Humeral osteophyte size and clinical outcomes after anatomic total shoulder arthroplasty

Abstract

BackgroundThe severity of primary glenohumeral osteoarthritis (PGOA) has been associated with advanced radiographic findings including inferior humeral head osteophytes. The primary objective of this study is to analyze for any correlation between the size of the inferior humeral head osteophyte and functional outcomes in patients undergoing anatomic total shoulder arthroplasty (TSA) for PGOA. MethodsA retrospective review of a multi-surgeon database was performed to identify all patients with PGOA from 2015 to 2019 with a minimum of two-year clinical follow-up. Preoperative anteroposterior and Grashey views were used for all included patients to obtain measurements of the inferior humeral osteophyte. Two groups at the extremes of osteophyte width were identified: 1) patients with absent or minimal osteophytes (lowest quartile of width, < 4.9 mm) and those with large osteophytes (highest quartile of width, > 10.1 mm). Change in active range of motion (ROM) from baseline, patient-reported outcomes (PROs), strength and complications were assessed at a minimum of 2 years postoperatively and compared between the two groups. ResultsDemographics were similar for the large osteophyte group (n = 57) and small osteophyte group (n = 56). There was a higher percentage of patients with more significant glenoid deformity in the large osteophyte group compared to the small osteophyte group (P = .009 for A1 deltoid). The large osteophyte group had significantly more restricted preoperative ROM for all measures (P < .05 for all). There were no significant differences in final ROM achieved between the two groups. Patients in the large osteophyte group had greater improvement from baseline for external rotation at the side (31° vs 21°, P = .015), external rotation at 90° abduction (38° vs 20°, P = .004), and internal rotation at 90° abduction (30° vs 12°, P < .001) compared to the small osteophyte group. Overall, there were very few differences between the small and large osteophyte groups in final PROs, with the exception of a higher American Shoulder and Elbow Surgeons score in the large osteophyte group (90.8 vs 85.9, P = .048). ConclusionPatients with large humeral osteophytes have significantly greater restrictions in preoperative ROM compared to patients with small osteophytes. Patients with large osteophytes experience greater improvements in rotational motion after anatomic TSA compared to patients with small osteophytes, although the final ROM achieved was similar between groups. Overall, PROs after anatomic TSA were similar between patients with small and large osteophytes preoperatively.