Scoliosis

　　Scoliosis is a disease in which the spine bulges to one side. There are many reasons that can cause scoliosis, each with its own characteristics. According to the etiology, it can be divided into functional or organic types, or non-structural and structural types.

　　(I) Non-structural scoliosis

　　1, Postural curvature;

　　2, Low back and leg pain, such as intervertebral disc herniation, tumor;

　　3, Unequal length of both lower limbs caused;

　　4, Hip joint contracture caused;

　　5, Inflammatory stimulation (such as appendicitis);

　　6, Hysterical curvature.

　　Non-structural scoliosis refers to temporary lateral curvature caused by certain reasons, which can be restored to normal once the cause is removed. However, if it persists for a long time, it can also develop into structural scoliosis. Generally, in such patients, the lateral curvature can often disappear spontaneously when lying flat, and the X-ray film shows that the spine bones are normal.

　　(II) Structural scoliosis

　　1, Idiopathic

　　The most common, accounting for 75%-85% of the total, the etiology is unclear, so it is called idiopathic scoliosis. Depending on the age of onset, it can be divided into three categories.

　　(1) Infantile type (0-3 years) ① Natural cure type; ② Progressive type.

　　(2) Juvenile type (4-10 years).

　　(3) Adolescent type (>10 years to skeletal maturity).

　　Among the above three types, adolescent type is the most common.

　　2, Congenital

　　(1) Malformation type: Congenital hemivertebrae, congenital wedge-shaped vertebrae.

　　(2) Malsegmentation type.

　　(3) Mixed type, with both of the above two types.

　　Congenital scoliosis is caused by incomplete segmentation of the vertebral column during embryonic development, a bone bridge on one side, incomplete development of one vertebral body on one side, or a mixture of the above two factors, leading to asymmetric growth on both sides of the spine, thus causing scoliosis. It often occurs simultaneously with other deformities, including spinal cord deformities, congenital heart disease, congenital urinary tract deformities, and others. Scoliotic deformities can usually be detected on X-rays.

　　3, Neuromuscular

　　It can be divided into neurogenic and myogenic, which is caused by diseases of the nerves or muscles leading to muscle imbalance, especially the asymmetry of paraspinal muscles on both sides, resulting in scoliosis. Common causes include sequelae of poliomyelitis, cerebral palsy, syringomyelia, progressive muscular atrophy, and others.

　　4, Scoliosis associated with neurofibromatosis

　　5, Scoliosis caused by interstitial lesions

　　Such as Marfan syndrome, congenital multiple joint contractures, and others.

　　6, Acquired scoliosis

　　Such as scoliosis caused by chest surgery such as ankylosing spondylitis, spinal fracture, spinal tuberculosis, empyema, and thoracoplasty.

　　7, Other causes

　　Such as scoliosis caused by metabolic, nutritional, or endocrine reasons.

　　Scoliosis in some patients is discovered incidentally, with clinical deformities that may not be obvious. Severe cases can lead to rotational deformity of the thoracic cage, trunk tilt, depression of the thoracic cage, trunk shortening, and decreased activity tolerance due to decreased thoracic volume, dyspnea, palpitations, indigestion, anorexia, and other visceral dysfunction. If scoliosis is not treated effectively for a long time, symptoms such as traction or compression of the spinal cord and nerves may occur.

　　From the appearance of scoliosis patients, the curvature can produce back bulging deformity, produce a saber-toothed back deformity, some even produce funnel chest or pigeon chest deformity, at the same time, combined with this kind of back deformity, it can be accompanied by imbalance of bilateral shoulder joints or pelvic imbalance, as well as unequal length of both lower limbs, which can cause obvious local deformity, decrease in height, reduction in chest and abdominal cavity capacity, and even cause damage to nerve function, respiratory function, and digestive function; at the same time, for patients with poor development of spinal bone structure, complications such as meningocele, concealed spina bifida, and other nervous developmental abnormalities may occur. In addition, congenital scoliosis may also be accompanied by abnormalities in the cardiovascular system, tracheoesophageal fistula, polycystic kidney, and other multi-organ abnormalities.

　　The etiology of scoliosis is generally divided into congenital and idiopathic in clinical practice. Once onset, it can cause great physical and psychological harm to patients, so we should pay attention to the prevention of this disease in our daily lives:

　　15. The sitting posture must be upright, if you need to sit for a long time, the chair you sit on must have a backrest, and the angle of the backrest cannot be greater than 115 degrees, the buttocks must be close to the backrest, and if you can add a lumbar support cushion to the waist, it can maintain the normal lumbar curvature even better.

　　14. When walking, keep the chest挺 rather than the belly, to avoid the lumbar spine from protruding forward and causing lumbar nerve compression, pregnant women should pay special attention.

　　13. When sleeping, to maintain the normal cervical curvature, the pillow should be changed to a health pillow that conforms to human cervical ergonomics design (conforming to the normal cervical curvature), and avoid sleeping on a high pillow.

　　12. Avoid bending over to pick up heavy objects, it is better to crouch to pick them up.

　　11. Avoid carrying heavy loads on one side.

　　10. When carrying heavy loads, use both shoulders alternately to avoid long-term use of one side to prevent thoracic vertebral curvature.

　　9. Avoid sleeping face down to prevent cervical vertebral curvature.

　　8. Avoid overeating to prevent overweight and increase the burden on the lumbar spine.

　　7. Consume enough calcium to prevent early osteoporosis, calcium-rich foods include cheese, milk, kale, and tofu, etc.

　　6. Appropriate and moderate exercise, to strengthen muscles, increase joint flexibility, and maintain a good posture, prevent bone aging, and slow down calcium loss.

　　Scoliosis is a symptom that can occur congenitally or acquired. Patients should undergo moiré topography examination, routine X-ray examination, electromyography examination, and nerve conduction velocity measurement, etc.

　　I. Moiré topography image examination

　　Wave imaging is a method of using optical techniques to represent vertebral backside deformities through contour maps. If a straight line is drawn from the spinous process of the 7th cervical vertebra to the superior margin of the gluteal furrow as a baseline, the normal wave pattern is symmetrical on both sides of the baseline, with equal numbers of grooves. If there is a deformity in the back, there will be a difference in height on both sides, the number of wave grooves will be unequal and asymmetrical, the more severe the deformity, the greater the height difference on both sides of the back, the greater the difference in the number of wave grooves, and if there is a difference in one or more grooves that indicates a positive wave image.

　　Routine X-ray examination cannot reflect the rib and thoracic deformities caused by spinal rotation. A special grating projection and wavy imaging device for spinal examination is used to capture the different wave patterns on both sides of the patient's back or waist at different heights or with different deformities, which is called a wavy image. A ruler is placed on the positioning frame during image capture, and it is摄入 the same image as the patient's back to serve as a scale for measurement and calculation. For example, a perpendicular line is drawn from the C7 spinous process to the gluteal groove in the image, and the peak points of each wave pattern on both sides are found from top to bottom. The two peak points with the shortest perpendicular distance to the midline and the largest difference in wave pattern lines are found in the line connecting the peak points, and they are set as a and b (the convex side is a). The height difference between a and b is H, and the distance between a and b is (a+b). Based on the above points, the rib hump angle or lumbar hump angle (Hump Angle) can be calculated according to the formula, which is to express the hump deformity formed by the lateral curvature of the spine on the back of the trunk in terms of angle. The actual length of a and b is w = (a+b)/scale, and the height difference between a and b is the difference in wave pattern lines between a and b multiplied by 5 (each wave pattern interval represents a 5mm actual height difference). Then, the hump angle (HA) = atan(H/w). Therefore, the wavy image not only has qualitative significance but also quantitative significance for the judgment of spinal lateral curvature.

　　2. Radiological examination

　　(I) Routine X-ray examination

　　It is as important as physical examination for the diagnosis and treatment of scoliosis. X-ray films help understand the etiology, type, location, size, range, and flexibility of the lateral curvature. According to different needs, other special X-ray examinations can be performed to establish a diagnosis; observe the progression of deformity; find associated deformities; formulate treatment plans, or evaluate the efficacy.

　　1. Upright position examination

　　Standing and sitting positions are the basic poses for X-ray examinations. Standing images can be taken if the patient can stand; if the lower limbs lack the ability to stand or the patient is too young, sitting images are taken. The standard posture is to have the patient's feet together, legs straight, trunk straight, and prevent rotation. After exposure, the anteroposterior view is taken, with the forearm extended forward at 90° (or placed on a bracket) for lateral view filming. Try to include the full length of the spine in one film.

　　2. Flexibility examination

　　After the lateral curvature has been confirmed in an erect position, lateral flexion views can be taken to understand the flexibility of each curvature of the spine. The patient lies on their back and actively contracts their muscles to the maximum extent on the convex side to correct the deformity. Some patients have neuromuscular lateral curvature, without the ability to autonomously contract their muscles, and sometimes the 'pushing method' is used for filming to understand its flexibility.

　　3. Filming under traction

　　The patient is placed in supine position, with the occipital and pelvic straps pulled up simultaneously for filming under traction, currently, filming under suspension traction is more standardized and commonly used, that is, filming the anteroposterior and lateral views with the occipital and pelvic straps in an upright traction position (the criterion is that both feet of the patient just leave the ground) to understand the flexibility of the lateral curvature.

　　4. Spinal rotation reduction radiography (Stagnara position)

　　Structural scoliosis, especially severe scoliosis (over 100 degrees), is often accompanied by spinal rotation. The routine anteroposterior X-ray film cannot truly reflect the degree of deformity, and sometimes it cannot even show the true deformity of the vertebral bodies. Therefore, the ideal method is to透视 under the fluorescent screen, rotate the spine until the scoliosis reaches its maximum degree, and then take a film, or rotate to the point where the apex of the curvature is in true anteroposterior position, to show the true degree of curvature or the true shape of the vertebral bodies.

　　5. Assessment of bone age

　　The treatment of scoliosis, the age of the patient is one of the important reference factors. Understanding the bone age is to assess whether the bones continue to grow. The period of growth and development maturity for girls is about 16 years old, and boys are 1 to 1.5 years later than girls. Therefore, an anteroposterior X-ray film of the patient's left hand and wrist is taken to understand the bone age. Currently, the most commonly used method is the Risser method, which involves taking an iliac crest epiphysis film to understand its epiphyseal maturity. The total length from the anterior superior iliac spine to the posterior superior iliac spine is divided into four segments, counted from front to back. When the epiphysis appears in the first quarter, it is 1 degree; when the epiphysis grows in the first half, it is 2 degrees; when it is 3/4, it is 3 degrees; when the entire length is 4 degrees; and when the epiphysis is completely closed, it is 5 degrees. The closure age is about 24 years old, making it the last bone to close in the body. At this point, the growth and development of the skeleton has stopped, and the deformity of the scoliosis is relatively stable. Sometimes, clear chest and lumbar X-ray films can also be referred to, observing the epiphysis of the vertebral bodies. If the epiphysis is discontinuous, it indicates that bone growth has not been completed. If it has fused, it means that the growth and development of the spine has been completed.

　　(Two) Tomography

　　Plain film tomography can provide a clear view of the scope and nature of the deformity and lesion in specific areas, such as bone nonunion or pseudarthrosis. While conventional plain films may not be clear, tomography can display these features.

　　(Three) Myelography

　　In the treatment of scoliosis, understanding not only the spinal or vertebral deformity but also the presence of any associated deformities within the spinal canal is important. In congenital scoliosis, myelography is almost always performed as a routine examination, with the aim of understanding the neural deformities coexisting with bony deformities. The contrast agent currently most commonly used is Amipaque or Wmnipaque, due to their good contrast performance, safety, and mild reactions. The adult dose is 10-20ml, and generally, lumbar puncture is used. For ascending examination, a foot-high head-low position is adopted, and for descending examination, a head-high foot-low position is adopted. However, when the head is low, it is necessary to prevent the contrast agent from entering the ventricles under the display of the fluorescent screen.

　　(Four) Electron beam computed tomography X-ray scanning (CT)

　　CT scanning has a significant advantage in the diagnosis of spinal, spinal cord, and nerve root lesions, especially for areas that are not clearly visible on conventional X-ray films (such as the occipital-cervical region, cervical-thoracic segment, etc.). Due to its 20 times higher density resolution than conventional X-rays, it can clearly display the fine structures of the vertebrae, spinal canal, and paravertebral tissues. Especially in myelography CT scanning, it can provide valuable information for understanding the true condition inside the spinal canal, the relationship between bone and neural components, and can offer valuable data for surgical treatment.

　　(Five) Nucleus Magnetic Resonance Imaging (MRI)

　　MRI is a new non-invasive multi-plane imaging examination with strong resolution of intraspinal lesions. It not only provides the location and extent of the lesion but also has better resolution than CT for the nature of the lesion, such as edema, compression, hematoma, and spinal cord degeneration. However, it cannot replace CT or myelography, each having its indications.

　　Three, Electrophysiological Examination

　　Electrophysiological examination is of great significance for understanding whether there are coexisting neurological and muscular system disorders in patients with scoliosis.

　　(One) Electromyography Examination

　　Electromyography (EMG) utilizes the bioelectric activity generated by the contraction of striated muscles, which is picked up, amplified, and displayed on a cathode ray oscilloscope, and then drawn on a recording paper. The individual or overall muscle potential waveform is analyzed to understand the state of the motor unit, evaluate and judge the nerve muscle function. During the examination, the patient takes a supine position, the skin of the examined part is disinfected, and the sterile needle electrode is inserted into the muscle to be examined. The insertion potential at the time of needle insertion, the static potential when the muscle is completely relaxed, and the motor unit potential appearing during muscle contraction are observed. Abnormal electromyography includes fibrillation potentials, sharp waves, positive phase potentials, fasciculation potentials, or biphasic potentials, etc.

　　(Two) Nerve Conduction Velocity Measurement

　　It can be divided into motor conduction velocity and sensory conduction velocity. The measurement of motor conduction velocity is to use electrical stimulation to record muscle potentials, calculate the speed of excitation along the motor nerve, that is:

　　Motor nerve conduction velocity (m/s) = distance between two points (mm) / latency difference between two points (ms).

　　The measurement of sensory nerve conduction velocity is to stimulate a point forwardly on the fingers or toes, and record the evoked potential at the proximal part of the body. It can also be stimulated reversely on the nerve trunk, and the evoked potential at the tip of the finger or toe is recorded. The calculation method is the same as above. The factors affecting the conduction velocity measurement are many, and it is advisable to use the healthy side as a control for unilateral lesions.

　　(Three) Evoked Potential Examination

　　Somatosensory evoked potentials (SEP) have certain practical value in judging the degree of spinal cord nerve injury, estimating the prognosis, or observing the therapeutic effect. In recent years, we have adopted the direct placement of stimulation and recording electrodes in the subarachnoid cavity or epidural space to record spinal cord evoked potentials (SCEP) during spinal surgery, for segmental monitoring of the spinal cord. The waveform is stable and clear, unaffected by anesthesia or drugs, and can provide a good monitoring tool for spinal surgery.

　　Four, Pulmonary Function Testing

　　Scoliosis due to vertebral rotation can cause thoracic deformity and fatigue of respiratory muscles, and the expansion of the lungs is also correspondingly restricted. Therefore, scoliosis is often accompanied by pulmonary dysfunction, and the more severe the scoliosis, the more severe the pulmonary dysfunction. According to the preoperative pulmonary function examination of 105 patients with scoliosis by the author, except for 2 cases, all had varying degrees of pulmonary dysfunction. The proportion of patients with vital capacity below 50% was 16%, and the proportion of patients with forced vital capacity below 50% was 30%. Due to postoperative pain, the vital capacity can decrease by 10% to 15% after normal chest or back surgery. Therefore, patients with severe spinal deformities with vital capacity below 40% should first undergo pulmonary function exercises before surgery, and then undergo spinal correction surgery after the pulmonary function improves.

　　Five, X-ray Film Measurement of Scoliosis

　　(I) Scoliosis Angle Measurement

　　1. Cobb method:On the anteroposterior X-ray film, first determine the upper and lower terminal vertebrae of the scoliosis, on the upper end of the main curve, the upper and lower terminal plates of the upper terminal vertebra are inclined to the concave side to the maximum extent, and the lower terminal vertebra on the lower end of the main curve. Draw a horizontal line on the upper edge of the upper terminal vertebra and the lower edge of the lower terminal vertebra, and draw a vertical line perpendicular to each of these two horizontal lines. The angle where these two vertical lines intersect is the Cobb angle, which can be measured by a protractor to determine its specific degree.

　　2. Ferguson method:On the anteroposterior X-ray film, draw a line from the center of the upper terminal vertebra to the center of the apex vertebra, and then draw a line from the center of the lower terminal vertebra to the center of the apex vertebra. The supplementary angle where the two lines intersect is the Ferguson angle.

　　The first two methods are commonly used with the Cobb method, almost unified internationally, but it should be noted that in the diagnosis and treatment follow-up, the same patient's same side curve should use the same terminal vertebra line for measurement, otherwise the conditions are not the same, it is difficult to compare.

　　(II) Vertebral Rotation Measurement

　　In structural scoliosis, there is often associated vertebral rotation. The methods for measuring rotation are:

　　1. Using the spinous process as the landmark pointThat is, on the anteroposterior X-ray film, the spinous process is located at the center of the vertebra is normal. If the vertebral midline to the lateral edge of the vertebra is divided into three equal parts, the spinous process shifts to the concave side with vertebral rotation. A shift of one-third is Ⅰ° shift, a shift of two-thirds is Ⅱ°, and a shift of three-thirds is Ⅲ°. Beyond the vertebral edge is Ⅳ°. If the deviation of the spinous process from the midline is converted into degrees, if the deviation is one-third of half the vertebra, the rotation degree is 15°, two-thirds is 30°, and the projection of the spinous process on the vertebral edge is 45°.

　　2. Using the pedicle as the landmark point (Moe method):On the anteroposterior X-ray film, observe the position of the bilateral pedicles, and divide the hemivertebra into three equal parts as well. The normal pedicles are symmetrical on both sides, located in the outer one-third. If the vertebra rotates, the pedicles are located in the middle one-third for Ⅰ° rotation, in the inner one-third for Ⅱ° rotation, at the midline for Ⅲ° rotation, and rotating beyond the midline to the other side for Ⅳ° rotation. According to the quantitative determination of rotation of 328 vertebrae in patients with scoliosis and normal individuals by the author, and compared with the corresponding X-ray Nash-Moe rotation degree, namely Nash-Moe Ⅰ° rotation, the actual rotation angle of the vertebra is 10.42±2.14 degrees, Ⅱ° is 24.03±3.91 degrees, Ⅲ° is 32.94±4.51 degrees, and Ⅳ° is more than 50 degrees.

　　3. Measurement of vertebral wedge-shaped changesScoliosis patients, as the lateral curvature becomes more severe, produce unequal heights on both sides of the vertebral bodies, that is, wedge-shaped changes. The height on the concave side of the vertebral body decreases. If the height of the vertebral body in the normal anteroposterior X-ray film is divided into 4 degrees, the reduction of one side of the vertebral body height by 0-1/6 is Ⅰ°, 1/6-1/3 is Ⅱ°, 1/3-1/2 is Ⅲ°, and more than 1/2 is Ⅳ°.

　　All checks should be recorded well for use during follow-up.

　　Severe scoliosis can be treated by the method of anterior surgery. Since the anterior surgery is mainly manipulated retroperitoneally, the postoperative intestinal function may be suppressed, resulting in intestinal paresis symptoms. Starting from 6 hours after surgery, start with fluid diet, and on the second day, take 20-30mL of potassium chloride orally, lasting for 2-3 days to promote peristalsis, accelerate the recovery of bowel sounds, and alleviate bloating. If there is no discomfort, you can gradually transition from fluid diet to easy-to-digest, delicious, and nutritionally rich general diet. Eat less and more often, and eat more foods rich in calcium, such as shrimp shells. If nausea and vomiting occur frequently, be警惕 the occurrence of superior mesenteric artery syndrome.

　　The treatment of scoliosis can be done not only by conservative methods but also by surgical methods. The main surgical treatments for this disease are mainly six kinds:

　　1. Harrington surgery

　　Harrington first reported in 1962 the use of metallic internal fixation devices to support or apply pressure for the correction of scoliosis, which consists of mainly two parts: one is a rod, and the other is a hook. Placed on the concave side of the lateral curvature, it uses a tension rod, and on the convex side, it uses a pressure rod. The proximal end of the tension rod is toothed to allow placement inside the hook, which only allows tension and not reversal. Its tail end is square to prevent rotation after insertion into the lower hook. The pressure rod is thinner and more elastic; it is threaded throughout its length. The upper hook of the tension rod is a circular hole, and the tail end hook is a square hole. The Rochester type of the pressure rod has a groove on the back, which makes it easy to place the pressure rod and washer inside. The upper hook of the tension rod is generally placed between the costovertebral joints of the thoracic vertebrae, the lower hook is placed on the superior margin of the lumbar vertebral plate, the upper hook of the pressure rod is placed on the costotransverse joint, and the lower hook is placed on the inferior margin of the lumbar vertebral plate. The Harrington device has good longitudinal support performance, and its effect on Cobb angle greater than 50° is small, that is, the angle is small, and the correction force is poor. However, excessive angles can be corrected using two tension rods or in combination with the pressure rod.

　　The operation method of the Harrington surgery has been internationally standardized. After the patient is fully anesthetized and placed on the Hall-Relton surgical brace in a prone position, the skin is sterilized, covered with sterile film, and before skin incision, 1:400,000 adrenaline solution is injected subcutaneously and into the muscle to reduce bleeding. A straight incision is made on the upper and lower spinous processes of the segment to be fused, and the soft tissue of the spinous process and both sides of the laminae is stripped off under the periosteum until the lateral and transverse processes of the ribs or the costotransverse joint are exposed. The muscles on both sides are distracted with an automatic distractor, and an upper joint is found on the convex side of the lateral flexion, which is incised and an upper hook is placed. A lower hook is placed on the superior margin of the lower terminal vertebra, and an intermediate hook is placed above and below the hooks. The external fixation distractor is placed between the upper and lower intermediate hooks, and the screw of the distractor is rotated to distract the lateral flexion from the concave side. A distraction rod of appropriate length is selected and inserted into the holes of the upper and lower hooks, removing the external distractor. The upper hook is then raised 1 to 2 notches on the ridge-like step of the upper end of the distraction rod to achieve maximum correction. Then, an intraoperative awakening test or evoked potential monitoring is performed to prove that there is no overcorrection. Finally, the spinous process, laminae, and small joints of the segment to be fused are decorticated to create a bone graft bed, and then iliac bone grafting or combined with allograft bone grafting is performed. Before closing the wound, 1 to 2 negative pressure drainage tubes are placed to reduce hematoma and prevent infection.

　　When the Harrington distraction rod and the compression rod are used together, the compression rod should be placed first. Currently, the Harrington distraction device for correction is often combined with Luque segmental laminae subligamentous wire fixation to reduce complications such as hook disengagement and rod breakage after simple Harrington surgery.

　　2. Luque surgery

　　In 1976, Luque from Mexico first reported this method, in which two 'L'-shaped metal rods were placed on both sides of the lateral flexion segmental laminae. The short arm of one metal rod was inserted into the lateral flexion, into the spinous process of the upper terminal vertebra, and the short arm of the other 'L'-shaped metal rod was inserted into the lateral flexion below the lower terminal vertebra into the next spinous process. In this way, the two rods form a rectangular shape, controlling the sliding or rotation of the metal rod up and down, and removing all inter spinous ligaments, yellow ligaments, and opening the interlaminae foramen. A steel wire was passed through each interlaminae foramen, under the laminae, and out through the adjacent interlaminae foramen. The steel wire passing through the lower laminae of each segment was tightened on the metal rod on both sides, thereby completely fixing the laminae and metal rod together.

　　Luque surgical steps: position, incision, exposure are the same as Harrington surgery.

　　1) Lamina windowing: After removing the interspinous ligament or part of the spinous process, expose the yellow ligament, use a bone nibbler to bite a small hole first, insert a nerve dissector to separate the epidural space, and then insert a small beveled Kerrison lamina咬骨钳 into the epidural space, gently press the epidural fat downward, lift the yellow ligament, open a 0.5cm diameter window in the lamina space for the wire to pass through.

　　2) Sublaminar wire penetration: Cut the soft, inelastic wire with a diameter of 0.8 to 1.0mm into lengths of about 50cm, fold it into double strands, leaving a circular small hole at the top, bend the top of the double-strand wire into an arc with the spacing between the two laminae as the diameter, insert the top of the arc-shaped wire into the opening between the next laminae, pass through the epidural space, and adhere to the sublaminar space. It comes out through the window between the upper laminae, hooks the top hole of the wire with a small hook, and pulls it out under the lamina, cuts off the top of the double-strand wire, making it a single strand, separates the left and right sides, and prepares for fixing the 'L' shaped rod.

　　3) Fixing the 'L' shaped rod: Generally, an 'L' shaped rod is placed on the concave side first, and a wire is wrapped around the metal rod, then the wire is twisted and tied up one by one from top to bottom. During the twisting process of the wire, the assistant can gently push and press the convex side to facilitate correction, and then place another 'L' shaped rod on the convex side. In the same way, tie each wire that passes through the sublaminar space one by one from top to bottom, so that the two 'L' shaped rods, using the apex of the lateral curvature as the fulcrum, like a splint, correct the lateral curvature.

　　Bone grafting, fusion, and similar Harrington surgery, Luque surgery fixation is reliable, the incidence of pseudoarthrosis after surgery is low, but each wire passing through the epidural space increases the opportunity for spinal cord injury.

　　3. Harri-Luque spinous process base bone clip wire fixation method

　　Since 1985, the Harrington and Luque combined instrument has been adopted, but not the sublaminar wire fixation. Instead, two parallel 1.5mm diameter holes are drilled parallel to the lamina at the thickest part of the spinous process using a perforator, and the two ends of the wire with bone clips are threaded through the two holes from one side to the other (the bone clips are pre-prepared), and the wire passing through is used to fix the Harrington rod or Luque rod on this side. In this way, the wire passes through the bone clip from the Wisconsin method originally as a transverse tensile force, becomes a pressure of equal magnitude and opposite direction against the spinous process, thereby greatly enhancing the fixing ability of the wire. The author has proved through biomechanical testing and clinical comparison with more than 100 cases that the correction rate and fixing force in this direction are not weaker than the Luque method, but it reduces the complexity of sublaminar wire penetration in the Luque method, and avoids or reduces the opportunity for direct injury to the spinal cord and nerve.

　　4, Dwyer surgery

　　In 1969, Dwyer in Australia adopted a surgical method for correcting spinal curvature from the front of the vertebral body. This operation is mainly suitable for scoliotic deformities below L1, especially for cases with severe absence or deformity of the vertebral plate, which cannot be hinged. The operation usually starts with a combined thoracoabdominal incision on the convex side, resecting the 10th rib to enter the thoracic cavity, exposing the anterior lateral part of T11~L5 vertebrae extraperitoneally, ligating the blood vessels running across the vertebrae, longitudinally incising the anterior longitudinal ligament and periosteum, and stripping the periosteum to both sides, exposing the vertebral bodies, resecting all intervertebral discs within the scope of scoliosis, inserting a hole-screw into each vertebral body, the steel wire passing through the hole, tightening the steel wire to bring the vertebral bodies closer together, making the intervertebral space on the convex side disappear, straightening the spine, flattening the screw so that the steel wire cannot retract, correcting the curvature. This method has satisfactory correction, but many complications.

　　5, Zielke surgery

　　The Zielke device is actually an improved Dwyer device, and its approach is also an anterior approach. The biggest advantage of this method is that it has a large degree of correction and can rotate; the number of fixed segments is small, and there is only compression on the deformed segment without any expansion effect, so there are fewer opportunities for nerve traction injury.

　　6, C.D surgery

　　In 1984, French Cotrel and Dubousset reported their new type of spinal curvature correction and fixation device, mainly suitable for idiopathic scoliosis during adolescence, and is one of the most effective fixation devices in current posterior spinal deformity correction surgery. However, the method is complex and has many complications.