Telemetry of forces from proximal femoral replacements and relevance to fixation
Telemetry of forces from proximal femoral replacements and relevance to fixation
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DOI：
10.1016/s0021-9290(96)00141-8
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发表时间：
1997-03-01
影响因子：
2.4
通讯作者：
Cannon, SR
中科院分区：
文献类型：
--
作者：
Taylor, SJG;Perry, JS;Cannon, SR
对两个近端股骨假体进行了器械固定，以确定假体内两个部位的轴向力：主轴内和髓内柄尖端附近。目标是测量力分布随时间的变化，如两个力的比率所示。在腿部周围佩戴的线圈和植入的小线圈之间使用感应耦合，既为密封在假体焊接腔中的电子电路供电，又为来自假体的遥测数据供电。两名受试者的数据均记录在手术后的前两年。对于第1例受试者，水平行走期间的平均轴力偏移（峰值力减去静息力）从1周后的0.53 x BW增加至23个月后的2.77 x BW。相应的平均头端力偏移分别为0.13 x BW和1.74 x BW。在同一时期内，平均头端力偏移与轴力偏移的比值从25%稳步增加至63%。在跑步机行走、爬楼梯和下楼梯过程中，发现尖端/轴比随时间推移出现类似增加。仅获得第二例受试者的轴力数据，与第一例受试者的数据一致。遥测记录的轴向载荷从IM股骨柄近端向远端逐渐转移，以及影像学观察结果表明，骨重建已经发生，股骨柄近端部分周围的界面稳定性较差。这个过程显然在植入后不久就开始了。(C)1997 Elsevier Science Ltd.
Two proximal femoral replacements were instrumented to enable axial forces to be determined at two sites within the prosthesis: in the main shaft and near the tip of the intramedullary stem. The goal was to measure the changes in force distribution over time, as indicated by the ratio of the two forces. Inductive coupling between a coil worn around the leg and a small implanted coil was used, both to supply power to electronic circuits sealed into a welded cavity in the prosthesis and to telemeter data from the prosthesis. Data from both subjects were recorded over the first two years following surgery. For the first subject, there was an increase in mean shaft force excursions (peak force minus resting force) during level walking from 0.53 x BW after 1 week to 2.77 x BW after 23 months. The corresponding mean tip force excursions were 0.13 x BW and 1.74 x BW, respectively. The ratio of mean tip force excursions to shaft force excursions steadily increased over the same period from 25 to 63%. Similar increases over time in the tip/shaft ratio were found during treadmill walking, stair climbing and stair descending. Data from the second subject were obtained for the shaft forces only, and were consistent with those from the first subject. The progressive transfer of axial load from the proximal to the distal part of the IM stem recorded telemetrically, together with radiographic observations, suggested that bone remodelling had taken place together with a less stable interface around the proximal part of the stem. This process evidently began soon after implantation. (C) 1997 Elsevier Science Ltd.