A clinical study on segmental instability of the lumbar spine / 中华物理医学与康复杂志

ABSTRACT

Objective To explore factors related to the development of segmental instabilities in lumbar spine. Methods Fifty-seven patients with lumbar segment instabilities at L 4～5 were selected as illness group, 22 patients with facetectomy at L 4～5 as post-operation control group, and 19 healthy subjects as normal control. X-ray plain films were taken in sagittal,flexion and extension positions. Computed tomographic scans were taken to define the axial morphology of the facet joint. Magnetic resonance scans were taken to describe disc degeneration of 36 patients in illness group. Results The facet joint was oriented sagittally in the forward translation patients in flexion. The disc degeneration was slight in the rotational instability patients. The patients with total facetectomy exited forward translation in flexion. Conclusion A more sagittally oriented facet and disc degeneration are associated with forward translation in flexion and may be the cause of degenerative spondylolisthesis, whereas ligament failure is associated with rotational instability.