Abstract
PURPOSE: To analyze the morphological characteristics of the lumbar 4 (L4)- Sacral 1 (S1) endplates in the Chinese young adults lumbar spine based on three-dimensional (3D) computed tomography (CT) scans, providing a reference for the design and application of intervertebral fusion devices. METHODS: We collected data from 33 patients with healthy lumbar spines and performed lumbar CT scans and 3D model reconstructions of the vertebral endplates. Sagittal and coronal dimensions of the concave areas of the endplates were measured from the L4 superior endplate to the S1 superior endplate, as was the depth of the most concave point in the concave areas of the endplates. The endplate morphology was classified and compared between sexes. RESULTS: In the sagittal plane, uniformly concave endplate, 20.6%; asymmetric concave, 32.7%; flat-bottomed concave, 12.1%; and flat endplate, 34.5%; in the coronal plane, uniformly concave endplate, 32.1%; asymmetric concave, 0.6%; flat-bottomed concave, 52.7%; and flat endplate, 14.5%. There were no statistically significant differences in the sagittal and coronal morphology of the lower lumbar endplates between sexes (p > 0.05). The depth of the most concave point in the lower endplate depression area of the L4 and L5 vertebral bodies was greater than that of the upper endplates, while the depth of the most concave point in the lower endplate depression area of the L4, L5, and S1 intervertebral spaces was smaller than that of the upper endplates of the superior vertebral bodies, with statistically significant differences (p < 0.05). There were no statistically significant differences in the maximum depth of depression in the sagittal and coronal planes of the endplates between different sexes at each segment (p > 0.05). CONCLUSIONS: The sagittal plane morphology of the lower lumbar endplate is mostly concave, whereas the sagittal plane morphology of the S1 endplate is mostly flat. Asymmetric endplates are less common in the coronal plane, and the endplates in the coronal plane are mostly symmetrically distributed. Sex has no significant effect on the morphology of the endplates.