CNRS, Laboratoire de Modélisation et de Simulation Multi-Echelle, UMR CNRS 8208, 61 Avenue du Général de Gaulle, Créteil 94010, France; INSERM U955, IMRB Université Paris-Est, 51 avenue du Maréchal de Lattre de Tassigny, 94000 Créteil, France.
CNRS, Laboratoire de Modélisation et de Simulation Multi-Echelle, UMR CNRS 8208, 61 Avenue du Général de Gaulle, Créteil 94010, France.
Clin Biomech (Bristol). 2020 Jun;76:105006. doi: 10.1016/j.clinbiomech.2020.105006. Epub 2020 Apr 26.
The success of cementless hip arthroplasty depends on the primary stability of the femoral stem. It remains difficult to assess the optimal number of impacts to guarantee the femoral stem stability while avoiding bone fracture. The aim of this study is to validate a method using a hammer instrumented with a force sensor to monitor the insertion of femoral stem in bovine femoral samples.
Different cementless femoral stem were impacted into five bovine femur samples, leading to 99 configurations. Three methods were used to quantify the insertion endpoint: the impact hammer, video motion tracking and the surgeon proprioception. For each configuration, the number of impacts performed by the surgeon until he felt a correct insertion was noted N. The insertion depth E was measured through video motion tracking, and the impact number N corresponding to the end of the insertion was estimated. Two indicators, noted I and D, were determined from the analysis of the time variation of the force, and the impact number N corresponding to a threshold reached in D variation was estimated.
The pullout force of the femoral stem was significantly correlated with I (R = 0.81). The values of N, N and N were similar for all configurations.
The results validate the use of the impact hammer to assess the primary stability of the femoral stem and the moment when the surgeon should stop the impaction procedure for an optimal insertion, which could lead to the development of a decision support system.
无水泥髋关节置换术的成功取决于股骨柄的初始稳定性。在保证股骨柄稳定性的同时避免骨折，评估最佳撞击次数仍然具有挑战性。本研究旨在验证一种使用带力传感器的锤子来监测牛股骨样本中股骨柄插入的方法。
将不同的无水泥股骨柄分别撞击到 5 个牛股骨样本中，共产生 99 种配置。使用三种方法来量化插入终点：冲击锤、视频运动跟踪和外科医生本体感觉。对于每种配置，记录外科医生感觉到正确插入所需的撞击次数 N。通过视频运动跟踪测量插入深度 E，并估计插入结束时的撞击次数 N。从力的时间变化分析中确定了两个指标，分别记为 I 和 D，并估计了 D 变化中达到阈值时的撞击次数 N。
股骨柄的拔出力与 I 显著相关（R=0.81）。所有配置的 N、N 和 N 值均相似。
研究结果验证了使用冲击锤评估股骨柄初始稳定性以及外科医生停止撞击程序以实现最佳插入的时刻的方法，这可能会导致决策支持系统的开发。
