Plain Radiological Measurement of Relationships Between Intervertebral Disc Space and Spinous Process

Kim, Dae Gyu; Oh, Suck Jun; Jho, Hae Dong; Yoo, Young Rak; Kim, Nam Kyu; Chung, Hwan Yung

Abstract

The mean values of the height, depth and lateral shifting of the spinous processes and the height of the intervertebral disc spaces of 100 patients were measured in the lumbar region. The application of microsurgical techniques in the operation for lumbar disc herniation clearly reduced the overall surgical trauma suffered by patient, but the spinous process might disturb the insertional course and multidirectional activities of the pituitary forceps due to a very small skin incision. The purpose of this study was to prove the relationships between intervertebral disc space and spinous process in the lumbar region. The results were as follows; 1) The height of the intervertebral disc space from L3-4 to L5-S1 intervertebral disc space was 12.63mm, 12.57mm and 11.71mm respectively. 2) The depth of the spinous process from L3 to L5 was 28.87mm, 27.87mm and 23.97mm respectively. 3) The lateral shifting of the spinous process from midline to the right side was 4.39mm, 4.35mm and 4.01mm at L3, L4 and L5 spinous process respectively and to the left side was 3.61mm, 3.70mm and 3.69mm at L3, L4 and L5 spinous process respectively. Conclusively, the lower part of the spinous process was overlapped above the intervertebral disc space at L3-4, L4-5 and L5-S1 intervertebral disc space. About 4mm of the lateral shifting of the spinous process was protruded to both right and left side in the insertional course(about 2-3cm) of the pituitary forceps. The spinous process might disturb the multidirectional activities and perpendicular insertion of the pituitary forceps. So, the removal of the spinous process to the midline was recommended to perform the complete removal of disc materials in microlumbar discectomy.