We present an independent multi-centre follow-up of metal-metal resurfacing from district regional hospitals (DGHs) in a series of ‘young’ patients with implants from a single manufacturer. Between November 1995 and November 2002, two hundred and thirteen primary total hip resurfacings were performed in six centres. Two hundred and ten patients were followed up with none lost to follow-up. The average age of the patient group was 52.9 years range (21.9–71.3 years). Of these 210 patients 119 were male and 91 were female. There were three bilaterals and five revisions recorded with a revision rate of 2.3% at seven years. The maximum duration of follow-up was 84 months, the minimum was 3 months and the mean follow-up was 43.5 months. The average Harris Hip score at the latest follow-up review was 78.15 (range 23–100). The Kaplan-Meier Survivorship of Cormet was 95% at 7 years and a survivorship of 97.38% at three years. These results indicate that metal-metal resurfacing meets the NICE guidelines for suvivorship at the three year benchmark in DGHs with local patients and is on course to meet the 10 year benchmark despite the extremely demanding patient group.
Meniscal knee designs are unlike conventional surface replacement designs as they have two moving surfaces between the polyethylene and the metal tibial tray. This means the sliding distance is shared over two surfaces. This study was performed to assess the damage to both surfaces and whether the concept of wear sharing exists in knee prostheses of these designs. Although 22 meniscal bearings from both the designs of knee prosthesis of the Minns design were collected, 4 pairs of bearings (2 from each design of the Minns knee) were examined in detail as it was felt they represented the range of damage features seen in the explanted samples. These samples were examined for wear and damage on both the upper and lower polyethylene surfaces. In both designs of bearings, the wear was significantly less extensive on all the lower surfaces examined. The roughness of the burnished areas on the upper surface was always less than any of the lower surfaces of the same bearing. Even the specimens with gross wear and delamination damage on the upper surface has no corresponding damage on the lower surface. Only one specimen had wear on the lower surface of the dovetail retention bar, usually no wear was seen on this surface indicating the main weight-bearing area is the lower flat surface of both designs of bearings, and that the sliding distance is shared during use thus reducing the wear factor for both surfaces in use.