First, distinguish the types According to the theory of soft tissue surgery, most of the human pain diseases are caused by soft tissue damage inside and outside the lumbar spinal canal. These two types of damage can exist separately or mixed, and can be distinguished clinically based on the characteristics of the history, physical examination, imaging features and EMG performance. This is crucial for the choice of clinical treatment. (I) History characteristics 1. Resting pain versus motion pain. Lumbar extravertebral soft tissue damage due to myospasm, myoclonic degenerative adhesions of pathological changes, if the body is in a certain position for a long time, especially in the static state, it is bound to aggravate the ischemic damage, and ultimately lead to the exacerbation of aseptic inflammation of the soft tissues at the lesion. In this case, the body just need to carry out appropriate activities or walking, so that the blood supply of the lumbar soft tissues get improved, the pain can be gradually relieved. On the other hand, the inflammatory reaction of the fatty connective tissue outside the dural sac and nerve root sheaths in the lumbar spinal canal can only be controlled or subsided by adopting a braked recumbent position (no longitudinal pressure on the spine). Any activity in the upright position can only exacerbate the aseptic inflammation of the soft tissues outside the nerve sheaths, as the protruding mesenchymal discs or thickened ligamentum flavum are irritants to the dural sacs and nerve roots. The more the movement the more the pain will be exacerbated, sometimes manifested as a sudden pain after exercise, and only when lying down can relieve this pathological irritation. 2, the effect of increased abdominal pressure on pain. Intravertebral lesions due to increased cerebrospinal fluid pressure on the nerve roots or dura mater to produce direct pressure, when the nerve is in a state of irritation, naturally, due to forceful defecation, coughing, sneezing and so on to aggravate the pain. At this time, if you wear a waist cuff to reduce the axial pressure of the lumbar spine, it will offset part of the increased abdominal pressure, thus relieving the pain caused by this. Pain caused by soft tissue damage outside the spinal canal is rarely affected by changes in abdominal pressure. 3, the change of pain in a day. Morning lumbar and leg pain is obvious, even in the early hours of the morning because of the pain of waking up and can not lie down, have to get up and move to relieve the pain, daytime general work and activities are not impeded. This is the characteristics of the lumbar spinal canal outside the soft tissue damage pain. The lumbar spinal canal lesion patients in the morning in the day is the best time to feel the waist and legs, no pain or slight pain, such as the following bed activities in the afternoon or evening pain is the most obvious, sitting position also make the pain faster aggravation. 4, the nature of lower extremity pain. Lower extremity pain (sciatica in the broad sense) whether it is involving pain or radiating pain can be caused by the spinal canal of the spinal sinus nerve innervated by the dura mater, posterior longitudinal ligament, ligamentum flavum region of the irritation caused by the involving pain, nerve root involvement resulting in radiating pain, or outside the spinal canal, ligamentous damage due to the irritation caused by the nerve branches of the radiating pain and the area of its own damage caused by the involving pain. However, in the case of radiating pain to the lower extremities, the contraction of the vertebral canal force can cause extreme elevation of venous pressure in the vertebral venous plexus, which can then increase the pressure on the involved dura mater and nerve roots and aggravate low back pain and lower extremity pain. In a significant number of cases, the complaint is that the pain flares up due to back weight bearing and is not easily relieved on its own. Although the soft tissue outside the spinal canal damage is also difficult to hold weight, but the degree of impact is small, generally after rest and braking pain can disappear naturally. 6, the evolution of the disease process characteristics. Extra-vertebral tissue damage pain can be sudden onset, but generally in a short period of time can be relieved, and the intermittent period (relief symptoms) long, self-limiting obvious, do not need special treatment. Intravertebral lesions cause frequent sudden onset of low back pain, with intervals gradually becoming shorter as the number of episodes increases, and the episodes are long, usually requiring 2-6 weeks of specialized treatment before relief. The symptoms of low back and leg pain are recurrent if they are mild and severe. There is even no obvious cause, the frequency of attacks is getting higher and higher, and the interval period is shortened. Episodes from the beginning of self-relief to the inability to relieve, should be considered lumbar spinal canal inside and outside the mixed type of lesions caused by. It suggests that two different types of damage lead to the destabilization of the lumbar spine, which is also a manifestation of the severity of the disease. 7, Cauda equina damage is a characteristic of intravertebral canal lesions. Lumbar spinal stenosis, huge disc herniation or intravertebral canal tumor can lead to cauda equina compressive damage. The onset of ischemic limited arachnoiditis, functional damage, clinical manifestations of atypical lower limb paresthesia or swelling pain, almost all patients with intermittent claudication, once walking for too long or just walking on the ground that is, lower limb pain, the patient squatting to rest or lying down on their own pain is instantly relieved, so that the cycle of symptoms appear. When the cauda equina damage is severe, trigger foot occurs when taking steps or going up and down steps. Vesico-rectal dysfunction, from urinary weakness, constipation, and then develop into urinary and fecal incontinence, the patient perineum and perianal sensation decreased or disappeared. 8. Extreme conditions in the vertebral canal. If the lumbago or lumbar leg pain continues to develop and worsen progressively, and any non-surgical treatment is of no help, and there is weakness, heaviness or atrophy of the lower limbs, the existence of intravertebral canal tumors should be highly suspected and not allowed to be tolerated. If in the course of the disease, there is a sudden convulsion of the whole body or lower limbs, or even loss of consciousness, strong neck, severe pain in the low back, etc., then subarachnoid hemorrhage in lumbar vertebral canal should be considered, which is a kind of danger in lumbar and leg pain disease, and intradural extramedullary vascular tumors or variants should be further ruled out. 9.Involved low back pain. Primary abdominal or pelvic organ lesions, accompanied by lumbar back or lumbosacral one or several superficial pain, and at the same time there is segmental lumbar reflex muscle spasm, so the patient can also feel deep in the pain. Patients with so-called involved low back pain are often misdiagnosed and mistreated as primary low back pain and should be alerted. This patient’s damage is not in the pain site of the tissue, and not along the afferent fibers innervated by these tissues, but in some other innervations and lumbosacral tissues segmentally related to the visceral tissue, i.e., visceral injury sensation produces pain that can be perceived in the dermatomal region. In clinical evidence, gynecological disorders (e.g., dysmenorrhea, ovarian lesions, uterine prolapse, cervical cancer, etc.), upper urinary tract lesions (e.g., pyelonephritis, kidney stones, etc.), posterior appendicitis, and inflammatory disorders of the prostate gland can involve lower lumbar and dorsal pain or sacrococcygeal pain. (ii) Physiologic examination. The “three clinical tests of lumbar spine” proposed and recommended by Hikari Hsuan have distinct specificity for lesions within the lumbar spinal canal, and can accurately make differential diagnosis with lumbar spinal canal and extra-vertebral soft-tissue damages of low back pain. Lumbar disc herniation, lumbar spinal stenosis, inflammatory tissue reaction outside the nerve root and dural sac, and nerve tumors can all show common positive signs of the three tests. The test has both specificity and sensitivity in clinic, and the detection rate is quite high. 1. Clinical significance of thoracic and abdominal pillow test (1) Positive thoracic pillow test suggests lumbar spinal canal lesions. (2) Abdominal pillow test is positive, can be considered for the soft tissue damage outside the spinal canal lumbago. 2, lumbar scoliosis test clinical significance ① spinal curvature to the affected side triggered deep pain in the lumbosacral region, or concomitant buttocks and lower limbs radiating pain or numbness, it is a positive sign, can be judged to have intradural pathogenesis factors. (2) If the spinal curvature reaches an extreme degree to the healthy side, so that the deep lumbosacral pain and lower extremity signs induced by the original scoliosis test on the affected side disappear completely, it is also shown as a positive sign of this test. (2) If the spine is curved to the healthy side and there is pain in the lumbar region on the affected side, it can be judged as soft tissue damage outside the lumbar spinal canal. If pain in the lumbar or lumbosacral region is induced by bending the spine to the affected side or to the healthy side, it will be judged as lumbar pain caused by mixed lesions inside and outside the lumbar spinal canal. Clinical significance of tibial nerve flick test Anyone who flicks the tibial nerve trunk during examination and experiences localized pain or conductive soreness and numbness in the calf is positive for this test. If the finger presses the nerve trunk or the joint capsule at the back of the knee, false positive signs can be induced. (C) Imaging features 1. X-ray plain film. The following changes are used as reference. (1) Interdiscal changes. (2) Frontal and lateral intervertebral sequence/curve changes. Lumbar spinal canal lesions (lumbar disc herniation) can occur lumbar scoliosis and lumbar spinal kyphosis, in the case of severe damage to the soft tissues of the lumbar or buttock region can likewise occur, and clinically often manifests itself as a severe mixed lumbar intra- and extra-vertebral canal lesion. 2.CT scan or MRI examination. Measurement of the size of the spinal canal, i.e. the presence or absence of stenosis (central spinal canal, lateral spinal canal, intervertebral foramina) and structural and morphologic changes in the contents can be used as a hint. The shape, size, location, segmental range and relationship with the dural sac and nerve root of the herniated disc can be more clearly diagnosed. The detection rate of vertebral canal tumor is also very high, which has important reference value. Determine the site (a) lesions in lumbar spinal canal 1. Functional activities of lumbar spine in forward flexion and backward extension. The lumbar anterior flexion activity is firstly accomplished 50% by hip flexion, and secondly really accomplished 50% by the lumbar spine itself. About 75% of the lumbar anterior flexion activity is mainly dependent on the function between L.5-S.1 (the remaining 25% of the function is accomplished by L2-5). When there is a herniated disc at L.5-S.1 or damage to the lumbosacral or sacrospinal muscles it will significantly limit forward flexion activities. In contrast, lumbar posterior extension activities are mainly accomplished by lumbar vertebrae 2-5 segments for posterior extension activities. The above conditions make the L.5-S.1 segments less affected, thus limitation of lumbar posterior extension activities with neurological symptoms should be considered for L.3-4/L.4-5 segment lesions. Similarly, the motion segment that affects sitting work should be the L.5-S.1 segment. 2, lumbar spine paraspinous or median area of pressure pain, can suggest that the spinal canal segmental damage. The interspinous pressure pain with interlaminar pressure and radiating pain in the lower limbs beside the spinous process indicates a centralized lateral herniation of the intervertebral disc; if there is only interspinous pressure pain or interlaminar pressure beside the spinous process and radiating pain in the lower limbs, then it should be considered as a centralized or lateral type of herniation of the intervertebral disc. Of course, the location of the pressure pain is of great value in distinguishing the damage of different segments of the spine, especially the spinous process percussion pain is very meaningful in the detection of intravertebral space-occupying lesions, which can be used as a screening method before CT scan/MRI examination. 3.Neurologic localization signs. It has high diagnostic value, but the clinical manifestation is late. (1) Sensory loss or disappearance. The distribution of sensory nerves in the lumbar back is mainly innervated by the posterior branch of the spinal nerve; the distribution of sensory fibers in the vertebral canal is innervated by the vertebral sinus nerve issued by its posterior branch, and the limbs are innervated by the sensory branches issued by the plexus composed of the anterior branch of the spinal nerve. Therefore, the sensory impairment in the dermatomal area corresponding to the innervation of the affected nerve root can be used as a reference for the diagnosis and localization of lumbar spinal canal lesions. However, the premise is to first distinguish the two kinds of lesions inside and outside the spinal canal. When the sciatic nerve trunk and its branches are compressed by spasm or degenerative contracture of the soft tissues in the lumbar and buttock regions, the sensory loss or loss of sensation in the dermatomal area innervated by the lumbar nerve root will be the same as that of the lumbar nerve root itself. Sciatica and hyperalgesia or hyperalgesia of the lateral calf are common signs of both internal and external damage to the spinal canal. (1) Lateral thigh dermatomal area. It comes from the nerve branches of the lumbar plexus (L.2, 3). ② Anteromedial cortical area of the anterior calf. Nerve branches from the lumbar plexus (L.4). (iii) Posterolateral thigh, lateral calf cortical area, lateral ankle, dorsum and medial three toe cortical areas. From the sacral plexus (L.5-S.1) nerve branches. ④ The posterior thigh, posterior calf, plantar or lateral margin of the foot and the lateral two pedicled dermatomes. From the sacral plexus (L.5-S.1, 2) nerve branches. (2) Muscle weakness. Muscle weakness in different parts of the body reflects the affected ganglion. For example, quadriceps muscle weakness reflects L.2, 3, 4 segmental involvement (knee extension ↓); tibialis anterior muscle muscle weakness reflects L.4 segmental involvement (dorsiflexion ↓); extensor hallucis longus muscle weakness reflects L.5 segmental involvement (bunion extension ↓); plantarflexion and flexor digitorum profundus muscle weakness reflects S.1 segmental involvement (plantar flexion of the toes ↓); but it must be noted that the muscle weakness or atrophy is also a common sign of intra- and extravertebral canal pathology. Clinically, a single-footed body support maneuver (kamikaze stance) can indicate S.1 ganglion involvement or not. (3) Reflex deficits. The tendon reflexes of the lower limbs have a more accurate localization significance. In intravertebral lesions, it is possible to identify the affected ganglion. Decreased or absent knee tendon reflexes reflect lesions in L.3 and 4 segments. Decreased or absent Achilles tendon reflexes reflect lesions in the S.1 segment. If there are pathological reflexes such as Babinski’s sign, we should consider the intravertebral canal lesion to the vertebral body bundle sign in the cervicothoracic spine, which is mostly caused by the spinal cord damaging lesion. 4. Prone position knee flexion and hip extension test: This test can be positive if the L.4-5 disc herniation stimulates and compresses the L.5 nerve root. However, if the L.5-S.1 disc herniation stimulates and compresses the S.1 nerve root, this test will not induce radiating pain in the lower limbs, so it can distinguish nerve damage in the L.4-5 segment from that in the L.5-S1 segment. (II) Soft tissue damage outside the lumbar spinal canal 1. Pressure points and referred pain (1) Pressure points in the lumbar gluteal region. Pressure point of superior gluteal cutaneous nerve; pressure point at the inferior outlet of sciatic nerve pyriformis muscle; pressure point at the superior outlet of superior gluteal nerve pyriformis muscle; pressure point at the inferior outlet of inferior gluteal nerve pyriformis muscle; pressure point at the slapping fossa of tibial nerve; pressure point at the inferior inferior inferior inferior inferior inferior inferior inferior inferior inferior inferior adipose cushion; pressure point below the medial ankle (posterior tibialis tendon and tendon sheath); pressure point below the lateral ankle (peroneus longus and shortus tendon and tendon sheath). (2) Drawing pain. Soft-tissue damage to the area innervated by the spinal sinus nerve or posterior spinal nerve branches may produce radiating pain in the lower extremities similar to spinal nerve root involvement. Usually the path of the radicular pain is vague and not always distant, and in a few cases it may reach the end of the limb. 2. Functional examination. It can confirm the pressure point and help to localize the pain. (1) Straight leg raising test: sciatic nerve tension; (2) Flexed knee and hip split leg test: adductor group; (3) Hip abduction test: gluteus medius; (4) Iliotibial bundle tension test; (5) Hip internal rotation test: pyriformis muscle; (6) Sacroiliac joint test: “4” test, gonadalgia test, Avery’s test; (7) Bin fat pad squeeze sign; (8) Mai’s test: meniscus; (9) Drawer test: cruciate ligament of the knee; (10) Femoral nerve tension test. Third, distinguish the nature. The nature of the lesion can be clarified based on clinical features, imaging and laboratory diagnosis. (I) Intravertebral canal diseases 1. Tumor or specific lesion (1) Tumor: neurofibroma, nerve sheath tumor, nerve root cyst, dermoid cyst, ventricular meningioma, metastatic carcinoma (liver, kidney, prostate, ovary), glioblastoma of the spinal cord, neuroblastoma, and actinic neoplasm. (2) Malformations (sacralization, lumbarization, spina bifida). (3) Spinal cord cavernous disease, multiple sclerosis. 2. Common disorders. (1) Lumbar disc herniation (central, lateral paracentral, lateral, extreme lateral, anterior). (2) Thoracolumbar spinal stenosis (congenital, developmental, degenerative, traumatic, medical, mixed). (3) Lumbar spondylolisthesis (leading to secondary spinal stenosis). (4) Soft tissue damage (hypertrophy of ligamentum flavum, calcification of posterior longitudinal ligament, degenerative contracture of fatty connective tissue, etc.). (ii) Extra-vertebral canal lesions. 1. Tumor or specific lesion (1) Spinal tumor, tuberculosis, eosinophilic granuloma. (2) Sequelae of spinal injury: compression fracture, split fracture, fracture dislocation. (2) Rheumatoid arthropathy. Rheumatoid arthritis, ankylosing spondylitis, osteoarthritis, Lister’s syndrome, systemic lupus erythematosus, gouty arthritis, dermatomyositis and reactive arthritis, sacroiliac joint disorders, ischemic necrosis of the femoral head. 3. Organ diseases and systemic diseases. Hepatobiliary and digestive system, genitourinary disorders, gynecological disorders, endocrine disorders (hypothyroidism, diabetes, aldosteronism). 4. Vascular diseases. Thromboembolic vasculitis, thrombophlebitis, thrombosis of the common iliac artery or external iliac artery. 5, Soft tissue damage (including myofascial pain syndrome, fibromyalgia syndrome). Roughly divided into the lumbar muscle group, gluteal muscle group, internal retractor femoris muscle group, lateral abdominal muscle group, slap cord muscle group, medial and lateral head of gastrocnemius muscle, inferior pinna fat pad, peroneus longus shortus, posterior tibialis muscle group, soft tissues of tarsal sinus, and metatarsal tendon membrane, etc. Injurious aseptic inflammatory reaction. 6. Infectious. Herpes zoster, lymphangitis.