CONCURRENT VALIDITY AND TEST-RETEST RELIABILITY OF A WEARABLE INERTIAL SENSOR FOR MEASURING ACTIVE RANGE OF MOTION IN ASYMPTOMATIC HEALTHY VOLUNTEERS

M. Barbero¹, N. Castellini², S. Ballerini¹, A. Folli¹, G. Masoni¹, G. Mazzi¹, A. Tettamanti³, C. Cescon¹

¹University of Applied Sciences and Arts of Southern Switzerland, Department of Business Economics, Health and Social Care, Rehabilitation Research Laboratory 2rLab, Manno, Switzerland, ²Vita-Salute San Raffaele University, Master of Science in Rehabilitation Sciences, Milan, Italy, ³Universita Vita-Salute San Raffaele, Physiotherapy Degree Course, Milano, Italy

Background: Musculoskeletal disorders are the leading source of pain and disability globally. The range of motion (ROM) of the spine or peripheral joints is typically impaired by these disorders resulting in functional limitations and even reductions in quality of life. Measuring the ROM is a fundamental component in any physiotherapy physical examination, help to objectify the functional limitations and monitor patient progress after the interventions.

Purpose: The aim of this study is to examine the concurrent validity and test-retest reliability of an inertial sensor for measuring active joint range of motion.

Methods: A repeated measure study was conducted to assess test-retest reliability and concurrent validity. The study was conducted according to the Guidelines for Reporting Reliability and Agreement Studies (GRRAS). Ethical approval was granted by the local ethics Committee. All volunteers signed an informed consent prior to inclusion in the study. The study was conducted on 39 healthy volunteers enrolled at the Department of Business Economics, Health, and Social Care (DEASS) at the University of Applied Sciences and Arts of Southern Switzerland (SUPSI). The sample size was determined a priori during a previous pilot study. The joint ROM was determined with two systems: an IMU (RoMot, OT-Bioelettronica) and an optoelectronic motion capture system (Optitrack). Participants were asked to perform six active movements repeated three times each. The movements required were: shoulder flexion, shoulder abduction, cervical rotation, shoulder external rotation, knee flexion and ankle dorsiflexion. All six movements were used for test-retest reliability. While only the first three were considered for concurrent validity. Intraclass correlation coefficient (ICC) scores were calculated for concurrent validity and test-retest reliability using a two-way mixed model. The 95% CI of the ICC scores was interpreted by the Fleiss’ classification: above 0.90 was interpreted as excellent reliability, 0.75 – 0.90 good reliability, 0.50 – 0.75 moderate reliability, and less than 0.50 poor reliability Data analysis was performed with SPSS version 28.

Results: The ICC scores of concurrent validity, with a confidence interval (CI) of 95%, were between 0.93 and 0.99, with the highest values for cervical rotation. For the test-retest reliability, the ICC scores were between 0.89 and 0.98 with lower values for ankle dorsiflexion.

Conclusions: The investigated inertial sensor showed excellent concurrent validity compared to the optical motion system and very good test-retest reliability.

Implications: The investigated inertial sensor was revealed to be a valid and reliable instrument for the assessment of ROM on all the planes of movement and for the analysed joints, in particular the cervical rotation, the shoulder external rotation and the knee flexion.

Funding acknowledgements: n/a

Keywords:
Range of motion
Reliability
Inertial sensor

Topics:
Innovative technology: information management, big data and artificial intelligence
Innovative technology: robotics
Musculoskeletal

Did this work require ethics approval? Yes

Institution: Dipartimento della sanità e della socialità

Committee: Comitato etico cantonale

Ethics number: 2021-01014 CE 3874