Lumbar disc herniation is a disease in which the nucleus pulposus ruptures under the action of external force after the degeneration of the lumbar intervertebral disc, and the main symptom is low back pain caused by stimulation or compression of nerve roots, blood vessels, spinal cord and other tissues, accompanied by radiating pain in the lower limbs. Lumbar disc herniation is a common disease, and its incidence accounts for about 15% of outpatients with lumbar and leg pain, and many patients with lumbar pain and leg pain are diagnosed with lumbar disc herniation after clinical examination. Many patients start with simple back pain and only later develop typical disc herniation, so the incidence of lumbar disc herniation is more than the general clinical statistics. The disease is mostly seen in strong manual workers, more men than women, the ratio of men to women is 10-15:1; the age of onset is mostly in the 20-50 years old, only 6% under 20 years old; about 70% have a history of trauma; from the onset of the site, the disease occurs in the lumbar 4 to lumbar 5 and lumbar 5 to sacral 1 two segments, accounting for about 90%. The posterior longitudinal ligament is uninterrupted throughout the length of the spine, but since the first lumbar vertebrae, the posterior longitudinal ligament gradually narrows to the fifth lumbar vertebra and the first sacral vertebra, the width is only equal to half of the original, the lumbosacral part is the part that bears the greatest force and static force, so the narrowing of the posterior longitudinal ligament has caused a natural structural weakness, and the nucleus pulposus tends to protrude to the rear on both sides. The causes of this disease are both endogenous and exogenous. The endogenous cause is degeneration of the intervertebral disc itself or developmental defects of the disc; the exogenous cause is injury, strain and cold, etc. According to relevant statistics, the majority of patients have low back pain, about 50% of patients have low back pain followed by leg pain, about 33% of patients have low back pain and leg pain at the same time, about 17% of patients have leg pain followed by low back pain. Low back pain is mainly due to the degenerative protrusion of the intervertebral disc, which stimulates the outer fibrous ring and the sinus nerve fibers in the posterior longitudinal ligament, which consists of 2/3 of sympathetic nerves and 1/3 of somatic nerves, and can stimulate the dura mater to produce duralgia if the disc is herniated. The pain lasts from a few days to several years and is located in the lower back and lumbosacral region. This type of pain is felt deeper and manifests as limited or widespread dull pain in the back with slow onset and inaccurate localization, aggravated by activity and relieved by bed rest; and the symptoms of low back pain rarely affect life and work completely. When the lumbar intervertebral disc protrudes suddenly, the acute onset of low back pain, low back pain and muscle spasm, lumbar activities are obviously restricted, low back pain is unbearable, unable to work, or even daily life can not take care of themselves, must be bed rest, such patients may have a sudden twisting of the waist or lifting heavy objects with little force and other triggers, this is mainly due to ischemic radiculitis, that is, the sudden protrusion of the nucleus pulposus compressing the nerve root, resulting in the root blood vessels This is mainly due to ischemic radiculitis, that is, the sudden protrusion of the nucleus pulposus to compress the nerve root, resulting in pressure on the root blood vessels and presenting a series of changes such as ischemia, bruising, hypoxia and edema, and can last for several days to weeks. (ii) Radiating pain of the lower extremity 1. Sudden or gradual onset and progressive aggravation of radiating sharp pain, dull pain, persistent or intermittent pain, radiating from the lumbar hip to the posterior (lateral) thigh, N fossa, lateral calf, heel, dorsal foot or small toe. Individual patients may have reverse radiating pain, which may occur simultaneously with lumbago or before or after lumbago. 2.Some of the pain can be aggravated by activities or increase in abdominal pressure (coughing, sneezing or forceful defecation, etc.) in a certain posture or suddenly appear as electric shock-like radiating pain, and the pain disappears immediately after the stimulation stops; some of the pain sites are more extensive, or even difficult to determine the exact location, their response to stimulation is slow, and the pain disappears incompletely, so patients have both continuous pain and sudden aggravation. 3. Most patients start to have low back pain, which is soon relieved and radiating pain appears in the lower limbs. This is because when the nucleus pulposus protrudes further, the fiber ring which was under tension will rupture, so that the tension of the nerve fibers on it will be reduced, so the pain will be relieved; also, the leg pain will be aggravated because the nucleus pulposus protrudes further and directly presses the nerve root through the posterior longitudinal ligament. In mild cases, the pain is radiating from the waist to the thigh and the back of the calf to the foot, which is generally tolerable; in severe cases, the pain is electric shock-like pain from the waist to the foot, and is accompanied by numbness. 4, the light pain can still walk, but the gait is unstable, limping, the waist more to take a forward leaning shape or to hold the waist to relieve the tension stress on the sciatic nerve; heavy people need to bed rest and prefer to take a bent hip flexion knee side lying position. Any factors that increase abdominal pressure can make radiating pain worse. As the flexion of the neck can increase the stimulation of the spinal nerve through the pulling of the dural sac, so that the head and neck like to supine position. 5, radiating pain is mostly on one side, very few patients can have bilateral lower extremity radiating pain or alternating bilateral lower extremity radiating pain, seen in patients with central type giant protrusion. 6.A few patients may have no obvious pain in the lower extremities at the beginning of the disease, or only a slight discomfort or heaviness in the lower extremities, and occasional transient pain during lumbar activities. 7.The scope and degree of pain correlate with the degree of sciatic nerve compression: with mild compression or stimulation, pain in the buttocks appears, and the pain is slightly mild; with moderate compression or stimulation, pain in the buttocks, femur and calf appears, and the pain is more severe; with severe compression or stimulation, pain from the buttocks to the foot appears, and the pain is more severe. (iii) Pain in the lower abdomen or anterior (medial) thigh In patients with high lumbar disc herniation, the nerve roots of lumbar 1 to lumbar 4 are involved and pain in the area innervated by the nerve roots (lower abdomen, groin area) or anterior medial thigh occurs. In addition, some low lumbar disc herniations (L4-5 and L5-S1) may also present with lower abdominal pain, pain in the inguinal region or perineal pain, which is mostly referred pain and has some localization diagnostic significance: pain in the lateral inguinal region suggests L4-5 disc herniation; pain in the medial inguinal region or perineal pain suggests L5-S1 disc herniation. (iv) Intermittent claudication When walking, patients experience low back pain or aggravated radiating pain or numbness on the affected side as the distance increases, and claudication can occur in severe cases, while this distance is only ten meters or so in short cases and hundreds of meters in most cases, and the symptoms can be relieved by taking a squatting or sitting position to rest for a period of time, and the symptoms reappear when walking again. This is because the intervertebral disc tissue compresses the nerve roots or the volume of the spinal canal decreases, causing nerve root congestion, edema and inflammatory reaction, and when walking the vertebral vein plexus that is blocked in the spinal canal gradually expands, increasing the compression of the nerve roots and causing hypoxia and symptoms. This is most obvious in the elderly, because lumbar disc herniation in the elderly is mostly accompanied by varying degrees of lumbar spinal canal stenosis, which can easily cause intermittent claudication, and the symptoms are obvious. (v) Muscle paralysis A small number of patients with lumbar disc herniation can develop nerve paralysis and muscle paralysis when the nerve root compression is severe and prolonged. The more common ones are lumbar 4 and 5 disc herniation, lumbar 5 nerve root paralysis, paralysis of tibialis anterior, fibular long and short muscles, [long and long extensor muscles and toe long extensor muscles, foot drop, of which [long extensor muscle paralysis, [toe can not be dorsal extension is most common; lumbar 5 to sacral 1 disc herniation, sacral 1 nerve root involvement, gastrocnemius and flounder muscle strength loss, but calf triceps paralysis is rare. The acute protrusion of intervertebral disc tissue due to a sharp increase in abdominal pressure in individual mothers during childbirth can compress the nerve roots in severe cases, manifesting as sudden onset of muscle paralysis confined to the innervated area of the common peroneal nerve after delivery without significant pain, called maternal birth palsy to distinguish it from neonatal birth palsy. (vi) Numbness Patients with a longer course of disease often have subjective numbness. The numbness sensory area is distributed in the area of lumbosacral nerve root involvement, mostly limited to the lower leg, lateral dorsum of the foot, heel and lateral plantar aspect of the foot, and only 5% of the patients simply show numbness without pain, which is mainly due to the stimulation of proprioceptive and tactile fibers within the spinal nerve root. (g) Cauda equina syndrome Central lumbar disc herniation, when the protrusion is huge, often compresses the cauda equina nerve below the protrusion plane. The cauda equina usually includes the nerve roots from lumbar 3 to caudal 1, so the efferent and/or afferent nerve fibers innervating the pelvic viscera and/or perineum are lesioned and cone syndrome occurs. It is clinically difficult to distinguish cauda equina damage from conus damage, since cauda equina lesions usually affect not only the sacral segments but also a large number of lumbosacral nerve fibers. Early manifestations include severe bilateral sciatica, numbness in the perineum, and weakness in defecation and urination. Sometimes the sciatica may alternate, sometimes left and sometimes right, and then the sciatica disappears and the patient shows incomplete paralysis of both lower extremities, such as inability to extend the toes or foot drop, as well as loss of pain in the posterior and lateral perineum of both lower extremities, and dysfunction of urination and defecation, mostly manifested as acute urinary retention and uncontrolled defecation. In female patients there may be pseudo-incontinence and in male patients there is functional impotence. (H), spinal cone syndrome When a high lumbar disc is herniated, the lesions of sacral spinal cord sacral 3-5 segments and caudal medullary lumbar segments manifest as a typical syndrome, with somatic symptoms including perineal and perianal skin sensory deficit. If sacral segment 2 is involved, there will be numbness in the posterior thighs, which manifests as numbness in the saddle area. There is muscle weakness at the pelvic outlet, including the external anal sphincter, bladder sphincter and the sciatic cavernous and bulbocavernosus muscles. The bulbocavernosus reflex can be induced by stimulation of the glans penis, which is manifested by contraction of the internal urethra or contraction of the external anal sphincter after palpation of the scrotum. Signs due to damage to the preganglionic parasympathetic nerves include flaccid paralysis of the bladder sphincter (no bladder filling sensation, no pain) and inability to void spontaneously. Due to the corresponding loss of control of the anal sphincter, fecal incontinence during increased abdominal pressure, inability to defecate on one’s own, complete loss of penile erection and ejaculatory ability. (ix), coldness of the affected limbs A few patients feel coldness in the lower limbs, due to pain in the affected limbs reflexively causing sympathetic vasoconstriction, or due to stimulation of sympathetic nerve fibers in the paravertebral area, causing contraction of the vascular walls of the lower limbs. The temperature of the affected limb may be low, especially in the toes. This phenomenon of decreased skin temperature is more obvious with the compression of the sacral 1 nerve root than the lumbar 5 nerve root. However, the dorsalis pedis artery pulsation is normal, and some patients have the phenomenon of sweating of the affected limb. (X), coccygeal pain Very few patients may have coccygeal pain, mostly caused by the migration of the herniated intervertebral disc tissue into the sacral canal, and also caused by anatomical variation of the lumbar spine or lumbosacral plexus stimulating the nerves. (xi), calf edema Very few patients may have edema of the affected calf, which may be related to the nerve roots being mechanically and chemically stimulated by local sterile inflammation, adhesions and edema, affecting the conduction function of sympathetic nerves and causing the corresponding vascular nerve dysfunction in the lower limbs.