A single surgeon’s experience of metal-on-metal hip resurfacing arthroplasty in a district general hospital: 9-year clinical results using the Conserve Plus resurfacing system

Abstract

Background: A number of hip resurfacing arthroplasty implants have been found to have satisfactory clinical outcomes, suggesting implant design has a significant role. The aim of our study was to report the radiographic and clinical outcomes of a series of Conserve Plus hip resurfacing arthroplasty performed by a single surgeon. Methods: Our series included 51 consecutive resurfacings at mean follow-up of 7.61 yr performed through a modified Hardinge approach. Postoperatively, functional scores, ion levels, and hip radiographs were obtained at 6-8 wk, 6 mo, 1 yr, and yearly thereafter. Results: There were statistically significant improvements in University of California, Los Angeles Activity Score (UCLA), Oxford Hip Score (OHS), and Harris Hip Score (HHS), at 1 yr, with no further significant changes in functional scores identified at time of last review. Initial median postoperative cobalt and chromium levels were 1.06 and 1.77 μgl−1, with no significant increases at the time of last review. There were no significant differences in radiographic outcomes at the time of last review compared with early postoperative radiographs. Two implants required revision to THA. Kaplan-Meier analysis with revision as an endpoint found survivorship of 96% at up to 9.5 yr. Conclusions: This study found satisfactory survivorship and clinical outcomes with the Conserve Plus, and to our knowledge this is the largest series to date using the modified Hardinge approach.