Abstract

INSTITUTION WHERE THE STUDY WAS REALIZED: Institute of Orthopaedics and Traumatology and Morgue of São Paulo University Teaching Hospital (Hospital das Clinicas) – Medicine College of São Paulo University PRESENTER: CHOI, PIL SUN Submitted for presentation: (x) computer Study Design: The lumbar pedicle morphometry and its relationship to the adjacent neural structures from L2-S1 were investigated by anatomic dissection in 14 human male adult fresh cadavers.Objectives: The goal was to better understand the relationship between the lumbar pedicle and the adjacent neural structures.Summary of Background data: The lumbar spine stabilization based on vertebral pedícle has been increasing to stabilize the motion segment for the treatment of several diseases. Recently with the advent of percutaneous implantation of the pedicles screws there were increasing necessity to better understand the exact anatomy of the vertebral pedicle and his relationship with the adjacent neural structures. Based on the study accomplished by Ebraheim in 1997, we decided to do anatomical study in cadavers to better understand the anatomy of that area. Methods: The size of the lumbar pedicles was assessed by measuring its sagittal and transversal diameter. The relationship of the lumbar pedicle to the neural structures was evaluated by measuring the distance between dura-mater and the pedicle medial area, the distance between the most distal area of the pedicle and the nerve root that appears under it, and, the distance between pedicle apex and the nerve root that appears over it.Results: The acquired results showed that the distance between the most distal area of the pedicle and the nerve root that appears under it, and the distance between the pedicle medial area and dura-mater, do not increase from L2 to L5, and they are in average 1,98 mm and 3,02 mm respectively. The distance between the pedicle apex and the nerve root that appears over it, increases from L2 to L5, varying from 13,64 mm to 21,62 mm in L5. The location of the spinal ganglion in relation to the pedicle has also been found, and 87% of the spinal ganglions are located in the foraminal zone. Conclusion: The size of lumbar vertebral pedicle increases from L2 to L5 in both longitudinal and transversal diameter. The traversal diameter of the pedicle is smaller than the longitudinal. The lumbar vertebral pedicle has close relationship with the root that emerges below it and the most distal portion of the pedicle is adjacent to the root and its medial border is adjacent to the dura-mater.