Abstract
Introduction:
One reason that young and active patients choose hip resurfacing arthroplasty (HRA) rather than stemmed total hip arthroplasty (THA) is that they wish to return to high impact sports after their operation. Few studies have addressed the outcome in hip arthroplasty patients who choose to participate in high impact sports post-operatively. We therefore wanted to determine if the durability of HRA in highly active patients was decreased.
Methods:
From 5/2001 to 5/2011, a single surgeon performed 2434 HRA cases in 2013 patients. The study group consists of all patients that had a UCLA Activity score of 9 or 10 at any point after surgery in our prospective database. There were 936 (38%) cases in 776 patients who reported participating in high impact sports at some point after surgery. This group was compared to the entire database. The mean age of the study group was 50 ± 8 years, which was significantly younger than the entire group (P = 0.0007). 82% of the study group was male compared to 73% in the entire group (P < 0.0001). 85% of the primary diagnoses were osteoarthritis in the study group compared to 78% in the entire group (P < 0.0001), followed by dysplasia (8%) and osteonecrosis (4%).
Results:
For the study group, the average follow-up length was 4 ± 2 years. 389 (42%) cases had at least 5 years follow-up. 10 (1%) revisions were identified: five (0.5%) due to femoral component loosening; two (0.2%) due to adverse wear; two (0.2%) for acetabular component loosening; one (0.1%) for acetabular fracture. There was no difference in the failure rate due to any specific complication type. The Kaplan-Meier survivorship rate was 99.5% at 5 years and 95.8% at 10 years, which compared to 96.9% at 5 years and 91.6 at 10 years for the entire group. 61 cases had the acetabular inclination angles >50°; 2 of which were revised for adverse wear related failures. Metal ion test results were available for 52% cases in the study group. Metal ion levels were ≥7 μg/L in 18 (1.9%) cases and ≥10 μg/L in 11 (1.2%). Excluding the failed cases, the average Harris hip scores were 99 ± 3 for the study group which was significantly better than the entire group (P < 0.0001).
Discussion:
When compared to the entire database, hip resurfacing patients that participate in high impact sports after surgery have a significantly higher HHS; they have a similar 10-year survivorship of 95.8%; they have a similar low adverse wear failure rate of 0.2%. We therefore conclude that a patient's activity level has little effect on the 10 year outcome of HRA and that restrictions are therefore not necessary after hip resurfacing.
