A “Floating Glenoid” after a Reverse Total Shoulder Arthroplasty: A Case Report with Literature Review

Abstract
A shoulder replacement for cuff tear arthropathy was the original indication of the reverse total shoulder arthroplasty (rTSA). However, over time, this particular concept of shoulder arthroplasty has found new indications for other pathologies such as complex proximal humeral fractures and irreparable rotator cuff tears with rotator cuff arthropathy. Retensioning of the deltoid muscle is a vital step during this procedure in order to restore active elevation however, this can be potentially problematic since it results in anatomical changes and often times increases the stress forces across the acromion. We experienced a rare case of an 84-year-old female presenting with an extensive fracture resulting in a “floating glenoid” after reverse total shoulder arthroplasty via a deltopectoral approach. In our case, the patient presented with gradual onset pain in the posterior shoulder with point tenderness over the acromion, which worsened during active joint movement. The patient was definitively managed with surgical removal of the glenoid implants and conversion to a hemiarthroplasty. While there are existing strategies for preventing fractures of this nature, further research is still necessary to establish best management guidelines of these fracture complications associated with rTSA in order to achieve optimal outcomes.