Total shoulder arthroplasty with an all-polyethylene pegged bone-ingrowth glenoid component: a clinical and radiographic outcome study.

BACKGROUND: Loosening of the glenoid component continues to be the foremost cause of medium and long-term failure of shoulder replacements. The purpose of this study was to evaluate the clinical and radiographic results of a minimally cemented all-polyethylene pegged glenoid component designed for biologic fixation.
METHODS: Forty-four shoulders in forty-one patients with a mean age of sixty-six years underwent total shoulder arthroplasty with a pegged bone-ingrowth glenoid component. Outcome data included the American Shoulder and Elbow Surgeons questionnaire, the Simple Shoulder Test, and visual analog scales. A detailed radiographic analysis was performed by two board-certified musculoskeletal radiologists who were blinded to clinical and patient-reported outcomes. The radiographs were evaluated with regard to the presence of radiolucent lines at the bone-cement interface, implant seating, and the radiodensity between the flanges of the central peg.
RESULTS: The mean duration of clinical follow-up was four years and the mean duration of radiographic follow-up was three years. Twenty shoulders had perfect seating and radiolucency grades, thirty had increased radiodensity between the flanges of the central peg, and three demonstrated osteolysis. Radiodensity about the uncemented central peg at the time of the latest follow-up was positively associated with perfect seating and radiolucency grades on the initial postoperative radiographs (p = 0.03, Fisher exact test). The Simple Shoulder Test score, the American Shoulder and Elbow Surgeons score, and all visual analog scale scores had improved significantly (p < 0.01) at the time of the latest follow-up.
CONCLUSIONS: Total shoulder arthroplasty with a minimally cemented, all-polyethylene, pegged glenoid implant can yield stable and durable fixation at short to medium-term follow-up (mean, four years).