Concurrent validity of three measurement systems for the evaluation of cervical spine mobility
In this study, we compared the cervical range of movement (ROM) and range of angular velocity (RAV) measured simultaneously using a 3-dimensional electrogoniometer, the CA6000-OSI (OSI), an optoelectronic motion capture system (MCS), the VICON® and a wearable system (WS) composed of inertial measurement units, the Physilog®. Measurement of primary and associated cervical movement during active lateral bending (LB), axial rotation (AR) and flexion-extension (FE) were compared from those systems in 10 healthy subjects according to two tasks of movement: with the best amplitude possible (BEST) and the fastest possible (FAST). For primary components of movement, ROM absolute differences between respectively WS and MCS, MCS and OSI and WS and OSI were 5%, 3% and 7% of mean ROM for the BEST task and 7%, 4% and 11% for the FAST task. RAV absolute differences were 6%, 11% and 13% respectively for BEST task and 11%, 20% and 20% for FAST task. ICC between 0.96 and 0.99 were obtained. CMC for angular and velocity patterns were between 0.95 and 0.99. The three systems must be considered as usual and confident tools to assess the normal and fast cervical motion. A better correlation between the different systems is observed during the BEST task.