Revision of failed shoulder hemiarthroplasty to reverse total arthroplasty: analysis of 157 revision implants.

Background: There remains a paucity of studies examining the conversion of failed hemiarthroplasty (HA) to reverse total shoulder arthroplasty (RTSA). Therefore, the purpose of this study was to examine a large series of revision HA to RTSA.

Methods: A population of 157 patients who underwent conversion of a failed HA to a revision RTSA from 2006 through 2014 were included. The mean follow-up was 49 months (range, 24-121 months). The indications for revision surgery included instability with rotator cuff insufficiency (n = 127) and glenoid wear (n = 30); instability and glenoid wear were associated in 38 cases. Eight patients with infection underwent 2-stage reimplantation.

Results: Patients experienced significant improvements in their preoperative to postoperative pain and shoulder range of motion (P < .0001), with median American Shoulder and Elbow Surgeons and Simple Shoulder Test scores of 60 and 6 points, respectively. There were 11 (7%) repeated revision surgeries, secondary to glenoid component loosening (n = 3), instability (n = 3), humeral component disassembly (n = 2), humeral stem loosening (n = 1), and infection (n = 2). Implant survivorship was 95.5% at 2 years and 93.3% at 5 years. There were 4 reoperations including axillary nerve neurolysis (n = 2), heterotopic ossification removal (n = 1), and hardware removal for rupture of the metal cerclage for an acromial fracture (n = 1). At final follow-up, there were 5 "at-risk" glenoid components.

Conclusion: Patients experience satisfactory pain relief and recovery of reasonable shoulder function after revision RTSA from a failed HA. There was a relatively low revision rate, with glenoid loosening and instability being the most common causes.