Abstract
The PFC Sigma Cobalt Chrome Sigma (PFCSCC) was introduced in 2006, an update of the PFC Sigma designed to reduce backside wear. To help identify any significant early failures following its introduction, we prospectively identified all recipients over a one-year period. The patient's clinical, demographic and radiographic data, American Knee Society scores (AKSS), Oxford Knee scores (OKS) and SF-12 scores was recorded pre-operatively and at one, three and five years. 233 patients underwent 249 primary knee arthroplasties with the PFCSCC. Seventeen patients (19 knees) died and 29 patients (30 knees) were also lost to follow up at the five year point. The mean age was 66.6 (34–80) with 47.6% of the cohort being male. The mean five year follow-up was 1836 days (1530–2307). Five knees (2.2%) were revised for infection and three were revised for pain. The 5–year cumulative survival rate was 96.6% for any failure and 98.6% for aseptic failure. AKSS 32.6 (0–86.6) preoperatively, 80.7 (29–95) 5 years P < 0.001. OKS was 39.0 (22–53) preoperatively, 23.5 (4.7–42.3) 5 years P < 0.001. These results demonstrate a good early survivorship when compared to the old design PFC Sigma, however further follow-up to ten years is required.
