Ab. No. 55 Using Inertial Measurement Units (IMU) for Measuring Neck Range of Motion (ROM) in Persons With Neck Pain: a Validity and Reliability Study

Abstract

Introduction: Neck pain is one of the top five leading causes of disability in people around the globe. Range of Motion (ROM) is a fundamental clinical measure used to examine movement of joints in the body. A Universal goniometer is used to manually measure the ROM, this may be prone to measurement errors. Inertial Measurement Units (IMU) sensors detect the linear acceleration and angular velocity. They could be utilized to evaluate joint ROM, as they are relatively inexpensive and can be calibrated to convenience. The study aims to validate the device using an Optical motion capture system (OMCS) (Phase 1) and To measure the test-retest reliability of the device in the clinical setup in people with neck pain (Phase 2) Methods: Phase 1: Validation of the IMU was done against OMCS in Bioengineering department for Neck flexion, extension, lateral flexion and rotation (both left and right) on two consecutive days for 34 individuals. Phase 2: Forty patients with neck pain were recruited from Outpatient Physiotherapy unit, CMC Vellore. Data was recorded by the IMU system and stored on a computer. Patients were reassessed again to test the reliability on another day. The same clinician administered the assessments for all patients. Result: Phase 1 - The correlation coefficient was found to be excellent between the IMU and OMCS for all movements of the neck. Neck angle error - 2.19 to 4.20. Phase 2 - Intra-rater reliability of the device was assessed and it was found to be moderate to good among people with neck pain. The ICC ranged from 0.62 to 0.83 for the different neck ROM. Conclusion: The use of IMU for measuring neck ROM is a valid and reliable tool. It can be a useful clinical tool for consistent measurement and accurate documentation in the future.