Abstract
Xenografts of bovine bone were used successfully for years with a minimum acceptable rate of side effects in total hip revision arthroplasty for filling large bone defects. The great majority of them was withdrawn from the market when any biological product of bovine origin was considered as a potential carrier of prions infection. However, current EEC regulations permit their surgical therapeutic use if obtained from cattle under 6 months of age, which are supposed to be not at risk of prion transmission. Lubboc, a purified trabecular bone matrix containing only type-1 collagen and hydroxyapatite, fulfils this requirement. From 2001 to 2003 we used this product in fragments (chips) to fill bone defects of the acetabulum before screwing the acetabular rings in 37 patients. No massive grafts were implanted. Minimum follow-up was 12 months, maximum 27 months. Four subjects were lost to follow-up. The fate of the grafts was evaluated for evidence of union, remodelling, resorption, migration of the rings or fracture of the newly formed bone. No significant adverse events were registered. If the risk of transmitting infectious agents is excluded or minimised according to the present legislation, it seems unjustified to remove xenografts from the options available to orthopaedic surgeons, considering the problems of bone stock deficiency and reconstruction in hip arthroplasty revision surgery.
