A strathclyde cluster model for gait kinematic measurement using functional methods: a study of inter-assessor reliability analysis with comparison to anatomical models

A major source of error in reliability of gait analysis arises from the palpation of anatomical landmarks (ALs). The purpose of this study was to investigate whether less reliance on manually identifying ALs could improve inter-assessor reliability of joint kinematics compared to two anatomical models. It was hypothesised that the Strathclyde functional cluster model (SFCM), in which the hip, knee and ankle joint centres and knee and ankle flexion axes were determined by functional methods, would obtain greater inter-assessor reliability. Ten able-bodied participants and seven assessors were recruited. Each participant completed three trials conducted by different assessors on non-consecutive days. Agreement and inter-assessor reliability between the models were compared and analysed, whilst factor effects of assessor experience and body mass index (BMI) were investigated. The SFCM obtained excellent agreement with anatomical models for all sagittal angles and hip ab/adduction angle, and it showed slightly higher inter-assessor reliability with smaller variations in the knee and ankle. The assessor experience was not a significant factor, but the BMI had a significant effect on the inter-assessor reliability. The results demonstrate that the SFCM may be more beneficial for less experienced assessors.

步态分析可靠性的主要误差来源之一，源于解剖标志点（Anatomical Landmarks, ALs）的触诊操作。本研究旨在探究，相较于两类解剖学模型，降低手动识别解剖标志点的依赖程度是否能够提升关节运动学的评估者间信度。本研究假设：通过功能学方法确定髋关节、膝关节与踝关节的关节中心，以及膝关节与踝关节屈伸轴的斯特拉斯克莱德功能集群模型（Strathclyde Functional Cluster Model, SFCM），可获得更高的评估者间信度。本研究招募了10名健康受试者与7名评估者，每名受试者在非连续的天数内，完成由不同评估者实施的3次测试。研究对两类模型间的一致性与评估者间信度进行了比较分析，同时探究了评估者经验与身体质量指数（Body Mass Index, BMI）对结果的影响效应。结果显示，斯特拉斯克莱德功能集群模型在所有矢状面角度以及髋外展/内收角度上，与解剖学模型均表现出极佳的一致性；且在膝关节与踝关节指标上，其评估者间信度略高，变异程度更小。评估者经验未对结果产生显著影响，但身体质量指数对评估者间信度存在显著效应。研究结果表明，斯特拉斯克莱德功能集群模型或许更适合经验相对不足的评估者使用。