1, postural changes: Patients with mild disc herniation often do not have obvious abnormalities in their posture and action, and only feel varying degrees of pain or discomfort such as soreness and weakness. However, the more severe herniation can cause changes in the shape of the spine and abnormal function of the limbs. This change is especially obvious with lumbar disc herniation, and pathological posture such as prostration of the arms, bending over, torso distortion, limited stride or limp. 2, spinal changes: under normal circumstances, the cervical and lumbar vertebrae have a certain arc of physiological convexity, but when the disc herniation occurs on the basis of degenerative changes, the physiological flexion is reduced or straightened, the cervical vertebrae can appear posterior convex deformation, and the lumbar vertebrae are often combined with scoliosis while the axis is straight. This is a result of the pain caused by the herniated disc tissue compressing the nerve roots, and the patient must instinctively adopt self-protective positions that help to reduce the pressure on the nerve roots and reduce the tension of the nerve roots being pushed or pulled to relieve the pain. The loss of physiological anterior convexity of the spine straightens the axis, widens the posterior portion of the intervertebral space, and weakens the extrusion pressure on the intervertebral disc; it also increases the tension of the posterior longitudinal ligament, preventing excessive herniation of the disc tissue into the spinal canal and partial return of the nucleus pulposus into the intervertebral space; the straightening of the vertebral axis also increases the tension of the ligamentum flavum. All of these changes increase the volume of the spinal canal to reduce the degree of nerve root compression and relieve pain symptoms. The mechanism that causes scoliosis, like spinal straightening, is to change the close relationship between the herniated disc and the adjacent nerve root. On the contrary, if the herniated disc is located in the upper part of the nerve root, that is, the shoulder, the spine is bent to the healthy side and convex to the affected side, so as to reduce the degree of extrusion of the nerve root by the disc, reduce the tension of the nerve root, and achieve the purpose of relieving the symptoms. 3, spinal activity is limited: about 90% of patients with disc herniation have varying degrees of spinal activity limitation, standing, walking, posterior extension, weight bearing and other activities in all directions are affected to some extent, but especially in posterior extension is more obvious limitation. This is because the tension of the posterior longitudinal ligament is increased in forward flexion, the posterior part of the vertebral space is widened, and the compression of the nerve roots is reduced by a certain degree of forward displacement of the herniated nucleus pulposus. However, in posterior extension, the posterior part of the intervertebral space becomes narrower, the posterior longitudinal ligament relaxes, and the herniated nucleus pulposus moves backward, which increases the compression and stimulation of the nerve root. 4, pressure pain and radiological pain: 83% of patients with disc herniation have pressure pain next to the spinous process of the diseased intervertebral space, and cervical disc herniation can be radiated to the upper extremity, while lumbar disc herniation radiates to the hip and lower extremity along the sciatic nerve distribution area. This has important implications for diagnosis and localization. Paravertebral pressure pain is caused by the herniated disc squeezing the nerve root toward the ligamentum flavum, and if pressure is applied to the ligamentum flavum from the paravertebral area, the nerve root is squeezed anteriorly and posteriorly, resulting in pain and radiating pain. Localized paraspinal pain is caused by irritation of the spinal nerve roots with increased sensitivity. Radicular pain is caused by the stimulation of the brachial plexus nerve and sciatic nerve formed by the anterior branch nerve fibers, because these irritated nerves become more sensitive, and sometimes the compression of the branches of the sciatic nerve can also cause pain. 5, muscle atrophy: some patients with severe disc herniation often have muscle atrophy and muscle office decline changes. This is, on the one hand, due to long-term compression of the nerve roots caused by the damage to the lower motor units secondary to neurotrophic atrophy. On the other hand, it is a disuse atrophy due to long-term pain relief by reducing the movement of the affected limb. Muscle atrophy is mainly seen in lumbosacral nerve damage caused by lumbar disc herniation. 6. Hyperalgesia: In addition to subjective numbness of the limbs or fingers (toes), patients with disc herniation also have a dull nociceptive response when the skin sensation of the damaged innervation area is pricked with a needle. If the central disc herniation compresses the spinal cord, sensory impairment may not only occur in the upper extremities, but also in the lower extremities and even in the trunk. 7, tendon reflex abnormalities: tendon reflexes in patients with disc herniation often appear weakened, disappeared or hyperactive and other abnormalities, such as abnormal biceps reflexes suggesting cervical 5 nerve involvement; abnormal triceps reflexes suggesting lumbar 4 nerve involvement; abnormal ankle reflexes suggesting sacral 1 nerve compression, etc. 8, cauda equina symptoms: mainly seen in the posterior central type and the central paracentral type of medullary nucleus accumbens (prolapse), so it is rare clinically. Its main manifestations are numbness and tingling in the perineum, defecation and urination disorders, impotence (male), and symptoms of sciatic nerve involvement in both lower extremities. In severe cases, symptoms such as loss of control of urination and defecation and incomplete paralysis of both lower limbs may occur. 9. Lower abdominal pain or anterolateral thigh pain: In high lumbar disc herniation, when the lumbar 2, 3 and 4 nerve roots are involved, there is pain in the groin area of the lower abdomen or anteromedial thigh in the area innervated by the nerve roots. In addition, some patients with low lumbar disc herniation may also present with pain in the inguinal region or anterior medial thigh. Those with lumbar 3 to 4 disc herniation have pain in the inguinal region or anterior medial thigh in 1/3 of them. The rate of occurrence in those with disc herniation between lumbar 4 to 5 and lumbar 5 to sacral 1 is almost equal. This kind of pain is mostly referred pain. 10, low skin temperature of the affected limb: similar to cold sensation of the limb, also due to pain in the affected limb, reflexively causing sympathetic vasoconstriction. Or due to provocation of the sympathetic nerve fibers in the paravertebral area, sciatica is triggered and the skin temperature of the lower legs and toes is lowered, especially in the toes. This hypothermia is more pronounced in those with sacral 1 nerve root compression than in those with lumbar 5 nerve root compression. On the contrary, after medullary nucleus removal, feverish sensation will appear in the limbs. 11.Other: Depending on the location of the compressed spinal nerve roots, the degree of compression, the extent of involvement of adjacent tissues and other factors, some rare symptoms may appear, such as excessive sweating, swelling, sacrococcygeal pain and radiating pain in the knee.