The basic factor that constitutes a herniated disc is disc degeneration, but the predisposing factors that lead to disc herniation have not been clearly established. However, some factors are associated with it. (i) Spinal deformity or alteration of spinal physiological curvature Spinal deformities such as symmetrical or asymmetrical displaced vertebrae, scoliosis or deformed lumbar vertebrae are predisposing factors for lumbar disc herniation. Changes in the physiological curvature of the spine predispose to intervertebral disc pathology. In scoliosis, primary scoliosis and secondary scoliosis, the intervertebral space is not only unequal in width, but also often twisted, which causes the fibrous rings to be subjected to different pressures, resulting in greater stress on the convex side of the spine and accelerated degeneration. In addition, there is unilateral sacralization of the lumbar spine, when the occurrence of disc herniation can often be multiple herniation. (B) excessive load Engaged in physical labor and weightlifting often cause early degeneration of the intervertebral disc due to excessive load. When the spine is loaded with 100kg, the normal intervertebral disc gap narrows by 1.0mm and expands laterally by 0.5mm, while when the disc degenerates, the disc compresses by 1.5mm to 2mm and expands laterally by 1mm with the same weight. When excessive lumbar loading, such as long-term bending work such as coal miners or construction workers, requires frequent bending to extract heavy objects. The strength of the posterior part of the fiber ring is measured to be less than 100kp/cm2. when the double lower extremities bending upright to extract 20kg of heavy objects, the pressure in the disc increases to more than 30kg/cm2, such as long-term in such a large disc pressure, both easy to make the rupture of the fiber ring at an early stage. (c) Lumbar puncture As early as 1935, Pease first reported that disc stenosis was found after lumbar puncture. Later, some cases were reported in which stenosis occurred after lumbar puncture or lumbar anesthesia. Most of these cases were in adolescents and even in children as young as 4 years old. Within days of the lumbar puncture, the patient had severe back pain and muscle straightening in the spine, and a series of radiographs showed a relatively rapid narrowing of the intervertebral space. The reason for this is that during the lumbar puncture, the puncture needle penetrates the fibrous ring and the nucleus pulposus leaks out of the eye of the needle. In animal studies, atypical nucleus pulposus herniation was observed after puncturing the disc with a 20-gauge needle. Six to 10 months after disc puncture in rabbits, nucleus pulposus cell hyperplasia can be found in the soft tissue of the nearby disc, forming a tumor-like jelly-like nodule. However, in recent years, since the development of discography and percutaneous lumbar discectomy, most scholars believe that the puncture needle entering the nucleus pulposus through the fibers does not lead to secondary herniation of the nucleus pulposus, especially when the puncture needle is thin and when the puncture is performed from the collateral approach. (iv) Acute injuries Acute injuries, such as lumbar back sprains, do not cause lumbar disc herniation. Clinically severe spinal fractures with vertebral compression of more than 1/3 to 1/2 also rarely rupture the disc annulus fibrosus, causing the disc to protrude into the spinal canal. Martin (1978) suggested that trauma is only a causative factor for disc herniation, and that the original lesion is a painless protrusion of the nucleus pulposus into the inner annulus fibrosus, while trauma causes further protrusion of the nucleus pulposus into the outer 5 layers of the innervated annulus fibrosus causing pain. (E) long-term vibration car and tractor drivers in the driving process, long-term sitting and bumpy state, the lumbar intervertebral discs under greater pressure. The determination of driving a car disc pressure of 0.5kp/cm2, when stepping on the clutch, the pressure increased to 1kp/cm2. long-term repeated disc elevation, can accelerate the disc degeneration or herniation. At the same time vibration also affects the nutrition of the intervertebral discs. In the test, the vibration frequency of 5Hz, with the growth of vibration time, the water content of the nucleus pulposus, inner fibrous ring and outer fibrous ring also gradually decreased, especially in the nucleus pulposus. At the same time, the oxygen tension and cellular activity in the intervertebral disc were significantly reduced. These are also the changes that occur through the effects of vibration on the microvasculature. (vi) Age The incidence of lumbar disc herniation is highest in middle age. (vii) Height The incidence of lumbar disc herniation is high in those who exceed the average height of normal men and women and have a larger lumbar spine index. (viii) Race The incidence of lumbar disc herniation is significantly lower in Indians, Eskimos, and black Africans than in other ethnic groups. (ix) Genetic factors Genetic factors may also be considered in the etiology. (x) Pregnancy The entire ligamentous system is in a state of laxity during pregnancy. The posterior longitudinal ligament expands the disc on top of the previous degeneration. The incidence of lumbar disc herniation is high after investigation of multiple pregnancies. (xi) Smoking (xii) Diabetes