Stagni R, Leardini A, Cappozzo A, Grazia Benedetti M, Cappello A
Dipartimento di Elettronica, Informatica e Sistemistica, Università degli Studi di Bologna, Viale Risorgimento, 2-40136, Bologna, Italy.
J Biomech. 2000 Nov;33(11):1479-87. doi: 10.1016/s0021-9290(00)00093-2.
Methods to determine the hip joint centre (HJC) location are necessary in gait analysis. It has been demonstrated that the methods proposed in the literature involve large mislocation errors. The choice should be made according to the extent by which HJC location errors distort the estimates of angles and resultant moments at the hip and knee joints. This study aimed at quantifying how mislocation errors propagate to these gait analysis results. Angles and moments at the hip and knee joint were calculated for five able-bodied subjects during level walking. The nominal position of the HJC was determined as the position of the pivot point of a 3D movement of the thigh relative to the pelvis. Angles and moments were then re-calculated after having added to HJC co-ordinates errors in the range of +/-30 mm. Angles and moments at both hip and knee joints were affected by HJC mislocation. The hip moments showed the largest propagation error: a 30 mm HJC anterior mislocation resulted in a propagated error into flexion/extension component of about -22%. The hip abduction/adduction moment was found the second largest affected quantity: a 30 mm lateral HJC mislocation produced a propagated error of about -15%. Finally, a 30 mm posterior HJC mislocation produced a delay of the flexion-to-extension timing in the order of 25% of the stride duration. HJC estimation methods with minimum antero-posterior error should therefore be preferred.
在步态分析中，确定髋关节中心（HJC）位置的方法是必要的。已有文献表明，文献中提出的方法存在较大的定位误差。应根据HJC位置误差对髋关节和膝关节角度及合力矩估计值的扭曲程度来进行选择。本研究旨在量化定位误差如何传播到这些步态分析结果中。在平地行走过程中，对五名身体健全的受试者的髋关节和膝关节角度及力矩进行了计算。HJC的标称位置被确定为大腿相对于骨盆三维运动的枢轴点位置。然后在HJC坐标中添加±30 mm范围内的误差后，重新计算角度和力矩。髋关节和膝关节的角度及力矩均受HJC定位误差的影响。髋关节力矩的传播误差最大：HJC向前错位30 mm会导致屈伸分量的传播误差约为-22%。髋关节外展/内收力矩是受影响第二大的量：HJC向外侧错位30 mm会产生约-15%的传播误差。最后，HJC向后错位30 mm会使屈伸时间延迟约为步幅持续时间的25%。因此，应优先选择前后误差最小的HJC估计方法。
