COMPARISON OF THE SIZE AND MORPHOLOGY OF UHMWPE WEAR DEBRIS PRODUCED BY A HIP-JOINT SIMULATOR UNDER SERUM AND WATER LUBRICATED CONDITIONS

This paper investigates the effect of lubricant on the size and morpho logy of ultra-high molecular weight polyethylene (UHMWPE) wear debris produced by a hip joint simulator. Bovine serum and water were chosen as the lubricants for comparison. When bovine serum was used as lubric ant, the majority of the wear debris produced was submicron sized and equiaxed or elongated in shape; no transfer film was found on the femo ral heads. When water was used as lubricant, large pieces of thin UHMW PE flakes about 2-3 mm across were produced and patches of transfer fi lms were observed on the femoral heads. These large flakes were compri sed of numerous smaller thin flakes compacted together. While the size and shape of the wear debris produced with serum lubrication are simi lar to those reported from clinical studies in total hip replacement, the debris produced with water lubrication bears no resemblance to wha t has been seen clinically.