Wrightington Hospital UHMWPE

This chapter focuses on the historical development of UHMWPE for use in hip replacemenfs by John Chamley. The main sources of this chapter have been Chamley s journal publications and books, as well as an outstanding biography of Chamley written by William Waugh (1990). Preparation of this chapter also entailed interviews and the review of archives and implants at Wrightington Hospital, DePuy International (Leeds), and the Thackray Museum of Leeds. 

The first UHMWPE hip comf>onents were fabricated either at the green lathe in his home workshop (the photo behind the lathe was taken of Chamley), or at the machine shop in Wrightington Hospital. 

UHMWPE has been used in knee replacements since the late 1960s, when Frank Gunston developed a cemented implant design at Wrightington Hospital [5, 6]. This early knee replacement resurfaced the individual condyles of the femur and the tibia. Total knee arthroplasty (TKA), which replaces the articulation between the femur and tibia, as well as between the femur and the patella, was developed in the 1970s, primarily at surgical centers in North America. The basic anatomical landmarks and implant features of a typical total knee replacement are illustrated in Figure 7.1. 

In May of that year, a salesman (Mr. V.C. Birms) arrived at Wrightington and was introduced to Craven by the hospital s supply officer. Binn s products, small gears and bushings, were fabricated from UHMWPE and he provided Craven with a sample of the material. Chamley s first reaction to UHMWPE is described in his biography as follows "When shown tire material, Chamley dug his thumb-nail into it and walked out, telling Craven he was wasting his time" (Waugh 1990). 

Because the sterilization of UHMWPE continues to be a controversial topic, even today, it is helpful to review the early methods in use at Wrightington for joint replacement components. The stainless steel femoral components were produced by Thackray [17]. Prior to 1968, only the final polishing of the femoral heads would be performed at Wrightington. After 1968, the stems were fabricated entirely by Thackray. The femoral components were provided nonsterile by Thackray and sterilized at the hospital by autoclaving. This sterilization method was not appropriate for UHMWPE, which would distort after prolonged steam exposure. 

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