Study on inferior lumbar lateral recess of normal adults by autopsy anatomy and helical CT

Objective: To investigate the morphology and measurement of lumbar lateral recess in normal adults and explore the diagnosis of lateral recess stenosis. Methods: Autopsy anatomy and helical CT (muti-plane volume reconstruction, MPVR and surface shading display, SSD) were used to observe the lateral recess. The upper 1/4 transverse plane was elected as study plane. The sagital diameters of lateral recess and medial sagittal diameters of vertebral canal of 120 lumbar vertebrae were measured and the ratios of them were calculated. U-test was used to test the results. Results: Inferior lumbar lateral recess could be classified into 3 types: triangular, clover and ox horn. The bilateral sagittal diameters of normal adults were asymmetry. The right side was slightly lager than the left side (P0.05). The ratios of medial sagittal diameter of vertebral canal and sagittal diameter of bilateral lateral recess are relatively invariable: medial/right=3.93, medial/left=4.03. Conclusion: Electing upper 1/4 transverse plane of vertebrae as entrance plane of lateral recess, the method using sagittal diameter ratio to diagnose lateral recess stenosis is more scientific. [