Hemiarthroplasty for nontraumatic avascular necrosis of the humeral head is associated with low complications and reoperation rates

Abstract

BackgroundThe objective of this study was to retrospectively review clinical and radiographic outcomes of patients who had undergone hemiarthroplasty for nontraumatic avascular necrosis (AVN) of the humeral head and to review demographic and clinical factors that might affect patient outcomes. MethodsThe patient sample for this study was identified through our institutional Total Joint Registry Database. Between 2009 and 2019, 68 hemiarthroplasties had been performed for nontraumatic AVN. There were 44 (64.7%) female and 24 (35.3%) male patients, with a mean age of 44.3 (range 17-78) years. The average follow-up time was 6.5 years, with a minimum of 2.1 years. There were 34 patients (50%) with an identifiable underlying etiology of steroid and/or chemotherapy use, 17 (25%) were considered idiopathic, 9 (13.2%) with a hematologic or coagulopathic condition, 6 (8.8%) with radiation, and 2 (2.9%) with a history of alcohol abuse. Outcomes, including revision surgeries, reoperations, and complications, were recorded. Range of motion (ROM) data and functional outcome scores, including the American Shoulder and Elbow Surgeons score, Simple Shoulder Test score, and patients’ subjective level of satisfaction with the operation, were evaluated. Preoperative radiographs were reviewed, and the degree of AVN was classified. Most recent postoperative radiographs were reviewed to assess for stem loosening, humeral head subluxation, and glenoid erosion. ResultsPostoperative American Shoulder and Elbow Surgeons scores were 74.5, and Simple Shoulder Test scores were 75.3. Overall satisfaction with the operation was rated as 7.3 on a scale of 0-10. The average external rotation was 62 degrees, and the average active elevation was 163 degrees. No differences in outcomes scores or ROM were noted based on preoperative etiology, although the idiopathic group trended toward lower forward flexion compared to the steroid/chemotherapy group. Three of 68 (4.4%) patients suffered postoperative complications. The overall revision rate was 2/68 (2.9%), both involving conversion to anatomic total shoulder arthroplasty for progressive painful glenoid erosion. Radiographically, no patients had evidence of loosening. One patient (2.2%) had mild subluxation, 2 had moderate subluxation (4.4%), and 1 had severe subluxation (2.2%) of the humeral implant. Three patients had mild (6.7%), 4 had moderate (8.9%), and 3 had severe (6.7%) glenoid erosion. ConclusionHemiarthroplasty for nontraumatic AVN of the humeral head provides satisfactory functional outcomes and ROM, with low complication and revision rates. These outcomes and revision rates appear to be better than those reported in the literature for posttraumatic AVN. Hemiarthroplasty may lead to radiographic evidence of glenoid erosion, but this is well tolerated and does not appear to lead to substantially high revision rates, at least in the intermediate-term follow-up.