Leali Alex, Fetto Joseph F
Department of Orthopaedic Surgery, New York University Hospital for Joint Diseases, New York, NY, USA.
Int Orthop. 2004 Jun;28(3):151-4. doi: 10.1007/s00264-004-0554-1.
Uncemented, porous-coated femoral stems rely on bone in-growth to achieve stable, long-lasting fixation. The loss of proximal femoral bone mass around hip stems has been traditionally termed "stress shielding" and has been linked to the transfer of loads to the diaphysis and the relative unloading of the proximal femur. A total of 10 total hip arthroplasties with a proximally coated lateral flare device designed to engage both cortices at the metaphyseal level were evaluated with dual-energy X-ray (DEXA) absorptiometry and qualitative radiographic changes 3 weeks after surgery and at 12, 24 and 52 weeks thereafter. All hips were radiologically stable. The DEXA measurements revealed an overall increase in the bone mineral density (BMD) at 52 weeks of 3%. Greater gains were observed at or below the lateral flare of the stem in the metaphyseal femur.
非骨水泥型、多孔涂层股骨柄依靠骨长入来实现稳定、持久的固定。传统上，髋关节柄周围股骨近端骨量的减少被称为“应力遮挡”，并与负荷向骨干的转移以及股骨近端的相对卸载有关。共有10例全髋关节置换术，其近端涂层外侧扩口装置设计用于在干骺端水平与双侧皮质接合，在术后3周以及此后的12周、24周和52周通过双能X线吸收法（DEXA）和定性影像学变化进行评估。所有髋关节在放射学上均稳定。DEXA测量显示，在52周时骨矿物质密度（BMD）总体增加了3%。在股骨干骺端柄外侧扩口处或其下方观察到更大的增加。
