1.What is lumbar disc herniation? Lumbar disc herniation, also known as nucleus pulposus herniation (or prolapse), or lumbar disc fibrous ring rupture disease, is a more common clinical lumbar pain, mainly due to the lumbar disc parts (nucleus pulposus, fibrous ring and cartilage) of different degrees of degenerative changes, under the action of external factors, the intervertebral disc fibrous ring rupture, the nucleus pulposus tissue from the rupture protrusion (or prolapse) in the back or spinal canal, resulting in The adjacent tissues, nerves, spinal cord, etc. suffer from irritation or compression, thus producing lumbar pain with or without a series of clinical symptoms such as numbness, pain and weakness of one or both lower limbs. 2, the clinical manifestations of lumbar disc herniation? The typical symptoms of lumbar disc herniation are lumbar pain and symptoms such as radioactive numbness, pain and weakness in one or both legs. Due to the differences in the location, size, canal diameter, body state and individual sensitivity of the herniated nucleus pulposus, there are certain differences in clinical manifestations, mainly as follows: (1) lumbar pain: more than 95% of patients with lumbar disc herniation have this symptom. Patients feel persistent dull pain in the lumbar region, which is relieved when lying down and intensified when standing up, but is generally tolerable and can be moderately active or walking slowly. In the acute stage, the pain may be severe and unbearable, and it may affect life and work seriously, and cannot be relieved even by bed rest. (2) Radiating pain of lower limbs: 80% of patients have this syndrome, which often appears after the lumbar pain is reduced or disappears. The pain or numbness is radiating from the waist to the thighs and calves, sometimes up to the bottom of the feet. In severe cases, it can be a severe electric shock-like pain from the waist to the foot, and is mostly accompanied by numbness and weakness. Those with mild pain can walk with a limp; those with severe pain need to rest in bed, preferring flexion of the waist, hip and knee position. (3) Lower limb numbness, cold sensation and intermittent claudication: lower limb numbness is mostly accompanied by pain, a few patients can show simple numbness, and a few patients feel cold and chilly in the lower limbs. This is mainly due to the stimulation of sympathetic nerve fibers in the spinal canal. The mechanism and clinical manifestations of intermittent claudication are similar to those of lumbar spinal stenosis, mainly because the pathological and physiological symptoms of secondary lumbar spinal stenosis can occur in the case of nucleus pulposus herniation. (4) Cauda equina symptoms: mainly seen in central type of nucleus pulposus prolapse, which is less common clinically. Numbness and tingling in the perineum and dysfunction of urination and defecation may occur. Urinary incontinence may occur in women and impotence in men. In severe cases, loss of control of urination and defecation and incomplete paralysis of both lower limbs may occur. 3.What are the signs of lumbar disc herniation? The signs of lumbar disc herniation are mainly the lumbar and spinal signs and nerve root signs. (1) Lumbar and spinal signs: ① Scoliosis: the patient’s spine is mostly scoliosis, and scoliosis is a protective measure to keep the nerve away from the herniation, relieve pressure, and reduce pain. ② Change in lumbar curvature: the physiological anterior convexity of the lumbar spine disappears and may even be convex backwards, which is also a protective measure to relieve pain. ③ Restriction of spinal movement: The movement of the spine in all directions, such as posterior extension, forward flexion, lateral bending and rotation, is restricted to varying degrees. (iv) Pressure point: pressure pain may be present at about 0.5 cm of the paraspinal aspect of lumbar disc herniation and may radiate to the lower limbs, with the affected side being obvious. (2) Nerve root signs: ① Straight leg elevation test and strengthening test: its positive rate is more than 90%. Ask the patient to lie on his back with both lower limbs straightened, and the physician places one hand on the knee joint to keep the lower limbs straight, while the other hand lifts the lower limbs. The normal person can elevate more than 70 degrees, if the elevation is less than 30 degrees, that is, there is a radioactive pain from top to bottom, for a positive straight leg elevation test, on this basis can be carried out straight leg elevation strengthening test, that is, the examiner will raise the patient’s lower limbs to the maximum, put down about 10 degrees, when the patient is not paying attention, suddenly dorsiflexion of the foot, if it can cause lower limb radiation pain is positive. It is used to identify pain caused by nerve root compression due to disc herniation and lesions caused by muscle and other factors. ②Healthy limb elevation test (also known as Fajcrsztajn sign, Bechterew sign, Radzikowski sign): when the healthy limb is elevated with straight leg, the nerve root sleeve on the healthy side can pull the dural sac to the distal side, thus causing the nerve root on the affected side to move downward as well. When the herniated disc on the affected side is in the axilla of the nerve root, the nerve root is restricted in its distal movement, causing pain. If the herniated disc is in the shoulder, the test is negative. When the patient is lying supine during the examination, sciatica on the affected side is positive when the straight leg on the healthy side is raised. (③) Supine jerk test: The patient takes a supine position and does a jerking up of the abdomen and lifting of the buttocks, so that the buttocks and back leave the bed. At this point, if the patient complains of radiating pain in the sciatic nerve of the affected limb, the test is positive. ④Femoral nerve pull test: The patient is placed in a prone position with the knee joint of the affected limb fully extended. The examiner elevates the straightened lower limb so that the hip joint is in the hyperextended position, and when the hyperextension reaches a certain level and pain occurs in the femoral nerve distribution area in front of the thigh, it is positive. This test is mainly used to examine patients with herniated discs in lumbar 2 to 3 and lumbar 3 to 4. However, in recent years, it has also been used to detect cases of lumbar 4 to 5 disc herniation, and its positive rate can be as high as 85% or more. ⑤ Head flexion neck test: the patient lies on his back, both lower limbs are straight and flat, slowly raise his head and flex his neck, at this time, there is radioactive pain in the lower limbs that is positive. (6) Sensory disorder: the nerve root innervation area is squeezed with sensory (including pain, touch and temperature sensation) disorder. The herniated disc mainly invades the lower two lumbar nerves and sacral 1 nerve roots, and determines the area of sensory alteration. The most common clinical herniated disc of lumbar 4/5 compresses the 5th lumbar nerve root, causing pain and numbness mainly on the lateral side of the calf, while the herniated disc of lumbar 5/sacral 1 compresses the 1st sacral nerve root, causing pain and numbness mainly on the posterior side of the calf. It is important to note that not all lumbar disc herniations are positive; for example, this test may be negative in patients with upper lumbar disc herniation. (7) Motor impairment: The function of the muscles innervated by the invaded nerve roots is often reduced. Lumbar 4 to 5 disc herniation compresses the lumbar 5 nerve root, resulting in reduced dorsiflexion of the innervated toes, accounting for 71.5% of cases. When the sacral 1 nerve root is damaged, the toe and foot plantarflexion force is reduced, and it is often impossible to stand on the ground with the toe of the affected side alone. (8) Reflex changes: knee reflex can be reduced in lumbar 3 and 4 disc herniation and unchanged in lumbar 4 and 5 disc herniation, but it can also be hyper or hypo. Achilles tendon reflex can be decreased or disappeared in up to 85% of cases of lumbar 5 sacral 1 herniation.