Clinic for Orthopedics, Heidelberg University Hospital, Heidelberg, Germany.
Clinic for Orthopedics, Heidelberg University Hospital, Heidelberg, Germany.
Gait Posture. 2023 Jun;103:57-61. doi: 10.1016/j.gaitpost.2023.04.017. Epub 2023 Apr 25.
The determination of the knee joint axis (KJA) via specific calibration movements has become a promising alternative to the conventional approach to determine this axis based on regression equations or directly via marker placement on bony landmarks of the knee. Since the orientation of the KJA may differ between methods, it has direct influence on hip rotation and may therefore influence clinical decision making in context of transverse plane gait deviations.
Does a functional KJA calibration lead to clinically relevant differences in hip rotation estimates during gait compared to the conventional method?
95 subjects (age: 19.9 years; BMI: 21.1 kg/m), including 71 patients with potential rotation malalignment, were prospectively examined and underwent 3D gait analysis. For the conventional approach the KJA was determined by applying a knee alignment device, for the functional approach subjects were asked to perform two different calibration movements. Each procedure was performed twice. Mean hip rotation in stance (mHipRotSt) was determined following the conventional and the functional KJA calibration.
Deming regression analysis for the comparison of conventional and functionally measured hip rotation revealed a systematic and substantial difference between methods (slope: 0.63; intercept: 0.31°). Measurement repetition with the knee alignment device revealed typical errors around 5°, whereas the functional methods lead to profoundly smaller errors around 1-2° with slightly inferior results for SQUAT compared to FLEX. However, when compared to conventional frontal plane video-taping, the conventional method seemed to reflect the more consistent results.
The systematic linear discrepancy in mHipRotSt obtained by a functional approach as compared to the conventional approach appears critical since patients with severe internal or external rotation gait may be misjudged in function when receiving corrective procedures such as femoral derotation osteotomy.
通过特定的校准动作来确定膝关节轴（KJA）已成为一种有前途的替代传统方法的方法，传统方法是基于回归方程或直接通过在膝关节的骨性标志上放置标记来确定该轴。由于 KJA 的方向可能因方法而异，因此它直接影响髋关节旋转，并且可能会影响在横断面上步态偏差的情况下的临床决策。
与传统方法相比，功能性 KJA 校准在步态期间是否会导致髋关节旋转估计的临床相关差异？
95 名受试者（年龄：19.9 岁；BMI：21.1kg/m²），包括 71 名潜在旋转错位的患者，前瞻性检查并进行了 3D 步态分析。对于传统方法，通过应用膝关节对准装置来确定 KJA，对于功能方法，要求受试者执行两种不同的校准动作。每个程序执行两次。在常规和功能 KJA 校准后，确定站立时的平均髋关节旋转（mHipRotSt）。
对常规和功能测量的髋关节旋转进行的 Deming 回归分析显示，两种方法之间存在系统且实质性的差异（斜率：0.63；截距：0.31°）。使用膝关节对准装置进行测量重复时，误差约为 5°，而功能方法导致的误差约为 1-2°，深蹲时的结果略差于 Flex。然而，与常规的额状面视频录制相比，常规方法似乎反映了更一致的结果。
与传统方法相比，功能方法获得的 mHipRotSt 中系统的线性差异似乎很关键，因为接受诸如股骨旋转移位截骨术等矫正程序的严重内旋或外旋步态的患者在功能上可能会被错误判断。
