Abstract
Open discectomy is one of usual treatment for herniated intervertebral disc. We may expect the reduction of height of intervertebral disc due to decreased volume by partial resection of herniated disc. But the effect of decreased height of intervertebral disc space to posterior joint and spinal canal has not been identified, and the correlation between the amount of reduced height and the changes of range of motion has been undetermined. Thus, we analyzed radiologic changes of disc height and segmental motion by the flexion-extension view in 20 patients who had undergone discetomy for prolapsed intervertebral disc from June 1989 to January 1991 who could be followed up for 3 years or more. As a result, lumbar discetomy associates with 1) significant decrement of disc height (average 14%), 2) decreased disc motion of involved segment without hypermobility (average 34%), 3) hypermobility of adjacent segment, 4) and posterior facet overriding consistent with recurred low back pain.