Spinal tuberculosis complicated with paraplegia

　　One. Anatomical points

　　1. Composition of the spinal canal

　　The spinal canal is formed by the vertebral foramina of the individual vertebrae. The superior end starts from the foramen magnum, and the inferior end ends at the sacral hiatus. The anterior wall is formed by the vertebral bodies, intervertebral discs, and posterior longitudinal ligaments, while the posterior wall is formed by the vertebral arches and cruciate ligaments. The spinal canal is widest at the lower cervical and lumbar regions, while the middle cervical and thoracic segments are narrower.

　　2. Content of the spinal canal

　　(1) The spinal cord has three meninges, from outside to inside, they are the dura mater, arachnoid, and pia mater, which are completely connected to the three layers of the brain's meninges.

　　(2) The spinal meninges cavity

　　① The subarachnoid space is located between the arachnoid and the dura mater, communicating with the intracranial ventricles and subarachnoid space. It is filled with cerebrospinal fluid. The subarachnoid space at the L2 to S2 level is wider and larger, known as the terminal cistern. Here, there is more cerebrospinal fluid, with only the cauda equina and filum terminale in the cavity. Lumbar puncture and anesthesia are performed through this cavity.

　　② The epidural space is the cavity between the dura mater and the spinal canal. It is filled with fatty tissue and venous plexuses and is in a negative pressure state.

　　(6) The intraspinal venous plexus is located in the extradural space of the dura mater, divided into anterior and posterior plexuses, respectively located on the anterior and posterior walls of the spinal canal, receiving the blood回流 from the vertebrae and spinal cord, and draining into the vertebral veins at the intervertebral foramina. These veins注入 into the vertebral veins in the neck, into the azygos and hemiazygos veins in the chest, and into the lumbar veins in the lumbar region.

　　3. Blood supply to the spinal cord The main sources of blood supply to the spinal cord are as follows:

　　(1) The anterior spinal artery originates from the vertebral artery, merging into one branch on each side, descending along the anterior median fissure of the spinal cord, giving off branches along the way that penetrate the spinal cord to reach the anterior horn, lateral horn, central gray matter, anterior funiculus, and lateral column deep, supplying the anterior two-thirds of the entire spinal cord.

　　(2) The posterior spinal artery This artery originates from the vertebral artery or posterior inferior cerebellar artery, with one branch on each side descending along the lateral sulcus of the posterior spinal root, anastomosing with the arteries of each segment and the posterior root arteries, mainly supplying the posterior one-third of the spinal cord.

　　(3) The arterial arcade, also known as the coronary artery, is a vascular plexus where the branches of the anterior and posterior spinal arteries and the root pia arteries anastomose on the surface of the spinal cord. The coronary arteries are denser at the cervical and lumbar enlargements and sparser in the thoracic segment. The arteries are perpendicular to the surface of the spinal cord, with branches entering the spinal cord along the soft spinal septum.

　　(4) The root arteries originate from the ascending cervical artery, intercostal arteries, and lumbar arteries, entering the spinal canal through intervertebral foramina and anastomosing with the anterior and posterior spinal arteries, thus continuously supplementing and strengthening the blood supply to the spinal cord during its descent. The blood supply from different sources to the spinal cord can reach 6 to 10 roots, with 0 to 6 roots located in the cervical spinal cord. There are 2 to 4 roots in the thoracic spinal cord, 1 to 2 roots in the lumbar spinal cord, among which one large anterior root artery is called the lumbar enlargement artery (Adamkiewiez artery). The posterior root arteries are about 10 to 23 in number, distributed on the dorsal side of the spinal cord, and anastomosing with a pair of spinal posterior arteries. The root arteries are often more numerous on the left side than on the right side in the thoracolumbar segment.

　　(5) The transitional area of different blood supply sources between different segments of the spinal cord is most prone to ischemic disorders. For example, the upper thoracic segment of the spinal cord is mainly supplied by intercostal artery branches. When adjacent several intercostal artery branches are injured or ligated, the anterior artery branches supplying the blood of this segment of the spinal cord are insufficient, especially the fourth thoracic segment of the spinal cord is most susceptible to damage. Similarly, the first lumbar segment is also the distribution and transitional area of the superior and inferior roots, which is easy to be damaged.

　　Secondly, the causes and classifications of paraplegia due to spinal tuberculosis

　　1, Active type of paraplegia due to lesion

　　The cavity fluid, caseous material, and granulation tissue (soft compressive material) in the focus exert a pressure of 2～2.66Pa (15～20mmHg) on the spinal cord; local vascular thrombosis of the dead bone or necrotic vertebral disc (hard compressive material) leads to spinal cord edema; in very few cases, tuberculosis granulation tissue penetrates the dura mater, causing tuberculosis spinal cord myelitis (Hodgson et al., 1967) and other comprehensive reasons lead to paraplegia. This type accounts for about 89% of paraplegia cases, and the treatment effect is generally good, except for cases with vascular thrombosis and tuberculosis spinal cord myelitis.

　　2, Cured type of paraplegia due to lesion

　　In the late stage of the disease, in addition to the fibrosis and scar formation around the spinal cord by granulation tissue in the spinal canal, there may be pathological displacement or semi-displacement of the vertebral bodies, especially in the upper part of the cervical and upper thoracic segments and the thoracolumbar segments. After the vertebral spine develops a posterior突出的畸形，合并椎管拉长，脊髓过度延伸紧张跨于椎管前方的骨嵴上，due to various reasons such as atrophy or degeneration, wear and tear, etc., leading to paralysis. This type accounts for about 11% of paraplegia cases and has a poor prognosis.

　　Firstly, neurogenic bladder dysfunction

　　The voiding function of the bladder requires close coordination between the detrusor muscle and the urethral sphincter. After spinal cord injury, the brain and sacral中枢 lose control over the detrusor muscle and urethral sphincter, that is, the central nervous system cannot control the voiding function, which is collectively referred to as neurogenic bladder dysfunction. Patients often have urinary tract infections due to urinary dysfunction or even loss of function.

　　In the past, voiding dysfunction was divided into two types: autonomous bladder and reflex bladder. Recently, according to the condition of bladder detrusor function, it is more detailedly divided into the classification of neurogenic bladder:

　　1, Detrusor reflex hyperactivity, according to the function of the sphincter, is divided into:

　　(1) Normal coordination of the sphincter, its manifestation is urgency and frequent urination.

　　(2) Discoordination of the external sphincter, manifested as urinary retention.

　　(3) Discoordination of the internal sphincter, manifested as urinary retention.

　　2, Absence of detrusor reflex

　　(1) Normal coordination of the sphincter, manifested as urinary retention.

　　(2) Spasm of the external sphincter, manifested as urinary retention.

　　(3) Spasm of the internal sphincter, manifested as urinary retention.

　　(4) Denervation (relaxation) of the external sphincter, manifested as urinary incontinence.

　　Secondly, clinical manifestations

　　A strong bladder with hyperactive detrusor reflex, with normal coordination of the sphincter, manifests clinically as urgency and frequent urination. Most patients in the early stage show symptoms of urinary retention. In addition to patients with denervation (relaxation) of the sphincter, the rest of the patients, regardless of whether the detrusor is strong or weak, cannot expel urine because their internal and external sphincters cannot coordinate. When the bladder is filled with urine, its internal pressure exceeds the tensile strength of the sphincter, and urine leaks out. In the later stage, the sphincter becomes relaxed, especially in patients who have long-term indwelling catheters, and urinary incontinence occurs.

　　1. Bedsores

　　(1) Degrees of bedsores

　　Local skin redness and hardness I°; epidermis purple-red, with blisters not reaching the subcutaneous tissue II°; bedsores reach the subcutaneous tissue, sometimes exposing muscle or tendon III°; local tissue necrosis reaches the bone IV°.

　　(2) Common sites of bedsores

　　Below the paraplegia level, skin sensation disappears, and the skin over the prominent bones is prone to occur. The common sites when lying flat are the sacrum, the two greater trochanters, and the scapular area; when lying prone for a long time, the anterior superior iliac spine and the front of the patella can occur bedsores.

　　2. Defecation dysfunction

　　(1) Paraplegia patients have defecation dysfunction, mainly manifested as constipation. Research has shown that the peristalsis order of the ascending colon, transverse descending colon, and sigmoid colon in patients is no different from that in normal people. The cause of constipation is due to the uncoordinated action of the anal sphincter, and the anal sphincter is tense during defecation. For such cases, anal suppositories are appropriate, rather than using laxatives or using fingers to dig out fecal masses.

　　(2) Due to constipation, patients often suffer from abdominal distension, especially those with a high level of paralysis, who are more uncomfortable. After constipation is relieved, abdominal distension can improve.

　　First, the main function of the spinal cord

　　It is the control of the three functions of movement, sensation, and sphincter by the cerebral cortex, the transmission of sensation, and the control of urination and defecation. Paraplegia is mainly characterized by active movement dysfunction. Some scholars divide the degree of motor dysfunction in paraplegia patients into four levels, which is convenient for observing the development of paraplegia during treatment and the effect after treatment.

　　1. The patient walks normally, feels strong in the lower limbs, and examination shows or does not show clonus, and the plantar reflex is pathological and positive.

　　2. When walking, the patient's muscles are tense and spastic, weak, and movements are not coordinated. Whether or not crutches are needed, the patient can walk. Examination shows spastic paresis of the limbs.

　　3. Lower limb muscle weakness prevents walking, and the patient is forced to stay in bed. Examination shows an extended type of paraplegia, with about 50% of cases with sensory impairment.

　　4. Patients with flexion-type spastic paraplegia have more than 50% of patients with sensory impairment, and they often have bedsores or even more sphincter dysfunction, including soft瘫.

　　Second, Paraplegia Index

　　1. Divided according to the degree of loss of the three functions of the spinal cord, represented by the three indices of 0, 1, and 2. 0 represents normal or nearly normal function, 1 represents partial loss of function, and 2 represents complete loss or nearly complete loss of function. The degree of loss of these three functions is not completely parallel and consistent. It is common for the voluntary movement of both lower limbs to be completely lost while the sensory and sphincter functions can still exist. For the purpose of comparing before and after treatment, detailed records should be made.

　　2. For example, if a patient's lower limb motor function is nearly completely lost, the index is 2. If the patient's sensation is dull but not completely lost, the total paraplegia index of the patient is 4. After treatment, if the patient's sphincter function and sensory disorder are completely restored, but the motor function is not restored, the total paraplegia index is 2, indicating that the treatment plan is correct and effective and can continue.

　　3. Paraplegia index has its advantages, as the classification is relatively few, and the degree of loss of the three functions is only roughly represented, but it is still a useful indicator.

　　3. Localization diagnosis of spinal cord compression

　　Determining the upper and lower limits of the focus is usually not difficult. The X-ray film can locate the vertebral destruction and paravertebral shadow enlargement. However, when the X-ray film shows that the paravertebral obstruction extends to 4-6 vertebral body lengths and the vertebral bone destruction is not obvious, a detailed neurological examination should be performed, and the results of other imaging examinations should be combined to determine the level of longitudinal compression.

　　1. Determine the upper limit of the spinal cord lesion: radiculopathy has great significance. Radiculopathy is the manifestation of direct stimulation of the sensory posterior root, with dull pain, shooting pain, spreading along the nerve root, and the spreading area is roughly consistent with the distribution area of the lesion root. It is often accompanied by cerebrospinal fluid impact pain (i.e., pain is exacerbated during coughing, sneezing, or exertion).

　　2. Determine the lower limit of the spinal cord lesion based on the changes in reflexes, the highest segment of reflex hyperactivity can usually infer the lower limit of the lesion, for example, if the diaphragm is paralyzed (C4) but the triceps reflex is hyperactive, it can indicate that the lesion involves C4 but has not yet involved C5-6.

　　(1) The Babinski sign: Stimulate the outer edge of the sole of the foot with a blunt object; in normal people, it causes the five toes to curl downwards; when there is a lesion of the pyramidal tract, there is extension of the thumb, accompanied or not accompanied by the fan-shaped spread of the other four toes, which is positive. In most cases, it indicates an aggressive lesion of the pyramidal system, and the interruption of the connection between the low-level motor apparatus and the cerebral cortex.

　　(2) The Chaddock sign: Stimulate the lateral edge of the foot with a blunt object, near the junction of the foot back and palm, and the reflex is the same as the Babinski sign, with similar sensitivity and significance.

　　(3) The Oppenheim sign: The examiner uses the thumb and index finger to press the anterior aspect of the lower leg tightly, push downward from above, and the reaction is the same as the Babinski sign, which is toe extension.

　　(4) The Gordon sign: The examiner firmly grasps the gastrocnemius muscle to cause the foot to extend.

　　(5) The Hoffmann sign: The examiner supports the patient's wrist with the left hand, holds the patient's middle finger with the index and middle fingers of the right hand, and lightly taps with the thumb to elicit a flexion reaction of the patient's thumb and other fingers.

　　Active treatment of tuberculosis, strengthening physical fitness, and preventing the spread of tuberculosis bacteria are the key to the prevention and treatment of the disease. Go to bed early and get up early, exercise the body. Insufficient sleep can reduce the body's immune function and is also prone to anger and internal injury. Maintain a peaceful mind. In spring, it is taboo to be angry, do not be too impulsive in dealing with things, and always maintain a peaceful mind. Quit smoking, drink less alcohol and coffee. Smoking is most likely to damage the surface barrier of the respiratory tract, trigger disease attacks. Alcohol, tobacco, and coffee will stimulate nerve excitation, and some people want to use them to 'relieve tension and fatigue', but in fact, they weaken the body's ability to resist diseases.

　　1. Imaging examination

　　1. X-ray film

　　The vertebral anteroposterior and lateral radiographs showing paravertebral shadow enlargement and obvious vertebral destruction usually indicate the level of spinal cord compression. If the paravertebral abscess extends to 4-6 vertebral body lengths, and the level of bone compression needs to be combined with signs and symptoms to determine. It is necessary to perform myelography, CTM, or MRI, etc., when necessary.

　　2, Myelography

　　Show signs of epidural compression: The main feature is that the断面 of the obstruction site in the anteroposterior film can present brush-like or irregularly concave and convex, but without patchy filling defects. In the lateral view, the displacement of the contrast agent at the compressed site increases the distance from the bony spinal canal or filling defects, and the contrast agent in the subarachnoid space becomes thinner or discontinuous, showing patchy or small cup-shaped filling defects, or scattered small patchy filling defects, showing complete obstruction or partial obstruction, which is not significantly related to the degree of paraplegia (complete or partial).

　　3, CT:It is more valuable for localizing the compression caused by small dead bones.

　　4, MRI

　　(1) In patients with severe paraplegia such as flexion spasm type, atonic paraplegia, and curative focal paraplegia, in addition to X-ray routine film shooting, MRI examination is the first choice. It shows low signal on T1-weighted images and relatively high signal on T2-weighted images, and can show the location of the vertebral abscess and the extent of invasion into the vertebral canal. The sagittal combined with axial plane can accurately show the position of the spinal cord compressed by pus or granulation tissue. When the image shows that 60% of the epidural space above the cauda equina is compressed, general clinical examination does not have varying degrees of spinal cord nerve dysfunction.

　　(2) MRI may occasionally show cystic changes in the spinal cord on the sagittal plane of the T1-weighted image. In the case of curative paraplegia with病灶, the spinal cord becomes thin and atrophic at the most severe site of posture deformation on the sagittal plane of T1-weighted and T2-weighted images, and occasionally there is an abnormal striped signal in the spinal cord itself on the T1-weighted image.

　　2, Somatosensory Evoked Potentials (SEP) monitoring of spinal cord function

　　In the past decade, SEP technology has been used in the monitoring of spinal cord function during surgical decompression for traumatic or pathological paraplegia and correction of scoliosis. In spinal surgery, the spinal cord may be subjected to varying degrees of compression, traction, vibration, or changes in the amount of spinal cord blood perfusion, which may cause sensory and motor impairments in patients after surgery. Therefore, it is very important to timely identify and handle problems by awakening patients during surgery or/and SEP monitoring of spinal cord function. It is worth mentioning that intraoperative SEP monitoring may present false-negative results, so it is necessary to perform an awakening patient test at the same time.

　　1, SEP intraoperative monitoring method

　　(1) At present, there are many types of instruments and equipment on the market. The following points should be noted when purchasing: ①Miniaturization; ②Strong anti-interference ability; ③Clear, stable, and strong reproducibility of signals; ④Flexible software system for graphic analysis and measurement.

　　(2) The amplification gain of the monitoring parameter amplifier is 20-400,000 times, the passband of the filter is 1-1000Hz; the pulse width of the stimulator is 0.1-0.5ms, the frequency is 2.5 times per second; the stimulation intensity is adjusted to produce a clear plantar flexion of the ankle joint before anesthesia. After the administration of anesthetic drugs, due to the effect of muscle relaxants, the same amount of electrical stimulation does not produce ankle joint movement. It is appropriate to increase the stimulation intensity, and the output can be selected from 10-30mA in current mode, and adjusted to 20-60V in voltage output mode. The stimulation intensity should not be too high to avoid nerve damage. The superposition times are 200-500 times, the analysis duration is 200ms. In patients with spinal cord injury, the peak latent time of SEP prolongs, sometimes exceeding 200ms, and is mistakenly considered as the disappearance of SEP. Flexible application should be made during monitoring.

　　(3) The negative pole of the stimulation and recording site is 3 cm anterior and below, and the recording site uses the 10/20 system of the International Electroencephalography Society. It is 2 cm posterior to the Cz point, with the reference electrode on one side of the auricle. Both the stimulation and recording electrodes use stainless steel needles.

　　2. Indicators for SEP spinal cord monitoring

　　Both the peak latency and amplitude of SEP can be used as indicators for monitoring. It is generally believed that the P1 peak latency in the various waves is more stable and continuous. The peak latency of SEP waves changes from normal to abnormal delay during surgery, with the order of N2, P2, N1, P1, and during recovery, the order is reversed, P1, N1, P2, N2. However, there are also cases where only P1 is seen and abnormal changes occur.

　　3. Impact of surgical manipulation on SEP

　　When performing decompression surgery for spinal tuberculosis complicated with paraplegia, the impact of surgical operations on the spinal cord can be summarized as follows: ① surgical manipulation vibration or decompression of the spinal cord; ② in patients with late-onset paraplegia, during surgery, resection of bone to expose the spinal canal, extensive resection of bone around the spinal canal may be related to the destruction of residual blood supply; ③ SEP changes or even disappear when washing the spinal cord with saline below 20°C; ④ after separating the epidural fibrous scar tissue during surgery, SEP changes significantly. Of course, some of the above reasons may exist simultaneously and have a comprehensive impact on the function of the spinal cord. Overall, the above factors require accurate, delicate, and moderate decompression to achieve better surgical outcomes.

　　4. Relationship between SEP examination results and prognosis during surgery

　　(1) According to the examination data, among 86 cases of incomplete paraplegia with spinal tuberculosis and paraplegia, 93% had SEP; among 53 cases of complete paraplegia, 64% had not disappeared SEP. This indicates that paraplegia caused by chronic compressive injury has multiple incomplete spinal cord injuries, and there is a gradual process between SEP normal and disappearance, mainly manifested as an elongation of peak latency and a decrease or even an increase in amplitude. In severe cases, the elongation of peak latency is significant, but we found that there is no strict correlation between peak latency and clinical signs.

　　(2) Spinal tuberculosis complicated with paraplegia has early compressive injury to the spinal cord, mainly characterized by an elongation of the peak latency. Patients with spinal tuberculosis and paraplegia who have disappeared SEP before surgery generally have poor prognosis; conversely, the prognosis is better. Whether SEP can appear or improve after decompression of the spinal canal is related to the duration of SEP disappearance before surgery. If surgery is performed within 1 to 3 weeks after SEP disappearance, SEP improvement can be seen during spinal canal decompression surgery, and 87.5% of the patients have varying degrees of functional recovery after surgery.

　　Three, lumbar puncture cerebrospinal fluid dynamic test

　　1. Quckenstedt test

　　This is a method to check whether there is obstruction in the subarachnoid space of the spinal canal. After a routine lumbar puncture, one person wraps a blood pressure gauge air bag around the patient's neck, one person records, and the operator connects the pressure gauge. The initial pressure and water column height are measured, and then the assistant inflates the blood pressure gauge to 2.67kPa (20mmHg). After that, the pressure is reported every 5 seconds until it no longer rises. The assistant quickly releases the air bag and still reports the pressure every 5 seconds until it falls back to the original level or no longer falls. Subsequently, the test is conducted with an increase of 5.33kPa (44mmHg) and 8.00kPa (60mmHg), and the same records are made. Finally, the results are plotted on a curve.

　　(1) The subarachnoid space is unobstructed, and the pressure rises to the highest point within about 15 seconds after the neck is compressed, and falls back to the initial pressure level within about 15 seconds after the pressure is released. When the pressure is increased to 8kPa (60mmHg), it can rise to about 66.67kPa (500mmHg).

　　(2) In the case of partial obstruction of the subarachnoid space, the pressure in the neck rises and falls slowly after the postoperative pressure is applied, or the rise in pressure is normal while the fall is slow, and the final pressure does not fall to the original level.

　　(3) The subarachnoid space is unobstructed, and the pressure is increased until it reaches 8kPa (600mmHg) without rising.

　　(4) Cerebrospinal fluid is normally colorless and transparent, with a cell count not exceeding 10, and protein quantification of 20% to 40mg%. During obstruction, cerebrospinal fluid appears slightly yellow and transparent, and the protein content can increase to several hundred milligrams%. Sugar and chloride are mostly normal, and the cell count does not change much. If the cell count also increases significantly, it may be tuberculous myelitis (Hodgson 1967).

　　2. Clinical significance

　　(1) There is no need to perform decompression surgery for patients without obstruction before the operation. If there is obstruction before the operation and the postoperative condition is unobstructed, although paraplegia has not recovered, it is not necessary to perform another surgery. If the postoperative condition is still unobstructed but paraplegia has not recovered, it indicates that the decompression is not complete, and another decompression surgery should be performed.

　　(2) This test is simple and easy to perform, but according to the research data of Guan Hua, it is not completely consistent with myelography. It is necessary to perform myelography to verify when necessary.

　　(3) Perform this test before, during, and after the decompression surgery in the spinal canal, and compare before and after the operation. This can monitor whether the decompression is satisfactory and help improve the efficacy of the surgery.

　　1. Note:Select foods that are rich in nutrition and easy to digest, which must meet the supply of protein, inorganic salts, total calories, and the like. Protein should be 1.5 to 2g/kg body weight per day, with 50% of dietary protein coming from legumes and animal protein. Fish and meat contain about 15% to 20% protein, eggs contain 11% to 14%, soybeans contain about 40% protein, and cereal grains contain 7% to 10% plant protein.

　　2. Note:Dietary fiber, increase gastrointestinal motility, and food should not be too fine to avoid constipation. For example: coarse grains (corn, millet, etc.), root vegetables, and seaweed.

　　First, anterior and lateral decompression of the vertebral canal

　　First proposed and designed by Capner, later improved by Alexander (1946) and Dott (1947).

　　1. Position

　　Lay on the side, with the trunk inclined forward to form a 60° angle with the operating table. Choose the side with a larger abscess and more severe paraplegia as the surgical side. The lower limbs are flexed at 45°, the knees are flexed at 90°, and soft pillows are placed between the lower limbs. The knees and pelvic restraints are fixed to maintain the position.

　　2. Anesthesia

　　Tracheal intubation for general anesthesia.

　　3. Operating steps

　　(1) The incision is made on the lateral side of the spine on the surgical side, centered on the diseased vertebra, in the form of an arc or straight line. The apex of the arc incision is 8cm from the midline of the process, with an incision length of 12 to 14cm.

　　(2) Incise the skin, subcutaneous tissue, superficial and deep fascia, and then sequentially incise the first layer of trapezius, latissimus dorsi muscles, and the second layer of rhomboid, and lower serratus muscles along the incision direction.剥离并向外侧牵引，在距离棘突4～5cm，即骶棘肌较薄处纵行切开，分别将该肌向两边牵开，就可见到与病椎相对应需要切除的2～3根肋骨近端。沿着病椎相连肋骨周径将骨膜肃离，直至肋骨颈和横突，并在肋骨颈处切断，距横突外侧6cm剪断肋骨另一端，取出肋骨，用圆头骨膜剥离器沿肋骨，将其内下面骨膜剥开，注意勿撕破胸膜，充分暴露肋骨头，利用横实为支点，撬出肋骨并没有，此时间即可见脓液溢出，吸尽脓液。同样方法切除其上、下方肋骨，沿肋骨床与胸膜间隙，将胸膜向前钝性推开扩大直到病椎帝及椎前，刮除病灶中内容物、干酪物质和死骨。

　　(3) Protect the intercostal nerve and ligate the intercostal vessels. Guided by the intercostal nerve, locate the intervertebral foramen, expand it with a small Kirreson osteotome, and then remove the pedicle. Expose the lateral aspect of the vertebral canal, where the spinal cord can be seen. Follow the same method to remove the upper and lower ribs and pedicles, with the number of ribs removed determined by the extent of the lesion, generally 2 to 3. At this point, the posterior aspect of the diseased vertebra is the lateral anterior aspect of the vertebral canal. Gently scrape and cut the caseous, dead bone, or necrotic disc material that compresses the spinal cord, being careful not to touch the spinal cord. Also, remove the tuberculous granulation tissue surrounding the spinal cord dura and the fibrous scar that compresses the spinal cord in a ring shape. If the posterior process of the diseased vertebra severely compresses the spinal cord, or if part of the posterior process is resected to achieve complete decompression of the spinal cord. After decompression, the surface of the spinal cord (cured lesion type) can be covered with free fat slices to prevent scar formation and subsequent compression of the spinal cord.

　　Two, Thoracotomy lesion removal combined with anterior and lateral decompression of the spinal canal

　　1. Anesthesia

　　For patients with tuberculosis at the 2nd to 3rd to 4th thoracic vertebrae or tuberculosis at the 11th to 12th thoracic vertebrae, general anesthesia is administered by inappropriate means to insert a bronchial tube. During surgery, the lung on the surgical side atelectasis to make the surgical field spacious and easy to operate.

　　2. Position

　　Lateral position, the trunk and both upper limbs are fixed as before.

　　3. Operating steps

　　(1) The posterior and lateral incision of the chest is centered on the thoracic vertebral lesion, and an incision at an appropriate level is selected. Taking patients with tuberculosis at the 7th to 9th thoracic vertebrae and paraplegia as an example, enter the chest from the side with severe paraplegia and large paravertebral abscess by excising the 7th rib; for patients with tuberculosis at the 10th to 11th to 12th thoracic vertebrae, enter the chest by excising the 9th or 10th rib to perform lesion removal and spinal canal decompression surgery.

　　(2) For the steps and methods of surgical exposure of the thoracic vertebral lesion, please refer to the relevant chapters.

　　Three, Anterior and lateral decompression of the spinal canal

　　1. A transverse incision is made along the side of the lesion vertebral body in the direction of the cut rib head and neck, perpendicular to the longitudinal incision for removing the paravertebral abscess, forming a T-shape.

　　(1) Thoracotomy lesion removal and anterior and lateral decompression surgery.

　　(2) The position of the transverse incision for decompressing the spinal canal.

　　2. The distal ends of the ribs and the rib heads are stripped from the transverse incision, and the arch roots of the upper and lower vertebrae are excised. In this process, the transverse process, upper and lower articular processes, and vertebral lamina on the surgical side are not excised to maintain the stability of the spine.

　　3. The methods for removing the spinal cord tuberculosis materials are the same as those described in the relevant chapters and will not be repeated.

　　4. According to the condition of vertebral body destruction, the excised rib or iliac bone block can be used for intervertebral bone grafting to reconstruct the stability of the spine. After thorough hemostasis of the vertebral lesion, the T-shaped incision next to the vertebral column is flushed clean, and the entire layer is sutured with silk thread. A closed drainage tube is placed at the 7th or 8th intercostal space along the posterior axillary line on the surgical side, and the thoracic cavity is closed layer by layer.