11.What are the special examination methods for lumbar disc herniation? The special examination methods for lumbar disc herniation are: (1) Straight leg raise test positive. The specific method is as follows: the patient lies supine with both lower limbs straight, the examiner holds the patient’s knee with one hand to straighten the knee joint, holds the ankle with the other hand and raises it slowly until the patient has radiating pain in the lower limbs, and records the angle between the lower limbs and the bed at this time, which is the angle of straight leg elevation. The angle between the lower limb and the bed at this time is recorded as the straight leg elevation angle. Normal people can generally reach about 80 degrees without radiating pain. On this basis, the straight leg elevation test can be performed, i.e. the examiner elevates the patient’s lower limb to the maximum, then puts it down about 10 degrees and suddenly dorsiflexes the foot when the patient is not paying attention, which is positive if it can cause radiating pain in the lower limb. The principle of this test is that when the lower limb is elevated, the sciatic nerve is stretched, which increases the stimulation of the nerve root by the herniated lumbar disc. In the straight leg elevation test, lower limb elevation at 0-20 degrees does not cause movement of the nerve root in the spinal canal, so the restriction in this range is mostly due to N cord muscle spasm. After the lower extremity elevation exceeds 30 degrees, it can cause the nerve roots to pull or move downward, where the largest pull is on the lumbar 5 nerve root, followed by the lumbar 4 nerve root. When the elevation angle exceeds 60 degrees, the lumbar 5 nerve root is subjected to maximum tension and is sufficient to move downward in the spinal canal. Because of the greater pulling force on the lumbar 5 and lumbar 4 nerve roots, the straight leg elevation test is mostly positive in patients with lumbar 5 to sacral 1 and lumbar 4 to 5 disc herniation. In patients with more severe lumbar disc herniation, not only the straight leg elevation test on the affected side is positive, but also the straight leg elevation test on the healthy side can be positive because the nerve roots can pull the dural sac when the lower limb on the healthy side is elevated, thus correspondingly changing the relative position of the nerve roots on the opposite side and the herniation, and inducing pain. The straight leg raise strengthening test can be used to differentiate between neurogenic or muscle-induced restrictions in straight leg raise. The straight leg raise test is usually negative when the restriction is due to tension in the iliotibial bundle, N cord muscle, or posterior knee capsule. A positive straight leg raise test bilaterally suggests the possibility of a central protrusion; most patients have a positive straight leg raise strengthening test. Several issues should be noted: ① The healthy side should be examined first, and the healthy side should be used as the standard for comparison; pain at an elevation angle lower than that of the healthy side is positive. The normal range of lower limb elevation is 60 to 120 degrees, and some athletes and women can have straight leg elevation greater than 90 degrees even if they have lumbar disc herniation, and these people should be standardized by the presence or absence of pain. ②Lumbosacral lesions and sacroiliac joint lesions, this test can also be positive. (2) Positive supine jerk test (also known as jerk and breath-hold test). The patient can be put in the supine position, both hands are placed on the side of the body, and the abdomen is lifted upward with the occiput and both heels as the pressure points, and if lumbar pain and radiating pain of the affected lower limbs can be felt, it is positive. If the pain cannot be elicited, deep inspiration can be taken and held for 30 seconds while maintaining the above position until the face is flushed and the affected limb radiates pain, or coughing hard while lifting the abdomen and the affected limb radiates pain is also considered positive. If the above methods do not trigger the pain in the affected limb, you can also use both hands to compress the jugular vein when the patient is holding the abdomen, and if there is pain in the affected limb, it is still a positive sign. The principle of this test is to increase the pressure in the spinal canal by increasing the intra-abdominal pressure to stimulate the lesioned nerve roots, triggering low back pain and pain in the affected lower limb. (3) Flexion neck test (Linder’s sign). Let the patient lie down with the limbs naturally flattened, the examiner rests one hand on the patient’s occiput and presses the other hand on the patient’s chest. The patient’s neck is slowly flexed, and the test is positive if it triggers lumbar pain and radiating pain in the lower extremities. The principle of this test is: flexing the neck to make the occiput leave the bed, which can make the spinal cord rise about 2cm, and make the dura and nerve roots stretched, increasing the tension of the nerve roots that have already been lesioned. (4) The bowstring test can be positive. The patient is placed in the supine position, and the affected hip and knee are flexed to 90 degrees, and then the knee is gradually straightened until sciatica occurs. At this point, the sciatica is significantly reduced or disappears when the knee joint is slightly flexed. This test can be used to differentiate between low back pain caused by lumbar disc herniation and low back pain caused by muscular factors. It is also known as the prone bowstring test. (5) Positive straight leg elevation test on the healthy side. When the healthy limb is passively elevated with the straight leg, pain in the sciatic nerve distribution area of the affected limb is positive. It may be a central herniation or when the herniated disc is in the axilla of the nerve root. Positive femoral nerve pull test (Ely) test, mostly seen when a high lumbar disc is herniated. It is also positive when there are lesions in the psoas major muscle, sacroiliac joint and lumbar spine. The procedure is: the patient lies prone, the examiner presses the pelvis with one hand and lifts one lower limb with the other hand to flex the knee joint and hyperextend the hip joint, if the groin or the front of the thigh and the inner front of the calf radiates pain, it is positive. (7) Nafziger’s sign is also known as jugular vein compression test. Its operation is: the patient takes a standing or sitting or lying position, and the examiner compresses the jugular veins on both sides of the patient with his hands, or wraps the rubber capsule of the sphygmomanometer around the neck and pressurizes it to 5.3-8.0 Pa (40-60 mmHg), which raises its intracranial pressure and further causes the cerebrospinal fluid pressure to increase and the dural sac to dilate, thus pushing the nerve roots to the lateral side and increasing its pressure, causing symptoms such as pain and numbness in the affected limb. Such symptoms can develop from top to bottom or from bottom to top. The highest positive rate is detected in the standing position, and it is especially suitable for the examination of lumbar 4 to lumbar 5 disc herniation. 12, what is the significance of electromyography for lumbar disc herniation? There are two types of conductive electrodes: surface electrodes and needle electrodes. The surface electrode can derive the synthetic potential of the entire muscle activity at depth, but cannot distinguish the potential of a single muscle. The needle electrode can be inserted into the muscle to be examined to derive the action potential of individual muscles, so this method is more commonly used. When examining a patient with lumbar disc herniation, the anterior tibialis, peroneus longus, gastrocnemius, extensor digitorum longus, and sometimes the quadriceps are examined bilaterally. If the lumbar 4 to lumbar 5 discs are herniated, the lumbar 5 nerve roots are mostly affected, and the innervated tibialis anterior, extensor digitorum longus and peroneus longus muscles often show abnormal potentials when electromyography is performed. For example, when the lumbar 5 and sacral 1 discs are herniated, they mostly affect the sacral 1 nerve root, which is reflected in the abnormal potential of the gastrocnemius muscle on electromyography, while the quadriceps and tibialis anterior muscles have no abnormal potential. The presence of abnormal potentials in the quadriceps indicates lumbar 4 nerve root involvement and often indicates the possibility of lumbar 3 to lumbar 4 disc herniation. It is worth noting that the presence of abnormal muscle potentials indicates nerve root compression, and if the compression factors are not released in time, nerve root changes may occur. 13.What is the significance of ultrasonic diagnosis for patients with lumbar disc herniation? Since the 1990s, the value of ultrasound as a non-invasive examination means in disc herniation has been increasingly valued by scholars at home and abroad. Ultrasound can be used to determine the canal diameter of the lumbar spinal canal, and the size of the canal is implicated in the production of radicular symptoms. MRI and CT are currently the best methods to determine the volume of the spinal canal. Myelography does not perform well for trilobar spinal canal, which has a significantly smaller cross-sectional area. Ultrasound diagnosis is measured by placing the probe 1 cm next to the midline of the lumbar spine. The ultrasound probe is placed at a 15 degree angle of intersection. In the same inclined plane from lumbar 1 to lumbar 5 for longitudinal movement. To obtain the echoes reflected back from the back of the vertebral plate, the front and the back of the vertebral body. The interval time of different echoes was related to the distance of the reflex plane. The measurement results show that in most patients with lumbar disc herniation, the oblique sagittal diameter value of the spinal canal is smaller than that of asymptomatic patients, and the narrowest canal diameter is in lumbar 5. When the canal diameter of lumbar 5 is less than 1.4 cm, the failure of simple lumbar disc removal may be large, and the reason is related to spinal stenosis. Thus, the ultrasound diagnosis of lumbar disc herniation is not a direct diagnosis, but it has certain guiding significance for its treatment plan, especially the selection of surgical methods. 14.What is the significance of two-dimensional color Doppler imaging for patients with lumbar disc herniation? The sonogram of a normal lumbar disc shows the vertebral bodies and intervertebral spaces along the median longitudinal section of the abdomen. The vertebral body is staged with neat, extraordinarily strong echogenicity, with an extraordinarily strong arc-like band of light in front and a wide, loud posterior shadow, with the posterior portion of the vertebrae and subsequent tissues poorly visualized, and the gap between the vertebral body and the vertebral body is an intervertebral disc echo. In transverse section along the mid-abdomen, the vertebral body cross-section shows only a superficial arc-like strong echogenic band with posterior acoustic attenuation and poorly visualized structures. In the intervertebral space transverse section of the disc, the anterior edge of the disc is the interface between the anterior longitudinal ligament and the anterior edge of the disc, with clear and regular margins, and the posterior part of the disc is more uniformly hypoechoic in a circular or oval shape, and the central part of the disc is the nucleus pulposus, and the surrounding nucleus pulposus is uniformly slightly hypoechoic in the middle dimensional ring of the disc. The posterior part of the intervertebral disc is the spinal canal, the edge of which is rounded with strong echogenic photophores consisting of the anterior wall of the dural sac, the posterior longitudinal ligament, the posterior wall of the dural sac, and the ligamentum flavum. The halo is round or oval in shape, with smooth and neat edges and no restrictive pressure marks or protrusions. Within the halo is the spinal cord, which is echogenic, with occasional small dot reflections. The normal height of the same intervertebral space (i.e., the thickness of the lumbar disc) differs significantly in the prone and standing positions. It is slightly thicker in the recumbent position, about 14 mm on average; in the sitting and standing positions, the thickness of the intervertebral space becomes thinner, about 11 mm; in the standing position, the intervertebral space distance is reduced by about 2-4 mm on average. The thickness of the lumbar intervertebral disc varies slightly from site to site. The sonogram of lumbar disc herniation mainly shows bulging and protrusion. The bulge can be seen as annular bulge and limited bulge, which can be bulged to the middle or to both sides, more to the left than to the right, the scope of bulge can be large or small, and the envelope is smooth and intact. The annular bulge often does not compress the nerve and does not cause symptoms. Lumbar disc herniation can be manifested as protrusion and prolapse, limited displacement is more obvious, the range of movement is greater, the hypoechoic nucleus pulposus is encircled by a thin slightly hypoechoic fibrous ring, the boundaries are still clear, compression of the surrounding tissue, long-term recurring attacks can make the nucleus pulposus fibrosis and mechanization. Subsequently, the spinal cord is compressed, the circular arc of the strongly echogenic halo disappears, and its anterior and posterior diameters are significantly reduced, usually less than 8 mm (normal value is greater than 13 mm), and in severe cases the compression is crescent-shaped, with asymmetry on the left and right sides of the transverse section of the spinal canal, with uneven margins and limited compression. The intervertebral space distance becomes smaller and the changes are not obvious in sitting and lying position, indicating degeneration of the disc and reduced elasticity of the disc. In detecting patients with lumbar disc herniation, it is difficult to understand the blood supply to the herniated disc because the vascular alignment around the disc is mostly perpendicular to the acoustic beam, plus the disc is far away from the probe. However, the better performing ultrasound has a broadband probe and a variable frequency probe, which can display the disc condition and make the images clearer and better avoid the occurrence of false positives and false negatives. With the improved performance of the instruments, an in-depth study of the blood supply in lumbar disc herniation has become possible. The disadvantage of color ultrasound is that it is easily affected by gas and bone, but ultrasound sections can be obtained arbitrarily, the body position can be changed at any time, and the thickness of the disc can be measured in the prone and standing positions to infer the elastic function of the disc. The effect of real time observation is also available, and there are many methods to examine lumbar disc herniation. The sensitivity of ultrasound is 89%, and the specificity is 100%. Examination position: generally supine position, or prone position for those who cannot lie down due to severe pain. Preparation before examination: fasting for 8-12 hours, emptying the bowel and urine, and routine preparation of the intestine when there is gas accumulation in the intestine to prevent interference of ultrasound by intestinal gas and contents, which may affect the imaging effect. Scanning method: first longitudinal scanning, to understand the situation around the vertebral body and vertebral body, pay special attention to the situation between the vertebral body, and measure the distance between the vertebrae in the lying position. Then cross-sectional scan, carefully observe the intervertebral space plane, when scanning the upper lumbar intervertebral space plane, the probe and the body long axis perpendicular. When scanning the lower intervertebral space, the probe is slightly tilted distally to the cephalad side so that the ultrasound section and the intervertebral space are parallel, and this technique is determined by the physiological curvature of the lumbar spine. A top-down, or bottom-up, transverse section is performed in each vertebral space, and when the transverse section is performed, a small-angle fan-shaped transverse scan is made in the intervertebral space to obtain a real-time dynamic image of the intervertebral disc. The patient is then made to sit or stand and the upper and lower diameters of the vertebral space under loading conditions are measured. Finally, the blood supply to the intervertebral disc and surrounding area is observed. Depending on the severity of the condition and symptoms, it can be reviewed once every 2 to 3 months, or once every 2 weeks for special cases or serious conditions. To understand the recovery of the herniated disc. The method of judging the site of lumbar disc herniation: and the vertebral space at the level of the umbilicus is the L3 to 4 vertebral space, and the line of the flat anterior superior iliac crest is the L4 to 5 vertebral space, in order to judge and locate. 15.What is the significance of isotope examination for lumbar disc herniation? It is confirmed by practice that isotope bone scan cannot be used to diagnose lumbar disc herniation. However, it has a good differential diagnosis for some other diseases with similar symptoms to lumbar disc herniation, such as intervertebral discitis, ankylosing spondylitis and secondary bone tumors. For patients who cannot be examined by imaging, a medullary scan can also provide the site of stenosis and obstruction, but its effect is not as accurate as the positioning of imaging. 16.Is lumbar far-infrared thermography helpful in diagnosing lumbar disc herniation? The answer is yes. The main imaging principle of medical far-infrared thermogram is to receive infrared radiation emitted from the human body, which can accurately determine the temperature of the body surface and express the temperature of each point in the form of a two-dimensional temperature field, i.e. thermogram. Its temperature resolution reaches 0.05℃, and the spatial resolution of the image is more than 1.5 milli-radians, which can sensitively reflect the change of the body surface temperature and its distribution characteristics. If the body surface temperature changes due to internal pathology, the far-infrared thermogram can reflect it through the thermogram. In lumbar disc herniation, the temperature of the body surface can be changed, and the far-infrared thermography can reflect this temperature change. The characteristics of the far-infrared thermogram of the waist and lower extremities of normal people: the waist is mostly a uniform cold area, especially for those with a fat body shape, and there can be a light red hot area at the location of the lumbar and sacral vertebrae, but the temperature does not exceed 34℃, and the range of the hot area conforms to the normal anatomical structure of the lumbosacral vertebrae, without the phenomenon of expanding the range of the hot area. The characteristics of far-infrared thermogram of lumbar disc herniation are as follows: abnormal thermal zone appears in the lumbosacral region, rhombic or pike shaped, which can be shown as a piece of uniform red, mostly prominent in L4~5 and L5~S1, and the range of thermal zone expands, and sometimes a dark red thermal zone can appear within the red thermal zone, and it is mostly biased to the affected side. The cause is considered to be the aseptic inflammation of the nerve root and its surrounding tissues caused by the herniated disc, local inflammatory material infiltration, microvascular dilation, increased blood flow rate, and increased local temperature, causing an increase in the temperature of the skin area of the corresponding segment. In addition, local inflammatory material stimulation and pain caused by nerve root compression can cause local muscle tension and spasm, and enhanced metabolism, which can also increase the body surface temperature. The far-infrared thermographic manifestation of lumbar disc herniation corresponds to the anatomical features of lumbar disc herniation. The more extensive the thermal zone and the higher the local temperature, the more severe the inflammatory changes caused by the herniated disc and the more severe the impact on the nerve roots. The far-infrared thermogram of the affected limb mostly shows a low temperature zone, sometimes lower than that of the healthy side, which is considered to be caused by the compression of the nerve root on the affected side, affecting the contraction function of the blood vessels supplying the corresponding limb and resulting in reduced blood perfusion in the limb. However, some patients have increased skin temperature in the posterior femur of both lower extremities, which may be due to painful stimulation causing local skin vasodilation and enhanced metabolism. The analysis of far-infrared thermogram of the lower extremities should be based on the specific situation of the patient, and other factors affecting the skin temperature change should be considered, such as arthritis, degenerative joint degeneration, etc. Far-infrared thermography has the characteristics of early diagnosis, non-invasive and convenient, and can visually reflect the distribution of the abnormal thermal zone of lumbar disc herniation and quantitatively detect the temperature change of the abnormal thermal zone. The specific operation is to conduct the examination after 15min quiet rest, the temperature in the examination room is 24～26℃, the examination distance is 4～5m, the examinee exposes the lumbosacral and both lower limbs, adjusts the focal length and the probe direction, scans the lumbar back and both lower limbs, the far infrared thermogram indicates the skin temperature of each part by displaying different colors, adjusts the temperature window to the appropriate color contrast and then saves. The corresponding colors from high temperature to low temperature on the thermal image were dark red, red, light red, yellow, green, light blue, dark blue and black in order. Analyze the range of thermal zones in the lumbosacral region and both lower extremities, measure the temperature of the center of the abnormal thermal zone and its difference with the peripheral temperature. 17.What is the role of peripheral nerve evoked potential and segmental somatosensory evoked potential examination for patients with low back pain? Peripheral nerve evoked potentials and segmental somatosensory evoked potentials are both types of somatosensory evoked potentials. It is a method to determine nerve damage and repair by recording the bioelectrical activity of the central nervous system after stimulation. Peripheral nerve evoked potential examination can be achieved by measuring motor nerve conduction time and velocity and sensory nerve action potential and conduction velocity. The purpose is to understand the degree of peripheral nerve damage, and for spinal nerve root compression caused by, for example, lumbar disc herniation or lumbar spinal stenosis, periodic examinations can be used to analyze the results to determine whether the damaged nerve shows signs of recovery. This is a means of observing the effects of conservative treatment for patients suffering from lumbar disc herniation who do not wish to undergo surgery. It is also a more valuable indicator for patients who have a long history of milder but recurrent disease. Segmental somatosensory evoked potentials are evoked by stimulating the cutaneous sensory distribution area innervated by a certain sensory nerve fiber, which is valuable for localizing and diagnosing nerve injury. For patients with lumbar pain, stimulation of the skin innervation areas specific to lumbar 4, lumbar 5 and sacral 1 nerve roots can be used to assist clinical diagnosis. 18.What pathology is reflected in the lumbar orthopantomogram of patients with lumbar disc herniation? In a normal orthopantomograph of the lumbar spine, the vertebral body is neatly arranged without scoliosis, the spinous process is basically in a straight line, the vertebral bone is intact and undamaged, the vertebral space is equal in width, the articular synapses are neatly arranged, and the joint space is clear. There were no pathological changes such as migrating vertebrae and spina bifida. The lumbar muscles on both sides of the lumbar vertebrae showed a triangular shadow from the internal superior oblique to the external inferior oblique line, and both sides were symmetrical. The iliac wings on both sides were equal and the pelvis was symmetrical. In the lumbar orthopantomogram of a patient with lumbar disc herniation, the following signs may be seen: (1) Lumbar scoliosis: Scoliosis is mostly seen in lumbar 4 and lumbar 5 disc herniation, and the direction of scoliosis can be convex either to the affected side or to the healthy side. It is generally believed that scoliosis is a compensatory change caused by compression of the nerve root by the herniated material. When the herniated nucleus pulposus is located on the medial side of the nerve root, the lumbar scoliosis is convex to the healthy side; when the herniated nucleus pulposus is located on the lateral side of the nerve root, the lumbar scoliosis is convex to the affected side. In the case of lumbar 5 and sacral 1 disc herniation, the lateral curvature is often not obvious. (2) Unequal widening of the intervertebral space from left to right: the intervertebral space on the convex side of the scoliosis is widened. This is also a compensatory response and not due to herniation occupancy. This sign has no special significance for the diagnosis of lumbar disc herniation. (3) Pelvic tilt: This is a protective posture commonly seen in patients with acute lumbar disc herniation. Different patients may have different x-ray manifestations depending on many factors such as age, disease duration or congenital factors, among which the distortion of the spinous process, especially the spinous process of the 5th lumbar vertebra, is often a result of development. It has no special clinical significance for the diagnosis of lumbar disc herniation. In addition, some congenital developmental malformations of the lumbar spine, such as lumbar sacralization, sacral lumbarization, occult spina bifida, and lumbar 3 transverse process hypertrophy, will be more clearly reflected on the X-ray orthopantomograph. 19.What are the pathological manifestations of lumbar lateral radiographs of patients with lumbar disc herniation? Lateral radiographs of the lumbar spine are more important than orthogonal radiographs for the diagnosis of lumbar disc herniation. On a normal lateral radiograph, a forward physiological projection of the lumbar spine and a posterior physiological projection of the sacral spine can be seen. A continuous line is made from the posterior lower edge of the thoracic 12 vertebrae to the posterior upper edge of the sacral 1 vertebrae, and an arc-shaped line is made along the posterior edge of each lumbar vertebra, both of which form an arch. The intervertebral space is wide at the front and narrow at the back, and is wedge-shaped. The width of the intervertebral space, except for the lumbar 5 and sacral 1 intervertebral spaces, is wider in the next intervertebral space than in the previous one. That is, the lumbar 4 to lumbar 5 vertebral space is wider than the lumbar 3 to lumbar 4 vertebral space, and the lumbar 3 to lumbar 4 vertebral space is wider than the lumbar 2 to lumbar 3 vertebral space. The intervertebral foramen becomes progressively narrower from top to bottom, and the lumbar 5 intervertebral foramen is often ear-shaped. The tip of the superior articular process of the inferior vertebral body is located below the level of the inferior edge of the superior vertebral body. The following signs are often seen in lateral radiographs of patients with lumbar disc herniation: (1) Change in the physiological anterior lumbar convexity: the physiological curvature of the lumbar spine may disappear, and in severe cases, a retroversion opposite to the normal anterior convexity may occur. This is a protective response to reduce compression of the nerve roots and dura mater. (2) Changes in the lumbar intervertebral space: In the lateral radiographs of patients with lumbar disc herniation, it can be shown that the next space is narrower than the previous space except for the lumbar 5 and sacral 1 intervertebral spaces. In the initial stage, the intervertebral space appears to be narrower anteriorly and wider posteriorly, and in the middle and late stages, the intervertebral space becomes significantly narrower, which implies rupture of the fibrous ring and prolapse of the pulp nucleus. (3) Osteomalacia at the anterior edge of the two vertebrae above and below the herniated part: due to the degeneration of the intervertebral disc, the adjacent vertebral body has abnormal movement, so that a bony flab is produced, which is also one of the pathological changes of the herniated disc. (4) Smaller intervertebral foramen: This is caused by the upward staggering of the supra-articular processes of the inferior vertebral body after the disc herniation. If the superior articular eminence enters the inferior arch notch, it may embed the nerve root that travels in it. (5) Calcified hyperplasia at the adjacent posterior margin of the lumbar spine: This implies old disc injury or herniation. Calcification of the nucleus pulposus may present with symptoms of lumbar stiffness, and calcification must reduce the volume of the spinal canal to induce signs of nerve root compression. 20.What is the significance of a lumbar functional radiograph for the diagnosis of lumbar disc herniation? A functional lumbar spine radiograph is a lateral or oblique radiograph taken in flexion or hyperextension, or an orthogonal radiograph taken in left or right flexion. This is particularly useful for patients with low back pain who have a tendency toward spinal instability. Lateral flexion and extension films can show the alignment of the lumbar spine in motion. Mild lumbar slippage is not reflected on a normal lateral radiograph, but can be well reflected on a functional radiograph. In normal individuals, the anterior edge of the lumbar spine is smooth and continuous when the lateral phase is taken with the lumbar spine in anterior flexion. In patients with lumbar disc degeneration, the curve is more irregular and may be trapezoidal. In a normal person, the lines along the posterior edge of each vertebra are smoothly connected to each other, without obvious angulation. In patients with lumbar disc degeneration, the angle between the lines of the posterior edge of the vertebral body is large and discontinuous, especially in segments with severe lumbar disc degeneration. Orthopantomographs taken in left and right flexion can clarify the segments where the main bend in scoliosis exists, because the main bend cannot disappear in lumbar lateral flexion. In contrast, compensatory bending can be corrected by lumbar lateral flexion. Lumbar scoliosis due to lumbar disc herniation is mostly compensatory bending, and its nature is different from idiopathic scoliosis, which can be distinguished by taking functional lumbar spine radiographs.