76 – GREATER THAN 20-YEAR FOLLOW-UP STUDY OF THE CEMENTLESS POROUS COATED ANATOMIC (PCA) TOTAL HIP ARTHROPLASTY

Abstract

Purpose: The purpose of this study was to determine the greater than 20 year survivorship of the PCA total hip arthroplasty (THA) in patients with severe hip osteoarthritis.

Method: A prospective follow-up of 315 consecutive patients treated with a PCA cementless THA in patients with hip osteoarthritis was performed. Patients had postoperative assessments and radiographs every two years. Overall THA, femoral stem and acetabular cup revisions and Kaplan-Meier survivorship was determined. Revision rates and survivorship was also investigated across gender.

Results: The mean age of our patients was 61 years old (range 20 to 86) with 47% female patients. 226 cases used a 26mm articulation and 89 cases a 32mm articulation. At 23 years follow-up, 188(60%) patients were alive with retained implants while 85(27%) were deceased with still implants that were functioning well. Forty-two cases (13%) were revised (30 sockets, 13 stems), five of which later deceased. The 20 year Kaplan Meier survivorship for the overall THA, stem component and acetabular cup were 86%, 97% and 90% respectively. Survivorship of the acetabular cup for 26mm and 32mm articulations was 92% and 85% respectively (p=0.016). Females had a worse THA survivorship than males, 82% and 91% respectively (p=0.036).

Conclusion: The PCA cementless THA has performed well beyond 20 years with 26 mm articulations doing better than 32 mm, and male gender associated with better outcomes. The authors postulate that polyethylene thickness is key to predicting failure.