Ligamentum flavum thickening refers to hypertrophy of the ligamentum flavum in the posterior aspect of the spinal canal, which causes compression of the spinal cord or nerve roots. Ligamentum flavum thickening is often seen in imaging reports, and the presence of ligamentum flavum thickening is clearly identified in such patients after an enhanced CT or MRI. The ligamentum flavum is a longitudinal ligament located posterior to the spinal canal and is present between the adjacent vertebral arches. The main function of the ligamentum flavum is to strengthen the stability of the posterior column of the spine. The ligamentum flavum has some elasticity, so it is very important for the motor function of the spine. If the patient sits or stands with his head down for a long time, or has a bad posture, it may lead to damage or overgrowth of the ligamentum flavum. At this time, due to the yellow ligament hypertrophy forward compression of the spinal cord or nerve roots, which in turn causes pain in the low back, or a series of symptoms such as radiating pain in the lower extremities.