Diagnostic performance of clinical tests for subscapularis tendon tears

Long-term outcomes of anterior latissimus dorsi tendon transfer for irreparable subscapularis tears

Aims

Favourable short-term outcomes have been reported following latissimus dorsi tendon transfer for patients with an irreparable subscapularis (SSC) tendon tear. The aim of this study was to investigate the long-term outcomes of this transfer in these patients.

Methods

This was a retrospective study involving 30 patients with an irreparable SSC tear and those with a SSC tear combined with a reparable supraspinatus tear, who underwent a latissimus dorsi tendon transfer. Clinical scores and active range of motion (aROM), SSC-specific physical examination and the rate of return to work were assessed. Radiological assessment included recording the acromiohumeral distance (AHD), the Hamada grade of cuff tear arthropathy and the integrity of the transferred tendon. Statistical analysis compared preoperative, short-term (two years), and final follow-up at a mean of 8.7 years (7 to 10).

Results

There were significant improvements in clinical scores, in the range and strength of internal rotation and aROM compared with the preoperative values in the 26 patients (87%) who were available for long-term follow-up. These improvements were maintained between short- and long-term follow-ups. Although there was a decreased mean AHD of 7.3 mm (SD 1.5) and an increased mean Hamada grade of 1.7 (SD 0.5) at final follow-up, the rate of progression of cuff tear arthropathy remained low-grade. Comparison between the isolated SSC and combined SSC and reparable supraspinatus tear groups showed no significant differences. At final follow-up, one patient (3.8%) had undergone revision surgery to a reverse shoulder arthroplasty (RSA). No neurological complications were associated with the procedure.

Conclusion

Latissimus dorsi transfer for an irreparable SSC tendon tear resulted in a significant clinical improvement, particularly in pain, range and strength of internal rotation and aROM, which were maintained over a mean of 8.7 years following surgery. Given that this was a long-term outcome study, there was a low-grade progression in the rate of cuff tear arthropathy. Thus, the long-term clinical efficacy of latissimus dorsi tendon transfer in patients with irreparable SSC was confirmed as a joint-preserving procedure for these patients, suggesting it as an effective alternative to RSA in young, active patients without degenerative changes of the glenohumeral joint.

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.

Preoperative Shoulder MRI Findings to Predict Subscapularis Tendon Tear Requiring Surgical Repair

Purpose

This study aimed to investigate which indirect parameters on preoperative MRI were the principal predictors of subscapularis tendon tears (STTs) requiring surgical repair.

Materials and Methods

Preoperative MRI scans of 86 patients were retrospectively reviewed for visual assessment of the STT, pathology of the long head of the biceps tendon (LHBT), posterior decentering (PD) of the humeral head, humeral rotation, fatty degeneration, and subscapularis muscle atrophy. To evaluate atrophy, visual grading using the anatomical line connecting the coracoid tip to the glenoid base, designated as the base-to-tip line (BTL), and thickness measurements were performed in the en-face view.

Results

Arthroscopically, 31 patients (36%) exhibited Lafosse type III or IV STT and underwent surgical repair. LHBT pathology (p = 0.002), PD of the humeral head (p = 0.012), fatty degeneration (p < 0.001), and BTL grade (p = 0.003) significantly correlated with STT. In the multivariate analysis, PD of the humeral head (p = 0.011, odds ratio [OR] = 5.14) and fatty degeneration (p = 0.046, OR = 2.81) were independent predictors of STT.

Conclusion

PD of the humeral head and fatty degeneration of the subscapularis can help to diagnose clinically significant STT. Interpretation of these findings may contribute to the planning of an optimal surgical strategy.

Diagnostic Performance of Belly-Press Angle in Predicting the Severity of Subscapularis Tear

BACKGROUND

Neglected partial subscapularis tears often cause functional impairment even after repair of the supraspinatus and infraspinatus tear is done. Numerous physical examinations for detecting partial subscapularis tears have been described in previous studies.

PURPOSE

To analyze the relationship between the preoperative clinical features and the severity of a partial subscapularis tear and to provide diagnostic clues for patients requiring subscapularis repair.

STUDY DESIGN

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

METHODS

This retrospective study included 286 patients who underwent arthroscopic shoulder surgery between 2020 and 2022. Preoperative clinical features, including range of motion, functional scores, muscle strength ratio, modified belly-press test (measuring belly-press angle), and bear-hug test, were collected. Magnetic resonance imaging (MRI) evaluation was done according to the Yoo and Rhee classification. Types of subscapularis tear, supraspinatus lesion, and biceps lesion were recorded during arthroscopic surgery. A comparison of preoperative clinical features between the no-repair group (type 2A or less) and surgical repair group (type 2B or more) was done. The optimal cutoff value of the belly-press angle was determined and the diagnostic performance of the belly-press angle, bear-hug test, and MRI were evaluated using the receiver operating characteristic curve.

RESULTS

Among 286 patients, 189 (66.1%) had subscapularis tears with type 2A or more. There was a significant difference in muscle strength ratio of the belly-press (P < .001), belly-press angle (P < .001), and bear-hug test (P < .001) between the no-repair group (type 2A or less) and the surgical repair group (type 2B or more). With a belly-press angle of 15° as a new cutoff value, the modified belly-press test showed 67.6% sensitivity, 73.9% specificity, and 69.6% accuracy in detecting type 2B or higher subscapularis tear.

CONCLUSION

Patients with type 2A and 2B subscapularis tears (according to the Yoo and Rhee classification) showed differences in belly-press strength ratio, belly-press angle, and bear-hug test. The cutoff value of the 15° belly-press angle showed an accuracy of 69.6% in detecting subscapularis tears with type 2B or higher.

Correlation between preoperative clinical examination and intraoperatively found subscapularis tendon tear

PURPOSE

Analyze the diagnostic value for subscapularis (SSC) tendon tears, their correlation between pain and strength on clinical tests, and compare them with intraoperative arthroscopic findings to prove their diagnostic value.

METHODS

110 consecutive patients undergoing arthroscopic rotator cuff repair were reviewed and allocated to isolated SSC (n = 39) and combined anterosuperior tendon tear (n = 71) groups and analyzed. Preoperative clinical testing included belly press (BPT), bear hug (BHT), lift-off (LOT), palm-up (PUT), and Jobe test (JT). All tests were performed in two categories: pain (in 4 categories: 0, 5, 10, and 15) and strength (from 0 to 5). The tendon tears were intraoperatively reviewed and classified.

RESULTS

Mean age was 59 years (SD 10). The sensitivity of the BHT was 88.2% and 74.5% for BPT, while specificity was only 41.9% for BHT and 45% for BPT. Sensitivity of JT was 90.5% and 87.5% for PUT, while specificity was only 41% for JT and 28.2% for PUT. A low positive correlation for an intraoperative SSC lesion and the strength of BPT (Spearman rank correlation  - 0.425; p value < 0.0001) and the strength of BHT ( - 0.362; p value = 0.001) could be found. With linear regression analysis estimated by ordinary least squares, a correlation between BPT strength and surgical grade of SSC lesion (- 0.528; 95% CI, - 0.923 to - 0.133; pvalue < 0.01) was found.

CONCLUSION

The BHT showed a higher sensitivity for a SSC lesion, while the BPT had a higher correlation between preoperative testing, most notably internal rotation strength, and intraoperative surgical grade of the SSC tendon lesion.

LEVEL OF EVIDENCE

Level II, Prospective cohort study for Diagnostic tests.

Is it the subcoracoid impingement or the subacromial impingement that tears the subscapularis tendon? A comparison of the MRI findings of the operated and healthy shoulders of the patients

BACKGROUND

: The purpose of this study is to investigate whether the etiological factors accepted as causes of idiopathic subscapularis tears are true or not when the comparison is made with the opposite side healthy shoulder of the patients who underwent arthroscopic repair for an isolated subscapularis tear.

METHODS

Sixteen patients who underwent shoulder arthroscopy between February 2016 and January 2018 and were diagnosed with isolated subscapularis tear were evaluated. The coracohumeral distance (CHDax), coracoid overlap (CO), and tuberculum minus cysts (TMC) were evaluated on the axial images of the MRI studies while the acromiohumeral distance (AHDsag), CHDsag, and subscapularis tendon slip number (STSN) on the sagittal oblique images and the AHDcor and SLAP lesion on the coronal oblique images. Degeneration of the coracoacromial ligament was evaluated during arthroscopy.

RESULTS

The mean CHDsag (11.26-10.08), CHDax (10.63-9.98), CO (14.2-15.43), AHDsag (8-7.66), and AHDcor (7.65-7.68) measurements (operated side-healthy side, respectively) were statistically similar (p > 0.05). No statistically significant difference was found between TMC and STSN in healthy and operated shoulders (p > 0.05). There was mild coracoacromial ligament fraying in 4 (25%) and obvious coracoacromial ligament fraying in 8 (50%) which indicated subacromial impingement in 75% of the patients.

DISCUSSION

The parameters of the coracoid process did not reveal any significant difference between the operated (for an isolated subscapularis tear) and opposite-side healthy shoulders of the patients. However, coracoacromial ligament degeneration was present in 75% of the patients.

Machine learning model successfully identifies important clinical features for predicting outpatients with rotator cuff tears

PURPOSE

The aim of this study is to develop a machine learning model to identify important clinical features related to rotator cuff tears (RCTs) using explainable artificial intelligence (XAI) for efficiently predicting outpatients with RCTs.

METHODS

A retrospective review of a local clinical registry dataset was performed to include patients with shoulder pain and dysfunction who underwent questionnaires and physical examinations between 2019 and 2022. RCTs were diagnosed by shoulder arthroscopy. Six machine-learning algorithms (Stacking, Gradient Boosting Machine, Bagging, Random Forest, Extreme Gradient Boost (XGBoost), and Adaptive Boosting) were developed for the prediction. The performance of the models was assessed by the area under the receiver operating characteristic curve (AUC), Brier scores, and Decision curve. The interpretability of the predicted outcomes was evaluated using Shapley additive explanation (SHAP) values.

RESULTS

A total of 1684 patients who completed questionnaires and clinical tests were included, and 417 patients with RCTs underwent shoulder arthroscopy. In six machining learning algorithms for predicting RCTs, the accuracy, AUC values, and Brier scores were in the range of 0.81-0.86, 0.75-0.92, and 0.15-0.19, respectively. The XGBoost model showed superior performance with accuracy, AUC, and Brier scores of 0.85(95% confidence interval, 0.82-0.87), 0.92 (95% confidence interval,0.90-0.94), and 0.15 (95% confidence interval,0.14-0.16), respectively. The Shapley plot showed the impact of the clinical features on predicting RCTs. The most important variables were Jobe test, Bear hug test, and age for prediction, with mean SHAP values of 1.458, 0.950, and 0.790, respectively.

CONCLUSION

The machine learning model successfully identified important clinical variables for predicting patients with RCTs. In addition, the best algorithm was also integrated into a digital application to provide predictions in outpatient settings. This tool may assist patients in reducing their pain experience and providing prompt treatments.

LEVEL OF EVIDENCE

Level III.

The influence of testing positions and resistance locations on muscle activities during shoulder internal rotation strength measurements in young healthy adults

BACKGROUND

Although some tests of shoulder internal rotator strength including subscapularis are commonly used in clinical practice, the differences in shoulder muscle activities other than subscapularis muscle among those tests are not well understood. The purpose of this study was to examine the activities of the superficial shoulder muscles in addition to internal rotation strength during two belly-press and three lift-off test positions.

METHODS

Thirteen healthy young adult men (age 29.5 ± 5.4 years) were recruited for the present study. They performed isometric shoulder internal rotation against manual resistance during the belly-press test positions with two different resistance locations and the lift-off test with three different arm positions. The surface electromyographic activities of the superficial shoulder muscles, including the deltoid (anterior, middle, posterior), pectoralis major, long head of triceps and latissimus dorsi muscle, were collected and compared between the two belly-press tests, and among the three lift-off test positions (P < 0.05).

RESULTS

The belly-press test position with resistance to elbow showed significantly greater activities of the anterior and middle deltoid muscle than the original belly-press test; but showed significantly smaller activities of pectoralis major, triceps and latissimus dorsi muscle than the original belly-press test. Among the three lift-off tests, all muscle activities, except for the pectoralis major, were greater in the lift-off at L4/5 than in the lift-off at buttock and thigh. Lift-off at thigh showed significantly smaller activity of pectoralis major than the lift-off at L4/5 and buttock.

CONCLUSIONS

The findings of the present study suggest that clinician should give attention to compensatory motions by excessive shoulder extensor and adductor muscle activities for the original belly press test, by excessive deltoid muscle activities for the modified belly-press, and by excessive shoulder extensor muscle activities for the lift off test in the inferior arm positions.

[Development of a risk stratification model for subscapularis tendon tear based on patient-specific data from 528 shoulder arthroscopy]

OBJECTIVE

To identify and screen sensitive predictors associated with subscapularis (SSC) tendon tear and develop a web-based dynamic nomogram to assist clinicians in early identification and intervention of SSC tendon tear.

METHODS

Between July 2016 and December 2021, 528 consecutive cases of patients who underwent shoulder arthroscopic surgery with completely MRI and clinical data were retrospectively analyzed. Patients admitted between July 2016 and July 2019 were included in the training cohort, and patients admitted between August 2019 and December 2021 were included in the validation cohort. According to the diagnosis of arthroscopy, the patients were divided into SSC tear group and non-SSC tear group. Univariate analysis, least absolute shrinkage and selection operator (LASSO) method, and 10-fold cross-validation method were used to screen for reliable predictors highly associated with SSC tendon tear in a training set cohort, and R language was used to build a nomogram model for internal and external validation. The prediction performance of the nomogram was evaluated by concordance index (C-index) and calibration curve with 1 000 Bootstrap. Receiver operating curves were drawn to evaluate the diagnostic performance (sensitivity, specificity, predictive value, likelihood ratio) of the predictive model and MRI (based on direct signs), respectively. Decision curve analysis (DCA) was used to evaluate the clinical implications of predictive models and MRI.

RESULTS

The nomogram model showed good discrimination in predicting the risk of SSC tendon tear in patients [C-index=0.878; 95% CI(0.839, 0.918)], and the calibration curve showed that the predicted results were basically consistent with the actual results. The research identified 6 predictors highly associated with SSC tendon tears, including coracohumeral distance (oblique sagittal) reduction, effusion sign (Y-plane), subcoracoid effusion sign, biceps long head tendon displacement (dislocation/subluxation), multiple posterosuperior rotator cuff tears (≥2, supra/infraspinatus), and MRI suspected SSC tear (based on direct sign). Compared with MRI diagnosis based on direct signs of SSC tendon tear, the predictive model had superior sensitivity (80.2% vs. 57.0%), positive predictive value (53.9% vs. 53.3%), negative predictive value (92.7% vs. 86.3%), positive likelihood ratio (3.75 vs. 3.66), and negative likelihood ratio (0.25 vs. 0.51). DCA suggested that the predictive model could produce higher clinical benefit when the risk threshold probability was between 3% and 93%.

CONCLUSION

The nomogram model can reliably predict the risk of SSC tendon tear and can be used as an important tool for auxiliary diagnosis.

Diagnostic Accuracy of Clinical Tests for Subscapularis Tears: A Systematic Review and Meta-analysis

Background:

Previous systematic reviews and meta-analyses on the diagnostic accuracy of shoulder clinical tests do not reach conclusions regarding subscapularis tears.

Purpose:

To compare the diagnostic accuracy of commonly used clinical tests for subscapularis tears.

Study Design:

Systematic review; Level of evidence, 3.

Methods:

An electronic literature search was conducted using Medline, Embase, and the Cochrane Library/Central. Eligibility criteria were original clinical studies reporting the diagnostic accuracy of clinical tests to diagnose the presence of rotator cuff tears involving the subscapularis.

Results:

The electronic literature search returned 2212 records, of which 13 articles were eligible. Among 8 tests included in the systematic review, the lift-off test was most frequently reported (12 studies). Four tests were eligible for meta-analysis: bear-hug test, belly-press test, internal rotation lag sign (IRLS), and lift-off test. The highest pooled sensitivity was 0.55 (95% CI, 0.28-0.79) for the bear-hug test, while the lowest pooled sensitivity was 0.32 (95% CI, 0.13-0.61), for the IRLS. In all tests, pooled specificity was >0.90.

Conclusion:

Among the 4 clinical tests eligible for meta-analysis (bear-hug test, belly-press test, IRLS, and lift-off test), all had pooled specificity >0.90 but pooled sensitivity <0.60. No single clinical test is sufficiently reliable to diagnose subscapularis tears.

Registration:

PROSPERO (CRD42019137019).

Evaluation of subscapularis tendon tears of the anterosuperior aspect using radial-sequence magnetic resonance imaging

Background

Magnetic resonance imaging (MRI) is widely used to diagnose subscapularis tendon tears; however, it is difficult to assess the anterosuperior aspect of these tears. Radial-sequence MRI can reveal the fiber components of the anterosuperior aspect, from perpendicular, by overcoming the partial volume effect. We aimed to classify the insertion of subscapularis tendon tears on radial-sequence MRI and determine the effectiveness of radial-sequence MRI for subscapularis tendon tear assessments.

Methods

We retrospectively investigated 196 patients (mean age, 66.7 ± 9.0 years; 118 men, 78 women) who underwent 1.5 T MRI before arthroscopic rotator cuff repair. Radial-sequence MRI findings of the anterosuperior aspect insertion of the subscapularis tendon were classified into five grades, and intraoperative findings compared with preoperative conventional MRI and radial-sequence MRI. We calculated sensitivity, specificity, accuracy, and positive and negative predictive values. Interobserver and intraobserver reliability for radial-sequence MRI classification was calculated using kappa (κ).

Results

Conventional MRI sensitivity of subscapularis tendon tears was 45.3%; specificity, 95.8%; accuracy, 82.1%; positive predictive value, 80.0%; and negative predictive value, 82.5%. Radial-sequence MRI sensitivity was 92.5%; specificity, 88.1%; accuracy, 89.3%; positive predictive value, 74.2%; and negative predictive value, 96.9%. Sensitivity (P < .001), accuracy (P = .04), specificity (P = .02), and negative predictive values (P < .001) in radial-sequence MRI were significantly higher than those in conventional MRI. Intraobserver and interobserver reliabilities for radial-sequence MRI classification were κ = 0.78 and 0.65, respectively, corresponding to high reproducibility, and defined as good.

Conclusion

We provide evidence that radial-sequence MRI is an effective tool to evaluate subscapularis tendon tears, especially before surgery.

Combined clinical test and magnetic resonance imaging have similar diagnostic values in the diagnosis of subscapularis tear

PURPOSE

The aim of the present study was to compare the diagnostic values of clinical tests and magnetic resonance imaging (MRI) which used for the diagnosis of subscapularis (SSc) tears in the patients who underwent arthroscopic rotator cuff surgery.

METHODS

Two-hundred and nine consecutive patients who underwent arthroscopic rotator cuff surgery between 2015 and 2019 were analyzed. The lift-off test, belly-press test and bear-hug test were performed preoperatively. 1.5 T MRI scans of all patients were evaluated for SSc integrity. The diagnostic values of both clinical tests and MRI were calculated. SSc tears were graded according to Fox and Romeo. Arthroscopic findings were used as the gold standard for diagnosis of SSc tears.

RESULTS

There were 54 SSc tears accounting for an prevalence of 29%. The BHT showed the greatest sensitivity for both type II-II-IV (73.3%) and all types of (68.5%) SSc tears. The sensitivity and specificity of the combined test and MRI were 91.1-87.2% and 93.3-90.8% in Type II-III-IV SSc tears, respectively, and 81.5-88.6% and 88.9-94.7% in all SSc tears, respectively. There were no statistically significant difference between combined test and MRI in terms of sensitivity and specificity (n.s.).

CONCLUSION

The present study is the first that compared both clinical tests and MRI with arthroscopic findings in terms of sensitivity and specificity in the same patient group. A combination of clinical tests increases their diagnostic values and shows similar sensitivity and specificity as MRI.

LEVEL OF EVIDENCE

I.

Evidence-Based Examination Techniques for the Shoulder Joint

OBJECTIVE

Digitalisation now almost covers all areas of medical student teaching. Teaching videos are a good way to help students learn practical skills. The existing evidence is a recognised aid for the classification of the respective technology.

METHOD

This video presents the usual examination techniques of the shoulder joint on a patient with an unstable shoulder. The respective techniques, if available, were backed up with appropriate evidence.

CONCLUSION

The examination techniques presented allow students to view them in a standardized manner on a patient. The evidence for the examination techniques can help with the classification of the respective technique.

Evaluating subscapularis tendon tears on axillary lateral radiographs using deep learning

OBJECTIVE

To develop a deep learning algorithm capable of evaluating subscapularis tendon (SSC) tears based on axillary lateral shoulder radiography.

METHODS

A total of 2,779 axillary lateral shoulder radiographs (performed between February 2010 and December 2018) and the patients' corresponding clinical information (age, sex, dominant side, history of trauma, and degree of pain) were used to develop the deep learning algorithm. The radiographs were labeled based on arthroscopic findings, with the output being the probability of an SSC tear exceeding 50% of the tendon's thickness. The algorithm's performance was evaluated by determining the area under the receiver operating characteristic curve (AUC), sensitivity, specificity, negative predictive value (NPV), and negative likelihood ratio (LR-) at a predefined high-sensitivity cutoff point. Two different test sets were used, with radiographs obtained between January and December 2019; Test Set 1 used arthroscopic findings as the reference standard (n = 340), whereas Test Set 2 used MRI findings as the reference standard (n = 627).

RESULTS

The AUCs were 0.83 (95% confidence interval, 0.79-0.88) and 0.82 (95% confidence interval, 0.79-0.86) for Test Sets 1 and 2, respectively. At the high-sensitivity cutoff point, the sensitivity, NPV, and LR- were 91.4%, 90.4%, and 0.21 in Test Set 1, and 90.2%, 89.5%, and 0.21 in Test Set 2, respectively. Gradient-weighted Class Activation Mapping identified the subscapularis insertion site at the lesser tuberosity as the most sensitive region.

CONCLUSION

Our deep learning algorithm is capable of assessing SSC tears based on changes at the lesser tuberosity on axillary lateral radiographs with moderate accuracy.

KEY POINTS

• We have developed a deep learning algorithm capable of assessing SSC tears based on changes at the lesser tuberosity on axillary lateral radiographs and previous clinical data with moderate accuracy. • Our deep learning algorithm could be used as an objective method to initially assess SSC integrity and to identify those who would and would not benefit from further investigation or treatment.

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.

A novel diagnostic method to predict subscapularis tendon tear with sagittal oblique view magnetic resonance imaging

PURPOSE

To find novel measurement guidelines correlating with known tear size on two sagittal oblique views (en-face view and Y-view).

METHODS

From a series of arthroscopic rotator cuff repair cases between 2012 and 2015, 50 patients were randomly selected from each of six subscapularis tear classifications. Due to rarity of type IV lesions, 272 shoulders were included. En-face view and Y-view in sagittal plane MRI were selected. Image evaluation was retrospectively performed by two researchers independently. In en-face view, anatomical line connecting the coracoid tip to the glenoid base designated as the base-to-tip line was used for thickness measurement and classification. Grading according to base-to-tip line, overlapped segment of base-to-tip line, thickness of subscapularis, and fluid accumulation were measured. In Y-view, a tangent line was drawn through the scapular spine and the coracoid. Parallel lines were then made. Grading according to tangent line, vertical length, cephalic width, caudal width, and fluid accumulation was measured.

RESULTS

In en-face view, grading according to base-to-tip line and overlapped segment of base-to-tip line showed differences in subscapularis tendon tear types IIB, III, and IV compared to the normal group. Thickness of subscapularis showed differences in types III and IV. No significant difference was observed in fluid accumulation. In Y-view, grading according to tangent line, vertical length, cephalic width, and fluid accumulation showed significant differences in types III and IV. Caudal width in Y-view was significantly different only in type IV.

CONCLUSION

Several measurement parameters in two additional views in sagittal-oblique MRI (en-face view and Y-view) showed different degrees of subscapularis tendon tears. Grading of base-to-tip line is easy to use and helps diagnose partial subscapularis tear.

LEVEL OF EVIDENCE

III.

Arthroscopic Repair of an Isolated Subscapularis Tendon Rupture in an Adolescent Patient

Arthroscopic repair of an isolated subscapularis tendon rupture has been previously described in the adult population; however, the technique has yet to be described in a pediatric patient. In this Technical Note, we describe an arthroscopic repair of an isolated subscapularis tendon rupture with concomitant mini-open suprapectoral biceps tenodesis in an adolescent patient. Standard anterior and posterior portals are established with an accessory portal in the anterosuperior angle of the acromion. A 0-PDS suture is used to pass strands of suture tape through the inferolateral and superolateral aspects of the subscapularis tendon. Suture tape is passed through a suture anchor and the accessory portal and is fixated at the junction of the inferior one-third and superior two-thirds of the subscapularis tendon footprint and at the junction of the superior one-third and inferior two-thirds of the subscapularis tendon footprint. Following subscapularis tendon fixation, biceps tenodesis is performed through either a mini-open subpectoral or arthroscopic suprapectoral approach. This described technique allows for full visualization of the subscapularis tendon and lesser tuberosity. Additionally, this technique allows for accurate placement of suture anchors to maximize footprint coverage and appropriate graft tensioning.