X-ray measurement of anatomical, natural and pathological heights of cervical intervertebral disc and its clinical significance / 第二军医大学学报

ABSTRACT

Objective To propose the three heights of intervertebral disc during cervical disc degeneration by measuring the cervical intervertebral disc heights in patients with cervical spondylosis. Methods Totally 96 patients with cervical spondylosis undergoing surgery in our hospital from Jan. 2017 to May 2017 were enrolled in this study, and their intervertebral disc heights of C2-7 were measured by the lateral X-ray. The patients were divided into 3 groups according to the Pfirrmann score anatomical height group (Pfirrmann score-Ⅱ grade without height loss), natural height group (Pfirrmann score III grade), and pathological height group (Pfirrmann score -grade with moderate and severe intervertebral height loss). Two-way ANOVA and LSD analysis were performed to compare the intervertebral disc heights between the three groups. Results The average age of 96 patients was (53.4±19.6) years old, with 57 males and 39 females. Fifty-nine cases were diagnosed with cervical spondylotic myelopathy, 25 with nerve root type cervical spondylosis, and 12 with mixed cervical spondylosis. The average intervertebral disc heights in the anatomic height, natural height and pathological height groups were (7.7±1.2) mm, (7.1±0.9) mm and (5.9±1.0) mm, respectively, and there were significant differences between the three groups (all P<0.01). The cut-off values (sensitivity, specificity) of the anatomical heights and natural heights, natural heights and pathological heights of C3-4, C4-5, C5-6 and C6-7 were 7.45 mm (0.62, 0.65) and 6.95 mm (0.63, 1.00), 7.75 mm (0.49, 0.85) and 6.10 mm (0.89, 0.43), 7.75 mm (0.59, 0.77) and 6.95 mm (0.66, 0.91), and 7.85 mm (0.61, 0.89) and 5.95 mm (0.86, 0.73), respectively. Conclusion During the process of degeneration, cervical disc height can be classified as anatomical height, natural height (degenerative height) and pathological height. We should pay attention to the intervertebral disc height before operation and suggest to restore natural disc height.