The ligamentum flavum, or yellow ligament, is so called because of the macroscopically slightly yellow color due to the high concentration of elastin and collagen fibers within its structure, in particular elastin makes up about 60-70% of the extracellular matrix. From an anatomical point of view the yellow ligament plays a fundamental role in metameric biomechanics because it is a significant component of the lateral and posterior wall of the spinal canal and, from a biomechanical point of view, has two fundamental characteristics: elasticity, given by the high concentration of elastin, and rigidity, conferred by collagen fibers. The combination of these two features makes the yellow ligament extremely elastic and resistant to mechanical stresses. Age and inflammatory processes cause a reduction in the concentration of elastin in the yellow ligament, with consequent changes of the collagen/ elastin ratio in favor of the second one
Citation: Landi A, Delfini R (2013) Soft Stenosis of the Lumbar Spine: Thickness vs Hypertrophy of the Ligamentum Flavum. A Pathogenetic and Molecular Point of View. J Spine 2:e111.