OBJECTIVETo discuss the correlation between the degree of cervical spinal cord compression and gender, age, height of intervertebral space and the abnormality curvature of cervical vertebrae. The multivariable linear regression was used to build the prediction model of cervical spinal cord compression.

METHODSOne hundred and twenty patients with cervical spondylosis were divided into 4 groups according to the degree of spinal cord compression. To measure the sagittal diameter of spinal cord (a) and medulla-pons junction (M) in MRI individually, and then calculate the ratio of a/M; according to the ratio to evaluate the degree of cervical spinal cord compression. In X-ray films to measure the height and angle of intervertebral space, curvature of cervical vertebrae (according to Borden's method and double line method of C2-7 Cobb angle to abtain data of curvature of cervical vertebrae). To performe linear regression and multiple linear regression to analyze the correlation above the data and build the prediction model of cervical spinal cord compression.

RESULTS(1) With the exacerbation of cervical spinal cord compression, all measured data gradually decreased; there was significant difference in the anterior height and angle of intervertebral space, the ratio of a/M between any two groups (P < 0.05). (2) The ratio of a/M showed positive corrrelation with the anterior height of intervertebral space (R = 0.296, P < 0.001) and the curvature of cervical vertebrae (are to chord distance, R = 0.241, P < 0.001), but showed negative corrrelation with the proportion of cervical spinal cord compression (R = -0.821, P < 0.001); Borden's method are to chord distance) showed positive correlation with the double line method of C2-7 Cobb angle (R = 0.840, P < 0.001). The predictive equation of the ratio of a/M by multiple linear regression was obtained, and the F = 8.959, R = 0.434, P < 0.001, in which the age, the anterior height of intervertebral space and the curvature of cervical vertebrae were risk factors of cervical spinal cord compression.

CONCLUSIONThe ratio of a/M can be a standard to evaluate degree of cervical spinal cord compression; the changes of the height of intervertebral disc, curvature of cervical vertebrae in X-ray films maybe have values to predict the degree of cervical spinal cord compression.