A large taper mismatch is one of the key factors behind high wear rates and failure at the taper junction of total hip replacements: A finite element wear analysis.

摘要: Abstract Total hip replacement (THR) is one of the most successful orthopaedic surgeries; however, failures can occur due to adverse reactions wear debris. Recently, a large number linked release metal particles from taper junction between femoral head and stem have been reported. One possible reason for this may be design variations such as mismatches associated with trunnion angles. Could mismatch lead inappropriate contact mechanics increase relative micromotion thus wear? In study, 3D finite element (FE) models commercial THR perfectly matched interface algorithm were used investigate extent that could at identify optimum tolerances in order reduce wear. A co-ordinate measuring machine (CMM) was analyse depth volumetric rate tapers 54 explanted 36 mm diameter Cobalt Chromium heads, which had service 5.1 years average, validate FE analyses. It found (e.g. 9.12´) results high (2.960 mm3 per million load cycles). Such rates major negative effect on clinical outcomes these implants. also even slight reduction significantly reduced magnitude (0.069 mm3 cycles average 6´ mismatch). recommended cone angles should manufactured produce less than junction.