Morphologic analysis of Chinese lumbar endplate by three-dimensional computed tomography reconstructions for helping design lumbar disc prosthesis

Lumbar disc prostheses have been used increasingly in recent years. The successful design of lumbar disc prostheses depends on accurate morphometric parameters. However, the morphologic dimensions of lumbar endplate area have not been investigated in Chinese population. A total of 1800 lumbar endplates were retrospectively accessed in 150 Chinese adults. Eighteen parameters of each lumbar segment were measured by three-dimensional computed tomography reconstructions from T12/L1 to L5/S1. These obtained parameters were compared between genders, bilateral sides, vertebral segments, and different populations. Endplate length and width increased in general, and there was a significant decrease for length/width ratio from T12 to S1 (P = .03). The average concavity depth of the lower lumbar endplate (2.09 ± 0.93 mm) was usually larger than that of the upper lumbar endplate (1.61 ± 0.74 mm) (P = .02). The percentage of the most concave point of the upper and lower lumbar endplate was 50.01 ± 10.76% and 56.41 ± 9.93%, respectively. Anterior, medium, or posterior intervertebral endplate height was severally 10.01 ± 1.98 mm, 10.46 ± 2.03 mm, and 6.41 ± 1.74 mm, and increased among vertebral segments (P = .01).The intervertebral endplate angle significantly increased from T12-L1 to L5-S1 (P = .01). Parameters displayed significant difference between genders. The morphometric parameters of different populations also showed differences. In conclusion, there is a morphologic discrepancy in dimensions of lumbar endplate regarding genders, vertebral segments, and different populations. It is essential to design the lumbar disc prosthesis suited for Chinese patients specially, for which the morphometric parameters in our study can be utilized.