Ten-year results for a single-surgeon series of Scorpio non-restrictive geometry (NRG) posterior stabilised (PS) total knee replacement.

Abstract

To report the long-term results for a single-surgeon consecutive series of Scorpio non-restrictive geometry (NRG) posterior stabilised (PS) total knee replacement (TKR). Forty-six consecutive patients who underwent 53 Scorpio NRG PS were identified. Change in range of motion (ROM) and Oxford Knee Score (OKS) over time were recorded. Radiographs were evaluated for alignment and radiolucent lines. Survival analysis for the prosthesis was calculated. At a mean of 10.1 years (range 9.1-10.9) following exclusions thirty-seven (69.8%) knees in thirty-one (67.4%) patients (6 bilateral) were available for review. None of the patients required revision surgery. Mean OKS score at 10 years was 37.8. The mean ROM significantly improved from 95° pre-operative to 117.5° at 5 years and 115° at 10 years (p = < 0.001). This equates to a value-added range of motion (VAROM) of 19° at 5 years and 15.6° at 10 years. There was a correlation between OKS and VAROM at 5 and 10 years. Radiological assessment did not reveal any evidence of progressive cement radiolucent lines nor component migration. In this series the Scorpio NRG PS showed 100% 10-year survivorship. We found a significant improvement in ROM and VAROM over time. This was not associated with increased signs of loosening.