Ligamentum flavum is one of the important supporting ligaments in spinal canal to maintain the stability of spinal structure. Lumbar ligamentum flavum hypertrophy (LFH) is a chronic pathological process that changes the nature and structure of the ligamentum flavum due to aging, obesity, mechanical stress, inflammation and other reasons. The hypertrophic ligamentum flavum compresses the spinal cord or nerve roots and produces a series of symptoms, such as lower back pain or lower limb pain and numbness, which is an important cause of lumbar spinal stenosis. There are many reports on the etiology and mechanism of LFH, but there is a lack of corresponding summary and induction. From the perspective of etiology and pathological mechanism, this paper reviews the relevant literature about lumbar LFH in recent 5 years, discusses and summarizes the etiology and mechanism of LFH, and expounds the research status of LFH and targeted molecular intervention in LFH.

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