Reliability and Validity of a Cervical Muscle Strength Test using a Load-cell-type Strength Measurement Sensor

Abstract

Background : Cervical disorder is caused by abnormal cervical movement patterns and cervical muscle imbalance, which are interrelated and result in neck pain and forward head position. In individuals with postural problems, measuring cervical muscle strength allows quantitative assessment of musculoskeletal damage and the effects of neck pain. Various devices have been used to measure cervical muscle strength. However, no studies have assessed cervical muscle strength using a load cell capable of measuring muscle strength in various postures and acquiring biofeedback in real time. Objectives : To evaluate the reliability and validity of a device designed to measure cervical muscle strength in the craniocervical and cervicothoracic regions using a load cell device fixed to a support plate. Methods : The participants were 15 individuals with neck pain. Superficial cervical muscle strength in cervicothoracic flexion (CTF) and cervicothoracic extension (CTE), as well as deep cervical muscle strength in craniocervical flexion (CCF) and craniocervical extension (CCE), were measured using an Hand-held dynamometer (HHD) and fixed-base isometric (load cell) dynamometry. The reliability and validity of the outcome measures using the two devices (HHD and load cell) in four positions were analyzed using intra-class coefficient (ICC) models 3 and 2. Results : Load cell measurements showed excellent intra-rater and inter-rater reliability. HHD measurements exhibited excellent intra-rater and inter-rater reliability. The load cell and HHD measurements showed moderate to excellent validity. Conclusions : The findings revealed excellent validity and reliability of load cell and HHD measurements of muscle strength. Thus, the load cell device can be used as an effective tool for assessing cervical strength. Also, the load cell can express muscle strength in Kilogramme rather than Newton. Therefore, the load cell can be used to measure muscle strength more easily than HHD.