Dissociation of the Glenosphere: A rare Post-operative Complication of Reverse shoulder Replacement

INTRODUCTION: Reverse shoulder replacement (RSR) has been accepted as the treatment of choice for glenohumeral arthritis with irreparable rotator cuff tear. Dislocation has been a potential complication of RSR but glenosphere disengagement is a rare complication itself. There have been only few published reports of this complication in the literature. CASE REPORT: In this case report, we have presented a case of repeated disengagement of glenoid sphere post-RSR in a 72-year-old male retired army personnel operated with Zimmer Biomet comprehensive RSR design. CONCLUSION: In our case scenario, we postulate that soft-tissue interposition was the reason for disengagement during first episode and was successfully relocated after removal. However, the subsequent disengagement was due to improper seating of sphere due to large central screw. Revision to a smaller central screw size appears to be the definitive solution in such case.