Abstract
Background:
While reverse shoulder arthroplasty has shown successful outcomes for a variety of shoulder pathologies, postoperative instability continues to be one of the most common complications limiting outcomes. In the literature, reports of instability range from 2.4%–31%. Many authors recommend an initial attempt at closed reduction followed by a period of immobilization for management of the initial dislocation episode while others may seek to rule out infection or other secondary causes; however there is little data to support either practice. The purpose of this study was to evaluate the outcomes of patients with postoperative dislocation following reverse shoulder arthroplasty managed with closed reduction.
Methods:
A retrospective review of all reverse shoulder arthroplasties performed by a single surgeon (MF) from 2002-present was performed to identify all patients treated for postoperative dislocation treated with closed reduction, either in the office setting or under anesthesia in the operating room. A total of 21 patients were identified. Preoperative patient characteristics, implant selection, and time to initial dislocation episode were recorded. Final outcomes including recurrent instability need for revision surgery, ASES outcome score, and range of motion were evaluated.
Results:
There were 9 male and 12 female patients. Nearly 50% (10/21) cases had previous surgery, with the vast majority of these being previous arthroplasty (8/10). The average time to first dislocation was 200 days (range: 2 days–961 days), with 62% (13/21) occurring in the first 90 days. At average follow-up of 28 months following the dislocation episode, 62% of these shoulders remained stable (13/21). Six shoulders (29%) required revision surgery for recurrent instability. The revision procedure included a larger glenosphere and socket in all cases. All of these patients remained stable at final follow-up (Ave 25.5 months). In those cases successfully treated with closed reduction the average time to dislocation was 188 days, whereas the average time to initial dislocation in cases requiring revision surgery was 224 days (p = 0.82). All of these patients remained stable at final follow-up. Two shoulders (9%) remained unstable and either declined or were medically unfit to undergo revision surgery. The average ASES score in patients treated with closed reduction for instability was 68.0, and 62.7 for those treated with revision surgery (p = 0.64).
Conclusion:
This study shows that an initial dislocation episode following reverse shoulder arthroplasty can be successfully managed with closed reduction and temporary immobilization in over half of cases. The time to dislocation is not related to the likelihood of a successful closed reduction. Given that outcomes following revision surgery are not different from closed treatment we would continue to recommend an initial attempt at closed reduction in all cases of postoperative reverse shoulder arthroplasty dislocation.
