Pitto Rocco P, Bhargava Aknaksha, Pandit Salil, Walker Cameron, Munro Jacob T
Department of Orthopaedic Surgery, University of Auckland, Auckland, New Zealand.
Int Orthop. 2008 Oct;32(5):589-95. doi: 10.1007/s00264-007-0389-7. Epub 2007 Jun 20.
The aim of this prospective study was to measure bone density changes and to assess adaptive bone remodelling after uncemented total hip arthroplasty with a taper-design femoral component using quantitative computer-tomography-assisted osteodensitometry. This method is able to differentiate cortical and cancellous bone structures. Twenty-seven consecutive patients (29 hips) with degenerative joint disease were enrolled in the study. Serial clinical, radiological and CT-osteodensitometry assessments were performed after the index operation. At the 2-year follow-up, the clinical outcome was rated satisfactory in all hips. The radiological assessment showed signs of osteointegration and stable fixation of all cups and stems. We observed a -17% decrease of cortical bone density and -22% decrease of cancellous bone density in the greater trochanter and femoral neck region. Cortical and cancellous bone density decrease at the level of the lesser trochanter was -9% and respectively -4%. We observed small changes of cortical bone density in the diaphyseal regions; in contrast, cancellous bone density increased (range 6% to 27%) in the diaphyseal regions. Overall, a trend of bone density recovery was observed throughout the follow-up period. Periprosthetic bone density changes at the 2-year follow-up are suggestive of stable osteointegration with proximal femoral diaphysis load transfer and moderate metaphyseal stress-shielding.
这项前瞻性研究的目的是,使用定量计算机断层扫描辅助骨密度测定法,测量采用锥形设计股骨组件的非骨水泥型全髋关节置换术后的骨密度变化,并评估适应性骨重塑。该方法能够区分皮质骨和松质骨结构。连续纳入27例(29髋)患有退行性关节疾病的患者进行研究。在初次手术后进行系列临床、放射学和CT骨密度测定评估。在2年随访时,所有髋关节的临床结果均评定为满意。放射学评估显示所有髋臼杯和股骨柄均有骨整合迹象且固定稳定。我们观察到,大转子和股骨颈区域的皮质骨密度下降了17%,松质骨密度下降了22%。小转子水平的皮质骨密度和松质骨密度下降分别为9%和4%。我们观察到骨干区域的皮质骨密度有微小变化;相反,骨干区域的松质骨密度增加(范围为6%至27%)。总体而言,在整个随访期间观察到骨密度恢复的趋势。2年随访时假体周围骨密度变化提示与股骨近端骨干负荷转移和中度干骺端应力遮挡形成稳定的骨整合。