Review Question - QID 220132

A reverse total shoulder arthroplasty (RTSA) would give the patient the most reliable outcome in terms of long-term overhead function and restores motion by lengthening the deltoid lever arm (Answer choice 3).

RTSA restores overhead function in patients with massive, irreparable rotator cuff tears by altering shoulder biomechanics. The prosthesis shifts the center of rotation (COR) medially and inferiorly by using a convex glenoid and concave humeral component, which reduces shear forces and increases the mechanical advantage of the deltoid. Translation of the COR places the deltoid under greater tension, enhancing its ability to generate torque and effectively substituting for the absent supraspinatus in arm elevation.

RTSA has demonstrated superior long-term survivorship compared to other surgical options for irreparable rotator cuff tears, such as tendon transfers, partial rotator cuff repairs, and superior capsular reconstruction. Studies report RTSA implant survival rates of approximately 90–95% at 10 years, whereas alternative procedures often show higher failure or revision rates over time. Tendon transfers, such as lower trapezius or latissimus dorsi transfer, can restore function but may not provide lasting pain relief and have variable success rates, particularly in elderly patients. Similarly, superior capsular reconstruction has shown promising short-term outcomes, but lacks long-term data and can be associated with graft failure. Partial repairs may offer symptom relief, but often do not restore full shoulder function. Given its predictable pain relief, functional improvement, and high survivorship, RTSA is considered the gold standard for managing irreparable rotator cuff tears in patients with significant shoulder dysfunction.

Mori et al. investigated the impact of infraspinatus fatty degeneration on the outcomes of arthroscopic fascia lata autograft patch procedures for large to massive rotator cuff tears. They found that patients with low-grade fatty degeneration (Goutallier stage 1 or 2) of the infraspinatus had a higher rate of intact repairs (73.1%) compared to those with high-grade degeneration (stage 3 or 4), who had a significantly lower rate (10.6%). Although clinical scores, range of motion, and muscle strength improved in both groups, the improvements were more pronounced in patients with low-grade degeneration, leading the authors to conclude that the procedure is less beneficial for cases with advanced fatty degeneration of the infraspinatus.

Mihata et al. evaluated the effectiveness of arthroscopic superior capsule reconstruction (SCR) using fascia lata autografts in 24 patients with irreparable rotator cuff tears. The results demonstrated significant improvements in shoulder function, with mean active elevation increasing from 84° preoperatively to 148° postoperatively, and the American Shoulder and Elbow Surgeons (ASES) score rising from 23.5 to 92.9 points. Additionally, postoperative imaging showed an increase in the acromiohumeral distance from 4.6 mm to 8.7 mm, indicating restoration of superior stability in the glenohumeral joint. However, 4 of 23 patients were noted to have a retear at mean 34-month follow-up, 3 of which had a severe Goutallier stage of the infraspinatus on preoperative MRI.

Figure 1 demonstrates a T1-weighted MRI demonstrating severe fatty atrophy of the supraspinatus and infraspinatus.

Incorrect answers:
Answer 1: Acellular dermal allograft to augment rotator cuff healing is less reliable than an RTSA in elderly patients due to the risk of retear.
Answer 2: Acellular dermal matrix fixed from the glenoid to the humerus to maintain humeral head depression describes a superior capsular reconstruction, which has less reliable outcomes than an RTSA, particularly in older patients.
Answer 4: A partial rotator cuff repair is not a lasting solution to a massive retracted rotator cuff tear and will not restore function once there is significant atrophy.
Answer 5: A trapezius transfer is an option for irreparable superior rotator cuff tears; however, its results are less reliable than an RTSA.