Objective Neck muscles provide more than 80% of the mechanical stability of the cervical spine. Deep neck flexor muscles including Longus Colli (LC) and longus capitis (LCA) play an important role in maintaining the cervical spine stability. Patients with chronic neck pain suffer from weakness and atrophy of neck flexor muscles. Ultrasonography measurement of muscle dimensions provides the ability to objectively assess muscle atrophy or hypertrophy. Therefore, the aim of this study was to evaluate the reliability of measurement of the cross-sectional area of LC and LCA muscles in five stages of craniocervical flexion (CCF) test utilizing ultrasonography.
Methods & Materials A total of 10 individuals including 5 patients suffering from chronic nonspecific neck pain and 5 healthy controls voluntarily participated in this study. The cross-sectional areas of LC and LCA muscles were measured at the level of thyroid cartilage during five stages while the subjects performed CCF test using a real-time ultrasound device. Two images were taken on the same day with an hour interval to assess the within-day reliability, and another image taken a week later to determine between-day reliability. SPSS was used to analyze data.
Results The ICC for within-day and between-day reliability in healthy individuals and patients were 0.91, 0.88 and 0.90, 0.86, respectively. The average standard error of measurement with the minimum of 0.03 and the maximum of 0.05 was obtained.
Conclusion Ultrasonography is a reliable method to measure the cross-sectional area of LC and LCA muscles both in healthy individuals and patients with chronic neck pain during five stages of the CCF test.