Implant Retrieval Analysis of Bilateral Hip Resurfacings Obtained at Autopsy: A Case Report.

Abstract

Hip resurfacing arthroplasty with use of metal-on-metal bearings and hybrid fixation (femoral cement and acetabular porous ingrowth) has been in clinical use for more than a decade. Although femoral neck fracture1,2, femoral or acetabular loosening3, and soft-tissue masses associated with high wear4,5 are known failure modes, long-term clinical results in men generally have been reported to be good6,7. Many metal-on-metal hip resurfacing arthroplasty failures occur within the first one or two years postoperatively, and there have been few long-term specimens available for analysis. This paper describes the analysis of bilateral hip resurfacings from a patient who donated the components as part of a Willed Joint Program at the senior author’s (H.C.A.) institution. A fifty-seven-year-old man with a history of Legg-Calve-Perthes disease, diagnosed at age seven and treated at age ten with several months of traction, had presented with bilateral osteoarthritis of the hip joints. A hip radiograph had revealed broad, flat femoral heads with markedly shortened necks and incongruent acetabula (Fig. 1). The patient had received a 52-mm CONSERVE PLUS (Wright Medical Technology, Arlington, Tennessee) femoral component along with a 62-mm CONSERVE PLUS acetabular component on the left side; four months later, he had received a 48-mm CONSERVE PLUS femoral component and a 58-mm CONSERVE PLUS acetabular component on the right side. The surgical technique has been detailed previously8. Specifically, the “second-generation femoral fixation” technique had been used, which included the use of a high-speed burr to remove cystic tissue, drilling an increased number of femoral dome and chamfer holes, suction to clean the bone, and cement to secure the stem. The prepared femoral heads are shown in Figure 2, and the implanted hips are shown in Figure 3. Postoperatively, the patient had …