Lumbar disc herniation is due to degeneration and injury of the intervertebral disc tissue, rupture of the fibrous ring, protrusion of the nucleus pulposus tissue from the ruptured fibrous ring to the posterior, compression of the spinal nerve root or cauda equina nerve, producing lower back pain and sciatica of the lower limbs, is one of the main causes of clinical sciatica, accounting for about 20% of patients with low back pain, occurs in young adults, and is common in manual laborers. It occurs most often in the lumbar 4 and 5 or lumbar 5 and sacral l intervertebral spaces. The structure is a rupture of the fibrous ring at a weak point resulting in the protrusion of the nucleus pulposus and the reduction of water in the nucleus pulposus, which eventually narrows the lumbar spinal canal and neural tube, and the disc itself degenerates into a fibrocartilaginous entity, making the lumbar intervertebral space relatively fixed. When the degenerated disc is subjected to stress, the high pressure stress is distributed in the inner fibrous annulus and the tension is mainly concentrated in the outer fibrous annulus, and the degenerated disc produces compression, together with the gradual narrowing of the posterior longitudinal ligament in the anatomical structure to form weakness of the lumbar segment and weakness of the posterior lateral aspect of the fibrous annulus, so the compressed disc tissue tends to form herniation to the lateral side. And rotational load is generated during trauma or incorrect carrying posture. Other factors are: abnormal stress due to congenital anomalies of the lumbosacral spine, occupational increased disc loading and sudden stress, and laxity of the posterior longitudinal ligament during pregnancy. Pathology】 Early degeneration manifests as horizontal tears of the fibrous ring, which later develop into large radial tears and go from superficial to deep to the nucleus pulposus, eventually leading to complete rupture of the fibrous ring, absorption of water and proteoglycans in the nucleus pulposus, and filling of the intervertebral space with fibrous tissue. The collagen fibers of the nucleus pulposus, cartilage plate and ruptured fibers compress the nerve roots and cauda equina, causing neurological symptoms with nerve congestion, edema and inflammatory reaction. The pathological types can be classified according to the relationship between the annulus fibrosus and the nucleus pulposus and the displacement of the disc tissue: 1, annular bulge of the vascular ring, the bulge is located between the adjacent vertebrae, the annulus fibrosus is intact, and there are no symptoms of nerve root compression. 2, the dimensional ring limited bulge, the fiber ring is intact, the nucleus pulposus is not herniated, there are clinical symptoms. 3, disc protrusion, the nucleus pulposus protrudes from the weak fibrous ring, producing severe symptoms. 4, disc prolapse, the nucleus pulposus prolapses through a completely ruptured fibrous ring to below the posterior longitudinal ligament, and the prolapsed nucleus pulposus may be located at the shoulder of the nerve root, in the axilla, or in the anterior middle of the spinal canal. 5. In a dissociated disc, the nucleus pulposus is free through the completely ruptured fibers and posterior longitudinal ligament in the spinal canal or in the subarachnoid space within the dura, compressing the nerve root or cauda equina. Some people divide the discs into central and peripheral types according to the direction of disc tissue protrusion and clinical symptoms. The former protrudes to the posterior side to compress the tissue in the spinal canal, such as the cauda equina nerve or spinal cord, while the latter forms an entrapment, and conservative treatment can only relieve the symptoms. Clinical manifestations】 1. The symptoms are mainly low back and leg pain, numbness, intermittent claudication and cauda equina syndrome, etc. Low back and leg pain: first low back pain and then leg pain, or both at the same time, or first leg pain and then low back pain. The duration of pain varies from a few days to several years. The pain is slow in onset, with limited or widespread dull pain in the low back, aggravated by activity and relieved by bed rest. Leg pain is mostly caused by the stimulation of sciatic nerve, with radicular radiating pain from the lumbosacral region, posterior hip, posterior lateral thigh, lateral calf to the heel or back of the foot, and the patient mostly adopts the flexed hip and knee position to relieve the pain. Numbness: Numbness or hypesthesia in the sciatic nerve distribution area may occur with repeated attacks or prolonged delay. Intermittent claudication: due to muscle weakness and muscle atrophy, pain or numbness of the affected limb appears after walking a certain distance and gradually worsens. Cauda equina syndrome: Those with central lumbar disc herniation may have sciatica and numbness in the perineal region alternating between the left and right sides. Severe cases produce sphincter dysfunction. 2, signs mainly include abnormal lumbar spine posture, pressure pain, lumbar spine movement, muscle strength change and muscle atrophy, hypesthesia, tendon reflex change and nerve root irritation sign. Lumbar spine posture: physiological bending disappears, scoliosis, to relieve the symptoms of nerve root compression. Pressure pain: paravertebral pressure pain and radiation to the lower extremities, increased abdominal pressure, such as coughing, supine sitting, and bowel movement when the pain is aggravated. Lumbar spine motion: limited lumbar lateral bending, limited posterior extension, and limited forward flexion in the late stage may occur. Muscle strength changes and muscle atrophy: muscle strength loss and muscle atrophy of the affected innervated muscles, such as the anterior tibial muscles, the long thumb extensors, and the long toe extensors. Disc herniation occurred at lumbar 4 and 5, weakening of the dorsal toe extensors, and atrophy of the triceps calf muscle occurred at lumbar 5 sacral 1. Hypesthesia: sensory disturbances are distributed according to the innervation of the affected nerve roots and are evident in a single nerve distribution area. Altered tendon reflexes: weakened or absent knee reflexes when occurring at lumbar 3 and 4 intervertebral spaces, and weakened or absent Achilles reflexes when lumbar 5 sacral 1 is herniated. Nerve root stimulation signs: positive straight leg raise test and strengthening test, positive LaSeque’s sign. Diagnosis】 Preliminary diagnosis can be made based on the medical history and clinical manifestations. Special examination methods can be of great help in diagnosis, such as conventional lumbar spine plain film, spinal canal imaging, lumbar discography, CT scan, MRI, ultrasound diagnosis, etc. Treatment】 1.Surgical treatment can cure most of them by non-surgical treatment. The methods include traction, massage, epidural corticosteroid injection therapy, etc. The purpose is to change the relative position of the disc tissue and the compressed nerve, reduce the compression of the nerve root by the protruding tissue, loosen the adhesion of the nerve root, and release the symptoms. Prolonged bed rest is necessary after comprehensive treatment. Nucleolysis therapy using papaya rennet and collagenase intervertebral injection is indeed an effective treatment method, and its efficacy has been reported to be slightly stronger than that of surgical treatment. 2, surgical treatment through the posterior resection of part of the vertebral plate and articular protrusion or through the intervertebral space to remove the intervertebral disc, the central type of cases to perform the whole laminectomy, intervertebral disc removal efficacy is certain. In recent years, the development of percutaneous microdiscectomy has the advantages of less trauma, less damage to the stability of the spine, but has the disadvantage of incomplete excision, such as a detailed pathological diagnosis before surgery, the reliability of the efficacy of patients with mild lesions and age is still worth advocating.