Franco Luca, Sengupta Raj, Wade Logan, Cazzola Dario
Department for Health, University of Bath, Bath, UK.
Centre for Analysis of Motion, Entertainment Research and Application, Bath, UK.
PeerJ. 2021 Jan 26;9:e10623. doi: 10.7717/peerj.10623. eCollection 2021.
Clinical assessment of spinal impairment in Axial Spondyloarthritis is currently performed using the Bath Ankylosing Spondylitis Metrological Index (BASMI). Despite being appreciated for its simplicity, the BASMI index lacks sensitivity and specificity of spinal changes, demonstrating poor association with radiographical range of motion (ROM). Inertial measurement units (IMUs) have shown promising results as a cost-effective method to quantitatively examine movement of the human body, however errors due to sensor angular drift have limited their application to a clinical space. Therefore, this article presents a wearable sensor protocol that facilitates unrestrained orientation measurements in space while limiting sensor angular drift through a novel constraint-based approach. Eleven healthy male participants performed five BASMI-inspired functional movements where spinal ROM and continuous kinematics were calculated for five spine segments and four spinal joint levels (lumbar, lower thoracic, upper thoracic and cervical). A Bland-Altman analysis was used to assess the level of agreement on range of motion measurements, whilst intraclass correlation coefficient (ICC), standardised error measurement, and minimum detectable change (MDC) to assess relative and absolute reliability. Continuous kinematics error was investigated through root mean square error (RMSE), maximum absolute error (MAE) and Spearman correlation coefficient (ρ). The overall error in the measurement of continuous kinematic measures was low in both the sagittal (RMSE = 2.1°), and frontal plane (RMSE = 2.3°). ROM limits of agreement (LoA) and minimum detectable change were excellent for the sagittal plane (maximum value LoA 1.9° and MDC 2.4°) and fair for lateral flexion (overall value LoA 4.8° and MDC 5.7°). The reliability analysis showed excellent level of agreement (ICC > 0.9) for both segment and joint ROM across all movements. The results from this study demonstrated better or equivalent accuracy than previous studies and were considered acceptable for application in a clinical setting. The protocol has shown to be a valuable tool for the assessment of spinal ROM and kinematics, but a clinical validation study on Axial Spondyloarthritis patients is required for the development and testing of a novel mobility index.
目前，轴性脊柱关节炎患者脊柱损伤的临床评估采用的是巴氏强直性脊柱炎计量指数（BASMI）。尽管BASMI指数因其简单性而受到认可，但其缺乏对脊柱变化的敏感性和特异性，与影像学活动范围（ROM）的关联性较差。惯性测量单元（IMU）作为一种经济有效的人体运动定量检测方法已显示出有前景的结果，然而，由于传感器角度漂移导致的误差限制了其在临床领域的应用。因此，本文提出了一种可穿戴传感器方案，该方案通过一种新颖的基于约束的方法，在限制传感器角度漂移的同时，便于在空间中进行无约束的方向测量。11名健康男性参与者进行了五项受BASMI启发的功能性运动，针对五个脊柱节段和四个脊柱关节水平（腰椎、下胸椎、上胸椎和颈椎）计算脊柱ROM和连续运动学参数。采用Bland-Altman分析评估运动范围测量的一致性水平，同时使用组内相关系数（ICC）、标准化误差测量和最小可检测变化（MDC）来评估相对和绝对可靠性。通过均方根误差（RMSE）、最大绝对误差（MAE）和斯皮尔曼相关系数（ρ）研究连续运动学误差。连续运动学测量的总体误差在矢状面（RMSE = 2.1°）和额状面（RMSE = 2.3°）均较低。矢状面的一致性界限（LoA）和最小可检测变化非常好（最大LoA值1.9°，MDC 2.4°），而侧屈的一致性一般（总体LoA值4.8°，MDC 5.7°）。可靠性分析表明，所有运动中节段和关节ROM的一致性水平都非常高（ICC > 0.9）。本研究结果显示出比以往研究更好或相当的准确性，被认为可接受用于临床环境。该方案已被证明是评估脊柱ROM和运动学的有价值工具，但要开发和测试一种新的活动指数，还需要对轴性脊柱关节炎患者进行临床验证研究。
