Lumbar spinal stenosis and spondylosis associated with amyloid deposition in the ligamentum flavum.

Thickening (hypertrophy) of the ligamentum flavium is one of the many anatomical abnormalities associated with lumbar stenosis and spondylosis. In twelve of 97 patients who had decompression laminectomy the thickened ligamentum flavum contained abundant amyloid in both light and electronmicroscopic preparations. Since the cases were collected over a period of two years from the practice of a single neurosurgeon, its appears to be a common finding, and is age related. In all cases CT and MR scans showed a prominent ligamentum flavum. Nevertheless, there was not a well-defined clinicopathological correlation. The pathogenesis is not clear.