The causes of lumbar disc herniation are caused by many factors.

Lumbar disc herniation is common among middle-aged and elderly people nowadays, and has become increasingly younger in recent years. The pain caused by lumbar disc herniation is very obvious. People who often exert excessive force or sit frequently are prone to lumbar disc herniation.

1. Main causes

It is well known that the lumbar intervertebral disc is subjected to strong compressive stress during the load and movement of the spine. After about 20 years of age, the intervertebral disc begins to degenerate, which becomes the basic cause of lumbar disc herniation. In addition, lumbar disc herniation is associated with the following factors:

(1) Trauma: Observations of clinical cases have shown that trauma is an important factor in intervertebral disc herniation, especially in children and adolescents. When the spine is lightly loaded and rotated rapidly, horizontal rupture of the annulus fibrosus may occur, while compressive stress mainly causes rupture of the cartilage endplate. Some people also believe that trauma is only a triggering factor for intervertebral disc herniation. The original lesion is that the painless nucleus pulposus protrudes into the inner annulus fibrosus, and trauma causes the nucleus pulposus to further protrude to the outer annulus fibrosus which is innervated by nerves, thus causing pain.

(2) Occupation: Occupation is closely related to lumbar disc herniation. For example, car and tractor drivers are in a sitting and bumpy state for a long time, so when driving a car, the pressure in the intervertebral disc is high, which can reach 0.5kPa/cm2. When the clutch is pressed, the pressure can increase to 1kPa/cm2, which can easily cause lumbar disc herniation. People who engage in heavy physical labor and weightlifting are more likely to suffer from intervertebral disc degeneration due to excessive load. When bending over and lifting a 20kg weight, the pressure inside the intervertebral disc can increase to more than 30kPa/cm2.

(3) Genetic factors: There are reports of familial incidence of lumbar disc herniation, but there is little data in China. In addition, statistics show that the incidence rate among Indians, African blacks and Inuit is significantly lower than that of other ethnic groups. The reasons for this need further study.

2. Predisposing factors

In addition to the above-mentioned main causes, namely, degenerative changes of the intervertebral disc, various inducing factors also play an important role. For example, some factors that slightly increase abdominal pressure can cause the nucleus pulposus to protrude. The main reason is that, on the basis of intervertebral disc degeneration, some factors that can induce a sudden increase in intervertebral space pressure cause the free nucleus pulposus to pass through the degenerated and thinned annulus fibrosus into the front of the vertebral canal or pass through the vertebral lamina to invade the edge of the vertebral body. The predisposing factors are generally the following:

(1) Increased abdominal pressure: Clinically, about one-third of cases have clear factors that increase abdominal pressure before the onset of the disease, such as severe coughing, sneezing, holding the breath, straining to defecate, and even "empty bowel movements", which can increase abdominal pressure and destroy the balance between the vertebrae and the spinal canal.

(2) Improper waist posture: Whether in sleep or in daily life or work, when the waist is in a flexed position, if it is suddenly rotated, it can easily induce nucleus pulposus herniation. In fact, in this position, the pressure in the intervertebral space is also high, which can easily cause the nucleus pulposus to protrude backwards.