Ultrasonographic cross-sectional area of spinal nerve roots in cervical radiculopathy: a pilot study.

Recently, sonographic assessment has been considered an alternative method for evaluating cervical root lesions. The aim of this pilot study was to measure cross-sectional areas (CSAs) of cervical spinal nerve roots using high-resolution ultrasonography in patients with cervical radiculopathy, to compare the CSA of nerve roots between the affected and unaffected sides. Patients with a clinical diagnosis of unilateral cervical radiculopathy, who were referred to the Department of Physical Medicine and Rehabilitation in the University General Hospital by general practitioners, were prospectively recruited. The selected nerve roots were sonographically imaged at the most proximal location possible, where they exited over the transverse processor, just distal to that point. The CSA was measured three times using the trace tool available on the ultrasonography device. The CSA of each contralateral nerve root served as a control. Twenty-four patients (9 women; mean age, 53.7 yrs) were enrolled in this study. The CSAs were measured by ultrasonography in 5 pairs of C5 roots, 12 pairs of C6 roots, and 7 pairs of C7 roots. The mean CSAs of the affected and unaffected sides were 9.74 ± 1.95 and 9.47 ± 1.95 mm, respectively (P = 0.019). Spearman rank-order correlation test showed a positive relationship between the CSA of the affected nerve root and the duration of symptoms (ρ22 = 0.467, P = 0.021).This is, to the authors' knowledge, the first comparative study to obtain the CSA of spinal nerve roots in cervical radiculopathy. Increased CSA of the affected nerve root relative to the unaffected side, as demonstrated by ultrasonography, may be useful as an additive clue for the diagnosis of cervical radiculopathy.