The Changes of the Dimension of Intervertebral Disc,-Neural Foramen and Spinal Canal after Anterior Lumbar Interbody Fusion in the Lumbar Spine / 대한척추외과학회지

ABSTRACT

STUDY DESIGN: A prospective radiological assessment was conducted. OBJECTIVES: To analyze the changes in the heights of the intervertebral disc and neural foramen, and the diameters and areas of the dural sac and lateral recess following anterior lumbar interbody fusion and posterior fixation in lumbar degenerative disease. SUMMARY OF LITERATURE REVIEW Anterior lumbar interbody fusion distracts from the height of the intervertebral disc and neural foramen and increase the area of the spinal canal. MATERIALS AND METHODS: A mini-open anterior lumbar interbody fusion and posterior fixation was performed on 40 cases between January 1999 and March 2002. The measured factors included the height of the intervertebral disc and neural foramen, the midsagittal and lateral diameters of the dural sac, the area of the dural sac and the diameter of the lateral recess. These were measured with calipers in 1mm reconstructive computed tomography images before and 6 months after the anterior lumbar interbody fusion. The measured factors were independently taken by three different orthopaedic surgeons. RESULTS: The heights of the intervertebral disc and neural foramen were increased by means of 39.1 and 18.7% respectively. The midsagittal diameter of the dural sac was increased by a mean of 11.6% and that of the lateral dural sac decreased by a mean of 3.7%. The area of the dural sac was increased by a mean of 8.1% and the diameter of lateral recess by a mean of 26.3%. There were statistically significant increases in all the measured factors, with the exception of the lateral diameter of the dural sac. CONCLUSIONS: Anterior lumbar interbody fusion significantly increases the heights of the intervertebral disc and neural foramen, the midsagittal diameter of the dural sac, the area of the dural sac and the diameter of the lateral recess, but not the lateral diameter of the dural sac.