Subscapularis tears: hidden and forgotten no more

Editorial Commentary: Subtle Degenerative Tears That So Commonly Involve the Upper Third of the Subscapularis Are Oftentimes Missed

Subtle degenerative tears that so commonly involve the upper third of the subscapularis are oftentimes missed. However, there are physical examination, imaging, and arthroscopic findings that are highly suggestive of subscapularis tearing. Positive belly-press and bear hug tests, a thinner and longer subscapularis tendon, subscapularis muscle, belly loss of bulk or fatty infiltration, narrow coracohumeral distance, and biceps pathology are indicative. Artificial intelligence-based predictive algorithms can estimate the likelihood of subscapularis tearing based on a combined analysis of these and other features. Improved outcomes should logically be expected for those shoulders with subscapularis tears that are identified and repaired. Finally, some research suggests that debridement remains an alternative to repair; however, pending future research, debridement is not the author's preferred treatment.

Higher Upper Subscapularis Goutallier Grade and Coracohumeral Distance Narrowing Are Predictive of Subscapularis Tears in Patients Undergoing Arthroscopic Rotator Cuff Repair

PURPOSE

To evaluate the relation between subscapularis (SSC) Goutallier grade or coracohumeral distance (CHD) and SSC tears, as well as the relation between these radiographic variables and long head of the biceps tendon lesions.

METHODS

A retrospective analysis was conducted on prospectively maintained data on patients who underwent arthroscopic rotator cuff repair of SSC tears between 2011 and 2021 with at least 6 months of follow-up. Patients with identified subscapularis tears during arthroscopy were included. A control group was established by randomly selecting patients without SSC tears from the same study period. Goutallier grading and CHD were obtained from preoperative magnetic resonance imaging (MRI) scans. Receiver operating characteristic analysis was conducted to define optimal cutoff values for these diagnostic measures.

RESULTS

The study included 735 patients with SSC tears and 249 patients in the control group. Comparing subscapularis tear and intact groups' Goutallier grades revealed significant differences in infraspinatus, upper and lower SSC, and overall SSC (P < .001). No significant difference was detected in supraspinatus Goutallier grade (P = .364). An SSC tear was observed in 58.3% (n = 265) of patients with Goutallier grade 0 of the upper SSC, 77.1% (n = 195) of patients with grade 1 changes, 98.7% (n = 155) with grade 2 changes, and 100% of grade 3 or 4 changes. Goutallier grade of the upper SSC showed a significant correlation with tear size (rs = 0.533; P < .01). CHD measurements were lower in individuals with SSC tears compared to those without tears (6.6 ± 1.7 vs 9.6 ± 1.8; P < .001). Upper SSC Goutallier grade >1 had an acceptable area under the curve (AUC) of 0.742. CHD of 7.96 mm or less had an excellent predictive AUC of 0.879.

CONCLUSIONS

Higher Goutallier grade and CHD narrowing are potential associations predictive of SSC tears. Routine MRI assessment of muscle of the upper SSC and the CHD can contribute to the diagnostic accuracy of SSC tears and offer valuable information regarding the severity of such tears.

LEVEL OF EVIDENCE

Level III, diagnostic study.

Magnetic resonance imaging based coracoid process morphology and its associations with isolated subscapularis tendon tears in Chinese patients

OBJECTIVES

This study aims to assess the association between isolated subscapularis tears and coracoid morphology using magnetic resonance imaging (MRI) and to calculate the optimal cut-off values of the significant predictor to predict subscapularis tears.

PATIENTS AND METHODS

Between January 2018 and December 2022, a total of 60 patients (29 males, 31 females; mean age: 58.4±8.4 years; range, 18 to 80 years) diagnosed with subscapularis tendon tears who were treated as Group A and 60 patients (29 males, 31 females; mean age: 46.8±11.5 years; range, 18 to 80 years) without subscapularis tendon tears who were treated as Group B were included. Axial coracoid-humeral distance (aCHD), sagittal coracoid-humeral distance (sCHD), coracoid overlap (CO) and coracoid angle (CA) of all patients were measured. Logistic regression was used to investigate the association between subscapularis tears as variables including aCHD, sCHD, CO and CA. Receiver operating characteristic curve analysis was used to determine the diagnostic values of coracoid morphology for subscapularis tears.

RESULTS

The mean values of CO, aCHD and sCHD in Group A were 22.16 mm, 5.13 mm, and 5.56 mm, respectively. The mean values in Group B were 16.99 mm, 7.18 mm, and 7.29 mm, respectively. The degree of CA in Group A was 95.81 and 111.69 in Group B. The differences in the above measurement values were significant between two Groups. The CO was found to be associated with higher odds of subscapularis tears. The optimal cut-off value of CO was 19.79 mm.

CONCLUSION

Based on our study results, CO is positively associated with isolated subscapularis tears. In addition, coracoid bursa effusion, cysts in the lesser tuberosity or a tear and malposition of long head of the biceps tendon on MRI may predict the presence of a clinically significant subscapularis tear.

Editorial Commentary: Artificial Intelligence Models Using Machine Learning Can Improve Preoperative Identification of Subscapularis Pathology

Subscapularis pathology is difficult to diagnose, in part because of decreased sensitivity and accuracy in identifying tears with magnetic resonance imaging (MRI) when compared to other cuff tendons. Artificial intelligence evaluation of patient physical examination and MRI data using a machine learning model shows that arthroscopically confirmed partial- or full-thickness subscapularis tears are highly associated with abnormal subscapularis tendon length, long head of the biceps tears, and subscapularis fatty atrophy, and on physical examination, with weakness with internal rotation and positive lift-off, belly press, and bear hug tests. Today, physicians may use machine learning as a tool, but this model may not currently be sufficient to drastically change practice. However, with continued research and development, which is occurring rapidly, similar models could aid physicians in timely identification of pathology and optimization of preoperative planning, as well as physician training and education.

Arthroscopic Modified Subacromial Viewing Portal Repair of Upper Third of Subscapularis Tendon Partial-Thickness Tears

At present, the repair pattern of upper third of subscapularis tendon partial-thickness tears (upper-third tendon tears) is performed in the glenohumeral joint and conventional subacromial viewing portal, but the visualization of subscapularis tendon and footprint is poor when using a 30° scope. The modified subacromial viewing portal presented in this Technical Note is a modified surgical technique for the repair of upper-third tendon tears. Since the scope forms an angle of 70° with the subscapularis tendon and footprint of lesser tuberosity, satisfactory visualization can be obtained when using 30° scope; the predesigned surgical portal and working space without bony barrier can offer a smooth surgical procedure. Our surgical technique is described in pearls, pitfalls, advantages, and disadvantages.

A Machine Learning Model Demonstrates Excellent Performance in Predicting Subscapularis Tears Based on Pre-Operative Imaging Parameters Alone

PURPOSE

To develop a machine learning model capable of identifying subscapularis tears before surgery based on imaging and physical examination findings.

METHODS

Between 2010 and 2020, 202 consecutive shoulders underwent arthroscopic rotator cuff repair by a single surgeon. Patient demographics, physical examination findings (including range of motion, weakness with internal rotation, lift/push-off test, belly press test, and bear hug test), and imaging (including direct and indirect signs of tearing, biceps status, fatty atrophy, cystic changes, and other similar findings) were included for model creation.

RESULTS

Sixty percent of the shoulders had partial or full thickness tears of the subscapularis verified during surgery (83% of these were upper third). Using only preoperative imaging-related parameters, the XGBoost model demonstrated excellent performance at predicting subscapularis tears (c-statistic, 0.84; accuracy, 0.85; F1 score, 0.87). The top 5 features included direct signs related to the presence of tearing as evidenced on magnetic resonance imaging (MRI) (changes in tendon morphology and signal), as well as the quality of the MRI and biceps pathology.

CONCLUSIONS

In this study, machine learning was successful in predicting subscapularis tears by MRI alone in 85% of patients, and this accuracy did not decrease by isolating the model to the top features. The top five features included direct signs related to the presence of tearing as evidenced on MRI (changes in tendon morphology and signal), as well as the quality of the MRI and biceps pathology. Last, in advanced modeling, the addition of physical examination or patient characteristics did not make a significant difference in the predictive ability of this model.

LEVEL OF EVIDENCE

Level III, diagnostic case-control study.

Management of irreparable subscapularis tears: Current concepts

Primary repair of acute subscapularis (SSC) tears provides excellent results, but tendon retraction, muscle atrophy, fatty infiltration, and humeral head migration may render a more chronic tear irreparable. These irreparable SSC tears present a diagnostic and treatment challenge for orthopaedic surgeons. Careful physical examination and imaging evaluation can help to distinguish those with reparable versus irreparable tears, but they are still not very reliable due to the methodological limitations of current evidence. Therefore, future research using 3D and quantitative measurement techniques is necessary to better predict the irreparability of the SSC. When conservative treatment of an irreparable SSC tear fails, reversed shoulder arthroplasty has been established as the preferred treatment option for older, low-demand patients with arthropathy, providing reliable improvements in pain and function. In younger patients without significant arthropathy, musculotendinous transfers are the treatment of choice. The pectoralis major transfer is historically the most frequently performed procedure and provides improved range of motion and pain relief, but fails to adequately restore strength and shoulder function. The latissimus dorsi transfer has gained increased interest over the last few years due to its biomechanical superiority, and early clinical studies suggest improved outcomes as well. More recently, anterior capsular reconstruction has been proposed as an alternative to musculotendinous transfers, but clinical data are completely lacking. Future high-quality randomised controlled trials are necessary to reliably compare the different musculotendinous transfers and anterior capsular reconstruction.

[Short-term effectiveness of arthroscopic repair via modified subacromial viewing portal in treatment of Lafosse subscapularis tendon tears]

Objective

To investigate short-term effectiveness of arthroscopic repair via modified subacromial viewing portal (hereinafter referred to as modified viewing portal) in treatment of LafosseⅠsubscapularis tendon tears.

Methods

A clinical data of 52 patients with LafosseⅠsubscapularis tendon tears, who underwent the arthroscopic repair via modified viewing portal between October 2020 and November 2022 and met the selective criteria, was retrospectively analyzed. There were 15 males and 37 females with an average age of 63.4 years (range, 41-76 years). Twelve patients had trauma history and the other 40 patients had no obvious inducement. The main clinical symptom was shoulder pain and the hug resistance tests were positive in all patients. The interval between symptom onset and admission ranged from 3 to 26 months (mean, 7.2 months). The shoulder pain and function were evaluated by visual analogue scale (VAS) score, American Shoulder and Elbow Surgeons (ASES) score, and University of California Los Angeles (UCLA) score before operation and at 12 months after operation. The shoulder range of motion (ROM) of forward flexion, abduction, and external rotation and the internal rotation strength were measured before operation and at 3 and 12 months after operation. MRI was performed at 3-6 months after operation to assess the tendon healing and the structural integrity and tension of reattached tendon. Patient's satisfactions were calculated at last follow-up.

Results

All incisions healed by first intention, no complication such as incision infection or nerve injury occurred. All patients were followed up 12-37 months (mean, 18.5 months). The VAS, UCLA, and ASES scores at 12 months after operation significantly improved when compared with those before operation ( P<0.05). The ROMs of abduction and forward flexion and the internal rotation strength at 3 and 12 months significantly improved when compared with those before operation ( P<0.05); and the ROMs at 12 months significantly improved compared to that at 3 months ( P<0.05). However, there was no significant difference ( P>0.05) in the ROM of external rotation at 3 months compared to that before operation; but the ROM at 12 months significantly improved compared to that before operation and at 3 months after operation ( P<0.05). Thirty-one patients underwent MRI at 3-6 months, of which 28 patients possessed intact structural integrity, good tendon tension and tendon healing; 3 patients underwent tendon re-tear. At last follow-up, 41 patients (78.8%) were very satisfied with the effectiveness, 7 were satisfied (13.5%), and 4 were dissatisfied (7.7%).

Conclusion

Arthroscopic repair via modified viewing portal for Lafosse Ⅰsubscapularis tendon tears, which can achieve the satisfactory visualization and working space, can obtain good short-term effectiveness with low overall re-tear risk.

Subscapularis tendon tear detection using axial internal rotation MRI: semiquantitative and quantitative analysis

Background

Magnetic resonance image (MRI) of the subscapularis tendon plays an important role in preoperative planning. This retrospective study aimed to evaluate the diagnostic value and quantitative measurement of an additional internal rotation sequence in the detection of partial subscapularis tendon tears.

Methods

The study included 76 patients who underwent arthroscopy and magnetic resonance (MR) shoulder between January 2018 to December 2019. Three different sets of images were evaluated in each case to determine the diagnostic value in the detection of partial subscapularis tendon tears including Set 1: standard axial fat-suppressed proton density (PD/FS) image and sagittal fat-suppressed T2 weight image (T2W/FS) images, Set 2: standard axial PD/FS and internal rotation PD/FS images, and Set 3: standard axial PD/FS, sagittal T2W/FS and axial internal rotation PD/FS images. Subscapularis tendon tear was diagnosed by arthroscopy and patients with or without tears were grouped. The coracohumoral distance (CHD), coracoglenoid angle (CGA), coracohumeral angle (CHA), CHD difference and CHD ratio were evaluated and compared between groups using univariate and multivariate analysis. The interreader agreement was assessed. The cut-off point for the prediction of subscapularis tears was calculated.

Results

Twenty-nine shoulders revealed partial subscapularis tendon tears (29/76, 38.2%). Imaging Set 3 provided the highest sensitivity and accuracy {79-83% [confidence interval (CI): 0.60-0.95], 75-76% (CI: 0.63-0.85)}, compared to image Set 2 [31-58% (CI: 0.15-0.76), 67-68% (CI: 0.55-0.79)] and Set 1 [17-21% (CI: 0.06-0.40], 61-66% (CI: 0.54-0.76)], and a moderate level of interobserver agreement (Kappa =0.55). Axial CHD [odd ratio (OR) =1.48, P=0.044], internal rotate CHD (OR =0.68, P=0.02), CHD difference (OR =2.58, P<0.001), and CHD ratio (OR =1.34, P<0.001) were associated with subscapularis tears. A CHD difference and CHD ratio of more than 0.04 mm and 1.01 achieved a 90% sensitivity and 72% specificity, both.

Conclusions

Internal rotation during MRI can increase diagnostic accuracy for subscapularis tendon partial tears. The CHD differences and CHD ratio are useful parameters to indicate subscapularis tears. This technique may improve preoperative management and reduce the consequences of delayed diagnosis and treatment.

Rotator Cuff Repair with Knotless All-Suture Medial Row Anchors and Biceps Autograft Augmentation

Incomplete healing and/or functional failure following rotator cuff tear repair remains a challenging problem for both patients and surgeons. Augmentation strategies are growing to increase healing through biologic and mechanical mechanisms to improve functional results after arthroscopic rotator cuff repair. The majority of currently described augmentation techniques use allograft tissue. An alternative, low-cost, autograft option for augmentation is the use of the long head of biceps tendon autograft as a free functional graft. Here, we describe the use of autograft biceps tendon as a viable option for augmentation of double-row rotator cuff repair with knotless all-suture suture anchors.

Arthroscopic Subscapularis Repair With Preserved Biceps Anatomy

Arthroscopic subscapularis repair continues to improve with the advancement of surgical technique and critical focus on careful intraoperative evaluation. As identification of these tears increases, there is an expected increase in repair rates as well. Anatomically, the upper border of the subscapularis and the long head of the biceps (LHB) tendon are in close relation. Many surgeons have advocated concomitant LHB tenotomy versus tenodesis in conjunction with operative subscapularis tears. We hypothesized that in the setting of a preserved anatomic biceps pulley and no LHB pathology, isolated subscapularis repair would result in excellent clinical outcomes when compared with subscapularis repair and biceps tenotomy or tenodesis.

Current Understanding and New Advances in the Surgical Management of Reparable Rotator Cuff Tears: A Scoping Review

Rotator cuff (RC) tears are among the most common musculoskeletal disorders and can be associated with pain, weakness, and shoulder dysfunction. In recent years, there have been significant advances with regard to the understanding of rotator cuff disease and its management. With technological improvements and advanced diagnostic modalities, there has been much progress as to improved understanding of the pathology. Similarly, with advanced implant designs and instrumentation, operative techniques have evolved. Furthermore, refinements in postoperative rehabilitation protocols have improved patient outcomes. In this scoping review, we aim to provide an overview of the current knowledge on the treatment of rotator cuff disorders and to highlight recent advances in its management.

Can subcoracoid effusion be a more specific finding for subscapularis tear among rotator cuff pathologies on magnetic resonance imaging?

HYPOTHESIS AND BACKGROUND

Magnetic resonance imaging (MRI) is a well-known, noninvasive diagnostic method for rotator cuff tendon pathologies that are not very sensitive for subscapularis tendon tears. Subcoracoid effusion (SE) is an easily recognizable radiologic sign on MRI. In this study, we aimed to examine the relationship of SE with rotator cuff tear and to investigate whether SE could be a supportive finding in the diagnosis of subscapularis tear in preoperative MRI. Our hypothesis was that SE was a more specific finding of subscapularis tear than other rotator cuff tears.

METHODS

The data of patients who underwent shoulder arthroscopy in our clinic between 2017 and 2021 were analyzed retrospectively. Four groups were included in the study: patients with a rotator cuff tear accompanied by a subscapularis tear (group 1, n = 273), patients with isolated subscapularis tear (group 2, n = 57), patients with rotator cuff tear with intact subscapularis tendon (group 3, n = 190), and patients without any rotator cuff pathology (group 4, n = 263). Arthroscopic video records and MRIs of all patients were evaluated retrospectively. Subscapularis tendon tears were classified according to the Lafosse classification.

RESULTS

There was a statistically significant difference between the groups in terms of the presence of SE on MRI (P = .001). The presence of SE in group 1 and group 2 was statistically significantly higher than that in both group 3 and group 4 (P = .001), and there was no significant difference between group 3 and group 4 (P > .05). A significant relationship was found between Lafosse classification and SE (P = .001). When the diagnostic powers of the detection of SSC tear and the presence of SE on MRI for SSC tear were compared, Kappa values were 0.615 (P = .001) and 0.701 (P = .001), and overall diagnostic accuracy rates were 80.3% and 85.5%, respectively.

CONCLUSION

We conclude that SE is a more specific finding for subscapularis tears than other rotator cuff pathologies. We suggest that SE on MRI should also be considered in patients with a rotator cuff tear in whom a subscapularis tear was not detected in preoperative MRI and that the subscapularis tendon should be carefully evaluated during surgery in cases where the effusion is positive.

Subscapularis tendon tears hidden by the medial biceps sling can be missed on arthroscopic examination

INTRODUCTION

To investigate (1) the prevalence of "hidden lesions" and "non-hidden lesions" of subscapularis tendon tears requiring repair during arthroscopic examination that would be missed by a 30° arthroscope, but could be identified by a 70° arthroscope, from the standard posterior portal and (2) the correlation of preoperative internal rotation weakness and findings of magnetic resonance imaging (MRI) indicating hidden lesions.

MATERIALS AND METHODS

We retrospectively examined 430 patients who underwent arthroscopic subscapularis repair between was initially nonvisible with a 30° arthroscope but became visible only with a 70° arthroscope from the standard posterior portal. The preoperative and intraoperative findings of the hidden lesion group (n = 82) were compared with those of the non-hidden lesion group (n = 348). 2016 and 2020. A hidden lesion was defined as a subscapularis tendon tear requiring repair that preoperative internal rotation weakness was assessed using the modified belly-press test. Preoperative MR images were reviewed using a systemic approach.

RESULTS

The prevalence of hidden lesions was 19.1% (82/430). No significant difference was found in preoperative internal rotation weakness between the groups. Preoperative MRI showed a significantly lower detection rate in the hidden lesion group than in the non-hidden group (69.5% vs. 84.8%; P = 0.001). The hidden lesions were at a significantly earlier stage of subscapularis tendon tears than the non-hidden lesions, as revealed by the arthroscopic findings (Lafosse classification, degree of retraction; P = 0.003 for both) and MR findings (muscle atrophy, fatty infiltration; P = 0.001, P = 0.005, respectively).

CONCLUSIONS

Among the subscapularis tears requiring repair, 19.1% could be identified by a 70° arthroscope, but not by a 30° arthroscope, through the posterior portal. The hidden lesions showed a significantly lower detection rate on preoperative MRI than the non-hidden lesions. Thus, for subscapularis tears suspected on preoperative physical examination, the 70° arthroscope would be helpful to avoid a misdiagnosis.

Quantitative MRI indicators and features for partial subscapularis tendon tears on conventional shoulder MRI

Background

Diagnosing partial subscapularis (SSC) tendon tears still faces challenges. A failure rate of massive posterosuperior rotator cuff tear repair will be highly increased when extending more than one-third of SSC tendon. This study aims to investigate the quantitative indicators and features of partial SSC tears on conventional shoulder MRI and improve the preoperative diagnostic accuracy.

Materials and methods

Four hundred and thirty-seven patients underwent MRI and arthroscopy were retrospectively reviewed; 89 patients with partial SSC tears in case group and 50 patients with normal SSC in control group were included. Six MRI features with the explicit definition of some quantitative indicators were evaluated.

Results

Fissure sign showed the highest diagnostic efficiency for the partial SSC tears, with a specificity of 92%, sensitivity of 75.3%, and accuracy of 81.3%. Thinning of SSC, fluid collection under the coraco-glenoid arch (CGA), and combined SSP complete tear also showed high specificity of 86%, 80%, and 80%, respectively, while the sensitivity and accuracy were moderate, with a sensitivity of 38.2%, 50.6%, and 48.3%, respectively, an accuracy of 55.4%, 61.2%, and 59.7%, respectively. The specificity, sensitivity, and accuracy of lesser tuberosity cysts were all moderate with values of 68%, 56.2%, and 60%, respectively. However, fat accumulation under the CGA showed no significant difference between the partial SSC tears group and the control group.

Conclusion

Several specific MRI features with quantitative indicators defined in this study can be used to improve the accuracy of preoperative MRI diagnosis of partial SSC tears.

Transosseous repair with a cortical implant for greater tubercle cyst-related rotator cuff tear results in good clinical outcomes, but significant implant migration

PURPOSE

To evaluate whether an arthroscopic transosseous technique (ATO) with cortical implants is effective for rotator cuff tear (RCT) repair in patients with cysts of the greater tuberosity (GTC).

METHODS

Patients treated with the ATO technique between January 2013 and October 2017 were evaluated. Inclusion criteria were patients treated for both cyst-related and non-cyst-related RCTs and patients with a moderate-sized tear (1-3 cm) according to the DeOrio and Cofield classification. A total of 39 patients were separated into two groups: Group 1 (n = 16) patients with cyst-associated RCT, and Group 2 (n = 23) patients with no cyst. Implant pull-out and migration were evaluated radiologically on standard antero-posterior shoulder radiographs and rotator cuff re-tear was assessed on magnetic resonance images at the final follow-up examination. Group 1 patients were separated into two subgroups according to cyst size (cyst < 5 mm and cyst ≥ 5 mm) and subgroup analysis was performed. Clinical assessment was performed using a visual analog scale, the Constant score and Oxford shoulder score.

RESULTS

The mean follow-up time was 33.7 ± 11.7 months. The mean cyst size was 5.4 ± 1.5 mm. There was no significant difference in re-tear rates between the cystic and non-cystic groups. The mean implant migration distance was 3.0 ± 2.2 mm in patients with a RCT -related cyst and 0.7 ± 0.8 mm in those without a cyst. A statistically significant difference was found between the groups (p = 0.002). There was no statistically significant difference between the groups in respect of clinical scores. No implant failure was observed.

CONCLUSION

The ATO method performed with a cortical implant in RCTs resulted in satisfactory recovery and clinical outcomes in the short to medium term with low failure rates. While no implant failures were observed, implant migration was associated with cyst presence. Therefore, judicious use is advocated in the choice of transosseous fixation for cyst-related RCTs and patients should be informed of the possibility of implant migration.

LEVEL OF EVIDENCE

III.

Comparison of Open Versus Arthroscopic Repair for Subscapularis Tendon Tears With or Without Concomitant Supraspinatus Tendon Tears

Background:

The literature comparing open and arthroscopic repair of subscapularis tendon (ST) tears is insufficient.

Purpose:

To compare the clinical results of open versus arthroscopic repair of ST tears with or without concomitant supraspinatus tears.

Study Design:

Retrospective cohort study.

Methods:

We retrospectively evaluated 70 patients treated for isolated ST tears and ST tears with concomitant supraspinatus tendon tears at a single center between 2011 and 2019. Patients were divided into 2 groups: those who underwent open ST repairs (group O) and those with an arthroscopic ST repair (group A). Range of motion (ROM), liftoff and belly-press tests, and Constant-Murley (CM) scores were included in the pre- and postoperative functional evaluations. The minimal clinically important difference was calculated using the anchor-based method for changes in CM score. Tear size was evaluated according to the Lafosse classification. The categorical data were assessed using the Pearson chi-square, Fisher exact, and Fisher-Freeman-Halton tests. The parametric and nonparametric data were evaluated using the Student t test and Mann-Whitney U test, respectively. The dependent groups (for nonnormally distributed data) were evaluated using the Wilcoxon signed rank test.

Results:

Group O included 34 patients, and group A included 36 patients. The mean age was 62.9 years, and the mean follow-up period was 66.7 months. Even though group O exhibited a significantly better preoperative CM score (53.7 ± 4.6 vs 48.9 ± 6.8 [mean ± SD]; P = .001), group A had a significantly better postoperative CM score (88.7 ± 4.7 vs 84.6 ± 2.9; P < .001). Our measurements revealed a minimal clinically important difference of 11.5 points for the CM score. Group A had significantly greater postoperative ROM in abduction (153° vs 143.9°; P = .005) and forward elevation (159.1° vs 149.7°; P = .005), as well as significantly greater postoperative improvement in positive belly-press test results (P = .028). Complications occurred in 4 patients in group O and in 1 patient in group A.

Conclusion:

The study findings indicated that arthroscopic ST repair was more advantageous than open repair in terms of ROM and functional outcomes.

[Treatment of subscapularis tendon lesions]

The further development of minimally invasive techniques in recent years, enables adequate intraoperative visualization, mobilization and stable reconstruction even of larger subscapularis tears resulting in good to excellent clinical and structural results. Chronic tears of the subscapularis tendon with high grade muscle atrophy and advanced fatty infiltration can be treated with a muscle tendon transfer (e.g. pectoralis major or latissimus dorsi transfer). If pseudoparalysis and/or signs of anterosuperior decentration of the humeral head or defect arthropathy are present, in most cases a reverse shoulder arthroplasty represents the only surgical option.

[Anatomy and diagnostics of subscapularis tendon lesions]

Among lesions of the rotator cuff, subscapularis tendon tears are one of the less common injuries and mostly occur in combination with additional lesions of the posterosuperior rotator cuff and the long biceps tendon. If a subscapularis tendon rupture is suspected in the initial clinical testing, the primary diagnostics should include modern cross-sectional magnetic resonance imaging to assess the tendon lesion and to detect concomitant pathologies. Nevertheless, subscapularis tendon lesions are often initially overlooked and first correctly diagnosed during shoulder arthroscopy.

Outcome Comparison of Latissimus Dorsi Transfer and Pectoralis Major Transfer for Irreparable Subscapularis Tendon Tear: A Systematic Review

BACKGROUND

Latissimus dorsi transfer (LDT) and pectoralis major transfer (PMT) were developed to treat an irreparable subscapularis tendon tear (ISScT); however, the difference in their outcomes remains unclear.

PURPOSE

To systematically review and compare the outcomes of LDT and PMT for ISScT.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

A systematic review was performed through a comprehensive search of Embase, PubMed, and the Cochrane Library. Studies of LDT or PMT were included according to the inclusion and exclusion criteria. The primary outcome was the Constant-Murley score (CMS) at the final follow-up. Secondary outcomes included the subjective shoulder value (SSV), visual analog scale (VAS) score for pain, active shoulder range of motion, and the belly-press and lift-off tests. Postoperative failure and complication rates were the safety outcome measures. Outcomes were summarized into the LDT and PMT groups, and results were compared statistically (P < .05).

RESULTS

Twelve studies were included in this review: 184 shoulders from 9 studies for the PMT group and 85 shoulders from 3 studies for the LDT group. For the PMT and LDT groups, the mean ages were 58.9 and 55.1 years, respectively, and the mean follow-up was 66.9 and 17.4 months, respectively. Overall, the LDT and PMT groups improved in the primary outcome (CMS) and secondary outcomes (SSV, VAS, ROM, and belly-press and lift-off tests), with low rates of failure and complication. When compared with the PMT group, the LDT group showed more significant improvements in CMS (35.2 vs 24.7; P < .001), active forward flexion (44.3° vs 14.7°; P < .001), abduction (35.0° vs 17.6°; P < .002), and positive belly-press test rate (45% vs 27%; P < .001). No statistically significant difference was seen between the groups in postoperative failure rate, complication rate, mean improvement of active internal rotation, VAS, or SSV.

CONCLUSION

In general, LDT showed significantly better clinical outcomes postoperatively than did PMT. The available fair-quality evidence suggested that LDT might be a better choice for ISScT. Further evaluations on the relative benefits of the 2 surgical approaches are required, with more high-quality randomized controlled studies.

Current concepts review in the management of subscapularis tears

Subscapularis (SSc) is the prime internal rotator of shoulder. It is the most powerful rotator cuff muscle, maintaining the anterior force couple of shoulder. The tears in SSc as any other rotator cuff muscles might result from a traumatic event or more commonly from intrinsic degeneration. With the advent and widespread use of shoulder arthroscopy, SSc tears, which were once considered as "forgotten or hidden lesions" are now being increasingly recognized. Isolated SSc tears are relatively rare. They occur in combinations. Clinically internal rotation can be near normal because of the compensation provided by other internal rotators. It is not uncommon for patients with SSc tear to be normal on routine physical examination. The Bear Hug test (BHT) has high sensitivity and accuracy in the diagnosis of SSc tear. The combined use of BHT with Belly Press Test has been found optimal for diagnosis. US is an accurate and reliable method for diagnosing SSc tears and outperformed MRI in diagnosing partial-thickness SSc tears. The MRI is currently the most advanced imaging available for diagnosis. The specificity is up to 100%. However, the sensitivity is between 36 and 40%. The earliest classification system for SSc tears was by Fox et al. The commonly used classification is by Lafosse et al. The recent system by Yoo et al. is based on the insertion of SSc. The comma sign is gaining importance not only in arthroscopic diagnosis but also in MRI identification and repair of SSc. The mode of management is mainly arthroscopic. The techniques of repair of SSc are continuously progressing. However, there is no clear consensus on the double vs single-row repairs, biceps tendon management, and the role of coracoplasty. Future research must focus on these areas. Reserve shoulder arthroplasty is reserved for salvage in older age groups. Tendon transfers are performed in young active individuals with irreparable tears.

Association Between Medial Displacement of the Middle Glenohumeral Ligament and Subscapularis Tear Severity

Background:

The intraoperative invisible middle glenohumeral ligament (MGHL) test has been shown to be associated with a subscapularis tendon retraction. However, the preoperative location of the MGHL and its association with subscapularis tear severity has not been evaluated.

Purpose:

To determine (1) the interrater reliability for identification and position of the MGHL, (2) any association between the MGHL position and subscapularis tears, and (3) the cutoff point at which MGHL position can predict subscapularis tear severity.

Study Design:

Cohort study (diagnosis); Level of evidence, 2.

Methods:

The magnetic resonance imaging (MRI) scans and surgical records of 176 patients were retrospectively reviewed by 3 independent orthopaedists. MGHL's identification, level (its position on axial MRI), and medial retraction ratio (distance from the lesser tuberosity to the MGHL divided by the width of the glenoid) were documented, and the interobserver agreement of the 3 indices was assessed. We calculated the association between subscapularis tears and the MGHL level and medial retraction ratio. Receiver operating characteristic (ROC) curve analyses were conducted to establish the optimal threshold of the MGHL medial retraction ratio to predict subscapularis tear.

Results:

The MGHL was identified by at least 2 reviewers in 124 individuals (70.5%). The interobserver reliability was very good for MGHL identification (κ = 0.766), moderate for MGHL level (κ = 0.582), and excellent for MGHL medial retraction ratio (intraclass correlation coefficient = 0.848). A low, positive correlation between MGHL level and subscapularis tear severity was found (Somers d = 0.392, P < .001), as well as a significant association between the medial retraction ratio and Lafosse classification of subscapularis tear size ( P < .001). A medial retraction ratio of ≥1.25 had a sensitivity of 0.70, a specificity of 0.83, and a positive likelihood ratio of 4.20, with excellent accuracy (area under the ROC curve = 0.820) to predict severe subscapularis tear.

Conclusion:

The MGHL was identified in 70.5% of shoulder MRIs. The location of the MGHL on preoperative MRI, as described by its level and the medial retraction ratio, was significantly associated with subscapularis tear severity, and a medial retraction ratio of ≥1.25 was predictive of a severe subscapularis tear.

Postoperative clinical outcomes and radiological healing according to deep and superficial layer detachment in first facet involving subscapularis tendon tear

Background

Subscapularis tendon insertion at the first facet has separate layers (deep and superficial). The purpose of this study is to evaluate postoperative clinical outcomes and radiological healing according to each layer of detachment in the first facet involving subscapularis tendon tear.

Methods

Eighty-three patients who underwent arthroscopic repair due to First facet involving the scapularis tendon tear accompanying small to medium sized posterosuperior cuff tear were classified into three groups (group A: deep layer partial detachment, group B: deep layer complete detachment, but no superficial layer detachment, and group C: deep layer and superficial layer complete detachment). Subscapularis tendon healing was evaluated using computed tomography arthrogram and clinical result was evaluated using American Shoulder and Elbow Surgeons (ASES) shoulder score, Constant score and University of California Los Angeles (UCLA) shoulder score.

Results

Retear rate of the subscapularis tendon was 2.2%, 18.2%, and 33.3% in group A, group B, and group C, respectively. These rates showed statistically significant difference among the three groups, which were classified by deep and superficial layer detachment in the first facet (p=0.003). Group A showed significant difference in subscapularis tendon healing compared with group B and group C (p=0.018 and p<0.001, respectively), but there was no statistical difference between group B and group C (p=0.292). Regarding clinical outcomes, there was no significant difference among three groups in ASES and UCLA score at final follow-up (p=0.070 and p=0.106, respectively).

Conclusions

Complete detachment of deep layer may be related with retear occurrence regardless with detachment of superficial layer, but clinical outcome may not be related with each layer detachment in the first facet involving subscapularis tendon tear.

Diagnostic performance of conventional magnetic resonance imaging for detection and grading of subscapularis tendon tear according to Yoo and Rhee classification system in patients underwent arthroscopic rotator cuff surgery

OBJECTIVES

To assess the diagnostic accuracy of conventional MRI for detecting and grading subscapularis (SSC) tears by applying the Yoo and Rhee classification.

MATERIALS AND METHODS

A total of 179 patients who underwent MRI followed by arthroscopic rotator cuff surgery were enrolled. Two musculoskeletal radiologists evaluated the SSC using axial, oblique sagittal, and oblique coronal MRI according to the Yoo and Rhee classification. Using arthroscopic findings as the reference standard, the sensitivity, specificity, accuracy, and interobserver agreement of SSC tears were analyzed.

RESULTS

Arthroscopy confirmed that the numbers of type I, IIA, IIB, III, IV, and V tears were 35, 70, 35, 9, 9, and 0, respectively. The sensitivity, specificity, and accuracy of readers 1 and 2 for the detection of tears (type IIA or higher) were 85%, 75%, and 82%, and 89%, 70%, and 83%, respectively, while those for the detection of surgical candidates (type IIB or higher) were 77%, 75%, and 75%, and 77%, 83%, and 82%, respectively. The interobserver agreement for detecting SSC tear presence was substantial (κ = 0.70) for reader 1 vs. reader 2, and those for detecting the surgical candidate group was substantial (κ = 0.68) for reader 1 vs. reader 2. The interobserver agreement for grading SSC tears was excellent (κ = 0.86) for reader 1 vs. reader 2.

CONCLUSION

Conventional MRI showed 82.5% and 78.5% average accuracy in detecting IIA and IIB or higher tears by applying the Yoo and Rhee classification for the diagnosis of SSC tears with an excellent interobserver agreement in tear grading.

Literature Review of Subscapularis Tear, Associated injuries, and the Available Treatment Options

The population of Hawai'i is uniquely connected to the Ocean and to open water sports. Shoulder injuries, particularly those to the rotator cuff, are among the most common injuries sustained to athletes participating in ocean sports such as surfing, paddling, and swimming. In addition, rotator cuff injuries increase in prevalence with advanced age. As a consequence, the number of patients in Hawai'i who present with an injury to the subscapularis tendon will continue to rise. However, limited research has been done to delineate the involvement of subscapularis injuries in this population. This article covers the anatomy and function of the subscapularis, the epidemiology and classification of tears in this tendon, and the management of tears. The anatomy section will cover innervation, vascular supply and insertional anatomy of the subscapularis tendon. The function of the subscapularis in regards to both stability and motion of the glenohumeral joint will be examined. The focus of the article will then shift to the tears of the subscapularis, starting with an in depth look at the epidemiology and classification of these tears. The article will then cover the different imaging modalities and their utility in regards to subscapularis tears. Finally, the operative and non-operative management and indications for each modality will be discussed in detail.

Computational analysis of subscapularis tears and pectoralis major transfers on muscular activity

BACKGROUND

Pectoralis major is the most common muscle transfer procedure to restore joint function after subscapularis tears. Limited information is available on how the neuromuscular system adjusts to the new configuration, which could explain the mixed outcomes of the procedure. The purpose of this study is to assess how muscles activation patterns change after pectoralis major transfers and report their biomechanical implications.

METHODS

We compare how muscle activation change with subscapularis tears and after its treatment by pectoralis major transfers of the clavicular, sternal, or both these segments, during three activities of daily living and a computational musculoskeletal model of the shoulder.

FINDINGS

Our results indicate that subscapularis tears require a compensatory activation of the supraspinatus and is accompanied by a reduced co-contraction of the infraspinatus, both of which can be partially recovered after transfer. Furthermore, although the pectoralis major acts asynchronously to the subscapularis before the transfer, its activation pattern changes significantly after the transfer.

INTERPRETATION

The capability of a transferred muscle segment to activate similarly to the intact subscapularis is found to be dependent on the given motion. Differences in the activation patterns between intact subscapularis and the segments of pectoralis major may explain the difficulty in adapting psycho-motor patterns during the rehabilitation period. Thereby, rehabilitation programs could benefit from targeted training on specific motion and biofeedback programs. Finally, the condition of the anterior deltoid should be considered to improve joint function.

Ultrasonography Outperforms Magnetic Resonance Imaging in Diagnosing Partial-Thickness Subscapularis Tear

PURPOSE

To evaluate the diagnostic reliability of ultrasonography (US) and magnetic resonance imaging (MRI) for subscapularis (SSC) tears with shoulder arthroscopy as the gold standard and to investigate the diagnostic value of 2 MRI signs (lesser tuberosity cysts and subcoracoid cysts) for SSC tears.

METHODS

We consecutively enrolled 437 patients who were scheduled to undergo arthroscopic rotator cuff repair from January 2019 to December 2020. Patients with previous shoulder surgery or shoulder fracture, recurrent shoulder instability, and systemic inflammatory disease were excluded. Preoperative US and MRI of the shoulder were performed and interpreted with a standardized approach. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of US and MRI were calculated using arthroscopic findings as the gold standard.

RESULTS

Of the 437 patients, 157 had SSC tears confirmed at the time of arthroscopy, 126 of whom had partial-thickness tears. US correctly diagnosed 122 of 157 patients with SSC tears, with an overall sensitivity of 77.7% (confidence interval [CI] 70.6%-83.5%), which was significantly greater than that of MRI (49.7%, CI 42.0%-57.4%, P < .001). For partial-thickness SSC tears, US correctly diagnosed 93 of 126 positive patients and 276 of 311 negative patients. This resulted in a sensitivity of 73.8% (CI 65.5%-80.7%), specificity of 88.7% (CI 84.8%-91.8%), and accuracy of 84.4% (CI 80.7%-87.5%). As with MRI, the sensitivity, specificity, and accuracy were 38.1% (CI 29.7%-47.2%), 86.5% (CI 82.3%-89.9%), and 72.5% (CI 68.2%-76.5%), respectively. Lesser tuberosity cysts and subcoracoid cysts were 2 MRI signs with high specificity (98.2% and 94.6%); however, their sensitivities were relatively low (19.8% and 33.8%).

CONCLUSIONS

US is a reliable and accurate diagnostic method for SSC tears, especially in easily missed partial-thickness tears. Lesser tuberosity cyst and subcoracoid cyst are highly specific but insensitive MRI signs for SSC tear.

LEVEL OF EVIDENCE

Level I, diagnostic, testing of previously developed diagnostic criteria.

Imaging Review of Subscapularis Tendon and Rotator Interval Pathology

As the largest rotator cuff muscle, the subscapularis plays a major role in stabilizing the glenohumeral joint, in conjunction with surrounding rotator cuff structures. Injury to the subscapularis tendon can be isolated, but more commonly is seen in conjunction with supraspinatus tendon pathology. Injury can be associated with biceps pulley instability, superior labral anterior-posterior (SLAP) tears, humeral head subluxation, and anterosuperior and coracoid impingements. The involvement of the rotator interval can lead to what is called “the hidden lesion,” due to its difficulty to diagnose during arthroscopy. Understanding the anatomical relations of the subscapularis tendon with the rest of the rotator cuff and rotator interval, as well as common patterns of injury that involve the subscapularis tendon, can aid in proper diagnosis of these injuries leading to prompt surgical repair. This review describes the anatomy of the subscapularis muscle and tendon, and the magnetic resonance imaging (MRI) patterns of subscapularis tendon injury.

Arthroscopic Subscapularis Repair Using 18-Gauge Spinal Needle as a Suture Passer to Eliminate Iatrogenic Tendon Damage from Modern Suturing Devices

Suture passing devices are frequently used for subscapularis tendon repair. However, some of these devices can further damage the tendon by creating a larger tear. Use of an 18-gauge spinal needle as a suture passer helps eliminate damage to the tendon. By using its smaller diameter, the needle prevents tendon cut-through and enhances the precision of the repair.

Predicting the clinically significant subscapularis tendon tear: malposition and tear of the long head of the biceps tendon on shoulder magnetic resonance imaging

BACKGROUND

The diagnostic accuracy of magnetic resonance imaging (MRI) is low for detecting a subscapularis tendon tear.

PURPOSE

To identify MRI findings that may predict the presence of a clinically significant subscapularis tendon tear requiring surgical repair.

MATERIAL AND METHODS

We reviewed shoulder MR images of patients who had undergone arthroscopic rotator cuff repair at our institution between June 2018 and May 2019. Patients were divided into two groups: the study group (n = 51), with an intermediate- to high-grade partial thickness tear of the subscapularis tendon suspected on preoperative MRI and intermediate or higher grade of the tendon tear proven on arthroscopy; and the control group (n = 18), with an intermediate- to high-grade partial thickness tear of the subscapularis tendon suspected on preoperative MRI but no tear or low-grade partial thickness tear of the tendon shown on arthroscopy. Preoperative MR images were retrospectively evaluated by two readers for the size of the subscapularis tendon tear, bone reactions at the lesser tuberosity, and long head of the biceps tendon (LHBT) pathology.

RESULTS

The subscapularis tendon tear measured by reader 2 was larger in the study group than in the control group. The prevalence of a tear (P = 0.006 for reader 1; P = 0.011 for reader 2) and malposition (P < 0.001 for both readers) of the LHBT were significantly greater in the study group.

CONCLUSION

A tear and malposition of the LHBT on MR images may predict the presence of a clinically significant subscapularis tendon tear.

Arthroscopic Revision Rotator Cuff Repair: The Role of Previously Neglected Subscapularis Tears

BACKGROUND

Concomitant full-thickness tear of the subscapularis tendon is often neglected during primary posterosuperior rotator cuff repair, and its significance has not been investigated by any previous clinical study.

PURPOSE

To investigate (1) the clinical and radiological outcomes of revision arthroscopic rotator cuff repair and (2) the number of neglected concomitant subscapularis full-thickness tears in the revision of posterosuperior rotator cuff retears and their structural integrity after repair.

STUDY DESIGN

Case series, Level of evidence, 4.

METHODS

This study retrospectively examined 58 patients who underwent arthroscopic rotator cuff revision for a retear of a previously repaired posterosuperior rotator cuff. Preoperative and postoperative functional scores and active range of motion (ROM) were assessed. The initial and most recent follow-up magnetic resonance imaging scans before revision and arthroscopic findings at the time of primary repair were reviewed to determine whether the concomitant subscapularis tear was newly developed or preexisting. Final confirmation of the tendon's full-thickness tear was made during the revision procedure.

RESULTS

At final follow-up, mean functional shoulder scores and ROM improved significantly compared with the preoperative values (P < .001). Among the 58 revision cases, 25 (43.1%) had a neglected full-thickness tear of the subscapularis tendon. The fatty infiltration grade of the neglected subscapularis tear progressed from a mean of 1.1 before primary repair to a mean of 1.6 before revision, and the change indicated statistically significant deterioration (P < .001). Despite clinical improvement after revision surgery, the retear rate was considerable in the re-repaired cuff tendons (37.9%) as well as for the repaired concomitant subscapularis tears (24%).

CONCLUSION

Among revision rotator cuff repairs, 43.1% had neglected subscapularis tears, and fatty infiltration of these initially neglected subscapularis tendons showed further progression at the time of revision. The retear rate after the repair of neglected subscapularis tears was higher than expected. Thus, detecting and treating subscapularis tear via meticulous preoperative evaluation and thorough inspection during primary arthroscopy are essential.

Preoperative Magnetic Resonance Imaging Accurately Detects the Arthroscopic Comma Sign in Subscapularis Tears

PURPOSE

To assess the accuracy and reliability of routine preoperative magnetic resonance imaging (MRI) in the detection of the comma sign compared with the gold standard of arthroscopic findings.

METHODS AND MATERIALS

Preoperative MRI exams in consecutive patients undergoing arthroscopic subscapularis tendon repair, over a 5-year time frame, were retrospectively reviewed for full-thickness tears of the subscapularis and supraspinatus tendons, fatty atrophy of the subscapularis and supraspinatus muscles, and status of the long head of the biceps tendon. Each case was also evaluated for presence or absence of a comma sign on MRI. Surgical findings served as the diagnostic standard of reference in determination of a comma sign.

RESULTS

The study cohort included 45 male and 10 female patients (mean age, 56; range, 32-80 years). A comma sign was present at arthroscopy in 19 patients (34.5%). Interclass and intrarater correlation showed 100% agreement in preoperative assessment of a comma sign on MRI. MRI showed an overall accuracy of 83.6% in diagnosis of a comma sign (sensitivity, 63.2%; specificity, 94.4%; positive predictive value, 85.7%; negative predictive value, 82.9%; positive likelihood ratio, 11.37; negative likelihood ratio, 0.39). No statistically significant association was observed between an arthroscopic comma sign and patient demographics or MRI findings of full-thickness rotator cuff tears, muscle fatty atrophy, or long head of the biceps tendon pathology.

CONCLUSIONS

MR imaging illustrates excellent reliability and good specificity and accuracy in detection of the arthroscopic comma sign in the setting of subscapularis tendon tearing. Detection of a comma sign on MRI may be important preoperative planning information in the arthroscopic management of patients with subscapularis tendon tears.

LEVEL OF EVIDENCE

Level IV, retrospective diagnostic study.

Single-Portal, Single-Anchor Repair of a Superior Third Subscapularis Tear Using a Self-Punching Knotless Soft Suture Anchor

Numerous techniques exist for arthroscopic subscapularis repair with varying degrees of complexity based on tear morphology, all of which have established satisfactory outcomes in function and patient satisfaction. Arthroscopic subscapularis repair can require several working portals and suture anchors, increasing both technical complexity and operative time. This Technical Note describes an arthroscopic repair of a superior one-third subscapularis tear using a self-punching knotless soft suture anchor through a single anterior working portal. Thus, we offer a unique approach to arthroscopic repair of superior one-third subscapularis tears that is time-saving, reproducible, and highly efficient while minimizing iatrogenic damage and postoperative complications.

Analysis of the results and adverse factors of arthroscopic repair of degenerative subscapular lesions

OBJECTIVE

To carry out a review of degenerative subscapularis ruptures (SSC) after their arthroscopic repair and to evaluate whether the results are comparable in terms of pain and function to those of younger patients with traumatic ruptures.

METHODS

The data of 80 SSC tears of the 660 rotator cuff tears operated on by the same team of surgeons from June 2008 to June 2018 were retrospectively reviewed. The clinical data of the surgical indications were collected: age, gender, laterality, intervention delay, associated pathologies, location of pain, value of the Visual Analogue Scale (VAS) and the Constant-Murley test (CMT); surgical data were also collected: type and size of lesion, associated biceps injury and associated surgical procedure, coracoid stenosis and associated surgical procedure, number and type of anchors used. A statistical study was performed with multiple linear regression test, parametric tests (Student's t or ANOVA) and non-parametric tests.

RESULTS

Of 80 patients, 36 were women (45%) and 44, men (55%); mean age 61years (range 47 to 81); mean delay of surgery 3.5months (range 1 to 6); right shoulder affected in 46 cases (57.5%), left in 34 (42.5%); 22 (27.5%) were isolated lesions, 58 (72.5%) were associated with supraspinatus rupture (SE). The mean improvement was 5.0 points in terms of the VAS and 39.9 points on average in the CMT. New breakage rate, 1.25%. Adverse factors: size of the tear, delay in intervention, women. Patients with type I-B rupture have a better overall result in the CMT than types I-A and III. The longer the delay, the worse results are observed, both for the VAS and the CMT. Women present worse and statistically significant results both in the VAS (P=.00) and in the CMT (P=.01).

CONCLUSIONS

Excellent and good results have been obtained in this group of patients, but there are adverse factors such as the size of the tear, the duration of the symptoms and the association of other pathologies, especially in women.

Ultrasound evaluation of the rotator interval and adjoining tendons in shoulders with restricted movements: a technical note describing a simplified shoulder position

The rotator interval (RI) is a critical but complex anatomical structure for which musculoskeletal ultrasound provides an excellent imaging evaluation. In the patients with restricted and painful movements, the RI may not be visualised optimally as the conventional 'Modified Crass' positions may not be achievable. It can also be difficult to optimally evaluate the anterior supraspinatus and subscapularis tendons in such patients. We describe a simple shoulder position obviating need of pronounced supraspinatus stretch for better evaluation of the rotator interval and adjoining rotator cuff structures.

Arthroscopic Subscapularis Repair Using a Clever Hook and Lasso Loop Technique in the Beach Chair Position: A Simple and Reproducible Guide

Addressing subscapularis tendon pathology has garnered increased attention during shoulder arthroscopy in attempt to adequately restore glenohumeral force couples. The appropriate rebalancing of force couples of the rotator cuff musculature by repairing subscapularis tendon tears in patients with large rotator cuff tears has been shown to improve functional outcomes while decreasing retear rates. However, subscapularis tendon tears may be particularly challenging to diagnose and present a significant degree of technical difficulty with the description of multiple arthroscopic and open surgical techniques. In this comprehensive guide, we put forth a simple, concise, and reproducible arthroscopic technique using a Clever Hook and Lasso Loop stitch technique for repairing both high-grade partial and full-thickness tears of the subscapularis tendon.

The subscapularis tendon: A proposed classification system

BACKGROUND

The subscapularis muscle originates from the medial two-thirds and from the lower two-thirds of the groove on the subscapular fossa of the scapula and inserts into the lesser tubercle of the humerus. Our initial hypothesis is that it shows little morphological variation. The aim of this study is to demonstrate and classify the morphological variability of the subscapularis muscle.

METHODS

Classical anatomical dissection was performed on 64 upper limbs (44 females, 20 males, 30 left and 34 right, fixed in 10% formalin). The mean age "at death" of the cadavers was 75.6 years (range 48-95), and the group comprised equal numbers of female and male adults (Central European population). Upon dissection, the following morphological features were assessed: the number of tendons of the SM, the type of insertion of each tendon of the SM, morphometric measurements of the SM.

RESULTS

Four types of morphology (based on number of tendons) were observed in the cadavers. Type I was characterized by a single band. This was the most common type, occurring in 43.7% of all cases. Type II was characterized by a double tendon (superior and inferior); it occurred in 9.4%. Type III had three tendons (superior, middle, and inferior). It was the rarest type (7.8% of cases). Type IV, called "multiband", was the second most common (39.1%) and was divided into five subtypes.

CONCLUSIONS

The subscapularis muscle is highly morphologically variable. Knowledge of particular types of insertion is essential for both clinicians (for example orthopedists, physiotherapists) and anatomists.

Improving the detection of subscapularis tears using a specific transverse CT arthrography image

BACKGROUND

The prevalence of subscapularis (SSC) tendon tears is often underestimated. This negatively impacts the shoulder function because the SSC muscle is a powerful internal rotator. The primary aim of this study was to compare a blended clinical and radiological preoperative index of suspicion for SSC tears to the arthroscopic findings. The secondary aim was to compare the surgeon's and radiologist's index of suspicion to determine which is more accurate.

HYPOTHESIS

Analyzing a transverse image passing under the tip of the coracoid process, in combination with clinical examination, will be the standard for detecting SSC tears.

METHODS

This prospective study enrolled 50 consecutive patients who underwent shoulder arthroscopy. Preoperatively, four clinical tests were doneto detect SSC tears: lift-off, internal rotation lag sign, bear-hug, belly-press. A CT arthrography slice passing under the coracoid process tip was analyzed by the surgeon. The surgeon deduced a radiological index of suspicion for SSC tears then a blended clinical and radiological index of suspicion based on the clinical examination. Lastly, the surgeon looked at the radiologist's findings and index of suspicion for a lesion. The three indexes of suspicion were compared with the actual arthroscopy findings.

RESULTS

The surgeon's blended clinical and radiological index of suspicion was similar to his radiological index. Both of the surgeon's indexes of suspicion were higher than the radiologist's. The prevalence of SSC tears was 58 %.

DISCUSSION

We recommend doing multiple clinical tests as they complement each other in detecting SSC tears, since each one activates a different portion of the muscle. We advise surgeons to supplement their clinical examination by analyzing a specific image of the tendon below the coracoid, as the reference view for the starting point of SSC tears.

LEVEL OF EVIDENCE

IV, prospective diagnostic study on consecutive patients.

Electromyography of the Shoulder Musculature during Passive Rehabilitation Exercises

Background

Medical professionals remain conflicted about the best rehabilitation protocol a patient should perform after rotator cuff repair surgery. Exercises deemed passive may be activating the shoulder muscles to a moderate level, thus putting the surgical repair construct at risk for re-injury. The purpose of this study was to measure the activation of the rotator cuff and surrounding musculature during exercises used in physical therapy following rotator cuff repair surgery using electromyography (EMG).

Methods

Muscle activation was recorded in fourteen participants performing sixteen exercises. Four fine wire electrodes (supraspinatus, infraspinatus, subscapularis, teres minor) and six surface electrodes (upper and middle division of the trapezius, anterior, medial and posterior head of the deltoid, biceps brachii) were utilized. EMG activity values for each muscle were normalized to the maximum voluntary isometric contraction and activation levels were assessed.

Results

Twelve of the sixteen exercises tested were moderately active in the subscapularis muscle. The results show the subscapularis muscle was activated in all three planes of motion.

Discussion

Most exercises were found to have low activation levels for the supraspinatus, infraspinatus and teres minor muscles. While the exercises examined in this study appear to be safe for the more commonly repaired supraspinatus, caution should be used when administering exercises to individuals with repairs involving the subscapularis.

Evidence-Based Physical Examination for the Diagnosis of Subscapularis Tears: A Systematic Review

CONTEXT

There is a renewed interest in diagnosing and treating subscapularis tears, but there is a paucity of clinical guidance to optimize diagnostic decision-making.

OBJECTIVE

To perform a literature review to evaluate advanced maneuvers and special tests in the diagnosis of subscapularis tears and create a diagnostic algorithm for subscapularis pathology.

DATA SOURCES

PubMed, MEDLINE, Ovid, and Cochrane Reviews databases.

STUDY SELECTION

Inclusion criteria consisted of level 1 and 2 studies published in peer-reviewed scientific journals that focused on physical examination.

STUDY DESIGN

Systematic review.

LEVEL OF EVIDENCE

Level 2.

DATA EXTRACTION

Individual test characteristics (bear hug, belly press, lift-off, Napoleon, and internal rotation lag sign) were combined in series and in parallel to maximize clinical sensitivity and specificity for any special test evaluated in at least 2 studies. A secondary analysis utilized subjective pretest probabilities to create a clinical decision tree algorithm and provide posttest probabilities.

RESULTS

A total of 3174 studies were identified, and 5 studies met inclusion criteria. The special test combination of the bear hug and belly press demonstrated the highest positive likelihood ratio (18.29). Overall, 3 special test combinations in series demonstrated a significant impact on posttest probabilities. With parallel testing, the combination of bear hug and belly press had the highest sensitivity (84%) and lowest calculated negative likelihood ratio (0.21).

CONCLUSION

The combined application of the bear hug and belly press physical examination maneuvers is an optimal combination for evaluating subscapularis pathology. Positive findings using this test combination in series with a likely pretest probability yield a 96% posttest probability; whereas, negative findings tested in parallel with an unlikely pretest probability yield a 12% posttest probability.

Techniques and Tips for Identification of Comma Tissue in Subscapularis Tears

Identifying and repairing subscapularis tears can be challenging for the arthroscopic surgeon and is commonly related to the difficulty in accurately recognizing the distorted anatomy that may be encountered. Defining and differentiating this anterior glenohumeral joint anatomy are often made even more challenging in clinical situations in which large, retracted subscapularis and anterosuperior tears are present. Identifying the "comma tissue" during the initial arthroscopic assessment is very helpful because it provides an important anatomic landmark that not only serves to orient the surgeon but also facilitates reduction and repair of these tears. Identification of the comma tissue is sometimes a critical surgical step in subscapularis repair, and we provide tips and techniques that can aid the surgeon in reliably and reproducibly recognizing and incorporating the comma tissue.

Arthroscopic Subscapularis Repair Using a Subacromial View

As a result of the continued improvement in arthroscopic equipment and techniques, subscapularis tears are now more reliably identified and are being repaired at higher rates than previously reported. Whereas small upper-border subscapularis tears can usually be effectively managed using an intra-articular view, larger tears often cannot be fully visualized with a standard 30° arthroscope when viewed from the posterior portal. These tears may require either using a 70° arthroscope or viewing through the standard 30° arthroscope from a subacromial portal-site location to completely visualize the tear. This article illustrates and discusses the advantages of using a subacromial-space portal site to view and arthroscopically manage large subscapularis tears.

MR Imaging of the Rotator Cuff

The cause of rotator cuff tears is multifactorial with both intrinsic and extrinsic contributing factors. Understanding the normal MR anatomy of the rotator cuff and using an appropriate search pattern can help readers identify common pathologic conditions. Accurate designation using classification systems for tear thickness, size, and degree of retraction and muscle fatty infiltration and atrophy are important in guiding surgical management. Knowledge of common disease locations for the rotator cuff tendons can help focus reader searches and increase sensitivity.

Comparison of Functional and Radiological Outcomes of Tears Involving the Subscapularis: Isolated Subscapularis Versus Combined Anterosuperior Rotator Cuff Tears

Background:

Few studies have compared the clinical and radiological characteristics and outcomes in isolated subscapularis (SSC) and combined anterosuperior (AS) rotator cuff tears (RCTs). Furthermore, risk factors for retear after SSC repair and the effect of preoperative fatty degeneration require further evaluation.

Purpose:

To compare the functional and radiological outcomes of isolated SSC with combined AS RCTs after arthroscopic repair and to determine the risk factors for SSC retear in these 2 groups.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

Data from 30 patients in the isolated SSC group were compared with data from 110 patients in the combined AS group. All patients underwent primary arthroscopic rotator cuff repair between 2010 and 2016. Clinical outcomes were assessed through use of the visual analog scale for pain, American Shoulder and Elbow Surgeons score, and Simple Shoulder Test at a mean follow-up of 26.7 months (range, 24-96 months). SSC tendon integrity was examined via magnetic resonance imaging, computed tomography arthrogram, or ultrasonography at least 1 year after surgery.

Results:

The isolated SSC group had a greater proportion of males and the patients were younger compared with the combined AS group (both P < .050). The incidence of trauma was high but not significantly different between groups (56.7% vs 40.9%; P = .180). Clinical outcome measures and radiological outcomes in terms of retear were not statistically different between both groups (16.7% vs 8/5%; P = .337). The optimal cutoff values for the risk of SSC tendon retear in both groups were 19-mm retraction and 16-mm superoinferior dimension (P = .048). Unfavorable preoperative fatty degeneration of the SSC muscle (grades 3 and 4) was a significant risk factor for retear (odds ratio, 9.8; P < .001).

Conclusion:

Isolated SSC and combined AS RCTs were comparable except for patient age and sex; both had a high incidence of traumatic history. The current data suggest that the risk factors for retear after SSC repair in RCTs involving the SSC were tear size greater than 19 mm of retraction and unfavorable fatty degeneration (grade 3 or higher) of the SSC muscle.

Risk Factors for Rotator Cuff Disease: An Experimental Study on Intact Human Subscapularis Tendons

Although several studies revealed a multifactorial pathogenesis of degenerative rotator cuff disorders, the impact and interaction of extrinsic variables is still poorly understood. Thus, this study aimed at uncovering the effect of patient- and pathology-specific risk factors that may contribute to degeneration of the rotator cuff tendons. Between 2015 and 2018, 54 patients who underwent arthroscopic shoulder surgery at three specialized shoulder clinics were prospectively included. Using tendon samples harvested from the macroscopically intact subscapularis (SSC) tendon, targeted messenger RNA expression profile analysis was performed in the first cohort (n = 38). Furthermore, histological analyses were conducted on tendon tissue samples obtained from a second cohort (n = 16). Overall, both study cohorts were comparable concerning patient demographics. Results were then analyzed with respect to specific extrinsic factors, such as patient age, body mass index, current as well as previous professions and sport activities, smoking habit, and systemic metabolic diseases. While patient age, sports-activity level, and preexisting rotator cuff lesions were considered to contribute most strongly to tendinopathogenesis, no further coherences were found. With regards to gene expression analysis, change in expression correlated most strongly with patient age and severity of the rotator cuff pathology. Further, chronic disorders increased overall gene expression variation. Taken together, our study provides further evidence that tendon degeneration is the consequence of a multifactorial process and pathological changes of the supraspinatus tendon affect the quality of SSC tendon and most likely vice versa. Therefore, the rotator cuff tendons need to be considered as a unit when managing rotator cuff pathologies. © 2019 The Authors. Journal of Orthopaedic Research^® published by Wiley Periodicals, Inc. on behalf of Orthopaedic Research Society J Orthop Res 38:182-191, 2020.

The Middle Glenohumeral Ligament Test for the Diagnosis of Subscapularis Lesions

Arthroscopy has improved the diagnosis of subscapularis tendon lesions, and the outcomes of arthroscopic repair are satisfactory. Nonetheless, the diagnosis of some partial- and full-thickness subscapularis tears remains challenging. The middle glenohumeral ligament inserts distally into the articular surface of the subscapularis tendon and can be displaced when the subscapularis tendon is torn with retraction. This article describes the middle glenohumeral ligament test, which allows retracted lesions of the subscapularis tendon to be detected even if the superior edge is visible and normally placed. In addition, it allows control of the subscapularis tendon repair.

Multiple Subscapularis Tendon Sign: A New Risk Factor for Recurrence After Arthroscopic Anterior Shoulder Instability Surgery

Background:

Being able to predict recurrence after the treatment of shoulder instability would be helpful in planning the appropriate treatment.

Purpose:

To define the multiple subscapularis tendon sign (MSTS) as a novel anatomic variant and a possible risk factor for the recurrence of shoulder instability after anterior stabilization and to evaluate it, together with the other risk factors as described in the literature.

Study Design:

Case-control study; Level of evidence, 3.

Methods:

A total of 87 patients met the study criteria and underwent arthroscopic stabilization for anterior shoulder instability. The MSTS was evaluated in this study group. Age, sex, hand dominance, number of preoperative shoulder dislocations, history of overhead or contact sports participation, type of labral lesion, number of anchors used in surgery, presence of the drive-through sign, presence of the MSTS, Oxford Shoulder Score results, and the association of these parameters with recurrence were assessed. The mean follow-up time was 81.0 ± 27.9 months (range, 48-139 months).

Results:

Nine (10.3%) patients experienced recurrent instability. The presence of the MSTS (P = .009), existence of an anterior labroligamentous periosteal sleeve avulsion (ALPSA) lesion (P = .04), and history of overhead or contact sports participation (P = .04) were significant risk factors for recurrence. The recurrence rates were as follows: 30.7% with the MSTS; 40% with the MSTS and an ALPSA lesion; and 75% with the MSTS, an ALPSA lesion, and a history of overhead or contact sports participation.

Conclusion:

The MSTS is a variation of the anterior shoulder joint capsule. It is a sign of capsular insufficiency or thinning, which may be a risk factor for recurrence after anterior stabilization. Considering the low success rates of anterior capsulolabral repair in patients participating in overhead or contact sports, especially when an ALPSA lesion is present, encountering the MSTS during surgery in this at-risk group may be an indicator for the surgeon to choose the surgical procedure more carefully.