Yahia Chabane Ait, Diwanji Sanket, Ganapati Muthu, Vendittoli Pascal-André, Lavigne Martin
Research Centre of Maisonneuve, Maissonnueve Rosemont Hospital, 5415 Assomption Boulevard, Montreal, Quebec, Canada.
Hip Int. 2011 Jul-Aug;21(4):468-74. doi: 10.5301/HIP.2011.8573.
Implantation of a cementless press-fit acetabular cup during hip arthroplasty alters stress transfer to the periacetabular bone, resulting in stress shielding of cancellous bone and enhanced load transfer to cortical bone. Theoretically, the thicker, stiffer and larger acetabular cup of a hip resurfacing may increase periacetabular bone stress shielding. We attempted to assess the matter (at a minimum of 2 years after surgery) by measuring any difference in supra acetabular bone mineral density (BMD) between the side implanted with a thick monoblock cobalt-chromium (Co-Cr) acetabular component during hip resurfacing (HR) and the opposite non-operated side. We retrospectively recruited 44 patients who had undergone metal-on-metal hybrid hip resurfacing for unilateral osteoarthritis of the hip joint . BMD of the supra acetabular bone of both hips was measured using a dual energy X-ray absorptiometry (DEXA) scan. The BMD measured in Zone 2 was not different on the operated side (1.69 g/cm2 ± 0.48) compared with the non-operated side (1.70 g/cm2 ±0.49) (p=0.904). Contrary to our expectations, implantation of a monoblock Co-Cr acetabular component during HR did not cause significant stress-shielding of supra acetabular cancellous bone.
髋关节置换术中植入非骨水泥压配型髋臼杯会改变髋臼周围骨的应力传递，导致松质骨出现应力遮挡，并增加皮质骨的负荷传递。从理论上讲，髋关节表面置换中更厚、更硬且更大的髋臼杯可能会增加髋臼周围骨的应力遮挡。我们试图通过测量髋关节表面置换（HR）期间植入厚整体钴铬（Co-Cr）髋臼部件一侧与对侧未手术侧髋臼上缘骨矿物质密度（BMD）的差异（术后至少2年）来评估这一问题。我们回顾性招募了44例因单侧髋关节骨关节炎接受金属对金属混合髋关节表面置换的患者。使用双能X线吸收测定法（DEXA）扫描测量双侧髋臼上缘骨的BMD。与未手术侧（1.70 g/cm²±0.49）相比，手术侧2区测量的BMD无差异（1.69 g/cm²±0.48）（p = 0.904）。与我们的预期相反，HR期间植入整体Co-Cr髋臼部件并未导致髋臼上缘松质骨出现明显的应力遮挡。
