Establishment of the Lunar Phase Morphological Classification for Cervical Spinal Canal
- Author:
Zhongyi CUI
1
;
Hongwei WANG
;
Yuan SUN
;
Weibo HUANG
;
Fei ZOU
;
Xiaosheng MA
;
Feizhou LYU
;
Jianyuan JIANG
;
Hongli WANG
Author Information
- Publication Type:Clinical Study
- From:Asian Spine Journal 2024;18(1):110-117
- CountryRepublic of Korea
- Language:English
-
Abstract:
Methods:The median sagittal diameter and transverse diameter of the spinal canal from C2 to C7 were measured on CT images. The ratio of the median sagittal diameter to the transverse diameter was calculated. Accordingly, the spinal canal shape of each segment was classified into four, and the specific criteria of lunar phase classification were determined through linear discriminant analysis based on the ratio of the median sagittal diameter to the transverse diameter. The inter-rater reliability of the classification was explored using Kappa coefficients. Finally, the morphology of the different segments of the cervical spinal canal in healthy volunteers was revised and compared.
Results:According to the ratio of the median sagittal diameter and the transverse diameter of the cervical spinal canal, the lunar phase classification of the cervical bony spinal canal was determined as follows: full-moon >0.65, 0.55< convex-moon ≤0.65, 0.46≤ quarter-moon ≤0.55, and residual-moon <0.46. The Kappa values of C2–C7 were 0.851, 0.958, 0.823, 0.927, 0.793, and 0.946, and the Kappa value of all C2–C7 segments was 0.854 that mainly presented two forms of full-moon (76.5%) and convex-moon (23.0%). A quarter-moon spinal canal was mainly distributed in C3, C4, C5, and C6; a residual-moon spinal canal was mainly distributed in C4 and C5; and the morphological distribution of C4 and C5 were similar (p>0.05). The frequency of the spinal canal of the residual-moon type was the highest, and the full-moon (6.5%) and residual-moon (7.5%) types of C7 were rare.
Conclusions:The morphological classification of the cervical spinal canal was established to present anatomical variations. The classification showed good inter-rater reliability.
