The purposes of this study were to validate lateral radiographic measurements of PVST width using upright weight-bearing MRI in healthy subjects and quantify effects of spinal level and gender.
Clinical study in asymptomatic volunteers.
Eleven male and eight female volunteers consented and were enrolled in the study. All volunteers were asymptomatic and had no history of cervical spine injury or degenerative disease. Prevertebral soft-tissue width was measured at each cervical level from C2 to C7 using upright weight-bearing MRI. Statistically significant differences in PVST width based on spinal level and gender were determined using two-factor analysis of variance.
Width magnitudes were significantly dependent on gender (p<.0001) and spinal level (p<.0001). All C3 and C6 measurements were below the traditionally accepted values of 7 and 20 mm, respectively, that would be considered “abnormal.” Prevertebral soft-tissue width was greater in men at upper and lower extents of the cervical spine. Prevertebral soft-tissue widths reported in the present study were similar in magnitude and level-by-level trends to measurements of asymptomatic volunteers obtained using lateral radiography.
The present study validated the use of lateral radiography to measure PVST width, presented level-by-level and gender-specific normative data, and provided a weighted statistical analysis of differences between normal volunteers and injured patients.