Minimum 48-month Clinical and Radiographic Outcomes of Anatomic Total Shoulder Arthroplasty With a Partially Cemented All-polyethylene Fluted Central Peg Glenoid Component.

Abstract

Partially cemented all-polyethylene glenoids with press-fit fluted central peg (FCP) fixation are commonly used for anatomic total shoulder arthroplasty (aTSA). The purpose of this study was to evaluate clinical outcomes and radiographic findings in patients with ≥48-month follow-up after aTSA with one FCP glenoid design. A prospective patient registry was used to identify a consecutive group of patients who had undergone aTSA using a FCP glenoid and had ≥48-month follow-up. Final postoperative radiographs, as well as short-term if available, were assessed by five shoulder specialists for bony incorporation and/or radiolucency about the FCP using a validated discriminatory method of evaluating native glenoid reaction to the FCP. Changes in patient-reported and clinical outcomes were evaluated, and regression analysis was performed to identify predictors of central peg osteolysis (CPO), poor clinical outcome, or revision. Eighty-three shoulders satisfied inclusion criteria. At final follow-up (average 90 months), notable improvements were noted in all outcomes (P < 0.05), including a 75% satisfaction rate. On final imaging, 16 patients (19%) demonstrated optimal FCP bony ingrowth, and 23 (28%) demonstrated CPO. The radiographic appearance of bone around the central peg tended to deteriorate over time and trended with worsened clinical outcomes, but these differences were not notable. Of 73 patients with short-term and final imaging, progression of radiolucency was observed in 30 (41%) and associated with less improvement in American Shoulder and Elbow Surgeons score (P = 0.026) and Single Assessment Numeric Evaluation (P = 0.022) scores. Risk of revision was 13% greater in patients with CPO on final imaging while increased age was associated a lower risk of revision. Clinical improvement was observed in most of the patients, but with a dissatisfaction rate of 25%. Progression of CPO was associated with lower improvement in final American Shoulder and Elbow Surgeons score and Single Assessment Numeric Evaluation scores and a higher probability of revision. Level IV Case Series.