Measurement of Cervical Multifidus and Longus Colli Muscle Dimensions in Patients With Cervical Radiculopathy and Healthy Controls Using Ultrasonography: A Reliability Study

Background: Cervical radiculopathy is a musculoskeletal disorder with an increasing prevalence in office workers. In recent years, ultrasonography (US) has been reported to be a valid, inexpensive, and noninvasive technique for the objective evaluation of muscle morphology. However, measuring deep cervical paraspinal muscle dimensions using US in patients with cervical radiculopathy has not been described. Objective: To evaluate intrasession and intersession reliabilities of US to measure dimensions of deep cervical muscles at rest in patients with chronic cervical radiculopathy and healthy controls. Design: Reliability study. Setting: Outpatients who presented for treatment at an outpatient university physiotherapy clinic. Participants: Fifteen patients with cervical radiculopathy and 15 healthy controls. Interventions: US measurements. Outcome: Cervical multifidus and longus colli muscle dimensions at separate occasions. Methods: Two measurements separated by a 1-hour interval were taken on the same day and the third measurement was taken 5 days later. The intraclass correlation coefficient (ICC), SE of measurement, and minimal detectable change were used to evaluate relative and absolute reliabilities. Results: US was a highly reliable method for measuring the multifidus and longus colli muscle dimensions in patients and healthy subjects. The highest reliability scores were found for the anteroposterior dimension measurement of the multifidus muscle (ICC = 0.92) and the lateral dimension measurement of the longus colli muscle (ICC = 0.97) in healthy subjects. Conclusions: The results indicated that US is a highly reliable method of measuring deep cervical muscle dimensions in patients with cervical radiculopathy and healthy controls when measured by the same investigator.