Stagni Rita, Fantozzi Silvia, Cappello Angelo
Dipartimento di Elettronica, Informatica e Sistemistica, Università di Bologna, Viale Risorgimento 2, 40136 Bologna, Italy.
Gait Posture. 2006 Oct;24(2):137-41. doi: 10.1016/j.gaitpost.2006.08.001. Epub 2006 Aug 24.
Soft tissue artefact and anatomical landmark misplacement have been recognized as the most critical sources of error in gait analysis. The double calibration method was recently proposed to compensate for soft tissue artefact in knee kinematics. This compensation method resulted very effective in the absence of anatomical landmark misplacement. The purpose of the present work was to assess the effectiveness of double calibration in reducing the effects of skin motion artefact on knee rotations and translations when anatomical landmark misplacement is present on the thigh and shank. The double calibration method was used to calculate knee kinematics of two subjects while they performed several motor tasks. The results were compared with those from conventional single calibration. The soft tissue artefact propagated to knee kinematics was quantified by simulating different misplacement errors using both single and double calibration. The double calibration method performed much better than the single calibration one in quantifying knee rotations and particularly translations, with misplacement error up to 15mm superimposed on the anatomical coordinates of the epicondyles. If misplacement errors were limited to just 5mm, the double calibration would be effective in providing kinematics accurate enough for orthopaedic biomechanic applications.
软组织伪影和解剖标志点错位已被公认为步态分析中最关键的误差来源。最近提出了双校准方法来补偿膝关节运动学中的软组织伪影。在不存在解剖标志点错位的情况下，这种补偿方法非常有效。本研究的目的是评估当大腿和小腿存在解剖标志点错位时，双校准在减少皮肤运动伪影对膝关节旋转和平移影响方面的有效性。使用双校准方法计算两名受试者在执行多项运动任务时的膝关节运动学。将结果与传统单校准的结果进行比较。通过使用单校准和双校准模拟不同的错位误差，对传播到膝关节运动学的软组织伪影进行量化。在量化膝关节旋转尤其是平移方面，双校准方法比单校准方法表现得好得多，在髁上解剖坐标上叠加高达15毫米的错位误差时也是如此。如果错位误差仅限于5毫米，双校准将有效地提供足够准确的运动学数据用于骨科生物力学应用。
