The Prevalence of Cervical Foraminal Stenosis on Computed Tomography of a Selected Community-Based Korean Population

BACKGROUND: Cervical foraminal stenosis (CFS) is one of the degenerative changes of the cervical spine; however, correlations between the severity of stenosis and that of symptoms are not consistent in the literature. Studies to date on the prevalence of stenosis are based on images obtained from the departments treating cervical lesions, and thus patient selection bias may have occurred. The purpose of this study was to investigate the prevalence of CFS according to the site, extent, and morphology of stenosis using cervical computed tomography (CT) images obtained from patients who were visiting not because of symptoms related to the cervical spine, cervical pain, or upper limb pain. METHODS: Among patients who underwent CT from January 2016 to March 2016 for reasons other than cervical spine symptoms, a total of 438 subjects were enrolled, and 2,628 cervical disc images (C4–5, C5–6, and C6–7; left and right sides) were examined. Three orthopedic surgeons performed two measurements each at 4-week intervals. Values were used for analysis if matched by more than two surgeons; if no match was found, the median values were used for analysis. The left and right sides on the same axial image were independently classified. RESULTS: Left C5–6 stenosis was most common (24.66%) among patients. At the left C6–7, there were 20 focal types and 33 diffuse types. At bilateral C4–5 and right C6–7, the focal type was more common, whereas at bilateral C5–6 and left C6–7, the diffuse type was more common. Age and the severity of stenosis showed statistically significant correlation at all cervical levels. CONCLUSIONS: The prevalence of CFS was highest at the C5–6 level (19.06%). Compared to other levels, focal stenosis was more frequent at C4–5 and diffuse stenosis was more common at C5–6. At C6–7, the incidence of focal stenosis was higher on the right side and that of diffuse stenosis was higher on the left side.