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

The Subscapularis Healing Index: A New Scoring System for Predicting Subscapularis Healing After Arthroscopic Repair

BACKGROUND

Previous research has emphasized the effect of prognostic factors on arthroscopic rotator cuff repair (ARCR) success, but a specific focus on subscapularis (SSC) tendon repair healing is lacking.

PURPOSE

To identify prognostic factors for SSC healing after ARCR and develop the Subscapularis Healing Index (SSC-HI) by incorporating these factors.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

This was a retrospective study using prospectively maintained data collected from patients with isolated or combined SSC tears who underwent ARCR between 2011 and 2021 at a single institution with a minimum 2-year follow-up. Functional outcomes were assessed using the American Shoulder and Elbow Surgeons (ASES) score, Subjective Shoulder Value (SSV), and visual analog scale (VAS) pain scale. SSC tendon healing was evaluated via ultrasound at the final follow-up. Multivariate logistic regression analysis was performed to determine the factors affecting SSC healing, and based on these factors, the SSC-HI, which ranges from 0 to 15 points, was developed using odds ratios (ORs).

RESULTS

Among 1018 ARCR patients, 931 met the inclusion criteria; 279 returned voluntarily for postoperative SSC ultrasound assessment. The overall healing failure rate was 10.8% (30/279). Risk factors for healing failure included female sex (P = .008; OR, 3.119), body mass index (BMI) ≥30 (P = .053; OR, 2.323), supraspinatus fatty infiltration ≥3 (P = .033; OR, 3.211), lower SSC fatty infiltration ≥2 (P = .037; OR, 3.608), and Lafosse classification ≥3 (P = .007; OR, 3.224). A 15-point scoring system comprised the following: 3 points for female sex, 2 points for BMI ≥30, 3 points for supraspinatus fatty infiltration ≥3, 4 points for lower SSC fatty infiltration ≥2, and 3 points for Lafosse classification ≥3. Patients with ≤4 points had a 4% healing failure rate, while those with ≥9 points had a 55% rate of healing failure. Patients with a healed SSC reported significantly higher ASES (healed SSC: ΔASES, 44.7; unhealed SSC: ΔASES, 29; P < .01) and SSV (healed SSC: ΔSSV, 52.9; unhealed SSC: ΔSSV, 27.5; P < .01) and lower VAS (healed SSC: ΔVAS, -4.2; unhealed SSC: ΔVAS, -3; P < .01) scores compared with those with an unhealed SSC.

CONCLUSION

The SSC-HI scoring system integrates clinical and radiological factors to predict SSC healing after surgical repair. Successful SSC healing was found to be associated with enhanced functional outcomes, underscoring the clinical relevance of SSC healing prediction in the management of these tears.

Arthroscopic repair for isolated subscapularis tear: successful functional outcomes and high tendon healing rate can be expected nine years after surgery

BACKGROUND

Literature describing outcomes and integrity after isolated subscapularis (SSC) tendon repair is emerging but remains limited to a few small case series with short-term follow-up. The aim of this study was to evaluate the long-term clinical outcomes and repair integrity in patients who underwent arthroscopic repair of isolated SSC tears.

METHODS

A retrospective study was conducted with the following inclusion criteria: (1) primary and elective shoulder arthroscopy for isolated SSC repair, (2) type III (a full-thickness tear in the upper two-thirds of the tendon) or IV (a complete tear without tendon retraction) SSC tear according to the Lafosse classification, and (3) a minimum 24-month follow-up. Preoperatively, the range of motion (ROM) and the Constant-Murley score (CMS) and at follow-up, the ROM, the University of California-Los Angeles (UCLA) Shoulder Rating Scale, the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire, and the CMS were evaluated; an ultrasonographic assessment of tendon healing was performed according to the Sugaya classification.

RESULTS

The final sample consisted of 45 patients with an average age of 55 ± 9 years. After a mean follow-up time of 107 ± 54 months, the mean UCLA and DASH scores were 8.7 ± 1.3 and 42.2 ± 6.4, respectively. ROM and CMS showed statistically significant improvements (all P < .001). Before surgery, the mean CMS was 49% that of sex- and age-matched healthy individuals, and all patients showed a CMS lower than the normative data. At the final follow-up visit, the mean CMS was 94.2% that of sex- and age-matched healthy individuals, and no patients showed CMS of 30 or less. The mean increase in the CMS was 41.4 ± 9.8 points (range, 23-60 points). The ultrasonographic assessment showed SSC tendon healing in 39 (86.7%) cases; tendon retear was recorded in 5 (13.3%) cases. All scores directly correlated with the healing of the tendon. A higher postoperative DASH score was associated with male sex (P = .039, β = 5.538) and a longer follow-up period (P = .044, β = 0.001). The postoperative CMS (P < .001) and UCLA scores (P = .001) were significantly higher in patients younger than 60 years of age at surgery than in older individuals.

CONCLUSION

Arthroscopic repair of isolated SSC tears achieves excellent clinical and functional results at a mean of 9 years postoperatively, with a satisfactory healing rate. Better functional outcomes correlate with SSC tendon integrity and were observed in male patients and in those younger than 60 years at surgery.

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.

Postoperative Antiosteoporotic Treatment with Zoledronic Acid Improves Rotator Cuff Healing but Does Not Improve Outcomes in Female Patients with Postmenopausal Osteoporosis: A Prospective, Single-Blinded, Randomized Study

PURPOSE

To investigate the effect of the antiosteoporotic agent zoledronic acid (ZA) on rotator cuff healing and clinical outcomes in patients with postmenopausal osteoporosis.

METHODS

We prospectively enrolled 138 female patients with postmenopausal osteoporosis who were scheduled to undergo arthroscopic rotator cuff repair (ARCR) from March 2020 to March 2021. Patients were randomly allocated to the ZA group (ARCR followed by intravenous ZA infusions at postoperative Day 1 and 1 year later) and the control group (ARCR alone). All patients were followed up for 24 months. Tendon healing was evaluated by ultrasonography at 6 weeks and 24 months after surgery. The American Shoulder and Elbow Surgeons (ASES) score, Western Ontario Rotator Cuff (WORC) index, and Numeric Rating Scale (NRS) for pain were recorded at each follow-up, and the minimal clinically important difference (MCID) was calculated.

RESULTS

A total of 124 patients were included in the final analysis, 61 in the ZA group and 63 in the control group. There was no statistically significant difference in participant characteristics between the 2 groups. The ZA group had a significantly higher tendon healing rate than the control group at 2 years after surgery (odds ratio = 5.0; 95% confidence interval [CI], 1.4-18.7; P = .014). Regarding clinical outcomes, 100% of patients exceeded the MCID in both groups, and no significant differences were found at 2 years after surgery between the 2 groups (ASES: 2.5 [95% CI, -2.2 to 7.2; P = .291]; WORC index: 4.5 [95% CI, -0.117 to 9.117; P = .056]; NRS: -0.1 [95% CI, -0.3 to 0.1; P = .394]).

CONCLUSIONS

Antiosteoporotic treatment with ZA reduced the retear rate but did not significantly influence the clinical outcomes after ARCR in female patients with postmenopausal osteoporosis. Outcomes of ARCR showed good results in both groups and exceeded the MCID.

LEVEL OF EVIDENCE

Level I, randomized controlled trial.

Clinical Outcomes and Tendon Healing After Arthroscopic Isolated Subscapularis Tendon Repair: Results at Midterm Follow-up

Background

Few studies have reported clinical outcomes and tendon healing rates after arthroscopic isolated subscapularis (SSC) repair (AISR).

Purpose/Hypothesis

The primary purpose of this study was to evaluate clinical outcomes and tendon healing after AISR. It was hypothesized that AISR would result in satisfactory clinical outcomes along with a high rate of tendon healing at the midterm follow-up. The secondary purpose was to assess the influence of tear size and muscle atrophy on SSC tendon healing and patient-reported outcomes. It was hypothesized that both would be negatively correlated with healing but would have no effect on clinical outcomes .

Study Design

Case series; Level of evidence, 4.

Methods

A retrospective analysis was conducted on prospectively collected data for 77 patients who underwent primary AISR between 2011 and 2021 at a single institution, with a minimum 2-year postoperative follow-up for all patients. Functional outcomes were assessed using the American Shoulder and Elbow Surgeons (ASES) score, the Subjective Shoulder Value (SSV), and the visual analog scale for pain. Repair techniques and concomitant procedures were also collected. SSC tendon healing was evaluated via ultrasound at the final follow-up. Linear regression analysis was performed to determine factors affecting SSC healing.

Results

The mean follow-up was 58.1 ± 3.3 months. ASES scores significantly improved from 41.5 to 81.6, and the SSV improved from 38.2 to 80.5 (P < .01 for both). Among the 40 patients (51.9%) who underwent postoperative ultrasound, 87.5% showed complete tendon healing. There were no significant differences in outcome scores between healed and unhealed tendons. Increased muscle atrophy and larger tears were correlated with failure of SSC healing (β = -0.285 [P = .015] and β = -0.157 [P = .045], respectively).

Conclusion

Improved clinical outcomes and an overall high rate of tendon healing were seen at the midterm follow-up after AISR. Smaller tear sizes with less muscle atrophy were correlated with improved tendon healing. However, even when the tendon incompletely healed, the procedure improved functional outcomes.

Is It Time to Rethink the Relationship Between Subscapularis Tears and the Long Head of Biceps Tendon?

Introduction Pre-operative diagnosis of subscapularis tears remains a difficult challenge. Ultrasound has been shown to be ineffective at directly detecting subscapularis tears. It has been widely accepted that medial subluxation of the long head of biceps tendon (LHBT) is associated with full-thickness subscapularis tears. The aims of this study are to assess whether LHBT subluxation on ultrasound scanning has any predictive value for subscapularis tears and to determine the relationship between LHBT subluxation and subscapularis tears at arthroscopy. Methods Pre-operative ultrasound and arthroscopic findings for patients undergoing arthroscopic rotator cuff repair at our institution between March 2011 and January 2016 were analysed. The accuracy of LHBT subluxation on ultrasound and at arthroscopy as a predictor of subscapularis tears at arthroscopy was calculated. The correlation between LHBT subluxation and subscapularis tears was determined. A standardised technique was used for ultrasound scans, and the grade of the sonographer was recorded. Results Three hundred fifty-nine rotator cuff repairs were performed. Twenty-four patients had a subluxed LHBT. Ultrasound was poorly sensitive (50%), and a subluxed LHBT on ultrasound only correlated very weakly with subscapularis tears at arthroscopy (R = 0.268, p<0.001). At arthroscopy, 92 patients had full-thickness subscapularis tears. Of these, only 16 patients (17%) had a subluxed/dislocated LHBT. Of the 24 patients with a subluxed LHBT, eight had no subscapularis tears. Thus, LHBT subluxation/dislocation only correlated weakly with full-thickness subscapularis tears (R=0.252, p<0.001). Conclusion Due to their close anatomical relationship, traditional teaching suggests subscapularis tears are associated with medial LHBT subluxation. Our data indicate that, contrary to popular belief, the two are only weakly correlated. In our series, the majority of patients with subscapularis tears (83%) had their LHBT in-groove. The authors therefore recommend high vigilance during arthroscopy for the diagnosis and repair of subscapularis tears, regardless of pre-operative ultrasound findings and the intra-operative position of the LHBT.

Arthroscopic subscapularis repair using the subscapularis interlocking (SICK)-stitch technique leads to restoration of clinical function with low complication and revision rates

Background

The purpose of this study is to determine the mid-term outcome after arthroscopic subscapularis tendon (SCP) reconstruction using the subscapularis interlocking (SICK)-stitch technique. The hypotheses are that arthroscopically repaired SCP lesions using the SICK-stitch show a good restoration of shoulder function with low complication and failure rates.

Methods

This is a retrospective monocentric study of n = 199 patients (n = 106 female) with arthroscopically treated SCP tears with the interlocking (SICK) stitch technique from July 2013 to October 2018. Inclusion criteria: minimum follow-up of 2 years. Exclusion criteria: irreparable and massive cuff tears, osteoarthritis, and fractures. The postoperative assessment consisted of the range of motion, constant score, simple shoulder test, simple shoulder value, disability of the shoulder and arm score, short form 12, and patient satisfaction.

Results

Mean age was 61 years (25-83); n = 4 (2%) patients were lost to follow-up with mean follow-up time of 63.6 months (36-96). Additional supraspinatus tendon lesions (n = 147) were repaired in n = 101 cases. SCP grading (n = 69) (35% traumatic) (Fox/Romeo): n = 113 grade II, n = 71 grade III, n = 11 grade IV. A positive preoperative lift-off test (n = 132, 68%) was corrected in n = 124 (94%) of cases. Ninety seven percent of patients would undergo surgery again with a mean satisfaction score of 14.4/15. Results at final follow-up (data: mean pre; post; P value): lexion (130; 166; .001), abduction (123;159; .001), external rotation (35;82; .001), internal rotation (52; 68; .07), constant score (50; 82; .001), disability of the shoulder and arm score (40; 19; .001), simple shoulder test (5; 10; .001), and simple shoulder value (44; 83; .001) significantly improved. The mean physical health scale short form 12 was 46 (24-63) and 51 (15-66) for mental health. Age, body mass index, SCP-grading, and supraspinatus tendon repair did not significantly affect any outcome parameter. Three (1.5%) patients underwent revision surgery, of which 1 (0.5%) had an infection.

Conclusion

Two years after arthroscopic SCP repair using the SICK-stitch technique, we observed excellent restoration of clinical function with low complication and revision rates. The SICK-stitch technique thus represents a good and reliable therapeutic option for the arthroscopic repair of SCP lesions.

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.

Editorial Commentary: Magnetic Resonance Imaging Is Generally Superior to Ultrasound for Evaluation of Rotator Cuff Pathology: If Unrecognized Subscapularis Pathology Is Suspected After Magnetic Resonance Imaging, Ultrasound Can Then Be Performed

The advantages of using ultrasound over magnetic resonance imaging (MRI) in the diagnosis of rotator cuff pathology include patient and technical factors. Patient factors include the lack of claustrophobia or positioning constraints. Technical considerations include dynamic and real-time assessment, absence of contraindications due to implants, decreased cost, and portability. However, the limitations of ultrasound include operator dependency and skill, limited availability of experienced ultrasonographers, decreased sensitivity for other shoulder pathology, and possible less sensitivity for some types of rotator cuff pathology. In my practice, MRI, when indicated, is still the test of choice, as it is readily available, more versatile in diagnosing a wide range of shoulder pathologies, and not dependent on the availability of a skilled ultrasound operator. Should there still be concern for an unrecognized partial subscapularis tendon injury after MRI, ultrasound can then be performed.