Previous studies have shown atrophy of paravertebral lumbar muscles in patients with lumbar radicular pain, and proposed rehabilitative approaches based on these findings. However, changes of cervical paravertebral muscles in patients with cervical radicular pain are still unknown. The aim of this study was to compare the cross-sectional area (CSA) of longus colli muscle (LCM) in patients with cervical radicular pain and healthy controls via ultrasound measurement.

Twenty patients with more than 4 weeks of cervical radicular pain and 20 healthy matched (for body mass index, age, and gender) control subjects. The CSA of LCM at the level of C5–C6 was measured by ultrasound with the subject in a supine position. Also, Neck Disability Index (NDI), and Visual Analogue Scale (VAS) were reported by patients. Independent sample t-test was used for investigation of differences in cross-sectional area and other variables between both groups.

Twenty patients with cervical radicular pain with mean (SD) age of 42.4(7) years and 20 healthy matched controls with mean (SD) age of 40.7 (7) years participated in the study. Patients with cervical radicular pain showed smaller CSA of LCM bilaterally compared with controls [mean (SD) difference: 0.37(0.15)] (P-value<0.001). Within patients group, there were no significant differences between CSA of LCM in the involved and non-involved sides.

This is the first study which showed that patients with cervical radicular pain had smaller bilateral CSA of LCM in comparison with healthy controls via ultrasound assessment. It is also not clear whether atrophy of longus colli muscle in patients with cervical radicular pain is a consequence or a cause of it. Reduction in the stability of neck due to atrophy of LCM could make the cervical spine region susceptible to more injuries which might be prevented by functional and strengthening exercises.