Instability and dislocations after reverse total shoulder (RTSA) remain among the most common complications of reverse total shoulder. The authors of Instability after reverse total shoulder arthroplasty: risk factors and how to avoid them conducted a study of 103 RTSAs (97 primary, 6 revision). Among these 103 RTSAs, 6 patients had 5 dislocations (3 in primary RTSAs, 3 in revision RTSAs). One dislocation occurred immediately after surgery, 3 from low-energy mechanisms of injury, and 2 without known inciting events. All dislocations were treated in the operating room; no dislocation was successfully treated with simple closed reduction in the clinic. They found that the risk of dislocation is higher for patients with fractures and post fracture deformity, for patients with higher BMI and for patients undergoing revision surgery.

The authors suggest that in patients with persistent instability or with risk factors for instability, consideration should be given for use of larger glenospheres, increasing the lateral offset, minimizing retroversion, performing peri-glenoid releases and optimizing the tension of the soft tissues.

Comment: Our colleagues from Spain have provided a nice summary of their experience. The case examples shown below are educational.