Anatomic study of the lumbar lamina for safe and effective placement of lumbar translaminar facet screws.

Objective: To evaluate the anatomic characteristics of the lumbar lamina and suggest a safe and effective strategy for setting lumbar translaminar facet screws.

Methods: The width and length of the lumbar lamina, screw path, lateral angle of the lamina, and maximum and minimum caudal angles of the lamina from L3 to L5 were measured with Mimics software using 32 patients’ computed tomographic data.

Results: The optimal screw entry point was located at the median of the spinous process base or slightly lower.