Clinical outcome of wedged glenoid reconstruction in anatomic total shoulder arthroplasty for osteoarthritic retroverted glenoid: a minimum 2-year follow-up.

ABSTRACT

Background: Glenoid retroversion and humeral head subluxation is a progressive disorder due to abnormal force coupling and increased contact force. In situ placement of anatomic total shoulder arthroplasty (TSA) components in this scenario results in edge loading, progressive subluxation, and early failure. Wedged glenoid components have been demonstrated to improve glenohumeral alignment, but have not been correlated with mid-term clinical outcomes. Methods: Patients undergoing TSA using a wedged all-polyethylene glenoid component for retroverted glenoid deformity were identified from a prospectively maintained database. Preoperative planning computed tomography was routinely performed and compared to postoperative correction on radiographic evaluation. Evidence of loosening was correlated to prospectively collect clinical outcome using patient-reported outcome measures. A matched group of neutrally aligned glenohumeral joints undergoing anatomic TSA was used to compare improvement in clinical outcomes. Results: Over a 5-year period, 17 patients with mean age 60 (range 43-81, standard deviation 10.5) were identified with a mean preoperative neoglenoid retroversion of 16.7° (standard deviation 4.5). At a mean follow-up of 43.8 months (range 27-60), no revision surgeries were undertaken. Improvement in the Oxford Shoulder Score was 18 points (P < .0001). The mean improvement was compared to a matched control group demonstrating a comparable magnitude of improvement of 20.4 points. Conclusion: Wedged polyethylene components for Walch B2-type glenoids in TSA yield acceptable correction of the joint line, excellent clinical outcomes, and survivorship is maintained in the short term. The clinical and radiological outcome demonstrated similar improvement to that seen in A type deformities.