR technique in detection of muscle injuries has been stressed by Greco et al., who recognized that subtle abnormalities, not easily seen on long echo T2-weighted images, are highlighted with the STIR technique as the short T1 induces suppression of fat

Imaging of muscular lesions has been greatly improved with the use of the contrast medium (Gadolinium), which grants a better definition of the muscular strain. A proof of this was provided by El-Noueam KI, Schweitzer ME, Bhatia, who described how muscle strain injury

signal and makes the effects of prolonged T1 and T2 on signal intensity additive. [13]

brils, and cannot evaluate deep muscle planes. [11]

the field of musculoskeletal (MSK) imaging.

oblique course.

parametric evaluation.

into tendon disorders.

real-time US scanning.

alterations within torn muscle bundles. [1]

Ultrasound examination enables identification of typical lesions of muscle strains: disconti‐ nuity of tertiary bundles, reactive oedema and haematoma. In first-degree strains, the in‐ volvement of a small number of myofibrils can make it difficult to recognise the lesion with Ultrasound so the use of MRI is necessary. More-severe lesions (second and third degree) with involvement of a larger number of myofibrils, will exhibit a hypoechoic or anechoic haema‐ toma, which can remain localised or extend along the bundles. Immediately after a trauma, the true extent of a lesion may be masked by a hyperechoichaemorrhage whereas Ultrasound done after 48–72 hours will reveal the evolution of the haematoma and the extent of the area affected. [7]

In cases of complete tears of the muscle belly, the retracted muscle bundles have the typical Ultrasound appearance of a bell clapper surrounded by a hypoechoichaematoma. In cases of complete tears of the muscle belly, the retracted muscle bundles have the typical Ultrasound appearance of a bell clapper surrounded by a hypoechoichaematoma. As previously emphas‐ ised, a dynamic examination is fundamental in all cases and particularly in first-degree strains, as it enables detection of the separation and dislocation of tertiary bundles and evaluation of the effective extent of the lesion. [8]

Muscle strains are recognisable at MRI due to changes in muscle volume and composition, variations in signal intensity and pathological alterations of surrounding tissues. [9]

Axial scans allow for comparative examination to detect changes in muscle volume and signal intensity. Coronal or sagittal images along the muscle belly axis make it possible to define the extent of the lesion. [6]

An important finding by Megliola et al. was that in all patients with severe contusion, the haematoma was detected with both Ultrasound and MRI, leading to a sensitivity of 100% for Ultrasound. According to Peetrons, a sonographic classification of major muscle lesions into four different types may be made on the basis of the percentage of muscle involved, but it is essential to distinguish lesions giving rise to haematomas from those causing tearing of muscle fibres only.

Megliola et al. studied 29 patients with severe contusion, and Ultrasound was able not only to locate the haematoma but also to evaluate its extent in total agreement with MRI. Ultrasound has far higher sensitivity for major traumas than for minor traumas.

This is because the ability of Ultrasound to evaluate minor traumas is related to the presence of severe muscle oedema. In major traumas, it can accurately evaluate the extent of the lesion, the percentage of muscle affected, the size of the scar and possible complications. [4]

Bianchi et al. examined 17 patients with acute injury of the rectus femoris with both MRI and Ultrasound. There was concordance between the two techniques in identifying the lesions and evaluating lesion extent. The authors therefore concluded that for lesions of the rectus femoris, a very superficial muscle, Ultrasound should be considered the first-line technique. [10]

In contrast, in the study of deeper muscles, Kolouris and Connell identified a discrepancy between Ultrasound and MRI in the evaluation of hamstring injuries and observed that MRI is more accurate in assessing the extent of injury.These studies confirm that Ultrasound is limited in the study of muscle injury in that its resolution is limited to the tertiary bundle, it is unable to identify pathological alterations to the secondary and primary bundles and myofi‐ brils, and cannot evaluate deep muscle planes. [11]

negative results, Ultrasound underestimated lesions subsequently classified as second-degree injuries by MRI. The reason for such underestimation was that both lesions were located deep

Ultrasound examination enables identification of typical lesions of muscle strains: disconti‐ nuity of tertiary bundles, reactive oedema and haematoma. In first-degree strains, the in‐ volvement of a small number of myofibrils can make it difficult to recognise the lesion with Ultrasound so the use of MRI is necessary. More-severe lesions (second and third degree) with involvement of a larger number of myofibrils, will exhibit a hypoechoic or anechoic haema‐ toma, which can remain localised or extend along the bundles. Immediately after a trauma, the true extent of a lesion may be masked by a hyperechoichaemorrhage whereas Ultrasound done after 48–72 hours will reveal the evolution of the haematoma and the extent of the area

In cases of complete tears of the muscle belly, the retracted muscle bundles have the typical Ultrasound appearance of a bell clapper surrounded by a hypoechoichaematoma. In cases of complete tears of the muscle belly, the retracted muscle bundles have the typical Ultrasound appearance of a bell clapper surrounded by a hypoechoichaematoma. As previously emphas‐ ised, a dynamic examination is fundamental in all cases and particularly in first-degree strains, as it enables detection of the separation and dislocation of tertiary bundles and evaluation of

Muscle strains are recognisable at MRI due to changes in muscle volume and composition,

Axial scans allow for comparative examination to detect changes in muscle volume and signal intensity. Coronal or sagittal images along the muscle belly axis make it possible to define the

An important finding by Megliola et al. was that in all patients with severe contusion, the haematoma was detected with both Ultrasound and MRI, leading to a sensitivity of 100% for Ultrasound. According to Peetrons, a sonographic classification of major muscle lesions into four different types may be made on the basis of the percentage of muscle involved, but it is essential to distinguish lesions giving rise to haematomas from those causing tearing of muscle

Megliola et al. studied 29 patients with severe contusion, and Ultrasound was able not only to locate the haematoma but also to evaluate its extent in total agreement with MRI. Ultrasound

This is because the ability of Ultrasound to evaluate minor traumas is related to the presence of severe muscle oedema. In major traumas, it can accurately evaluate the extent of the lesion,

Bianchi et al. examined 17 patients with acute injury of the rectus femoris with both MRI and Ultrasound. There was concordance between the two techniques in identifying the lesions and evaluating lesion extent. The authors therefore concluded that for lesions of the rectus femoris, a very superficial muscle, Ultrasound should be considered the first-line technique. [10]

the percentage of muscle affected, the size of the scar and possible complications. [4]

has far higher sensitivity for major traumas than for minor traumas.

variations in signal intensity and pathological alterations of surrounding tissues. [9]

in the femoral quadriceps and therefore less amenable to Ultrasound.

affected. [7]

100 Muscle Injuries in Sport Medicine

the effective extent of the lesion. [8]

extent of the lesion. [6]

fibres only.

But Ultrasound (US) technologies are rapidly advancing, offering several refined transducer technologies as well as soft and hardware facilities to improve the potential clinical impact in the field of musculoskeletal (MSK) imaging.

Nowadays when using B-mode ultrasound, compound imaging and beam-steering are of help in decreasing anisotropy in tendons and ligaments, which are less well depicted due to their oblique course.

Doppler imaging has become sensitive in the detection of flow in small vessels and the use of US micro bubble contrast agents (Contrast-enhanced ultrasound –CEUS) improves detection of low-volume blood flow in smaller vessels, by increasing the signal-to-noise ratio and thereby facilitating detection of angiogenetic vessels in inflammatory conditions as for muscular lesion.

The use of US blood pool contrast agents enables molecular imaging in real-time, and thus the diagnostic potential of US is expanded, opening up a new field of US applications. Objective quantification of altered tissue (e.g., synovial proliferation) needs further development and might be improved by the use of three-dimensional imaging and software tools such as parametric evaluation.

Real-time sonoelastography (EUS) is a new development for visualization of tissue elasticity by measurement of tissue displacement in terms of stiffness changes, promising new insights into tendon disorders.

Image fusion is an exciting development that enables superimposition of CT/MRI data sets on real-time US scanning.

This technique might be helpful in guiding injections under real-time conditions even in regions less easily accessible by US as, for instance, the axial skeleton, and can additionally provide an interesting tool for teaching MSK imaging and ways to guide interventions. [12]

But, as described, MRI has very good sensitivity for the depiction of muscle lesions. Various MRI patterns of muscle injury have been described, usually including oedema-like signal alterations within torn muscle bundles. [1]

The importance of the STIR technique in detection of muscle injuries has been stressed by Greco et al., who recognized that subtle abnormalities, not easily seen on long echo T2-weighted images, are highlighted with the STIR technique as the short T1 induces suppression of fat signal and makes the effects of prolonged T1 and T2 on signal intensity additive. [13]

Imaging of muscular lesions has been greatly improved with the use of the contrast medium (Gadolinium), which grants a better definition of the muscular strain. A proof of this was provided by El-Noueam KI, Schweitzer ME, Bhatia, who described how muscle strain injury was demonstrated only in the post contrast MR scans, a pattern that we believe was not previously reported.

microscopic contracting functional units present in muscular fibres, with metabolic changes which lead to an alteration of the muscular tone, but does not reveal macroscopic damage to

All that appears with Ultrasound, despite inconsistently is greater echogenicity of the whole

MRI instead reveals slight diffuse signal hyperintensity with undefined edges due to intersti‐

Indeed several articles have shown that the small number of minor injuries observed in clinical practice is not due to their frequency but rather to ill-defined symptoms and to the fact that

Indeed several articles have shown that the small number of minor injuries observed in clinical practice is not due to their frequency but rather to ill‐defined symptoms and to the fact that Ultrasound appears to be unreliable in identifying such small

Diagnostic Imaging in Muscle Injury http://dx.doi.org/10.5772/56472 103

Actually Ultrasound sensitivity in identifying minor injuries is much lower compared to greater ones ( 70% vs 90% ), as previously highlighted. MRI instead accurately identifies even minimal muscular oedemas such as D.O.M.S. thanks to adequate sequences

D.O.M.S. of glutei maximi of a runner who had carried out long traning for the New York

**Contracture** No macroscopic anatomical injury of the fibres is shown by Ultrasound, but rather alteration of the muscular tone due to fatigue with metabolic changes, revealed by greater echogenicity

MRI shows minimal inconsistent increase in the size of the muscle due to diffused oedema and slight signal hyperintensity with ill-defined edges because of interstitial and perifascial

Example of a professional footballer

This athlete had no problem finishing the match but the following day complained of slight undefined pain in his quadriceps femoris involving a large area of the muscle. Two days after the match Ultrasound showed slight hyperechogenicity in an area with ill-defined edges

marathon a few days. Diffused oedema is shown by signal hyperintensity ( Fig.1 )

D.O.M.S. of glutei maximi of a runner who had carried out long traning for the New York

No macroscopic anatomical injury of the fibres is shown by Ultrasound, but rather alteration of the muscular tone due to fatigue with metabolic changes, revealed by greater echogenicity

MRI shows minimal inconsistent increase in the size of the muscle due to diffused oedema and slight signal hyperintensity with ill-defined edges because of interstitial and perifascialoedema

marathon a few days. Diffused oedema is shown by signal hyperintensity (Fig.1)

Actually Ultrasound sensitivity in identifying minor injuries is much lower compared to greater ones (70% vs 90%), as previously highlighted. MRI instead accurately identifies even minimal muscular oedemas such as D.O.M.S. thanks to adequate sequences which grant

muscle and a slight enlargement of the muscle due to oedema.

This proves MRI to be the gold standard in diagnosing D.O.M.S..

Ultrasound appears to be unreliable in identifying such small alterations.

Figure 1: Example of RMN with DOMS in a professional runner

**Figure 1.** Example of RMN with DOMS in a professional runner

**Case 1** 

Figure 2: US image of Contracture in a professional footballer

in the rectus femoris. ( Fig.2 )

the fibres.

**Case 1**

**Case 1**

tial and perifascialoedema.

alterations.

approximately 90% sensitivity.

which grant approximately 90% sensitivity.

Example of a professional runner

of the muscle

oedema

of the muscle

**3.2. Contracture**

Example of a professional runner

This pattern may be explained on the basis of the clinical spectrum of muscle strain injury described by O'Donoghue, as well as by considering the histological changes occurring at the miotendon junction in cases of muscle strain. O'Donoghue classified muscle strain injury as being mild, moderate, and severe. In the mild (first degree) strain, there is no appreciable tissue disruption, with neither discernible loss of strength nor any restriction of motion; the patho‐ logical changes observed at this stage are confined to low grade inflammatory process. In a moderate (second degree) strain, there is actual tissue damage that compromises the strength of the muscle tendon unit.

A severe (third degree) strain denotes complete disruption of some portion of the unit. A possible correlation is that the mild (first degree) muscle strain injury is the one detectable only on the post contrast MR scans and that the moderate and severe strain muscle injuries are readily recognized in the non contrast T2 and STIR MR sequences.However, these injuries limited the athletes' competitive participation for significant periods of time, suggesting that they were not minor injuries; so a perhaps more plausible explanation for this phenomenon is that the proliferation of MRI sites as well as the high level of medical care required by professional athletes usually mandate rapid imaging after injury. Therefore, if a longer delay in imaging had occurred, more oedema might have been present, allowing depiction of the muscle injury in the non enhanced MR study.Thus, the possibility of false negative non enhanced early MR images should be considered. A number of limitations are associated with this study but despite these limitations, they suggest the consideration of intravenous gado‐ linium in the setting of clinically suspected muscle injuries not visualized on T2 or STIR sequences. [14]

However, MRI remains the gold standard for detecting changes in muscle tissue. In some cases, MRI examinations can take the place of muscle biopsy for diagnosis. New advances in MRI include diffusion-weighted imaging, which permits assessment of fluid motion in muscles, and blood-oxygen-level-dependent imaging to evaluate tissue oxygenation. [15]

## **3. Images**

In this paragraph we have used several images in order to emphasise the characteristics of muscular lesion diagnosed over the years in professional athletes.

We do not wish to provide a new classification but rather definitions which may help better understand the type of injury and choose the best diagnostic tool.

#### **3.1. Indirect muscular injuries**

#### *3.1.1. D.O.M.S.*

D.O.M.S. stands for DELAYED ONSET of MUSCULAR SORENESS.This refers to the pain felt several hours or even days after hard training and is caused by structural damage to the microscopic contracting functional units present in muscular fibres, with metabolic changes which lead to an alteration of the muscular tone, but does not reveal macroscopic damage to the fibres.

All that appears with Ultrasound, despite inconsistently is greater echogenicity of the whole muscle and a slight enlargement of the muscle due to oedema.

MRI instead reveals slight diffuse signal hyperintensity with undefined edges due to intersti‐ tial and perifascialoedema.

This proves MRI to be the gold standard in diagnosing D.O.M.S..

Indeed several articles have shown that the small number of minor injuries observed in clinical practice is not due to their frequency but rather to ill-defined symptoms and to the fact that Ultrasound appears to be unreliable in identifying such small alterations. Indeed several articles have shown that the small number of minor injuries observed in clinical practice is not due to their frequency but rather to ill‐defined symptoms and to the fact that Ultrasound appears to be unreliable in identifying such small

Actually Ultrasound sensitivity in identifying minor injuries is much lower compared to greater ones (70% vs 90%), as previously highlighted. MRI instead accurately identifies even minimal muscular oedemas such as D.O.M.S. thanks to adequate sequences which grant approximately 90% sensitivity. alterations. Actually Ultrasound sensitivity in identifying minor injuries is much lower compared to greater ones ( 70% vs 90% ), as previously highlighted. MRI instead accurately identifies even minimal muscular oedemas such as D.O.M.S. thanks to adequate sequences which grant approximately 90% sensitivity.

#### **Case 1 Case 1**

was demonstrated only in the post contrast MR scans, a pattern that we believe was not

This pattern may be explained on the basis of the clinical spectrum of muscle strain injury described by O'Donoghue, as well as by considering the histological changes occurring at the miotendon junction in cases of muscle strain. O'Donoghue classified muscle strain injury as being mild, moderate, and severe. In the mild (first degree) strain, there is no appreciable tissue disruption, with neither discernible loss of strength nor any restriction of motion; the patho‐ logical changes observed at this stage are confined to low grade inflammatory process. In a moderate (second degree) strain, there is actual tissue damage that compromises the strength

A severe (third degree) strain denotes complete disruption of some portion of the unit. A possible correlation is that the mild (first degree) muscle strain injury is the one detectable only on the post contrast MR scans and that the moderate and severe strain muscle injuries are readily recognized in the non contrast T2 and STIR MR sequences.However, these injuries limited the athletes' competitive participation for significant periods of time, suggesting that they were not minor injuries; so a perhaps more plausible explanation for this phenomenon is that the proliferation of MRI sites as well as the high level of medical care required by professional athletes usually mandate rapid imaging after injury. Therefore, if a longer delay in imaging had occurred, more oedema might have been present, allowing depiction of the muscle injury in the non enhanced MR study.Thus, the possibility of false negative non enhanced early MR images should be considered. A number of limitations are associated with this study but despite these limitations, they suggest the consideration of intravenous gado‐ linium in the setting of clinically suspected muscle injuries not visualized on T2 or STIR

However, MRI remains the gold standard for detecting changes in muscle tissue. In some cases, MRI examinations can take the place of muscle biopsy for diagnosis. New advances in MRI include diffusion-weighted imaging, which permits assessment of fluid motion in muscles,

In this paragraph we have used several images in order to emphasise the characteristics of

We do not wish to provide a new classification but rather definitions which may help better

D.O.M.S. stands for DELAYED ONSET of MUSCULAR SORENESS.This refers to the pain felt several hours or even days after hard training and is caused by structural damage to the

and blood-oxygen-level-dependent imaging to evaluate tissue oxygenation. [15]

muscular lesion diagnosed over the years in professional athletes.

understand the type of injury and choose the best diagnostic tool.

previously reported.

102 Muscle Injuries in Sport Medicine

of the muscle tendon unit.

sequences. [14]

**3. Images**

*3.1.1. D.O.M.S.*

**3.1. Indirect muscular injuries**

Example of a professional runner Example of a professional runner

Figure 1: Example of RMN with DOMS in a professional runner D.O.M.S. of glutei maximi of a runner who had carried out long traning for the New York **Figure 1.** Example of RMN with DOMS in a professional runner

marathon a few days. Diffused oedema is shown by signal hyperintensity ( Fig.1 ) **Contracture** D.O.M.S. of glutei maximi of a runner who had carried out long traning for the New York marathon a few days. Diffused oedema is shown by signal hyperintensity (Fig.1)

#### No macroscopic anatomical injury of the fibres is shown by Ultrasound, but rather alteration **3.2. Contracture**

of the muscular tone due to fatigue with metabolic changes, revealed by greater echogenicity of the muscle MRI shows minimal inconsistent increase in the size of the muscle due to diffused oedema and slight signal hyperintensity with ill-defined edges because of interstitial and perifascial No macroscopic anatomical injury of the fibres is shown by Ultrasound, but rather alteration of the muscular tone due to fatigue with metabolic changes, revealed by greater echogenicity of the muscle

oedema **Case 1**  MRI shows minimal inconsistent increase in the size of the muscle due to diffused oedema and slight signal hyperintensity with ill-defined edges because of interstitial and perifascialoedema

Figure 2: US image of Contracture in a professional footballer

in the rectus femoris. ( Fig.2 )

Example of a professional footballer

This athlete had no problem finishing the match but the following day complained of slight undefined pain in his quadriceps femoris involving a large area of the muscle. Two days after the match Ultrasound showed slight hyperechogenicity in an area with ill-defined edges oedema

alterations.

**Case 1**

which grant approximately 90% sensitivity.

Example of a professional runner

#### **Case 1**

Example of a professional footballer **Case 1** 

Figure 2: US image of Contracture in a professional footballer

Figure 1: Example of RMN with DOMS in a professional runner

Indeed several articles have shown that the small number of minor injuries observed in clinical practice is not due to their frequency but rather to ill‐defined symptoms and to the fact that Ultrasound appears to be unreliable in identifying such small

Actually Ultrasound sensitivity in identifying minor injuries is much lower compared to greater ones ( 70% vs 90% ), as previously highlighted. MRI instead accurately identifies even minimal muscular oedemas such as D.O.M.S. thanks to adequate sequences

D.O.M.S. of glutei maximi of a runner who had carried out long traning for the New York

**Contracture** No macroscopic anatomical injury of the fibres is shown by Ultrasound, but rather alteration

MRI shows minimal inconsistent increase in the size of the muscle due to diffused oedema and slight signal hyperintensity with ill-defined edges because of interstitial and perifascial

marathon a few days. Diffused oedema is shown by signal hyperintensity ( Fig.1 )

**Case 1**

**Case 2**

Example of a professional footballer

Example of a professional footballer

with ill-defined edges in the Semitendinosus. (Fig.3)

Figure 3: US image of Elongation in a professional footballer

Figure 4: US image of Elongation in a professional footballer

Figure 5: Example of Elongation in an RMN of a professional footballer

in an area with ill-defined edges in the Semitendinosus. ( Fig.3 )

Example of a professional footballer

**Figure 4.** US image of Elongation in a professional footballer

**Figure 5.** Example of Elongation in an RMN of a professional footballer

This athlete had no problem finishing the match but the following day complained of unde‐ fined pain and slight functional impotence in his Hamstrings involving a large area. Two days after the match Ultrasound showed slight hypoechogenicity, due to slight oedema, in an area

This athlete had no problem finishing the match but the following day complained of undefined pain and slight functional impotence in his Hamstrings involving a large area. Two days after the match Ultrasound showed slight hypoechogenicity, due to slight oedema,

Diagnostic Imaging in Muscle Injury http://dx.doi.org/10.5772/56472 105

**Case 2** 

This athlete had no problem finishing the match but the following day complained of slight **Figure 2.** US image of Contracture in a professional footballer

undefined pain in his quadriceps femoris involving a large area of the muscle. Two days after the match Ultrasound showed slight hyperechogenicity in an area with ill-defined edges in the rectus femoris. ( Fig.2 ) This athlete had no problem finishing the match but the following day complained of slight undefined pain in his quadriceps femoris involving a large area of the muscle. Two days after the match Ultrasound showed slight hyperechogenicity in an area with ill-defined edges in the rectus femoris. (Fig.2)

#### **3.3. Strain (Elongation)**

No macroscopic anatomical injury of the fibres is shown by Ultrasound, rather microscopic alteration which in the acute stage are revealed by slight hyperechogenicity due to oedema and affected muscle and by a hypoechoic blurred area in the sub acutestage.MRI reveals slight focal signal hyperintesity

in an area with ill-defined edges in the Semitendinosus. ( Fig.3 )

Example of a professional footballer

undefined pain and slight functional impotence in his Hamstrings involving a large area. Two days after the match Ultrasound showed slight hypoechogenicity, due to slight oedema,

**Case 2** 

Figure 3: US image of Elongation in a professional footballer

Figure 4: US image of Elongation in a professional footballer

Figure 5: Example of Elongation in an RMN of a professional footballer

This athlete had no problem finishing the match but the following day complained of **Figure 3.** US image of Elongation in a professional footballer

### **Case 1**

**Case 1**

Example of a professional footballer

**Case 1** 

Figure 2: US image of Contracture in a professional footballer

This athlete had no problem finishing the match but the following day complained of slight undefined pain in his quadriceps femoris involving a large area of the muscle. Two days after the match Ultrasound showed slight hyperechogenicity in an area with ill-defined edges in

No macroscopic anatomical injury of the fibres is shown by Ultrasound, rather microscopic alteration which in the acute stage are revealed by slight hyperechogenicity due to oedema and affected muscle and by a hypoechoic blurred area in the sub acutestage.MRI reveals slight

Figure 3: US image of Elongation in a professional footballer

**Figure 3.** US image of Elongation in a professional footballer

Figure 4: US image of Elongation in a professional footballer

Figure 5: Example of Elongation in an RMN of a professional footballer

in an area with ill-defined edges in the Semitendinosus. ( Fig.3 )

Example of a professional footballer

This athlete had no problem finishing the match but the following day complained of undefined pain and slight functional impotence in his Hamstrings involving a large area. Two days after the match Ultrasound showed slight hypoechogenicity, due to slight oedema,

**Case 2** 

in the rectus femoris. ( Fig.2 )

**Figure 2.** US image of Contracture in a professional footballer

of the muscle

oedema

104 Muscle Injuries in Sport Medicine

the rectus femoris. (Fig.2)

**3.3. Strain (Elongation)**

focal signal hyperintesity

alterations.

**Case 1**

which grant approximately 90% sensitivity.

Figure 1: Example of RMN with DOMS in a professional runner

Example of a professional runner

Indeed several articles have shown that the small number of minor injuries observed in clinical practice is not due to their frequency but rather to ill‐defined symptoms and to the fact that Ultrasound appears to be unreliable in identifying such small

Actually Ultrasound sensitivity in identifying minor injuries is much lower compared to greater ones ( 70% vs 90% ), as previously highlighted. MRI instead accurately identifies even minimal muscular oedemas such as D.O.M.S. thanks to adequate sequences

D.O.M.S. of glutei maximi of a runner who had carried out long traning for the New York

**Contracture** No macroscopic anatomical injury of the fibres is shown by Ultrasound, but rather alteration of the muscular tone due to fatigue with metabolic changes, revealed by greater echogenicity

MRI shows minimal inconsistent increase in the size of the muscle due to diffused oedema and slight signal hyperintensity with ill-defined edges because of interstitial and perifascial

Example of a professional footballer

This athlete had no problem finishing the match but the following day complained of slight undefined pain in his quadriceps femoris involving a large area of the muscle. Two days after the match Ultrasound showed slight hyperechogenicity in an area with ill-defined edges

marathon a few days. Diffused oedema is shown by signal hyperintensity ( Fig.1 )

Example of a professional footballer

This athlete had no problem finishing the match but the following day complained of unde‐ fined pain and slight functional impotence in his Hamstrings involving a large area. Two days after the match Ultrasound showed slight hypoechogenicity, due to slight oedema, in an area with ill-defined edges in the Semitendinosus. (Fig.3)

This athlete had no problem finishing the match but the following day complained of

#### **Case 2**

Example of a professional footballer Figure 3: US image of Elongation in a professional footballer

**Figure 4.** US image of Elongation in a professional footballer 

Figure 4: US image of Elongation in a professional footballer

Figure 5: Example of Elongation in an RMN of a professional footballer

**Figure 5.** Example of Elongation in an RMN of a professional footballer

The ultrasound of this athlete was negative (Fig.4), yet the MRI carried out because of the symptoms highlighted an oedema of VastusIntermedius, shown by a minimal area of hyper‐ intensity due to minimal myofascial elongation (Fig.5)

#### **3.4. First degree injuries**

First degree injuries are characterized by the tear of fibres in the muscle (<5%) with oedema and small haemorrhage because of the vascularisation of connective tissue.

In the acute stage the Ultrasound highlighted a slightly hypoechoic area whilst in the sub-acute phase a dishomogeneoushypoechoic focal area was revealed with initial modification showing a small anaechoic inter or intramuscular area (usually<1cm) depending of the size of the muscle.

MRI instead showed an increase in muscle size due to oedema with slight dishomogeneous signal hyperintensity due to interstitial and perifascialoedematogheter with small focal signal hyperintensity due to small haemorrhage

#### **Case 1**

Example of a professional rugby player

Figure 6: US image of First degree lesion in a professional rugby player **Figure 6.** US image of First degree lesion in a professional rugby player

**Case 2**  The player came for a check two days after a match when after a sharp movement in a tackle he started felling pain in a precise point of his thigh.

Example of a professional rugby player Ultrasound highlighted an anaechoic area due to haemorrage as from first degree injury of the Hamstrings (Fig.6)

14

14

Diagnostic Imaging in Muscle Injury http://dx.doi.org/10.5772/56472 107

Figure 6: US image of First degree lesion in a professional rugby player

**Figure 7.** US images of First degree lesion in a professional rugby player

the pelvis followed by sharp pain in the lower abdomen.

Figure 7. US images of First degree lesion in a professional rugby player

Abdominal external obliquemuscle. (Fig.7)

oblique muscle.( Fig.7 )

Example of a professional footballer

Example of a professional rugby player

**Case 2**

**Case 3**

**Case 2** 

Example of a professional rugby player

The player came for a check three days after a match when after a sharp movement in a tackle he complained of hyperextention of the pelvis followed by sharp pain in the lower abdomen.

The player came for a check three days after a match when after a sharp movement in a tackle he complained of hyperextention of

Ultrasound highlighted an anaechoic area due to haemorrage as from first degree injury of the Abdominal external

Ultrasound highlighted an anaechoic area due to haemorrage as from first degree injury of the Hamstrings ( Fig.6 )

Ultrasound highlighted an anaechoic area due to haemorrage as from first degree injury of the

Figure 8: US images of First degree lesion in a professional footballer

**Figure 8.** US images of First degree lesion in a professional footballer

Figure 9: RMN images of First degree lesion in a professional footballer

The ultrasound showed an anaechoic area due to haemorrhage.( Fig.8 )

playing a match but felt no further symptoms.

complained of the same pain.

A professional footballer felt a slight pain in the distal section of the adductor muscle while

He therefore started a rehabilitation program but when he started more intense activity he

#### **Case 2**

Example of a professional rugby player

**Case 2** 

Example of a professional rugby player

Figure 6: US image of First degree lesion in a professional rugby player

**Figure 7.** US images of First degree lesion in a professional rugby player Figure 7. US images of First degree lesion in a professional rugby player The player came for a check three days after a match when after a sharp movement in a tackle he complained of hyperextention of

Example of a professional footballer

**Case 2**

The ultrasound of this athlete was negative (Fig.4), yet the MRI carried out because of the symptoms highlighted an oedema of VastusIntermedius, shown by a minimal area of hyper‐

First degree injuries are characterized by the tear of fibres in the muscle (<5%) with oedema

In the acute stage the Ultrasound highlighted a slightly hypoechoic area whilst in the sub-acute phase a dishomogeneoushypoechoic focal area was revealed with initial modification showing a small anaechoic inter or intramuscular area (usually<1cm) depending of the size of the

MRI instead showed an increase in muscle size due to oedema with slight dishomogeneous signal hyperintensity due to interstitial and perifascialoedematogheter with small focal signal

Figure 6: US image of First degree lesion in a professional rugby player

The player came for a check two days after a match when after a sharp movement in a tackle

Ultrasound highlighted an anaechoic area due to haemorrage as from first degree injury of the

**Case 2** 

Example of a professional rugby player

and small haemorrhage because of the vascularisation of connective tissue.

intensity due to minimal myofascial elongation (Fig.5)

hyperintensity due to small haemorrhage

Example of a professional rugby player

**Figure 6.** US image of First degree lesion in a professional rugby player

he started felling pain in a precise point of his thigh.

Example of a professional rugby player

Hamstrings (Fig.6)

**Case 2**

**3.4. First degree injuries**

106 Muscle Injuries in Sport Medicine

muscle.

**Case 1**

The player came for a check three days after a match when after a sharp movement in a tackle he complained of hyperextention of the pelvis followed by sharp pain in the lower abdomen. the pelvis followed by sharp pain in the lower abdomen. Ultrasound highlighted an anaechoic area due to haemorrage as from first degree injury of the Abdominal external

Ultrasound highlighted an anaechoic area due to haemorrage as from first degree injury of the Abdominal external obliquemuscle. (Fig.7) oblique muscle.( Fig.7 ) **Case 3**

Figure 8: US images of First degree lesion in a professional footballer **Figure 8.** US images of First degree lesion in a professional footballer

Figure 9: RMN images of First degree lesion in a professional footballer

The ultrasound showed an anaechoic area due to haemorrhage.( Fig.8 )

playing a match but felt no further symptoms.

complained of the same pain.

A professional footballer felt a slight pain in the distal section of the adductor muscle while

He therefore started a rehabilitation program but when he started more intense activity he

14

**Case 3**

**Case 2**

Example of a professional rugby player

oblique muscle.( Fig.7 )

Example of a professional footballer

Figure 7. US images of First degree lesion in a professional rugby player

the pelvis followed by sharp pain in the lower abdomen.

### **Case 3**

Example of a professional footballer (Fig.8-Fig.9) Figure 8: US images of First degree lesion in a professional footballer

Ultrasound highlighted an anaechoic area due to haemorrage as from first degree injury of the Hamstrings ( Fig.6 )

The player came for a check three days after a match when after a sharp movement in a tackle he complained of hyperextention of

Ultrasound highlighted an anaechoic area due to haemorrage as from first degree injury of the Abdominal external

US Figure 10: US images of First degree lesion in a professional swimmer

US Figure 10: US images of First degree lesion in a professional swimmer

US Figure 11: RMN images of First degree lesion in a professional swimmer

US Figure 11: RMN images of First degree lesion in a professional swimmer

after diving but was able to compete.

after diving but was able to compete.

**Figure 11.** RMN images of First degree lesion in a professional swimmer

Fig.10 )

Fig.10 )

10)

**Case 5**

diving but was able to compete.

Example of a professional runner

This is the case of a professional swimmer who complained of left groin pain for two days

Diagnostic Imaging in Muscle Injury http://dx.doi.org/10.5772/56472 109

Ultrasound highlighted a small thin hypoechoic area due to oedema along the ileo-psoas.(

This is the case of a professional swimmer who complained of left groin pain for two days

Ultrasound highlighted a small thin hypoechoic area due to oedema along the ileo-psoas.(

This showed changes in muscle volume and structure and signal hyperintensity when using axial imaging in comparative assessment for volume and variations as for oedema and

This showed changes in muscle volume and structure and signal hyperintensity when using axial imaging in comparative assessment for volume and variations as for oedema and

> **Case 5** Example of a professional runner

**Case 5** Example of a professional runner

Due to the mismatch between the symptoms and diagnostics an MRI was carried out

Due to the mismatch between the symptoms and diagnostics an MRI was carried out

haemorrhage from ileo-psoas injury linked to tendon partial tear.( Fig.11 )

haemorrhage from ileo-psoas injury linked to tendon partial tear.( Fig.11 )

This showed changes in muscle volume and structure and signal hyperintensity when using axial imaging in comparative assessment for volume and variations as for oedema and

Due to the mismatch between the symptoms and diagnostics an MRI was carried out

haemorrhage from ileo-psoas injury linked to tendon partial tear. (Fig.11)

This is the case of a professional swimmer who complained of left groin pain for two days after

Ultrasound highlighted a small thin hypoechoic area due to oedema along the ileo-psoas. (Fig.

Figure 12: RMN images of First degree lesion in a professional runner Example of a runner complaining of a sharp pain in the calf

Figure 12: RMN images of First degree lesion in a professional runner Example of a runner complaining of a sharp pain in the calf **Figure 12.** RMN images of First degree lesion in a professional runner

mismatch between the symptoms and diagnostics an MRI was carried out.

haemorrhage from first degree injury of the flexor hallucislongus muscle. (Fig.12)

The Ultrasound showed a small thin oedema along the flexor hallucislongusmuscle.Due to the

This showed changes in muscle volume and structure and signal hyperintensity when using axial imaging in comparative assessment for volume and variations as for oedema and

Example of a runner complaining of a sharp pain in the calf

Figure 9: RMN images of First degree lesion in a professional footballer **Figure 9.** RMN images of First degree lesion in a professional footballer

A professional footballer felt a slight pain in the distal section of the adductor muscle while playing a match but felt no further symptoms. He therefore started a rehabilitation program but when he started more intense activity he A professional footballer felt a slight pain in the distal section of the adductor muscle while playing a match but felt no further symptoms.

complained of the same pain. He therefore started a rehabilitation program but when he started more intense activity he complained of the same pain.

The ultrasound showed an anaechoic area due to haemorrhage.( Fig.8 ) The ultrasound showed an anaechoic area due to haemorrhage. (Fig.8)

The MRI was therefore essential to assess the real extension of the injury and highlight mio tendon retraction. (Fig.9)

The analysis was carried out the following day and showed changes in muscle volume and structure and signal hyperintensity when using axial imaging in comparative assessment for volume and variations, whilst coronal and sagital images defined the extension of the injury, i.e. a first degree myofascial injury of longus adductor.

#### **Case 4**

Example of a professional swimmer

US Figure 11: RMN images of First degree lesion in a professional swimmer

This is the case of a professional swimmer who complained of left groin pain for two days

Ultrasound highlighted a small thin hypoechoic area due to oedema along the ileo-psoas.(

This showed changes in muscle volume and structure and signal hyperintensity when using axial imaging in comparative assessment for volume and variations as for oedema and

> **Case 5** Example of a professional runner

Due to the mismatch between the symptoms and diagnostics an MRI was carried out

haemorrhage from ileo-psoas injury linked to tendon partial tear.( Fig.11 )

Figure 12: RMN images of First degree lesion in a professional runner Example of a runner complaining of a sharp pain in the calf

US Figure 10: US images of First degree lesion in a professional swimmer **Figure 10.** US images of First degree lesion in a professional swimmer

after diving but was able to compete.

Fig.10 )

US Figure 10: US images of First degree lesion in a professional swimmer

US Figure 11: RMN images of First degree lesion in a professional swimmer This is the case of a professional swimmer who complained of left groin pain for two days **Figure 11.** RMN images of First degree lesion in a professional swimmer

after diving but was able to compete. Ultrasound highlighted a small thin hypoechoic area due to oedema along the ileo-psoas.( This is the case of a professional swimmer who complained of left groin pain for two days after diving but was able to compete. US Figure 11: RMN images of First degree lesion in a professional swimmer This is the case of a professional swimmer who complained of left groin pain for two days after diving but was able to compete.

Fig.10 ) Due to the mismatch between the symptoms and diagnostics an MRI was carried out This showed changes in muscle volume and structure and signal hyperintensity when using Ultrasound highlighted a small thin hypoechoic area due to oedema along the ileo-psoas. (Fig. 10) Ultrasound highlighted a small thin hypoechoic area due to oedema along the ileo-psoas.( Fig.10 )

axial imaging in comparative assessment for volume and variations as for oedema and Due to the mismatch between the symptoms and diagnostics an MRI was carried out Due to the mismatch between the symptoms and diagnostics an MRI was carried out This showed changes in muscle volume and structure and signal hyperintensity when using

haemorrhage from ileo-psoas injury linked to tendon partial tear.( Fig.11 ) This showed changes in muscle volume and structure and signal hyperintensity when using axial imaging in comparative assessment for volume and variations as for oedema and haemorrhage from ileo-psoas injury linked to tendon partial tear. (Fig.11) axial imaging in comparative assessment for volume and variations as for oedema and haemorrhage from ileo-psoas injury linked to tendon partial tear.( Fig.11 )

> **Case 5** Example of a professional runner

**Case 5**

#### **Case 5**

**Case 3**

**Case 2**

**Case 3**

108 Muscle Injuries in Sport Medicine

Example of a professional rugby player

oblique muscle.( Fig.7 )

Example of a professional footballer

Figure 7. US images of First degree lesion in a professional rugby player

the pelvis followed by sharp pain in the lower abdomen.

Example of a professional footballer (Fig.8-Fig.9)

Figure 8: US images of First degree lesion in a professional footballer

Figure 9: RMN images of First degree lesion in a professional footballer

The ultrasound showed an anaechoic area due to haemorrhage.( Fig.8 )

A professional footballer felt a slight pain in the distal section of the adductor muscle while

He therefore started a rehabilitation program but when he started more intense activity he

The MRI was therefore essential to assess the real extension of the injury and highlight mio

The analysis was carried out the following day and showed changes in muscle volume and structure and signal hyperintensity when using axial imaging in comparative assessment for volume and variations, whilst coronal and sagital images defined the extension of the injury,

US Figure 10: US images of First degree lesion in a professional swimmer

US Figure 11: RMN images of First degree lesion in a professional swimmer

after diving but was able to compete.

Fig.10 )

This is the case of a professional swimmer who complained of left groin pain for two days

Ultrasound highlighted a small thin hypoechoic area due to oedema along the ileo-psoas.(

This showed changes in muscle volume and structure and signal hyperintensity when using axial imaging in comparative assessment for volume and variations as for oedema and

> **Case 5** Example of a professional runner

Due to the mismatch between the symptoms and diagnostics an MRI was carried out

haemorrhage from ileo-psoas injury linked to tendon partial tear.( Fig.11 )

Figure 12: RMN images of First degree lesion in a professional runner Example of a runner complaining of a sharp pain in the calf

playing a match but felt no further symptoms.

The ultrasound showed an anaechoic area due to haemorrhage. (Fig.8)

**Figure 9.** RMN images of First degree lesion in a professional footballer

i.e. a first degree myofascial injury of longus adductor.

**Figure 10.** US images of First degree lesion in a professional swimmer

complained of the same pain.

complained of the same pain.

tendon retraction. (Fig.9)

Example of a professional swimmer

**Case 4**

playing a match but felt no further symptoms.

A professional footballer felt a slight pain in the distal section of the adductor muscle while

He therefore started a rehabilitation program but when he started more intense activity he

Ultrasound highlighted an anaechoic area due to haemorrage as from first degree injury of the Hamstrings ( Fig.6 )

The player came for a check three days after a match when after a sharp movement in a tackle he complained of hyperextention of

Ultrasound highlighted an anaechoic area due to haemorrage as from first degree injury of the Abdominal external

Example of a professional runner

Example of a runner complaining of a sharp pain in the calf Figure 12: RMN images of First degree lesion in a professional runner Example of a runner complaining of a sharp pain in the calf **Figure 12.** RMN images of First degree lesion in a professional runner

Example of a runner complaining of a sharp pain in the calf

The Ultrasound showed a small thin oedema along the flexor hallucislongusmuscle.Due to the mismatch between the symptoms and diagnostics an MRI was carried out.

This showed changes in muscle volume and structure and signal hyperintensity when using axial imaging in comparative assessment for volume and variations as for oedema and haemorrhage from first degree injury of the flexor hallucislongus muscle. (Fig.12)

### **Case 6**

Example of a professional footballer

Figure 13: US image of First degree lesion in a professional footballer **Figure 13.** US image of First degree lesion in a professional footballer

This is the case of a goalkeeper who felt a slight pain in his shoulder during a save.The Ultrasound showed a small thin hypoechoic area due to oedema along the Trapezius muscle as for first degree injury. (Fig.13)

#### **3.5. Second degree injury**

Second degree injuries are characterized by the tear of a higher number of fibres in the muscle (<70%, < 2/3 of the muscle) with greater oedema and haemorrhage due to the wider involve‐ ment of the connective tissue.

Because of the wide range they are divided into initial and advanced second degree injuries.

<sup>F</sup> Figure 14: US image of Second degree lesion in a professional footballer It is sometimes difficult to define the injury degree precisely as the muscles affected can be very long, so injuries which are first degree should be classified as second degree and this leads to a simple description without a real classification.

In the acute stage the Ultrasound highlighted an iso-hyperechoic area whilst in the sub-acute phase a large, clearly dishomogeneousanaechoic area was revealed with structural change showing a large anaechoic inter or intramuscular area (usually<3cm) depending of the size of the muscle.

MRI instead showed an increase in muscle size due to oedema with dishomogeneous signal hyperintensity due to interstitial and perifascialoedema together with a mass of fluid with focal signal hyperintensity due to haemorrhage

Example of a volleyball player who, following the movement of the arm in

spiking during a match, felt a sharp pain in the abdomen

18

18

18

<sup>F</sup>

Diagnostic Imaging in Muscle Injury http://dx.doi.org/10.5772/56472 111

<sup>F</sup>

Figure 13: US image of First degree lesion in a professional footballer

Figure 13: US image of First degree lesion in a professional footballer

Figure 14: US image of Second degree lesion in a professional footballer

Major League footballer who on the previous day felt a very sharp pain in a sprint and left the

Ultrasound highlighted a clearly dishomogeneous area with marked structural change showing a large intramuscular anaechoic area (<3cm), as from second degree injury of the

Figure 15: US image of First degree lesion in a professional volleyball player

Figure 15: US image of First degree lesion in a professional volleyball player

spiking during a match, felt a sharp pain in the abdomen

**Figure 15.** US image of First degree lesion in a professional volleyball player

Example of a volleyball player who, following the movement of the arm in

Example of a volleyball player who, following the movement of the arm in spiking during a

Ultrasound highlighted a clearly dishomogeneous area with marked structural change showing a large intramuscular anaechoic area (>3cm), as from second degree injury of the

spiking during a match, felt a sharp pain in the abdomen

**Figure 14.** US image of Second degree lesion in a professional footballer

match

**Case 2**

Biceps Femoris. (Fig.14)

Example of a professional volleyball player

match, felt a sharp pain in the abdomen

Rectus Abdominis. (Fig.15)

Example of a volleyball player who, following the movement of the arm in

Figure 14: US image of Second degree lesion in a professional footballer

#### Figure 15: US image of First degree lesion in a professional volleyball player **Case 1**

Example of a professional footballer

<sup>F</sup>

Figure 13: US image of First degree lesion in a professional footballer

Figure 14: US image of Second degree lesion in a professional footballer **Figure 14.** US image of Second degree lesion in a professional footballer

Major League footballer who on the previous day felt a very sharp pain in a sprint and left the match

Ultrasound highlighted a clearly dishomogeneous area with marked structural change showing a large intramuscular anaechoic area (<3cm), as from second degree injury of the Biceps Femoris. (Fig.14)

Figure 14: US image of Second degree lesion in a professional footballer

#### **Case 2**

18

<sup>F</sup>

**Case 6**

110 Muscle Injuries in Sport Medicine

Example of a professional footballer

Figure 13: US image of First degree lesion in a professional footballer

**Figure 13.** US image of First degree lesion in a professional footballer

to a simple description without a real classification.

focal signal hyperintensity due to haemorrhage

Example of a professional footballer

as for first degree injury. (Fig.13)

**3.5. Second degree injury**

ment of the connective tissue.

the muscle.

**Case 1**

Figure 14: US image of Second degree lesion in a professional footballer

In the acute stage the Ultrasound highlighted an iso-hyperechoic area whilst in the sub-acute phase a large, clearly dishomogeneousanaechoic area was revealed with structural change showing a large anaechoic inter or intramuscular area (usually<3cm) depending of the size of

MRI instead showed an increase in muscle size due to oedema with dishomogeneous signal hyperintensity due to interstitial and perifascialoedema together with a mass of fluid with

This is the case of a goalkeeper who felt a slight pain in his shoulder during a save.The Ultrasound showed a small thin hypoechoic area due to oedema along the Trapezius muscle

Second degree injuries are characterized by the tear of a higher number of fibres in the muscle (<70%, < 2/3 of the muscle) with greater oedema and haemorrhage due to the wider involve‐

Because of the wide range they are divided into initial and advanced second degree injuries.

It is sometimes difficult to define the injury degree precisely as the muscles affected can be very long, so injuries which are first degree should be classified as second degree and this leads

Figure 15: US image of First degree lesion in a professional volleyball player

spiking during a match, felt a sharp pain in the abdomen

Example of a volleyball player who, following the movement of the arm in

Figure 15: US image of First degree lesion in a professional volleyball player Example of a professional volleyball player

**Figure 15.** US image of First degree lesion in a professional volleyball player

Example of a volleyball player who, following the movement of the arm in spiking during a match, felt a sharp pain in the abdomen Example of a volleyball player who, following the movement of the arm in spiking during a match, felt a sharp pain in the abdomen

Figure 15: US image of First degree lesion in a professional volleyball player

18 Ultrasound highlighted a clearly dishomogeneous area with marked structural change showing a large intramuscular anaechoic area (>3cm), as from second degree injury of the Rectus Abdominis. (Fig.15)

### **Case 3**

Example of a professional footballer

**Figure 16.** US images of Second degree lesion in a professional footballer

**Figure 17.** RMN images of Second degree lesion in a professional footballer

Figure 17: RMN images of Second degree lesion in a professional footballer Example of a footballer who during pre-match warm-up felt a sharp pain in the calf which did not prevent him from playing up to the second half

Ultrasound highlighted a clearly dishomogeneous area with marked structural change showing a large intramuscular anaechoic area (>5 cm) with large haemorrage, as from second degree injury. (Fig.16)

MRI instead showed an increase in muscle size due to oedemawith dishomogeneous signal hyperintensity due to interstitial and perifascialoedema together with a mass of fluid with focal signal hyperintensity due to haemorrhage. (Fig.17)

Figure 18: US images of Second degree lesion in a professional footballer

Example of a goalkeeper who during a kick felt a very sharp pain in the

MRI instead showed an increase in muscle size due to oedema with

Ultrasound highlighted a clearly dishomogeneous area with marked structural change showing a large intramuscular anaechoic area (>5 cm) with large

dishomogeneous signal hyperintensity due to interstitial and perifascial oedema

20

20

Diagnostic Imaging in Muscle Injury http://dx.doi.org/10.5772/56472 113

Figure 17: RMN images of Second degree lesion in a professional footballer

Figure 18: US images of Second degree lesion in a professional footballer

Example of a goalkeeper who during a kick felt a very sharp pain in the

showing a large intramuscular anaechoic area (>5 cm) with large haemorrhage.

Example of a goalkeeper who during a kick felt a very sharp pain in the quadriceps

**Figure 18.** US images of Second degree lesion in a professional footballer

Example of a goalkeeper who during a kick felt a very sharp pain in the quadriceps

**Figure 19.** US images of Second degree lesion in a professional footballer

These images are typical of a second degree injury of Soleus mucle

focal signal hyperintensity due to haemorrhage.

These images are typical of a second degree injury of Rectus Femoris

Figure 18.US images of Second degree lesion in a professional footballer

Example of a professional footballer

MRI instead showed an increase in muscle size due to oedema with

These images are typical of a second degree injury of RectusFemoris

perifascial oedema together with a mass of fluid with focal signal hyperintensity due to haemorrhage.

Ultrasound highlighted a clearly dishomogeneous area with marked structural change showing a large intramuscular anaechoic area (>5 cm) with large

Ultrasound highlighted a clearly dishomogeneous area with marked structural change

MRI instead showed an increase in muscle size due to oedema with dishomogeneous signal hyperintensity due to interstitial and perifascialoedema together with a mass of fluid with

Ultrasound highlighted a clearly dishomogeneous area with marked structural change showing a large intramuscular anaechoic

MRI instead showed an increase in muscle size due to oedema with dishomogeneous signal hyperintensity due to interstitial and

<sup>F</sup>

Figure 19: US images of Second degree lesion in a professional footballer

Figure 20: RMN images of Second degree lesion in a professional footballer

Major League footballer who felt a very sharp pain in a sprint on 29 September.

dishomogeneous signal hyperintensity due to interstitial and perifascial oedema

quadriceps

Example of a professional footballer

haemorrhage.

Example of a professional footballer

area (>5 cm) with large haemorrhage.

**Case 5**

**Case 5**

**Case 4** 

These images are typical of a second degree injury of Soleus mucle

#### **Case 4**

Example of a professional footballer

quadriceps

haemorrhage.

Figure 17: RMN images of Second degree lesion in a professional footballer

**Figure 18.** US images of Second degree lesion in a professional footballer

Example of a goalkeeper who during a kick felt a very sharp pain in the Example of a goalkeeper who during a kick felt a very sharp pain in the quadriceps

quadriceps Ultrasound highlighted a clearly dishomogeneous area with marked structural change showing a large intramuscular anaechoic area (>5 cm) with large haemorrhage. Figure 18.US images of Second degree lesion in a professional footballer Example of a goalkeeper who during a kick felt a very sharp pain in the quadriceps

Figure 18: US images of Second degree lesion in a professional footballer

Ultrasound highlighted a clearly dishomogeneous area with marked structural change showing a large intramuscular anaechoic area (>5 cm) with large haemorrhage. MRI instead showed an increase in muscle size due to oedema with dishomogeneous signal hyperintensity due to interstitial and perifascialoedema together with a mass of fluid with focal signal hyperintensity due to haemorrhage. Ultrasound highlighted a clearly dishomogeneous area with marked structural change showing a large intramuscular anaechoic area (>5 cm) with large haemorrhage.

MRI instead showed an increase in muscle size due to oedema with These images are typical of a second degree injury of RectusFemoris MRI instead showed an increase in muscle size due to oedema with dishomogeneous signal hyperintensity due to interstitial and perifascial oedema together with a mass of fluid with focal signal hyperintensity due to haemorrhage.

dishomogeneous signal hyperintensity due to interstitial and perifascial oedema **Case 5** These images are typical of a second degree injury of Rectus Femoris

**Case 4** 

20

**Case 3**

112 Muscle Injuries in Sport Medicine

Example of a professional footballer

**Figure 16.** US images of Second degree lesion in a professional footballer

**Figure 17.** RMN images of Second degree lesion in a professional footballer

not prevent him from playing up to the second half

focal signal hyperintensity due to haemorrhage. (Fig.17)

These images are typical of a second degree injury of Soleus mucle

Figure 17: RMN images of Second degree lesion in a professional footballer

Example of a footballer who during pre-match warm-up felt a sharp pain in the calf which did

Ultrasound highlighted a clearly dishomogeneous area with marked structural change showing a large intramuscular anaechoic area (>5 cm) with large haemorrage, as from second

MRI instead showed an increase in muscle size due to oedemawith dishomogeneous signal hyperintensity due to interstitial and perifascialoedema together with a mass of fluid with

Figure 18: US images of Second degree lesion in a professional footballer

Example of a goalkeeper who during a kick felt a very sharp pain in the

MRI instead showed an increase in muscle size due to oedema with

Ultrasound highlighted a clearly dishomogeneous area with marked structural change showing a large intramuscular anaechoic area (>5 cm) with large

dishomogeneous signal hyperintensity due to interstitial and perifascial oedema

quadriceps

Example of a professional footballer

degree injury. (Fig.16)

**Case 4**

haemorrhage.

Example of a professional footballer **Case 5**

Example of a professional footballer

Figure 19: US images of Second degree lesion in a professional footballer

Figure 20: RMN images of Second degree lesion in a professional footballer

Major League footballer who felt a very sharp pain in a sprint on 29 September.

**Figure 19.** US images of Second degree lesion in a professional footballer

These images are typical of a second degree injury of Soleus mucle

Figure 18.US images of Second degree lesion in a professional footballer

These images are typical of a second degree injury of Rectus Femoris

Example of a goalkeeper who during a kick felt a very sharp pain in the quadriceps

perifascial oedema together with a mass of fluid with focal signal hyperintensity due to haemorrhage.

**Case 4** 

**Case 5**

Example of a professional footballer

area (>5 cm) with large haemorrhage.

Example of a professional footballer

<sup>F</sup>

Diagnostic Imaging in Muscle Injury http://dx.doi.org/10.5772/56472 115

<sup>F</sup>

<sup>F</sup>

<sup>F</sup>

<sup>F</sup>

Figure 21: US image of Second degree lesion in a professional footballer

Figure 21: US image of Second degree lesion in a professional footballer

Figure 22: RMN images of Second degree lesion in a professional footballer

Figure 22: RMN images of Second degree lesion in a professional footballer

Figure 23: RMN images of Second degree lesion in a professional footballer Professional footballer who felt a harp pain in the groin after a match but was able despite

Figure 23: RMN images of Second degree lesion in a professional footballer Professional footballer who felt a harp pain in the groin after a match but was able despite

the pain to carry out differentia **Figure 23.** RMN images of Second degree lesion in a professional footballer ted training for four-five days.

the pain to carry out differentiated training for four-five days.

**Figure 22.** RMN images of Second degree lesion in a professional footballer

Ultrasound highlighted a clearly dishomogeneous area with marked structural change showing a large intramuscular anaechoic

MRI instead showed an increase in muscle size due to oedema with dishomogeneous signal hyperintensity due to interstitial and

**Figure 20.** RMN images of Second degree lesion in a professional footballer

Major League footballer who felt a very sharp pain in a sprint on 29 September. Major League footballer who felt a very sharp pain in a sprint on 29 September.

The first Ultrasound on 1October highlighted a large anaechoic area as from second degree miotendon injury of the Semimembranosus. (Fig.19)

Figure 20: RMN images of Second degree lesion in a professional footballer

MRI on 15 October highlighted a wide area with signal hyperintensity confirming the mio‐ tendon injury and intratendon tear too. (Fig.20)

Figure 21: US image of Second degree lesion in a professional footballer **Figure 21.** US image of Second degree lesion in a professional footballer

Follow-up analyses, i.e. Ultrasound on 19 October (Fig.21), MRI on 24 October and MRI on 2 November show the development of the pathology up to the disappearance of the modified signal in MRI as from recovery. (Fig.22)

Figure 22: RMN images of Second degree lesion in a professional footballer

Figure 23: RMN images of Second degree lesion in a professional footballer Professional footballer who felt a harp pain in the groin after a match but was able despite

the pain to carry out differentiated training for four-five days.

<sup>F</sup>

<sup>F</sup>

#### **Case 6**

Example of a professional footballer

<sup>F</sup>

<sup>F</sup>

**Figure 22.** RMN images of Second degree lesion in a professional footballer

These images are typical of a second degree injury of Soleus mucle

Figure 18.US images of Second degree lesion in a professional footballer

These images are typical of a second degree injury of Rectus Femoris

Example of a goalkeeper who during a kick felt a very sharp pain in the quadriceps

perifascial oedema together with a mass of fluid with focal signal hyperintensity due to haemorrhage.

Ultrasound highlighted a clearly dishomogeneous area with marked structural change showing a large intramuscular anaechoic

MRI instead showed an increase in muscle size due to oedema with dishomogeneous signal hyperintensity due to interstitial and

<sup>F</sup>

Figure 19: US images of Second degree lesion in a professional footballer

Figure 20: RMN images of Second degree lesion in a professional footballer

The first Ultrasound on 1October highlighted a large anaechoic area as from second degree

MRI on 15 October highlighted a wide area with signal hyperintensity confirming the mio‐

Figure 21: US image of Second degree lesion in a professional footballer

Follow-up analyses, i.e. Ultrasound on 19 October (Fig.21), MRI on 24 October and MRI on 2 November show the development of the pathology up to the disappearance of the modified

Figure 22: RMN images of Second degree lesion in a professional footballer

Figure 23: RMN images of Second degree lesion in a professional footballer Professional footballer who felt a harp pain in the groin after a match but was able despite

the pain to carry out differentiated training for four-five days.

<sup>F</sup>

<sup>F</sup>

Major League footballer who felt a very sharp pain in a sprint on 29 September.

Major League footballer who felt a very sharp pain in a sprint on 29 September.

**Figure 20.** RMN images of Second degree lesion in a professional footballer

miotendon injury of the Semimembranosus. (Fig.19)

**Figure 21.** US image of Second degree lesion in a professional footballer

signal in MRI as from recovery. (Fig.22)

Example of a professional footballer

**Case 6**

tendon injury and intratendon tear too. (Fig.20)

**Case 4** 

**Case 5**

Example of a professional footballer

area (>5 cm) with large haemorrhage.

Example of a professional footballer

114 Muscle Injuries in Sport Medicine

Figure 22: RMN images of Second degree lesion in a professional footballer

Figure 23: RMN images of Second degree lesion in a professional footballer Professional footballer who felt a harp pain in the groin after a match but was able despite

the pain to carry out differentia **Figure 23.** RMN images of Second degree lesion in a professional footballer ted training for four-five days.

Example of a professional footballer

Professional footballer who felt a harp pain in the groin after a match but was able despite the pain to carry out differentiated training for four-five days. Example of a professional footballer

The pain persisted so after a negative Ultrasound MRI was carried Figure 23.RMN images of Second degree lesion in a professional footballer

This highlighted a large serum-haemorragic area characterized by clear signal hyperintensity as from second degree injury of the QuadratusFemoris and of the Inferior Gemellus. (Fig.23) Professional footballer who felt a harp pain in the groin after a match but was able despite the pain to carry out differentiated training for four‐five days. Figure 23.RMN images of Second degree lesion in a professional footballer

#### **Case 7** This highlighted a large serum‐haemorragic area characterized by clear signal hyperintensity as from second degree injury of the Professional footballer who felt a harp pain in the groin after a match but was able despite the pain to carry out differentiated

training for four‐five days.

**Case 7**

**Case 7**

up.

up.

( Fig.24 )

**Case 6**

**Case 6**

Example of a professional footballer Quadratus Femoris and of the Inferior Gemellus.( Fig.23 )

Quadratus Femoris and of the Inferior Gemellus.( Fig.23 )

The pain persisted so after a negative Ultrasound MRI was carried

The pain persisted so after a negative Ultrasound MRI was carried

This highlighted a large serum‐haemorragic area characterized by clear signal hyperintensity as from second degree injury of the

Figure 24: US images of Second degree lesion in a professional footballer

<sup>F</sup>

Example of a professional footballer who felt sharp pain in the calf during pre-match warm

Professional footballer who felt a harp pain in the groin after a match but was able despite the pain to carry out differentiated

This highlighted a large serum‐haemorragic area characterized by clear signal hyperintensity as from second degree injury of the

<sup>F</sup>

Diagnostic Imaging in Muscle Injury http://dx.doi.org/10.5772/56472 117

<sup>F</sup>

Ultrasound highlighted a single intramuscular anaechoic area (>5 cm) with large haemorrhage as from isolated second degree

Because of an unclear diagnosi MRI was carried out which showed a double area with dishomogeneous signal hyperintensity due to interstitial and perifascial oedema together with haemorrhage as from a double second degree injury of the Soleus muscle.(

<sup>F</sup>

Ultrasound highlighted a single intramuscular anaechoic area (>5 cm) with large haemorrhage

Because of an unclear diagnosi MRI was carried out which showed a double area with dishomogeneous signal hyperintensity due to interstitial and perifascialoedema together with

Example of a professional footballer who felt sharp pain in the calf during pre‐match warm up.

haemorrhage as from a double second degree injury of the Soleus muscle. (Fig.25)

as from isolated second degree injury of the Soleus muscle. (Fig.24)

Figure 25.RMN images of Second degree lesion in a professional footballer

Figure 24.US images of Second degree lesion in a professional footballer

Figure 23.RMN images of Second degree lesion in a professional footballer

The pain persisted so after a negative Ultrasound MRI was carried

Quadratus Femoris and of the Inferior Gemellus.( Fig.23 )

These images are typical of a complex second degree injury

These images are typical of a complex second degree injury

Figure 26.RMN images of Second degree lesion in a professional footballer **Figure 26.** RMN images of Second degree lesion in a professional footballer

Professional footballer who felt a sharp pain during pre-season camp.

miotendon second degree injury of the Rectus Femoris muscle.

modified signal in MRI as from recovery. (Fig.27)

Example of a professional footballer

sharp pain in the quadriceps.

An initial Ultrasound (not published here) highlighted a large anaechoic area (>5 cm) as from

MRI showed relevant signal hyperintensity due to oedema together with haemorrhage as from second degree injury of the Anterior or Straight Tendon of RectusFemoris muscle. (Fig.26)

Follow-up MRIs show the development of the pathology up to the disappearance of the

Professional footballer who came for Ultrasound a few days after kicking a goal and feeling a

Example of a professional football player

Example of a professional football player

injury of the Soleus muscle.( Fig.24 )

up.

**Case 6**

**Case 7**

Example of a professional footballer

training for four‐five days.

Example of a professional footballer

**Case 8**

**Caso 9**

Fig.25 )

**Case 8** 

<sup>F</sup>

**Figure 24.** US images of Second degree lesion in a professional footballer

Figure 25: RMN images of Second degree lesion in a professional footballer

Ultrasound highlighted a single intramuscular anaechoic area (>5 cm) with large

haemorrhage as from isolated second degree injury of the Soleus muscle. ( Fig.24 ) Example of a professional footballer who felt sharp pain in the calf during pre-match warm **Figure 25.** RMN images of Second degree lesion in a professional footballer

haemorrhage as from isolated second degree injury of the Soleus muscle.

Example of a professional footballer who felt sharp pain in the calf during pre-match warm up.

Professional footballer who felt a harp pain in the groin after a match but was able despite the pain to carry out differentiated

This highlighted a large serum‐haemorragic area characterized by clear signal hyperintensity as from second degree injury of the

<sup>F</sup>

Ultrasound highlighted a single intramuscular anaechoic area (>5 cm) with large haemorrhage as from isolated second degree injury of the Soleus muscle. (Fig.24) <sup>F</sup> Figure 25.RMN images of Second degree lesion in a professional footballer

Because of an unclear diagnosi MRI was carried out which showed a double area with dishomogeneous signal hyperintensity due to interstitial and perifascialoedema together with haemorrhage as from a double second degree injury of the Soleus muscle. (Fig.25) Example of a professional footballer who felt sharp pain in the calf during pre‐match warm up. Ultrasound highlighted a single intramuscular anaechoic area (>5 cm) with large haemorrhage as from isolated second degree injury of the Soleus muscle.( Fig.24 )

These images are typical of a complex second degree injury Because of an unclear diagnosi MRI was carried out which showed a double area with dishomogeneous signal hyperintensity due to interstitial and perifascial oedema together with haemorrhage as from a double second degree injury of the Soleus muscle.(

**Case 8**

Fig.25 )

**Case 8** 

**Case 6**

**Case 7**

Example of a professional footballer

training for four‐five days.

Example of a professional footballer

Figure 23.RMN images of Second degree lesion in a professional footballer

The pain persisted so after a negative Ultrasound MRI was carried

Quadratus Femoris and of the Inferior Gemellus.( Fig.23 )

Figure 24.US images of Second degree lesion in a professional footballer

<sup>F</sup>

<sup>F</sup>

<sup>F</sup>

<sup>F</sup>

Professional footballer who felt a harp pain in the groin after a match but was able despite the

This highlighted a large serum-haemorragic area characterized by clear signal hyperintensity as from second degree injury of the QuadratusFemoris and of the Inferior Gemellus. (Fig.23)

This highlighted a large serum‐haemorragic area characterized by clear signal hyperintensity as from second degree injury of the

This highlighted a large serum‐haemorragic area characterized by clear signal hyperintensity as from second degree injury of the

Professional footballer who felt a harp pain in the groin after a match but was able despite the pain to carry out differentiated

Figure 24: US images of Second degree lesion in a professional footballer

Figure 24: US images of Second degree lesion in a professional footballer

Figure 25: RMN images of Second degree lesion in a professional footballer Example of a professional footballer who felt sharp pain in the calf during pre-match warm

Ultrasound highlighted a single intramuscular anaechoic area (>5 cm) with large

Ultrasound highlighted a single intramuscular anaechoic area (>5 cm) with large

Figure 25: RMN images of Second degree lesion in a professional footballer Example of a professional footballer who felt sharp pain in the calf during pre-match warm

haemorrhage as from isolated second degree injury of the Soleus muscle.

**Figure 25.** RMN images of Second degree lesion in a professional footballer

haemorrhage as from isolated second degree injury of the Soleus muscle.

Professional footballer who felt a harp pain in the groin after a match but was able despite the pain to carry out differentiated

pain to carry out differentiated training for four-five days.

**Figure 24.** US images of Second degree lesion in a professional footballer

Example of a professional footballer

Quadratus Femoris and of the Inferior Gemellus.( Fig.23 )

Quadratus Femoris and of the Inferior Gemellus.( Fig.23 )

Figure 23.RMN images of Second degree lesion in a professional footballer

The pain persisted so after a negative Ultrasound MRI was carried

The pain persisted so after a negative Ultrasound MRI was carried

Figure 23.RMN images of Second degree lesion in a professional footballer

**Case 7**

**Case 7**

**Case 7**

up.

up.

( Fig.24 )

( Fig.24 )

training for four‐five days.

training for four‐five days.

Example of a professional footballer

Example of a professional footballer

**Case 6**

**Case 6**

Example of a professional footballer

116 Muscle Injuries in Sport Medicine

Example of a professional footballer

The pain persisted so after a negative Ultrasound MRI was carried

Example of a professional football player These images are typical of a complex second degree injury

Example of a professional football player

Figure 26.RMN images of Second degree lesion in a professional footballer **Figure 26.** RMN images of Second degree lesion in a professional footballer

Professional footballer who felt a sharp pain during pre-season camp.

An initial Ultrasound (not published here) highlighted a large anaechoic area (>5 cm) as from miotendon second degree injury of the Rectus Femoris muscle.

MRI showed relevant signal hyperintensity due to oedema together with haemorrhage as from second degree injury of the Anterior or Straight Tendon of RectusFemoris muscle. (Fig.26)

Follow-up MRIs show the development of the pathology up to the disappearance of the modified signal in MRI as from recovery. (Fig.27)

#### **Caso 9**

Example of a professional footballer

Professional footballer who came for Ultrasound a few days after kicking a goal and feeling a sharp pain in the quadriceps.

Fig.27 )

Figure 27: RMN images of Second degree lesion in a professional footballer

28

28

28

**Caso 9** 

Example of a professional footballer

Figure 28: US images of Second degree lesion in a professional footballer

**Caso 9** 

Diagnostic Imaging in Muscle Injury http://dx.doi.org/10.5772/56472 119

Example of a professional footballer

**Caso 9** 

Example of a professional footballer

Figure 28: US images of Second degree lesion in a professional footballer

Figure 28: US images of Second degree lesion in a professional footballer

Ultrasound showed a large anechoic area of structural alteration due to haemorrhage with distancing of muscular extremities as from second degree injury of Posterior or Reflected

Subsequent MRI (Fig.29-30-31) and Ultrasound (Fig.32) show the development of the pathol‐

Figure 29: Rmn 11-11 in stir without Gadolinium

Figure 29: Rmn 11-11 in stir without Gadolinium

Figure 30: Rmn 11-11 in T1 without Gadolinium

Figure 29: Rmn 11-11 in stir without Gadolinium

ogy up to disappearance of the modified signal in MRI as from recovery.

**Figure 28.** US images of Second degree lesion in a professional footballer

Tendon. (Fig.28)

Figure 30: Rmn 11-11 in T1 without Gadolinium

**Figure 30.** Rmn 11-11 in T1 without Gadolinium Figure 30: Rmn 11-11 in T1 without Gadolinium

**Figure 29.** Rmn 11-11 in stir without Gadolinium

MRI showed relevant signal hyperintensity due to oedema together with haemorrhage as from second degree injury of the

Follow‐up MRIs show the development of the pathology up to the disappearance of the modified signal in MRI as from recovery.(

**Figure 27.** RMN images of Second degree lesion in a professional footballer

28

28

Figure 28: US images of Second degree lesion in a professional footballer

**Caso 9** 

Example of a professional footballer

**Figure 28.** US images of Second degree lesion in a professional footballer Example of a professional footballer

Figure 29: Rmn 11-11 in stir without Gadolinium

MRI showed relevant signal hyperintensity due to oedema together with haemorrhage as from second degree injury of the

Follow‐up MRIs show the development of the pathology up to the disappearance of the modified signal in MRI as from recovery.(

24‐7

30‐7

Figure 27: RMN images of Second degree lesion in a professional footballer

Anterior or Straight Tendon of Rectus Femoris muscle.( Fig.26 )

13‐8

27‐8

**Figure 27.** RMN images of Second degree lesion in a professional footballer

Fig.27 )

118 Muscle Injuries in Sport Medicine

Ultrasound showed a large anechoic area of structural alteration due to haemorrhage with distancing of muscular extremities as from second degree injury of Posterior or Reflected Tendon. (Fig.28)

Subsequent MRI (Fig.29-30-31) and Ultrasound (Fig.32) show the development of the pathol‐ ogy up to disappearance of the modified signal in MRI as from recovery.

Figure 28: US images of Second degree lesion in a professional footballer

Example of a professional footballer

Figure 30: Rmn 11-11 in T1 without Gadolinium Figure 29: Rmn 11-11 in stir without Gadolinium **Figure 29.** Rmn 11-11 in stir without Gadolinium

Figure 29: Rmn 11-11 in stir without Gadolinium

**Figure 30.** Rmn 11-11 in T1 without Gadolinium Figure 30: Rmn 11-11 in T1 without Gadolinium

**Figure 31.** Rmn 3-12

```
Figure 32. US 3-12
```
#### **3.6. Third degree injury**

Third degree injuries are defined as Subtotal with a tear of a higher number of fibres in the muscle (>70%, > 2/3 of the muscle belly) or Total with a tear of the whole muscle belly.

In the acute stage the Ultrasound highlighted a clearly dishomogeneous and disorganized isohyperechoic area, whilst in the sub-acute stage a clearly dishomogeneous area with marked structural change was revealed together with retraction of the stumps and a large anaechoic inter or intramuscular area (usually>3cm) depending of the size of the muscle.

30

Diagnostic Imaging in Muscle Injury http://dx.doi.org/10.5772/56472 121

30

retraction of the stumps and a large anaechoic inter or intramuscular area

MRI instead revealed a retraction of the stumps which showed irregular, wavy edges and hyperintense mass of fluid due to the haemorrhage between the two

**Case 1**

retraction of the stumps and a large anaechoic inter or intramuscular area

Example of a professional rugby player

MRI instead revealed a retraction of the stumps which showed irregular, wavy edges and hyperintense mass of fluid due to the haemorrhage between the two

Figure 33: US images of Third degree lesion in a professional rugby player

**Case 1**

Example of a professional rugby player

Example of a professional rugby player who came for Ultrasound to his arm after prolonged tackle. A large anechoic area was revealed due to haematoma associated to retraction of the

Figure 34: US images of Third degree lesion in a professional footballer

Figure 33: US images of Third degree lesion in a professional rugby player

Example of a young goalkeeper who after a kick felt a sharp pain in the upper

MRI highlighted a haematoma shown by a hyperintense area associated to miotendon retraction as from sub-total tear of the Rectus Femoris Tendon .(

**Case 3**

Example of a young goalkeeper who after a kick felt a sharp pain in the upper thigh as if from

Example of a young goalkeeper who after a kick felt a sharp pain in the upper

MRI highlighted a haematoma shown by a hyperintense area associated to miotendon retraction as from sub-total tear of the Rectus Femoris Tendon .(

**Case 3**

MRI highlighted a haematoma shown by a hyperintense area associated to miotendon

Figure 34: US images of Third degree lesion in a professional footballer

Ultrasound showed a small haemorrage as from miotend injury.

Ultrasound showed a small haemorrage as from miotend injury.

muscle head as from a complete tear of the Proximal Biceps Brachii. (Fig.33)

However symptoms led to a more severe injury.

However symptoms led to a more severe injury.

Ultrasound showed a small haemorrage as from miotend injury.

retraction as from sub-total tear of the Rectus Femoris Tendon. (Fig.34)

**Figure 34.** US images of Third degree lesion in a professional footballer

**Figure 33.** US images of Third degree lesion in a professional rugby player

thigh as if from hip dislocation.

thigh as if from hip dislocation.

Example of a professional footballer

However symptoms led to a more severe injury.

Example of a professional footballer

Fig.34 )

Fig.34 )

**Case 3**

hip dislocation.

**Case 2**

(usually>3cm) depending of the size of the muscle.

(usually>3cm) depending of the size of the muscle.

stumps.

stumps.

MRI instead revealed a retraction of the stumps which showed irregular, wavy edges and hyperintense mass of fluid due to the haemorrhage between the two stumps.

#### **Case 1**

Example of a professional rugby player

retraction of the stumps and a large anaechoic inter or intramuscular area

MRI instead revealed a retraction of the stumps which showed irregular, wavy edges and hyperintense mass of fluid due to the haemorrhage between the two

**Case 1**

Example of a professional rugby player

(usually>3cm) depending of the size of the muscle.

(usually>3cm) depending of the size of the muscle.

Figure 33: US images of Third degree lesion in a professional rugby player **Figure 33.** US images of Third degree lesion in a professional rugby player

Example of a professional rugby player who came for Ultrasound to his arm after prolonged tackle. A large anechoic area was revealed due to haematoma associated to retraction of the muscle head as from a complete tear of the Proximal Biceps Brachii. (Fig.33)

#### **Case 2**

stumps.

**Figure 31.** Rmn 3-12

120 Muscle Injuries in Sport Medicine

**Figure 32.** US 3-12

**Case 1**

**3.6. Third degree injury**

Example of a professional rugby player

Third degree injuries are defined as Subtotal with a tear of a higher number of fibres in the muscle (>70%, > 2/3 of the muscle belly) or Total with a tear of the whole muscle belly.

In the acute stage the Ultrasound highlighted a clearly dishomogeneous and disorganized isohyperechoic area, whilst in the sub-acute stage a clearly dishomogeneous area with marked structural change was revealed together with retraction of the stumps and a large anaechoic

MRI instead revealed a retraction of the stumps which showed irregular, wavy edges and

inter or intramuscular area (usually>3cm) depending of the size of the muscle.

hyperintense mass of fluid due to the haemorrhage between the two stumps.

Example of a professional footballer

Figure 33: US images of Third degree lesion in a professional rugby player

**Case 3** Example of a young goalkeeper who after a kick felt a sharp pain in the upper **Figure 34.** US images of Third degree lesion in a professional footballer

30 thigh as if from hip dislocation. Ultrasound showed a small haemorrage as from miotend injury. Example of a young goalkeeper who after a kick felt a sharp pain in the upper thigh as if from hip dislocation.

Figure 34: US images of Third degree lesion in a professional footballer

However symptoms led to a more severe injury. MRI highlighted a haematoma shown by a hyperintense area associated to Ultrasound showed a small haemorrage as from miotend injury.

miotendon retraction as from sub-total tear of the Rectus Femoris Tendon .( However symptoms led to a more severe injury.

Fig.34 ) **Case 3** MRI highlighted a haematoma shown by a hyperintense area associated to miotendon retraction as from sub-total tear of the Rectus Femoris Tendon. (Fig.34)

#### **Case 3**

Example of a professional footballer

Example of a professional footballer

**Figure 35.** US images of Third degree lesion in a professional footballer

Example of a footballer who after a kick felt a very sharp pain in the groin.

Ultrasound showed a large anaechoic area due to haematoma with retraction of the muscle head as from complete third degree tear of the Adductor Longus muscle. (Fig.35)

#### **Case 4**

Example of a professional footballer Figure 35: US images of Third degree lesion in a professional footballer

Figure 36: US images of Third degree lesion in a professional footballer

**Figure 36.** US images of Third degree lesion in a professional footballer

Example of a footballer who after a kick felt a very sharp pain in the upper thigh. Example of a footballer who after a kick felt a very sharp pain in the upper thigh.

Ultrasound showed a large haematoma with retraction of the muscle head as from complete third degree tear of the Rectus Femoris.( Fig.36 ) Ultrasound showed a large haematoma with retraction of the muscle head as from complete third degree tear of the Rectus Femoris. (Fig.36)

31

32

**Case 5** 

Diagnostic Imaging in Muscle Injury http://dx.doi.org/10.5772/56472 123

Example of a professional rugby player

Figure 37: US images of Third degree lesion in a professional rugby player

Example of a professional rugby player who came for Ultrasound to his arm

Example of a professional rugby player who came for Ultrasound to his arm after prolonged

A large anechoic area was revealed due to haematoma associated to retraction of the muscle

This typically are injuries by contusion followed by hoematoma which by ultrasound revealed

head as from a complete tear of the Tendon of the Pectorali Major muscle. (Fig.37)

after prolonged tackle.

**3.7. Direct muscular injuries**

no difference from intrinsic hoematoma

tackle.

**Figure 37.** US images of Third degree lesion in a professional rugby player

31

#### **Case 5**

Example of a professional rugby player

**Case 5** 

Example of a professional rugby player

Figure 37: US images of Third degree lesion in a professional rugby player **Figure 37.** US images of Third degree lesion in a professional rugby player

Example of a professional rugby player who came for Ultrasound to his arm after prolonged tackle.

Example of a professional rugby player who came for Ultrasound to his arm

A large anechoic area was revealed due to haematoma associated to retraction of the muscle head as from a complete tear of the Tendon of the Pectorali Major muscle. (Fig.37)

#### **3.7. Direct muscular injuries**

after prolonged tackle.

31

31

Example of a professional footballer

Figure 35: US images of Third degree lesion in a professional footballer

Example of a professional footballer

Ultrasound showed a large anaechoic area due to haematoma with retraction of the muscle

**Figure 35.** US images of Third degree lesion in a professional footballer

Example of a professional footballer

Figure 36: US images of Third degree lesion in a professional footballer

Figure 35: US images of Third degree lesion in a professional footballer

Example of a footballer who after a kick felt a very sharp pain in the upper

Ultrasound showed a large haematoma with retraction of the muscle head as

Figure 36: US images of Third degree lesion in a professional footballer

Example of a footballer who after a kick felt a very sharp pain in the upper

Ultrasound showed a large haematoma with retraction of the muscle head as

Ultrasound showed a large haematoma with retraction of the muscle head as from complete

from complete third degree tear of the Rectus Femoris.( Fig.36 )

**Figure 36.** US images of Third degree lesion in a professional footballer

third degree tear of the Rectus Femoris. (Fig.36)

Example of a professional rugby player

from complete third degree tear of the Rectus Femoris.( Fig.36 )

Example of a footballer who after a kick felt a very sharp pain in the upper thigh.

Example of a footballer who after a kick felt a very sharp pain in the groin.

head as from complete third degree tear of the Adductor Longus muscle. (Fig.35)

thigh.

thigh.

**Case 5**

**Case 4**

122 Muscle Injuries in Sport Medicine

This typically are injuries by contusion followed by hoematoma which by ultrasound revealed no difference from intrinsic hoematoma

muscle.( Fig.37 )

Only a correct history of the injury can help in understanding the stages in the level of the fluid. Only a correct history of the injury can help in understanding the stages in the level of the fluid.

 **Case 1** 

Example of a professional footballer

ultrasound revealed no difference from intrinsic hoematoma

**Direct Muscular Injuries** 

A large anechoic area was revealed due to haematoma associated to retraction of the muscle head as from a complete tear of the Tendon of the Pectorali Major

#### **Case 1**

Example of a professional footballer

**Figure 38.** US image of lesion due to a contusion in a professional footballer

Example of a goalkeeper who during jump was hit with a knee on his thigh Example of a goalkeeper who during jump was hit with a knee on his thigh receving a contusion and subsuequent injury of the VastusIntermedius muscle

Differently from the classification above a definition of muscle injury complication appears to

The Ultrasound revealed a large anaechoic area of the Obliquus Abdominis

Figure 39: US image of lesion due to a contusion in a professional footballer

**Figure 39.** US image of lesion due to a contusion in a professional footballer

Example of a goalkeeper who during jump was kicked in the side of his abdomen receving a contusion and subsuequent injury of the Obliquus

**Case 2** 

Diagnostic Imaging in Muscle Injury http://dx.doi.org/10.5772/56472 125

Example of a professional footballer

It reduces the muscle elastic and functional capacities (the capacity to develop strength) as it

34

It is usually caused by early mobilisation or prolonged immobilisation with excessive forma‐ tion of abnormal, hypertrophic retracting fibrous tissue which affect the functionality of the

be universally recognized and more simple.

**•** Intermuscular fluid collection

Abdominis Muscle

It is the most frequent complication.

replaces the normal tissue.

muscular area involved.

**•** Cyst sero-sanguineus

Muscle.( Fig.39 )

**•** Ossific myositis **•** Muscular atrophia

**4.1. Fibrosis**

These include:

**•** Fibrosis

Figure 38: US image of lesion due to a contusion in a professional footballer

receving a contusion and subsuequent injury of the Vastus Intermedius muscle The Ultrasound revealed a large anaechoic area. (Fig.38)

#### The Ultrasound revealed a large anaechoic area.( Fig.38 ) **Case 2**

Example of a professional footballer

Example of a goalkeeper who during jump was kicked in the side of his abdomen receving a contusion and subsuequent injury of the ObliquusAbdominis Muscle

33 The Ultrasound revealed a large anaechoic area of the ObliquusAbdominis Muscle. (Fig.39)
