Mid- to long-term outcomes of a cemented, all-polyethylene pegged glenoid component in anatomic total shoulder arthroplasty.

Abstract

The primary aim of this study was to evaluate mid- to long-term survival of an all-polyethylene pegged glenoid component used in anatomic total shoulder arthroplasty (TSA). The secondary aim was to review clinical and radiologic outcomes. A retrospective analysis of a prospectively collected local arthroplasty register of consecutive patients undergoing TSA with an all-polyethylene pegged glenoid between January 2009 and December 2018 was undertaken. In total, 108 TSAs using this implant were performed in our unit in 98 patients (18 men and 80 women), with 10 patients undergoing bilateral TSA. The mean age at the time of the operation was 71.3 years (range, 44-87 years). The mean follow-up period was 5.1 years (range, 2-10.6 years). In addition to survival analysis, clinical evaluation included the postoperative Oxford Shoulder Score, Constant score, and visual analog scale (VAS) pain score, as well as range-of-motion assessment. Radiologic outcomes included an assessment of radiolucency based on the Lazarus grade. Kaplan-Meier survival analysis revealed a 6-year survival estimate of 94.1% for all-cause revision. Revision was required in 6 patients: 4 for cuff failure and 2 for instability. At follow-up, the mean Oxford Shoulder Score was 38.2 (standard deviation [SD], 12.3); mean Constant score, 59.3 (SD, 17.0); and mean VAS pain score, 1.8 (SD, 2.5). Mean forward elevation at final follow-up was 111⁰ (SD, 26.6⁰); mean abduction, 102⁰ (SD, 34.0⁰). Clinical outcomes were maintained at long-term follow-up (>8 years), with the exception of the VAS pain score, which increased by 2.1 points (P=.034). Radiologic assessment revealed that 28 patients had radiolucency consistent with Lazarus grade ≥ 3 with clinical outcomes not being affected. Mid- to long-term follow-up indicates a low revision rate and good clinical survivorship for cemented, all-polyethylene glenoid components. No patients, so far, have undergone revision for glenoid loosening, but radiographic follow-up has shown that 36% of these implants have signs of radiolucency. Further follow-up is required to determine longer-term survivorship.