Reverse Shoulder Arthroplasty for Post-Capsulorrhaphy Arthropathy Results in Similar Clinical Outcomes Compared to Glenohumeral Osteoarthritis.

Abstract

Background: Reverse shoulder arthroplasty (rTSA) is a reliable treatment option for various indications, including glenohumeral osteoarthritis (GHOA) with an intact rotator cuff. Following either open or arthroscopic instability surgery, a certain portion of patients develop post-capsulorrhaphy arthropathy (PCA) and ultimately need shoulder replacement. While these patients often have an intact rotator cuff, alterations to the native soft tissue anatomy may compromise the success of anatomic total shoulder arthroplasty (aTSA), leading some to consider rTSA. Limited literature currently exists evaluating the outcomes of rTSA as a treatment for PCA.

Methods: Patients undergoing rTSA for the treatment of GHOA or PCA were retrospectively propensity score-matched in a 2.2:1 ratio based on age, sex, and BMI, as well as preoperative American Shoulder and Elbow Surgeons (ASES) score, forward elevation, and external rotation. Preoperative clinical outcomes at a minimum 2-years consisted of the Visual Analog Scale (VAS) for pain, Single Assessment Numeric Evaluation (SANE) score, and ASES score, as well as active forward elevation, internal rotation, and external rotation. The PCA cohort was stratified into sub-cohorts based on capsulorrhaphy technique (open or arthroscopic), all of which were soft tissue procedures. Univariate analysis was performed to compare cohort and sub-cohort demographics, clinical outcomes, and glenoid erosion patterns using the Walch classification system.

Results: After matching, the GHOA and PCA cohorts consisted of 82 and 37 patients, respectively, with no significant differences in age (GHOA 68±6 years versus PCA 66±6 years; P=.082) or follow-up duration (GHOA 29±12 months versus PCA 29±11 months; P=.493). Both groups demonstrated significant improvement in all clinical outcome metrics. The arthroscopic and open PCA sub-cohorts consisted of 19 and 18 patients, respectively. No significant preoperative or postoperative clinical outcome differences were observed between any cohort or sub-cohort studied (P>.05). There was a significant difference in Walch classification distribution between the GHOA and PCA cohorts (P=.014), with the most likely cause being a difference in frequency of A1 (GHOA 25.9% versus PCA 36.3%) and B3 (GHOA 24.7% versus PCA 12.1%) glenoid wear patterns.

Conclusion: This study demonstrates that rTSA is a reliable and effective treatment option for patients with PCA. Furthermore, the surgical technique of the previous soft tissue instability procedure (arthroscopic versus open) does not affect clinical outcomes after rTSA. Given the predictability of the outcomes associated with rTSA for PCA, consideration should be given for this as a treatment choice.

Level of evidence: Level III; Retrospective Cohort Comparison; Prognosis Study.