Morphological Changes in the Ligamentum Flavum in Degenerative Lumbar Canal Stenosis: A Prospective, Comparative Study

ABSTRACT

Methods@#Forty patients were prospectively recruited and divided into two groups group 1 included 20 patients with degenerative LCS aged >55 years and group 2 included patients with LDH aged <35 years. The ligament flava were collected during the patients’ surgery. The features noted on histopathological examination included the fibrosis score, the loss of elastic fibers, calcification, chondroid metaplasia, mucinous degeneration, vascularization, long septa, clefts, granulation tissue, and ganglion-like cysts. The features noted on electron microscopic examination included the elastic fiber thickness, the quality of elastic fibers, the elasticcollagen ratio, calcification, melanin fibers, remnants of necrotic cells, and electron-dense material in the LF. All parameters were compared between group 1 and group 2. @*Results@#On histopathological examination, the two groups exhibited significant differences regarding three parameters chondroid metaplasia, long septa, and ganglion-like cysts. On electron microscopy examination, significant differences were observed between the two groups regarding two parameters the quality of elastic fibers and the elasticcollagen ratio. @*Conclusions@#Characteristic morphological changes may be noted on histopathological and electron microscopic examination that mark the degenerative changes in the LF that contribute to the occurrence and pathogenesis of degenerative LCS.