A new device for measuring isometric force of the craniocervical flexor and extensor muscles and its reliability

Abstract

Objective: Craniocervical (CC) muscles control posture of the CC area. Muscle imbalance at this area induces musculoskeletal disorders. The purpose of this study was to develop a device for measuring isometric force of CC flexor and extensor muscles and to evaluate its intra-rater reliability.Method: Isometric force of CC flexor and extensor muscles was measured in 20 women by one examiner on two days with a custom-made device. The intra-class correlation coefficient (ICC), standard error of measurements (SEM), smallest detectable difference (SDD), and Pearson correlation coefficient were computed.Results: The results of this study revealed that this device had excellent reliability (ICC: 0.98, SEM: 2.29 N, SDD: 6.36 N, Pearson correlation coefficient: 0.97 for CC flexor muscles and ICC: 0.97, SEM: 2.13 N, SDD: 5.91 N, Pearson correlation coefficient: 0.94 for CC extensor muscles).Discussion: This new device can improve knowledge about the CC muscle and efficacy of treatments in patients with poor posture.