Prospective Randomized Comparative Study of Outcome of Subscapularis Tear

The purpose of this study was to report actual percentage of subscapularis tear in concomitant with supraspinatus tendon tear (with or without infraspinatus tear) and investigate the amount of contribution of subscapularis repair as to the outcome of whole rotator cuff repair in terms of its clinical and radiologic aspects.

Prospective randomized controlled study was designed to evaluate subscapularis repair in anterosuperior rotator cuff tear compared with debridement of the subscapularis tear. After identification of the subscapularis tear arthroscopically, final eligibility of participants for the study was established on the basis of intra-operative arthroscopic inspection of the subscapularis using 70 degrees arthroscope. Once eligibility was confirmed, patients were randomized to one of two arthroscopic methods; repair (group A) or debridement (group B) of the subscapularis tear. The treatment allocations were decided through an interphone by "Research Coordinator". Block randomization was performed and no stratification was performed. Random Sequence Generator (Random.org) was used for the randomization process by given number whose digit was residue of modulo 2 (0 - group A, 1 - group B). Sequence Boundaries was 1 (smallest value) to 300 (largest value) based on the number calculated from power analysis. After randomization, patients underwent arthroscopic repair or debridement of the subscapularis tear. Size of the rotator cuff tear was also determined by the arthroscopic finding (small-to-medium, medium-to-large, large-to-massive). When full-thickness tear was confined to supraspinatus, the tear was called small-to-medium size tear. Medium-to-Large size tear was defined as complete full-thickness supraspinatus tear combined with incomplete full-thickness infraspinatus tear. Large-to-massive tear consisted of complete full-thickness tear of supraspinatus and infraspinatus or complete full-thickness tear of supraspinatus and subscapularis or complete 3-tendon tears. Postoperatively, rehabilitation was identical for both groups and consisted of sling immobilization for six weeks. Pulley exercises were performed during this time period. After six weeks from the surgery, active-assisted exercise including stick exercise to achieve full range of motion was performed. After 9 weeks from the surgery, Theraband exercise was initiated to strengthen repaired rotator cuff muscles. All patients underwent ultrasound at 24 months follow-up to evaluate integrity of supraspinatus tendon. The evaluation of integrity of supraspinatus tendon was performed and compared between two groups to evaluate the contribution of the subscapularis tendon to rotator cuff integrity. Re-tear of the supraspinatus was carefully evaluated through ultrasound by musculoskeletal radiologists who were experienced in ultrasound-diagnosis of shoulder more than 10 years.

Eligibility Criteria:
Inclusion Criteria:

* Full-thickness supraspinatus tear confirmed by preoperative MRI
* Willingness to be enrolled into the study and understanding the whole design of the study
* Patients who is undergoing arthroscopic surgery for rotator cuff repair

Exclusion Criteria:

* An irreparable massive rotator cuff tear which shows Stage-3 or 4 fatty infiltration inside the muscle of supraspinatus and subscapularis by MRI
* Cuff tear arthropathy
* Osteoarthritis with joint space narrowing or any joint spur identified in simple radiographs
* A Workers' compensation claim
* Major trauma or rotator cuff tear after shoulder dislocation
* Previous surgery or fracture on ipsilateral extremity
* Intact subscapularis tendon identified during arthroscopic surgery with 70 degrees arthroscope