Prospective assessment of osteoporosis in total shoulder arthroplasty

Abstract

HypothesisThe risks of shoulder arthroplasty in those with osteopenia and osteoporosis are not fully understood. The purpose of this study was to prospectively evaluate intraoperative complications in those undergoing shoulder arthroplasty with low bone mineral density (BMD). MethodsWe prospectively enrolled consecutive patients undergoing shoulder arthroplasty with a preoperative computed tomography (CT) scan from January to July 2021. Exclusion criteria included age <50 years, revision surgery, fracture, diagnosis of inflammatory arthropathy, or active infection. An intraoperative survey assessing bone quality and complications was collected. A blinded reviewer then measured bone quality based on preoperative CT scan using a previously validated method. Subjects were then divided between normal and low BMD groups with low BMD including both osteopenia and osteoporosis. ResultsWe enrolled 75 consecutive patients who met all inclusion criteria. Nine patients were excluded due to incomplete imaging leaving a final cohort of 66 patients. The average age was 69.2 years (50.4-88.5 years), with 41 males (62.1%) and 25 females (37.9%). There were 33 anatomic total shoulder arthroplasties and 33 reverse shoulder arthroplasties. Surgeons were very accurate in identifying normal bone intraoperatively (95.5% correct) but less accurate in identifying poor bone quality (45.5% correct). Surgeons reported making changes to their plan or technique in 8 cases (12%), with 7 (87.5%) of these changes occurring in those with poor bone quality. The lesser tuberosity was damaged with posterior retraction in 16 cases (24.2%), with 13 (81.3%) of those being in patients with poor bone quality. There was 1 intraoperative glenoid rim fracture, which occurred in a patient with low bone density. ConclusionThe prevalence of osteoporosis in the population undergoing shoulder arthroplasty is high. Performing shoulder arthroplasty on those with poor bone quality presents multiple challenges, which are underappreciated. Being able to better predict bone quality based on preoperative CT imaging can alert the surgeon to potential intraoperative complications.