This retrospective case series reviews instability among the first 57 reverse total shoulder arthroplasties at a single institution. It characterizes the preoperative, intraoperative, and postoperative factors behind 9 unstable shoulders. The goal is to build a workup and treatment framework for this difficult complication.
When a reverse shoulder dislocates early, do not assume it is a simple soft-tissue problem. This series ties instability to four modifiable culprits: inadequate soft tissue, poor deltoid tension, malpositioned implants, and infection. The first move in any unstable reverse workup is to rule out infection. P acnes is indolent, so hold cultures at least 10 days before calling it clean.
Once infection is excluded, distinguish the two noninfectious mechanisms. Global decoaptation (low deltoid tension) is fixed by increasing offset. Component impingement on the inferior scapular neck requires baseplate and glenosphere revision.
The sobering lesson is prognostic: only 3 of 9 shoulders ended concentrically reduced despite revision. That poor salvage rate is the argument for getting subscapularis handling and glenoid positioning right at the index case.
This retrospective case series reviews instability among the first 57 reverse total shoulder arthroplasties at a single institution. It characterizes the preoperative, intraoperative, and postoperative factors behind 9 unstable shoulders. The goal is to build a workup and treatment framework for this difficult complication.
When a reverse shoulder dislocates early, do not assume it is a simple soft-tissue problem. This series ties instability to four modifiable culprits: inadequate soft tissue, poor deltoid tension, malpositioned implants, and infection. The first move in any unstable reverse workup is to rule out infection. P acnes is indolent, so hold cultures at least 10 days before calling it clean.
Once infection is excluded, distinguish the two noninfectious mechanisms. Global decoaptation (low deltoid tension) is fixed by increasing offset. Component impingement on the inferior scapular neck requires baseplate and glenosphere revision.
The sobering lesson is prognostic: only 3 of 9 shoulders ended concentrically reduced despite revision. That poor salvage rate is the argument for getting subscapularis handling and glenoid positioning right at the index case.