Validation of a novel range of motion assessment tool for the cervical spine: the HALO

Background: Cervical spine range of motion (ROM) assessment has long been carried out via use of the universal goniometer (UG) as an objective tool in the evaluation of patient rehabilitation pre- and post-operatively. The advent of novel ROM assessment technology, such as HALO digital goniometer (DG), presents an avenue for research and potential application within clinical and surgical settings. The objective of this study was to examine the reliability and validity of the HALO DG in the assessment of the active ROM of the cervical spine. Methods: One hundred healthy subjects were recruited for the study and were split into two groups to be assessed by either physiotherapists or medical students. The methodology for cervical spine ROM assessment was carried out per the American Association of Orthopaedic Surgeons (AAOS) guidelines. The reliability analysis was completed using IBM SPSS Statistics 25, calculating the intraclass correlation coefficients (ICC) to determine both the intra- and inter-rater reliability of the device. Results: Inter-rater reliability within the physiotherapist cohort with the DG (ICCr =0.477, 0.718, 0.551) was higher compared to the UG (ICCr =0.380, 0.510, 0.255) for active cervical flexion, lateral flexion, and rotation, respectively. The UG (ICCr =0.819) showed better reliability versus the DG (ICCr =0.780) when assessing cervical extension. Similarly, in the medical student cohort, the DG outperformed the UG in all movement except cervical lateral flexion. When assessing for intra-rater reliability, the DG (ICCm =0.507, 0.773, 0.728, 0.691) performed better than the UG (ICCm =0.487, 0.529, 0.532, 0.585) in cervical flexion, extension, lateral flexion, and rotation, respectively. Conclusions: The present validation study identified the DG as a reliable substitute for the UG.