The ligamentum flavum connects adjacent vertebral laminae throughout the spinal column from C2 to S1, forming a significant portion of the posterior wall of the spinal canal. Its high elastin content, the highest of any ligament in the body at approximately 80 percent, gives it a yellow colour and allows it to maintain resting tension without buckling, which is critical for preventing it from folding into the spinal canal during extension.
| Origin | Anterior surface of the lamina of each vertebra |
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| Insertion | Posterior surface of the lamina of the vertebra below |
| Actions | Resists flexion of the spine; maintains constant tension on the spinal column; forms part of the posterior wall of the spinal canal |
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Ligamentum flavum hypertrophy is one of the primary causes of lumbar spinal stenosis in older adults, contributing to central canal and lateral recess narrowing that produces neurogenic claudication. The hypertrophied ligament can compress the cauda equina and nerve roots, producing leg pain, numbness, and weakness with walking that is relieved by sitting or spinal flexion. Surgical decompression by laminectomy and flavectomy directly addresses the hypertrophied ligament.
Age-related thickening of the ligament reducing the spinal canal diameter and compressing neural structures, producing neurogenic claudication with walking that is relieved by sitting, managed with decompressive surgery in severe or refractory cases.
