**3. Methods**

#### **3.1 Indications for disc repositioning**

Meniscopexy has been indicated in cases of anterior displacement of the TMJ articular disc without reduction, in an effort to slow progression to more advanced TMJ-related symptoms [16]. There are, however, a range of various surgical techniques that may be employed for TMD management, thus it is important to delineate where meniscopexy may be used in preference to these. Disc repositioning is favoured in patients who have not responded to initial non-surgical treatment [17] or diagnostic arthroscopy/arthrocentesis [18].

Studies have also attempted to identify causes of TMD that may have a more favourable surgical outcome with meniscopexy. One prospective cohort study looked at the stage of internal derangement of the articular disc according to the Wilkes classification as a factor in determining success using Meniscopexy in management. Patients had previously undergone both conservative and primary arthroscopic treatment with lysis and lavage of the superior joint space. Patients were classified into two groups, Wilkes Stages II and III and Wilkes Stages IV and

**107**

**3.2 Surgical technique**

[3, 14, 17, 32]

arthroscopic surgery [16].

within our search) [16, 19, 22, 23]

*Review of Current Practice for Temporomandibular Joint Meniscopexy Surgery*

II/III group in comparison to 25% for the Wilkes IV/V group [18].

V and underwent arthroscopic disc repositioning surgery to reduce and fix the articular disc. The primary successful outcome was determined by absence of pain at 12 months postoperatively. The study found an 86.7% success rate for the Wilkes

stages of internal derangement, but less successful with increasing degenerative changes of the TMJ. A literature review of discectomy versus preservation of the articular disc evaluated current evidence to determine a rationale for meniscopexy versus removal/replacement of the disc. Adequate remaining anatomy and mobility of the disc, with minimal damage or perforation was key to the decision to preserve [19, 20]. Surgical management of disc displacement without reduction arising acutely

following facial trauma without condylar fracture where no TMJ symptoms existed prior to the event was evaluated. Evidence suggests that there is a more rapid progression of disease following acute displacement. There is a much weaker response to conservative treatment and greater chance of developing osteoarthiritis or even ankylosis of the joint, with fast degeneration of the condyle within the first 3 months. Such adverse degenerative changes in some patients would justify surgical intervention at an earlier stage rather than prolonged conservative treatment as first line management where necessary. Eight8 patients were offered disc repositioning surgery and seven total joint replacement following rapid onset of end-stage disease. The study observed patients following trauma, after both conservative treatment and surgery. All patients demonstrated limited maximum interincisal opening (MIO) and deterioration of the condyle as seen on MRI following initial conservative treatment, with significant improvement in MIO post-operatively [21].

This suggests meniscopexy as being an effective means of management for earlier

Studies like this are useful in demonstrating the place for meniscopexy within the surgical armamentarium when managing TMDs. They give an appreciation where the procedure is most effective and can be indicated as a first line of approach. From the literature search there are no studies available that investigate the efficacy of meniscopexy over other techniques at various stages of disease. More data is required to inform surgeons of circumstances where meniscopexy has the best outcome.

There are multiple surgical approaches described in the literature to TMJ articu-

• Meniscopexy through an open incision or arthrotomy (described in 4 articles

Disc repositioning techniques first developed, such as that initially described by McCarty and Farrar in 1988, rely on an endaural open incision to access the TMJ, which remains to be the approach of choice for many surgeons. Dissection is carried out to access the disc and is released anteriorly, repositioned and subsequently sutured, either to the capsule or auricular cartilage. This technique is favoured by many due to its relative ease, providing a better view of the disc and its attachments, making the anterior release and suturing of the disc more predictable, compared to

• Meniscopexy with the use of suture anchors or mini-anchors to aid disc fixation (described in 10 articles within our search) [13, 15, 24–31]

• Arthroscopic meniscopexy (described in 4 articles within our search)

lar disc repositioning, which can be broadly classified into three areas:

*DOI: http://dx.doi.org/10.5772/intechopen.93403*

#### *Review of Current Practice for Temporomandibular Joint Meniscopexy Surgery DOI: http://dx.doi.org/10.5772/intechopen.93403*

V and underwent arthroscopic disc repositioning surgery to reduce and fix the articular disc. The primary successful outcome was determined by absence of pain at 12 months postoperatively. The study found an 86.7% success rate for the Wilkes II/III group in comparison to 25% for the Wilkes IV/V group [18].

This suggests meniscopexy as being an effective means of management for earlier stages of internal derangement, but less successful with increasing degenerative changes of the TMJ. A literature review of discectomy versus preservation of the articular disc evaluated current evidence to determine a rationale for meniscopexy versus removal/replacement of the disc. Adequate remaining anatomy and mobility of the disc, with minimal damage or perforation was key to the decision to preserve [19, 20].

Surgical management of disc displacement without reduction arising acutely following facial trauma without condylar fracture where no TMJ symptoms existed prior to the event was evaluated. Evidence suggests that there is a more rapid progression of disease following acute displacement. There is a much weaker response to conservative treatment and greater chance of developing osteoarthiritis or even ankylosis of the joint, with fast degeneration of the condyle within the first 3 months. Such adverse degenerative changes in some patients would justify surgical intervention at an earlier stage rather than prolonged conservative treatment as first line management where necessary. Eight8 patients were offered disc repositioning surgery and seven total joint replacement following rapid onset of end-stage disease. The study observed patients following trauma, after both conservative treatment and surgery. All patients demonstrated limited maximum interincisal opening (MIO) and deterioration of the condyle as seen on MRI following initial conservative treatment, with significant improvement in MIO post-operatively [21].

Studies like this are useful in demonstrating the place for meniscopexy within the surgical armamentarium when managing TMDs. They give an appreciation where the procedure is most effective and can be indicated as a first line of approach. From the literature search there are no studies available that investigate the efficacy of meniscopexy over other techniques at various stages of disease. More data is required to inform surgeons of circumstances where meniscopexy has the best outcome.

#### **3.2 Surgical technique**

*Oral and Maxillofacial Surgery*

• Meniscoplasty

**Table 3.**

• Disc Repositioning

yield 23 relevant papers. Inclusion criteria:

28/10/2008)

**3. Methods**

• Articles must be peer-reviewed

tive studies and 6 technical notes.

**3.1 Indications for disc repositioning**

or diagnostic arthroscopy/arthrocentesis [18].

• Articles must be written in English

We further scrutinised the list of papers using our inclusion criteria (below) to

*Articles found within literature search classified by type (published between 28/10/2008 and 28/10/2019).*

• Articles must be less than 11 years old (i.e., all articles published after

Excluded papers were patents, letters, articles not pertaining to meniscopexy treatment, articles not in the English language and those outside the stated timeline. Of the 23 papers, we found 3 review articles, 12 retrospective studies, 2 prospec-

Meniscopexy has been indicated in cases of anterior displacement of the TMJ articular disc without reduction, in an effort to slow progression to more advanced TMJ-related symptoms [16]. There are, however, a range of various surgical techniques that may be employed for TMD management, thus it is important to delineate where meniscopexy may be used in preference to these. Disc repositioning is favoured in patients who have not responded to initial non-surgical treatment [17]

Studies have also attempted to identify causes of TMD that may have a more favourable surgical outcome with meniscopexy. One prospective cohort study looked at the stage of internal derangement of the articular disc according to the Wilkes classification as a factor in determining success using Meniscopexy in management. Patients had previously undergone both conservative and primary arthroscopic treatment with lysis and lavage of the superior joint space. Patients were classified into two groups, Wilkes Stages II and III and Wilkes Stages IV and

• Articles must be directly relevant to the to be evaluated

**Type No. of Articles (%)** Review 3 (13) Technical Note 6 (26) Retrospective 12 (52) Prospective 2 (9)

• Quantitative and Qualitative studies can be included

**106**

There are multiple surgical approaches described in the literature to TMJ articular disc repositioning, which can be broadly classified into three areas:


Disc repositioning techniques first developed, such as that initially described by McCarty and Farrar in 1988, rely on an endaural open incision to access the TMJ, which remains to be the approach of choice for many surgeons. Dissection is carried out to access the disc and is released anteriorly, repositioned and subsequently sutured, either to the capsule or auricular cartilage. This technique is favoured by many due to its relative ease, providing a better view of the disc and its attachments, making the anterior release and suturing of the disc more predictable, compared to arthroscopic surgery [16].

Modifications of this technique have been introduced, with the use of mini suture anchors screwed into the condyle, in the hope of achieving better long-term fixation and stability of the reduced disc. A variety of orthopaedic suture anchors have been used for this purpose, most commonly the Mitek [29] and Arthrex mini-anchors [15], however alternatives have also demonstrated success, such as one study that reports the use of orthodontic mini-screws [24]. Such techniques aim to offer a predictable long-term result, however, may not be most appropriate where it is difficult to insert a screw into the condyle, such as in the small, resorbed or osteoporotic condyle [16].

Arthroscopic repositioning of the disc and suturing provides an alternative to procedures involving an open incision. Arthroscopy is a more minimally invasive approach, permitting the selective operation on articular disc without causing damage to the other tissues of the TMJ, as well as reducing risk of iatrogenic facial nerve injury which can be associated with open surgery (arthrotomy). Surgically, this involves the creation of three portals, one for the arthroscope and two for instrumentation permitting the passing of a suture through the disc. This technique, despite its conservative nature, is mainly limited by its technical difficulty, and is best performed by an experienced surgeon to ensure a long-term stable outcome [16, 17, 32].

One article also reported the use of a modified meniscopexy technique, whereby a splint was used by patients for a period before surgery, opening the joint space. An anterior-repositioning splint was during the surgical procedure to place the mandible into an ideal relationship with the maxilla. The disc is finally repositioned and sutured anteriorly and laterally to the capsular ligament using an open preauricular approach. Patients then wear the splint postoperatively which is gradually made smaller and narrower, slowly reducing the joint space to its normal anatomical size with the aim of reducing displacement or relapse of the disc repositioning [22].

#### **3.3 Outcome variables**

Several outcome variables were used as measures post-surgery. These included maximal interincisal opening (MIO), post-operative pain using the visual analogue scale (VAS) or questionnaire, changes in diet consistency, mandibular range of motion, joint clicking (including other noises), the use of medications, joint loading signs, MRI to evaluate disc position, disc rupture, and muscular pain.

#### *3.3.1 Maximal Interincisal opening (MIO)*

MIO is the measurement of the distance between the incisal edges of maxillary central incisors to mandibular central incisors at maximum mouth opening. During anterior disc displacement, mandibular opening becomes limited, thus corrective meniscopexy should increase mouth opening in successful cases allowing MIO to be an indicator for success (**Table 4**).

When comparing the different techniques used in the studies, the greatest increase in mean MIO was seen for patients who had undergone arthrotomy using Mitek mini-anchors compared to arthroscopic techniques [17, 18, 21, 26, 28]. However, it should be noted that the severity of TMD within the patient cohorts is likely to differ, with higher Wilkes' classifications having further disc degeneration and thus limited mouth opening. Further to this, cohort size has implications on reliability of the results, with smaller cohorts being less reliable to compare surgical techniques based on outcomes. Rajkumar et al. found that MIO increased most significantly, in patients with disc displacement without reduction (DDwoR), within the first month after surgery, with significantly smaller increases seen up to 6 months post-operatively. Although it is difficult to compare between these studies

**109**

*3.3.2 Pain*

*Review of Current Practice for Temporomandibular Joint Meniscopexy Surgery*

**of patients** **Preoperative MIO mean (mm)**

**Postoperative MIO mean (mm)**

8/7 19.8 33.9 Not specified

32 30.0 37.9 12 months

50 23.5 38.3 Not

16 31.1 39.9 12 months

7 22.8 31.5 12 months

39.6

25.6 35.0

**Follow-up period (time post-op)**

specified

1 month 6 months

**Technique Number** 

due to differing techniques used and other difference in key variables, similar trends can be seen from the values provided, highlighting the importance of correct

3 patients with DDwoR\*

marised in the table as average values within the patient cohorts (**Table 5**).

Pain can be used as a subjective measure of surgical outcomes. Within the studies we looked at, there were three methods of measuring pain: using a questionnaire to give a pain score out of 10, using the Visual Analogue Scale (VAS) or by reporting the percentage of patients with pain pre and post operatively. These have been sum-

Overall, all studies showed an improvement in pain scores on follow up. The VAS was the most commonly used measure of quantifying pain improvement post-operatively. This can be said to be due to its relative simplicity and quantitative nature. However, there has been debate with regards to its validity. Patients may report pain with a certain degree of bias and also may not be able to report pain relief reliably owing to difficulties in recalling previous pain experiences, hence quantitative comparison is challenging [33]. Some studies looked at the simple absence/presence of pain: Ruiz Valero et al. demonstrated a significantly smaller number of patients presenting with painful TMJ symptoms 12 months post-operatively (pre-100%, post-8%). McCain et al. also looked at pain medication use among patients at pre-operative assessment (15/32 patients) and at last visit (6/32) as a secondary

disc position in mechanical action of the mandible.

*DOI: http://dx.doi.org/10.5772/intechopen.93403*

Disc repositioning/ Total joint replacement

Arthroscopic suture meniscopexy

Open Meniscopexy using Mitek anchors

Arthroscopic Meniscopexy using posterior double pass suture

Open Meniscopexy using Mitek anchors

Open Meniscopexy with orthodontic anchors

*DDwoR, disc displacement without reduction.*

*Pre-operative and post-operative mouth opening.*

**Name of study**

He et al. [21]

McCain et al. [18]

Ruiz Valero et al. [28]

Goizueta Adame et al. [17]

Göçmen et al. [26]

Rajkumar et al. [24]

*\**

**Table 4.**


*Review of Current Practice for Temporomandibular Joint Meniscopexy Surgery DOI: http://dx.doi.org/10.5772/intechopen.93403*

#### **Table 4.**

*Oral and Maxillofacial Surgery*

or osteoporotic condyle [16].

**3.3 Outcome variables**

*3.3.1 Maximal Interincisal opening (MIO)*

an indicator for success (**Table 4**).

Modifications of this technique have been introduced, with the use of mini suture anchors screwed into the condyle, in the hope of achieving better long-term fixation and stability of the reduced disc. A variety of orthopaedic suture anchors have been used for this purpose, most commonly the Mitek [29] and Arthrex mini-anchors [15], however alternatives have also demonstrated success, such as one study that reports the use of orthodontic mini-screws [24]. Such techniques aim to offer a predictable long-term result, however, may not be most appropriate where it is difficult to insert a screw into the condyle, such as in the small, resorbed

Arthroscopic repositioning of the disc and suturing provides an alternative to procedures involving an open incision. Arthroscopy is a more minimally invasive approach, permitting the selective operation on articular disc without causing damage to the other tissues of the TMJ, as well as reducing risk of iatrogenic facial nerve injury which can be associated with open surgery (arthrotomy). Surgically, this involves the creation of three portals, one for the arthroscope and two for instrumentation permitting the passing of a suture through the disc. This technique, despite its conservative nature, is mainly limited by its technical difficulty, and is best performed by an experienced surgeon to ensure a long-term stable outcome [16, 17, 32]. One article also reported the use of a modified meniscopexy technique, whereby a splint was used by patients for a period before surgery, opening the joint space. An anterior-repositioning splint was during the surgical procedure to place the mandible into an ideal relationship with the maxilla. The disc is finally repositioned and sutured anteriorly and laterally to the capsular ligament using an open preauricular approach. Patients then wear the splint postoperatively which is gradually made smaller and narrower, slowly reducing the joint space to its normal anatomical size with the aim of reducing displacement or relapse of the disc repositioning [22].

Several outcome variables were used as measures post-surgery. These included maximal interincisal opening (MIO), post-operative pain using the visual analogue scale (VAS) or questionnaire, changes in diet consistency, mandibular range of motion, joint clicking (including other noises), the use of medications, joint loading

MIO is the measurement of the distance between the incisal edges of maxillary central incisors to mandibular central incisors at maximum mouth opening. During anterior disc displacement, mandibular opening becomes limited, thus corrective meniscopexy should increase mouth opening in successful cases allowing MIO to be

When comparing the different techniques used in the studies, the greatest increase in mean MIO was seen for patients who had undergone arthrotomy using Mitek mini-anchors compared to arthroscopic techniques [17, 18, 21, 26, 28]. However, it should be noted that the severity of TMD within the patient cohorts is likely to differ, with higher Wilkes' classifications having further disc degeneration and thus limited mouth opening. Further to this, cohort size has implications on reliability of the results, with smaller cohorts being less reliable to compare surgical techniques based on outcomes. Rajkumar et al. found that MIO increased most significantly, in patients with disc displacement without reduction (DDwoR), within the first month after surgery, with significantly smaller increases seen up to 6 months post-operatively. Although it is difficult to compare between these studies

signs, MRI to evaluate disc position, disc rupture, and muscular pain.

**108**

*Pre-operative and post-operative mouth opening.*

due to differing techniques used and other difference in key variables, similar trends can be seen from the values provided, highlighting the importance of correct disc position in mechanical action of the mandible.

#### *3.3.2 Pain*

Pain can be used as a subjective measure of surgical outcomes. Within the studies we looked at, there were three methods of measuring pain: using a questionnaire to give a pain score out of 10, using the Visual Analogue Scale (VAS) or by reporting the percentage of patients with pain pre and post operatively. These have been summarised in the table as average values within the patient cohorts (**Table 5**).

Overall, all studies showed an improvement in pain scores on follow up. The VAS was the most commonly used measure of quantifying pain improvement post-operatively. This can be said to be due to its relative simplicity and quantitative nature. However, there has been debate with regards to its validity. Patients may report pain with a certain degree of bias and also may not be able to report pain relief reliably owing to difficulties in recalling previous pain experiences, hence quantitative comparison is challenging [33]. Some studies looked at the simple absence/presence of pain: Ruiz Valero et al. demonstrated a significantly smaller number of patients presenting with painful TMJ symptoms 12 months post-operatively (pre-100%, post-8%). McCain et al. also looked at pain medication use among patients at pre-operative assessment (15/32 patients) and at last visit (6/32) as a secondary


*\* This paper only presented scores for successful surgeries. Visual analogue scale in this paper ranged from 0 to 100 rather than 0 to –10, 0 indicating maximum pain and 100 no pain.*

#### **Table 5.**

*Pre-operative and post-operative pain.*

outcome variable. The subjective nature of pain presents difficulty when data gathering techniques are employed. Furthermore, only two articles measuring pain as an outcome variable in our search followed-up patients for more than 12 months [22, 23]. More studies are needed to look into more long-term data as a measure of success, especially with concerns of patients going on to develop secondary joint diseases in the long-term following disc-repositioning procedures [34]. Also, more sensitive means of pain measurement can be considered to establish pain relief post-operatively, if this is to be used as a primary outcome variable, such as the McGill pain questionnaire [35].

Sheikh et al. investigated pain using a different method. They asked patients about the frequency of pain compared to the severity as a measure of outcomes and found improvements from constant pain to rare and no pain. The table illustrates the distribution of pain frequency pre and post operatively [22] (**Table 6**).

This study looked at the pre and post-operative frequency of pain in 30 patients at a mean of 8.5 years post-op. Although the data illustrates a clear reduction in the frequency of pain within the cohort of patients, it would have been further enhanced by quantitative measures of frequency (e.g. pain occurring between 5 and 10 times per day, etc.). Currently, the interpretation of the terms used to describe pain by patients remains subjective. Further to this, if more data points were collected throughout the post-op period, the course of recovery could be monitored. Nevertheless, frequency of pain remains to be an interesting and useful alternative when measuring pain.

**111**

*Review of Current Practice for Temporomandibular Joint Meniscopexy Surgery*

Constant 66.67 3.33 Moderate 10 6.67 Occasionally 6.67 33.33 Rare 10 33.33 None 6.67 23.33

Arguably this is one of the most important outcomes as a patient's quality of life is greatly determined by this (ability to speak and chew). Goizueta Adame et al. specifically used lateral movements of the mandible as an outcome variable. They found on average in a cohort of 16 patients, the average lateral movement increased

**Frequency of pain Pre-operatively (% of patients) Post-operatively (% of patients)**

Moreover, within the cohort patients looked into by Rajkumar et al., three patients had disc displacement without reduction and their lateral mandibular movements were recorded pre-op and at 6 months post-op. The pre-op average was 1.67 mm increasing to 4.67 mm at 6 months. However, this small patient size cannot be used to determine trends within the data. Further to this, other mandibular movements such as protrusion and retrusion could have been recorded over the long term throughout the studies, in order to create a more complete picture of

Four studies used MRI evaluation post-operatively looking at disc positioning and condylar changes, as a means to qualify the effectiveness of TMJ meniscopexy

Zhang et al. conducted a study with 81 patients with internal derangement of the articular disc, ranging from Wilkes III to V that underwent meniscopexy using bone anchors for fixation. MRI was performed 1–7 days post-operatively to evaluate the position of the disc as poor (none or only reposition in one sagittal plane), good (reposition in two2 sagittal planes) or excellent (reposition in three sagittal planes). They termed a successful outcome as good or better and found that 77 patients were excellent, 1 patient had good outcome and 3 patients had poor outcomes, suggesting

Comparable results are seen in a study of 764 joints treated with an arthroscopic disc repositioning technique, with 729/764 joints deemed as having an excellent outcome [32]. In this particular study however, the specific suture technique was

Such data proves that various techniques can be effectively used to reposition the disc accurately into its anatomic position. However, the efficacy of the techniques described can be attributed to the skill of the operator, and such results may not be reproducible universally. Furthermore, while this data gives a good indication of how well the disc is reduced immediately post-operatively, more information regarding long-term relapse would be useful to determine success. The study also gives no mention of post-operative pain or function. Outcomes that are more important to patients than knowing their disc is in the correct position.

*DOI: http://dx.doi.org/10.5772/intechopen.93403*

**3.4 Mandibular range of motion**

*Pre-operative and post-operative pain distribution.*

**Table 6.**

mandibular function [24].

procedures.

from 3.9 mm pre-op to 10.3 mm post-op [17].

**3.5 Evaluation of disc position using MRI post-operatively**

a 96.3% success rate using bone anchors in arthrotomy [27].

not described, making comparison difficult.

*Review of Current Practice for Temporomandibular Joint Meniscopexy Surgery DOI: http://dx.doi.org/10.5772/intechopen.93403*


**Table 6.**

*Oral and Maxillofacial Surgery*

**Study Surgical technique No. of** 

Meniscopexy

with Mitek anchors

Meniscopexy

Meniscopexy using posterior double pass suture

using Suture

with Mitek anchors

with orthodontic anchors

Abramowicz et al. [23] Not specified 18 9/10 1.3/10 20 years

McCain et al. [18] Arthroscopic suture

Ruiz Valero et al. [28] Open Meniscopexy

Sheikh et al. [22] Splint assisted

Goizueta Adame et al. [17] Arthroscopic

Sharma et al. [19] Open Meniscopexy

Göçmen et al. [26] Open Meniscopexy

Rajkumar et al. [24] Open Meniscopexy

*rather than 0 to –10, 0 indicating maximum pain and 100 no pain.*

**patients in cohort** **Pre-op pain**

32 VAS score for joint function\* 41.9

50 100% of patients

30 See

16 VAS score 7.6

10 Not

7 VAS Score 7.9

10 Not

separate table below

specified

specified

**Post-op pain**

VAS score for joint function\* 71.5

8% of patients

See Separate table below

> VAS score 0.9

100% "Pain relief"

> VAS score 0.6

**Follow-up period (time post-op)**

Not specified

12 months

8.5 years

12 months

12 months

12 months

3.5 6 months

outcome variable. The subjective nature of pain presents difficulty when data gathering techniques are employed. Furthermore, only two articles measuring pain as an outcome variable in our search followed-up patients for more than 12 months [22, 23]. More studies are needed to look into more long-term data as a measure of success, especially with concerns of patients going on to develop secondary joint diseases in the long-term following disc-repositioning procedures [34]. Also, more sensitive means of pain measurement can be considered to establish pain relief post-operatively, if this is to be used as a primary outcome variable, such as the

*This paper only presented scores for successful surgeries. Visual analogue scale in this paper ranged from 0 to 100* 

Sheikh et al. investigated pain using a different method. They asked patients about the frequency of pain compared to the severity as a measure of outcomes and found improvements from constant pain to rare and no pain. The table illustrates the distribution of pain frequency pre and post operatively [22] (**Table 6**).

This study looked at the pre and post-operative frequency of pain in 30 patients at a mean of 8.5 years post-op. Although the data illustrates a clear reduction in the frequency of pain within the cohort of patients, it would have been further enhanced by quantitative measures of frequency (e.g. pain occurring between 5 and 10 times per day, etc.). Currently, the interpretation of the terms used to describe pain by patients remains subjective. Further to this, if more data points were collected throughout the post-op period, the course of recovery could be monitored. Nevertheless, frequency of pain remains to be an interesting and useful alternative when measuring pain.

**110**

*\**

**Table 5.**

McGill pain questionnaire [35].

*Pre-operative and post-operative pain.*

*Pre-operative and post-operative pain distribution.*

#### **3.4 Mandibular range of motion**

Arguably this is one of the most important outcomes as a patient's quality of life is greatly determined by this (ability to speak and chew). Goizueta Adame et al. specifically used lateral movements of the mandible as an outcome variable. They found on average in a cohort of 16 patients, the average lateral movement increased from 3.9 mm pre-op to 10.3 mm post-op [17].

Moreover, within the cohort patients looked into by Rajkumar et al., three patients had disc displacement without reduction and their lateral mandibular movements were recorded pre-op and at 6 months post-op. The pre-op average was 1.67 mm increasing to 4.67 mm at 6 months. However, this small patient size cannot be used to determine trends within the data. Further to this, other mandibular movements such as protrusion and retrusion could have been recorded over the long term throughout the studies, in order to create a more complete picture of mandibular function [24].

#### **3.5 Evaluation of disc position using MRI post-operatively**

Four studies used MRI evaluation post-operatively looking at disc positioning and condylar changes, as a means to qualify the effectiveness of TMJ meniscopexy procedures.

Zhang et al. conducted a study with 81 patients with internal derangement of the articular disc, ranging from Wilkes III to V that underwent meniscopexy using bone anchors for fixation. MRI was performed 1–7 days post-operatively to evaluate the position of the disc as poor (none or only reposition in one sagittal plane), good (reposition in two2 sagittal planes) or excellent (reposition in three sagittal planes). They termed a successful outcome as good or better and found that 77 patients were excellent, 1 patient had good outcome and 3 patients had poor outcomes, suggesting a 96.3% success rate using bone anchors in arthrotomy [27].

Comparable results are seen in a study of 764 joints treated with an arthroscopic disc repositioning technique, with 729/764 joints deemed as having an excellent outcome [32]. In this particular study however, the specific suture technique was not described, making comparison difficult.

Such data proves that various techniques can be effectively used to reposition the disc accurately into its anatomic position. However, the efficacy of the techniques described can be attributed to the skill of the operator, and such results may not be reproducible universally. Furthermore, while this data gives a good indication of how well the disc is reduced immediately post-operatively, more information regarding long-term relapse would be useful to determine success. The study also gives no mention of post-operative pain or function. Outcomes that are more important to patients than knowing their disc is in the correct position.

Rajkumar et al. conducted MRI assessment at 6 months for 10 patients managed with meniscopexy with orthodontic mini-screws, finding stable positioning of the disc and lack of progression of arthritic changes of the condyle on evaluation [24]. Zhou et al. when using MRI scans to follow up patients post-operatively found 4.7% of patients relapsed with anterior disc displacement. Of the 149 patients, 5 relapsed after 1 year and 2 after 2 years [25]. However, further studies investigating the longterm follow up of all cases is required to accurately ascertain incidence of relapse.

Other outcomes such as reduction in joint noises, increase in diet consistency, muscle pain and joint loading signs were also looked at in a few isolated studies as a means to assess the success of surgery. However, there were not enough studies available to effectively use these to determine outcomes.
