1, resting pain and dynamic pain The soft tissue damage outside the lumbar spinal canal is due to pathological changes of muscle spasm and muscle contracture degenerative adhesions. If the body is in a certain position for a long time, especially the resting state, it is bound to aggravate the ischemic damage, which eventually leads to the aggravation of aseptic inflammation of the soft tissue at the lesion. The pain can be gradually relieved if the blood supply to the soft tissues of the lumbar region is improved by appropriate activity or walking. The inflammatory response in the lumbar spinal canal in the epidural sac and in the extra-sphincteric fatty connective tissue of the nerve roots can only be reduced by adopting a braked recumbent position (no longitudinal pressure in the spine). Any activity in the upright position only exacerbates the aseptic inflammation of the soft tissue outside the nerve sheath, as the protruding disc or thickened ligamentum flavum are irritants to the dural sac and nerve roots. The more you move, the more it will intensify the pain, sometimes manifesting as sudden onset of pain after movement and pain relief only when lying still. 2, the effect of increased abdominal pressure on pain Intraspinal lesions due to increased cerebrospinal fluid pressure and direct pressure on the nerve roots or dura, when the nerve is in an agitated state, such as forceful defecation, coughing, sneezing, etc. aggravate the pain. Wearing a waist brace to reduce the axial pressure on the lumbar spine will offset some of the increased abdominal pressure, thus relieving the resulting pain. The pain caused by soft tissue damage outside the spinal canal is less affected by changes in abdominal pressure. 3, daytime pain changes lumbar spinal canal soft tissue damage pain: morning back and leg pain is obvious, and even waking up in the early morning hours because of pain and can not lie down, must get up and move to relieve the pain, daytime work and activities are generally not hindered. Lumbar spinal canal lesion pain: no pain or slight pain in the morning, the most obvious pain after getting out of bed or in the afternoon or evening, sitting position also makes the pain more quickly. 4, the nature of lower extremity pain is different sciatica (referred pain or radiating pain) all originate from the dura mater, posterior longitudinal ligament, yellow ligament area innervated by the sinus nerve in the spinal canal caused by stimulation of referred pain, nerve root involvement resulting in radiating pain, or the stimulation of nerve trunk branches due to muscle and ligament damage outside the spinal canal causes radiating pain and its own damage area causes referred pain. Intraspinal lesions appear mostly or only in single segments, often involving the distal nerve sensory distribution areas of the lower extremities, with a high chance of coexisting pain and numbness. Extradural soft tissue damage presents with radiating lower extremity pain, but sensory deficits in the distal lower extremity (foot) are less common. Clinically, there is an extremely high chance of involvement pain appearing, while the site of lower extremity pain is more vague and conduction to the foot is uncommon, usually the lumbar or hip area is dissipated to the posterior lateral side of the lower extremity to the s fossa. 5. The effect of lifting heavy objects When the abdominal pressure rises, especially when holding weight at the waist, the strong contraction of the thoracic and abdominal muscles can cause the venous pressure in the vertebral plexus to rise extremely, which can increase the pressure of the affected dura mater and nerve roots and aggravate the low back pain and lower limb pain. In a significant number of cases, the pain flares up due to lumbar weight-bearing in the complaint and does not easily resolve on its own. Although the soft tissue damage outside the spinal canal is also difficult to hold the weight, but the degree of impact is smaller, and the pain can generally disappear naturally after rest and braking. 6, the evolution of the disease process characteristics of extradural tissue damage pain can be sudden onset, but generally in a short period of time can be relieved, and the interval (relief symptoms) is long, self-limiting obvious, generally do not need special treatment. Intravertebral lesions cause sudden and frequent episodes of low back pain, and the interval gradually becomes shorter as the number of episodes increases, and the episodes are long and usually require 2-6 weeks of specialized treatment to be relieved. If the symptoms of low back pain are mild and severe, and recurrent. There is no obvious cause, and the frequency of attacks becomes higher and the interval is shorter. If the episodes change from self-relieving at the beginning to unrelieving, a mixed lesion inside and outside the lumbar spinal canal should be considered. It is suggested that two different types of damage lead to destabilization of the lumbar spine and is also an indication of the severity of the condition. 7, cauda equina damage is a characteristic of intra-vertebral canal lesions, lumbar spinal stenosis, huge disc herniation or intra-vertebral canal tumors can lead to cauda equina compression damage. The onset of the disease starts as ischemic limited arachnoiditis, functional damage, clinical manifestations are atypical numbness and tingling sensation or sunken pain in the lower extremities, intermittent claudication in almost all patients, and such symptoms appear in cycles. In severe cauda equina damage, wrenching of the foot when taking steps or going up and down stairs occurs. Cystorectal dysfunction, from weakness in urination and constipation, progresses to urinary and fecal incontinence, and the patient has decreased or absent sensation in the perineum and perianal area.