RU2798042C1 - Method of spinal cord decompression in case of fractures of the thoracic and lumbar vertebrae - Google Patents

Abstract

FIELD: medicine, traumatology, orthopedics and neurosurgery.

SUBSTANCE: invention can be used for anterior decompression of the spinal cord in fractures of the thoracic and lumbar vertebrae. After the installation of the transpedicular device on the spine, distraction and reclination of the damaged segment of the spine is performed. Under image intensifier control, a transforaminal access to the intervertebral disc of the damaged vertebra is performed and the lower articular process of the overlying vertebra and the upper articular process of the underlying vertebra are resected. The fibrous ring is opened and a discectomy is performed, then a medical steel instrument containing a handle whose plane coincides with the plane of the working part of the instrument and a connecting rod, from the distal end of which the working part of the instrument departs at an angle of 100 degrees, is inserted into the spinal canal under the dura mater, it is brought in turn to each free bone fragment, advanced into the area of the removed disc and pressed into the vertebral body. Spinal fusion is performed with an autologous bone from the resected vertebral joints. Finally, a metered compression is performed with a transpedicular device to pinch bone fragments in the cortical layer of the anterior wall of the spinal canal, the pedicle screws are fixed in the achieved position, and the pedicle device is dismantled.

EFFECT: method provides complete decompression of the spinal canal without damage to blood vessels, roots and dura mater due to preliminary discectomy, advancement of bone fragments into the area of the removed disc and subsequent interbody fusion of the damaged spinal segment.

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Description

SUBSTANCE: invention relates to medicine, namely to traumatology, orthopedics and neurosurgery, and can be used after unremoved anterior compression of the contents of the spinal canal using a transpedicular repositioning device for fractures of the thoracic and lumbar vertebrae. The surgical treatment of such patients is based on the implementation of neurosurgical and orthopedic approaches.

Fractures of the thoracic and lumbar vertebrae are often accompanied by anterior compression of both the spinal cord and the roots of the spinal cord by bone fragments when they are displaced towards the spinal canal. If the posterior longitudinal ligament is damaged, it is not possible to eliminate the central compression due to ligamentotaxis (tension of the posterior longitudinal ligament). Decompressive surgical interventions on the anterior structures of the spine are more traumatic and time-consuming, require special training, and can also lead to various severe complications. Most methods of anterior decompression of the contents of the spinal canal from the posterior approach after decompressive laminectomy (removal of the vertebral arch) with the removal of bone fragments are quite traumatic and do not always lead to the desired results.

A known method of anterior decompression of the spinal cord after laminectomy (RF patent 2306887 A61V 17/56, 2004), which includes resection of the root of the vertebral arch, resection of the articular processes and the lateral wall of the spinal canal, the formation of a canal in the posterior part of the body of the damaged vertebra using a crown cutter, wedging fragments located intracanally in the ventral direction into the formed defect.

The disadvantage of this method is the need to remove all the posterior bone formations of the vertebra during decompression, when performing anterior decompression, a large volume of the body of the damaged vertebra is removed, and removal of fragments requires abduction of the spinal cord.

Another method of spinal cord decompression in case of fractures of the thoracic and lumbar vertebrae (RF patent 2467716, A61V 17/56, 2011) includes resection of the vertebral arch root, resection of the articular processes and the lateral wall of the spinal canal, formation of a channel in the posterior part of the body of the damaged vertebra using a crown cutter , as well as resection of the root of the arch closest to the fragment of the vertebra, removal of the posterior third of the body of the fractured vertebra within the middle supporting column of the spine with preservation of the anterior wall of the spinal canal, displacement of the preserved anterior wall of the spinal canal and bone fragment into the area of resection of the posterior third of the vertebral body, followed by removal of the fragment under endoscopic control.

With this method, the resection of the posterior bone structures of the spine is reduced. Removal of fragments that compress the spinal cord occurs under video endoscopic control without traction (stretching) of the spinal cord. Disadvantages: when forming a channel for access to the body of a broken vertebra through the pedicle of the arch, a cutter with a diameter of 10-12 mm is used. Considering the anatomical dimensions of the pedicle of the arc in the thoracic region, when a cutter of this diameter passes, it is possible to displace both the drill itself and the bone fragments of the anterior wall of the spinal canal and, as a result, damage to the nerve root that goes around the pedicle of the arc, and radicular vessels. Given the blood supply to the vertebral body, the use of video endoscopic control is hampered by bleeding. It is difficult to carry out corporodesis.

A known method of anterior transpedicular fusion (RF patent 2331378, A61V 17/56, 2007). The method includes anterior decompression of the spinal cord, reclination (straightening) of the fractured vertebral body, and anterior spinal fusion (spinal fixation operation). A longitudinal channel is formed in the vertebral body using a cannulated drill introduced into the vertebral body along a guide pin previously inserted into the vertebral body through its pedicle. Reclination is carried out with a rigid reclinator through the formed channel. The bone graft is formed from the spinous processes and arches of the vertebrae as a single block, and the diameter of the drill exceeds the vertical size of the pedicle of the vertebral arch. EFFECT: method ensures performing anterior transpedicular fusion with supportable autografts in the acute period of spinal injury. The method allows the wire to pass through the root of the arch of the damaged vertebra less traumatically.

The disadvantages of the method include its general invasiveness due to the fact that it is necessary to remove all the posterior bone-ligamentous structures of the vertebra, which increases the operation time and blood loss. It is also difficult to maintain the achieved reclination, since after the removal of the hard reclinator, the segment will subside.

A known method of eliminating anterior compression of the spinal cord (Hardaker WT Jr, Cook WA Jr, Friedman AH, Fitch RD. Bilateral transpedicular decompression and Harrington rod stabilization in the managenet of severe thoracolumbar burst fractures. Spine (Phila Pa 1976). 1992 Feb; 17( 2): 162-71 doi: 10.1097/00007632-199202000-00008. PMID: 1553587), when intracanal bone and cartilage fragments were removed with special punchers through the formed canals in the roots of the arches of the damaged vertebra, and the operation was completed by osteosynthesis of the spine from the posterior approach without performing laminectomy.

This method is less traumatic, allows you to save the posterior supporting structures of the vertebra. The disadvantages of this decompression method include the lack of visual control of the instruments, the use of special complex instruments and equipment for this method.

Close to the claimed method of decompression is a method implemented by a device for minimally invasive decompression of the spinal canal (RF patent 161471, A61B 17/56, 2015). The technical result is achieved due to the fact that the device, containing the impact and working parts, is equipped with a figured handle with rounded edges, which is smoothly connected to the working part of the device with a diameter of 15 mm. The shock part of the device is made in the form of an anvil with a diameter of 50 mm, and the end of the working part of the device 20 mm long is bent at an angle of 100 degrees to the axis of the device and bevelled. Transforaminal or translaminar access to the damaged segment is used. Then, the canal is inspected through the window, yellow ligaments are removed, the lateral membrane is dissected, and compressing bone fragments are searched using the proposed device as a palpator probe. The found compressing fragment is correlated to the level of the height of the vertebral body. Using a cutter, a hole is formed in the body of a broken vertebra anterior to the compressing fragment. Then the proposed device is installed on the top of the bone fragments, that is, in the narrowest place of the canal, and the fragments fall into the previously formed hole in the vertebral body. If necessary, for punching fragments, the device is subjected to impact loads with a hammer on the anvil.

The disadvantages of decompression using this device include the very dimensions of the proposed device (15-20 mm working part). When decompressing, especially in the thoracic region, the proposed device is difficult to bring into the foramen. When looking for compressing fragments along the vertebral body (the fragment is located at the root of the arch), the working part of the instrument enters the spinal canal, which leads to displacement of the spinal cord. Therefore, to reduce the traction of the spinal cord, it is necessary to expand the access. It is not explained how holes are formed in the body of a broken vertebra with a cutter (the direction of the hole, its diameter).

The prototype for the method for decompressing the contents of the spinal canal in the thoracic and lumbar regions after a spinal cord injury is a method implemented using a device for impregnating bone fragments (RF patent 2568769, A61B 17/56, 2014).

At the level of damage, performs laminectomy or hemilaminectomy, depending on the degree of spinal canal stenosis and the severity of neurological disorders. Perform reclination on the operating table. A transpedicular structure is mounted and the spine is distracted. The spatula of the device for impregnation of bone fragments is inserted epidurally into the spinal canal, the device is fixed on the rod of the transpedicular design at the site of the proposed impregnation of bone fragments. Before the start of impregnation with an injection needle, an adhesive composition Tissucol Kit with a slow gluing effect is injected into the body of a broken vertebra. By rotating the control wheel, the spatula of the rod is lowered, exerting dosed pressure on the protruding bone fragments, and they are pressed into the body of the broken vertebra. After achieving the desired result, while keeping the device in working order, an adhesive composition with a fast gluing effect is injected into the space between the anterior and posterior walls of the body of the broken vertebra through the holes in the surface of the spatula using a needle.

With the help of this device, dosed impregnation of bone fragments for decompression of the spinal canal occurs, and adhesive compositions prevent the secondary migration of bone fragments.

The disadvantages of the known method include the complexity of the device used and the danger of violating the integrity of the posterior bone-ligamentous structures of the vertebra. In addition, no control is provided for the volume of injected adhesive compositions that determine the duration of the operation.

The objective of the claimed invention is to develop a method for decompressing the spinal cord, in which the elimination of post-traumatic stenosis of the spinal canal could be carried out without complications associated with damage to blood vessels, spinal roots and dura mater, as quickly as possible and with high quality decompression.

The problem was solved in the following way.

Considering that in most cases bone fragments remain fixed to the fibrous ring of the intervertebral disc on one side, and the second free end of the fragment in the form of a “key” protrudes into the spinal canal, under the conditions of instrumental transpedicular reposition of the vertebra, bone fragments can be returned to their place with special tools after creation. spare space from a previously performed discectomy.

According to the claimed solution, after the transpedicular device is installed on the spine, additional distraction and reclination of the damaged segment of the spine is performed, under image intensifier control, transforaminal access to the intervertebral disc near the damaged vertebra is performed and the nearest articular processes of neighboring vertebrae are resected, the annulus fibrosus is opened and discectomy is performed. Next, a special instrument is inserted into the spinal canal, it is brought in turn to each free bone fragment and advanced into the area of the removed disk, after which spinal fusion is performed with an autobone from the resected vertebral joints. Finally, a slight compression is performed with a transpedicular device and the bone fragments are infringed in the cortical layer of the anterior wall of the spinal canal.

The technical result of the proposed method consists in the fact that the performance under the image intensifier tube control of preliminary discectomy creates a reserve space for immersion of bone fragments, frees up space for interbody fusion with crushed autologous bone and thereby allows for complete decompression of the spinal canal without laminectomy and damage to blood vessels, spinal roots and hard tissue. meninges, and also avoids surgical intervention with an anterior approach.

The invention is illustrated by the following diagrams:

Fig. 1. Instrument for minimally invasive decompression of the spinal canal, front view.

Fig. 2. Tool for minimally invasive decompression of the spinal canal, side view.

Fig. 3. Tool for minimally invasive decompression of the spinal canal, top view.

Fig. 4. Tool for minimally invasive decompression of the spinal canal, photo.

Fig. Fig. 5. Persistent compression of the dural sac with a free bone fragment under conditions of the use of a transpedicular repositioning system.

Fig. 6. Scheme of transforaminal access, discectomy.

Fig. Fig. 7. Stage of immersion of bone fragments, side view.

Fig. Fig. 8. Stage of immersion of bone fragments, top view.

To implement the proposed method of spinal cord decompression, special tools have been developed. These instruments are made of medical steel alloy and have a flat handle (1) with dimensions of 7-20-100 mm. The plane of the handle (1) coincides with the plane of the working part of the instrument, which allows you to control the working part of the instrument when it is in the spinal canal. The handle smoothly passes into the connecting rod (2) from a diameter of 7 mm to a diameter of 2 mm and a length of 200 mm, this length of the connecting rod allows you to work with instruments on the repositioning system. From the distal end of the connecting rod at an angle of 100 degrees (this angle contributes to a convenient location of the instrument in the wound during the depression of bone fragments), the working part of the instruments (3) is 18 mm long, 3 mm wide and 1.5 mm thick, which is curved along a plane with with a radius of 20 mm to the left and right sides. Thanks to these bends of the instruments, it becomes possible to enter the spinal canal simultaneously from foraminal accesses in the thoracic and lumbar regions, to press bone fragments without advancing the connecting rod towards the spinal canal, and to reduce trauma to the neurovascular formations of the spinal canal.

The method of decompression is carried out as follows: in case of unresolved anterior compression of the dura mater under the conditions of the superimposed transpedicular repositioning system (4), at the first stage, additional distraction of the damaged spinal motion segment by 1-2 mm is performed (5). Under image intensifier control, one- or two-sided transforaminal access to the intervertebral disc (6) near the damaged vertebra is performed. The lower articular process of the overlying vertebra (7) and the upper articular process of the underlying vertebra (8) are resected to the root of the arch, exposing the lateral wall of the spinal canal. Using an image intensifier tube, the spinal roots (9) are visualized through the transforaminal windows, the yellow ligaments (10) are removed, and the anterior-lateral wall of the spinal canal is revised with a special instrument.

The introduction of the working part of the instruments into the spinal canal after partially performed hardware decompression does not lead to additional compression of the neural structures. The use of an operating microscope makes it possible to avoid complications associated with damage to blood vessels, the spinal root, and the dura mater, and at the same time improve the quality of decompression.

The fibrous ring (11) is exposed and opened within the roots of the arches while protecting the neurovascular formations of the spinal canal. A discectomy is performed (12). With a narrow interbody gap, access can be expanded with a cutter. It is possible to exclude additional displacement of bone fragments during discectomy by inserting this instrument through transforaminal access from the opposite side. Free bone fragments (13) in the projection of the spinal canal remain fixed to the fibrous ring. After discectomy, a reserve space is formed for immersed bone fragments (14). With bilateral access, the proposed instrument is inserted into the spinal canal from the side of the annulus fibrosus and, by bending around the roots of the arches of the damaged vertebra (15), is brought to the free bone fragment (13). When the instrument is advanced in the spinal canal, the fragment is simultaneously immersed in the ventral direction (16). Additional distraction of the damaged segment of the spine facilitates the displacement of bone fragments in the ventral direction, and discectomy facilitates their turn towards the removed disc. The tool, due to the bending of the working part, advances the bone fragments adjacent to the roots of the arches, without displacement of the lateral wall of the dura mater and without injuring the outgoing nerve root. Through defects in the fibrous ring, spinal fusion is performed with autologous bone from the resected joints of the vertebrae or with osteoinductive material. During spinal fusion, special instruments allow you to control the displacement of bone fragments.

After restoration of the anterior wall of the spinal canal and spinal fusion, to prevent re-displacement of the depressed bone fragments, compression by a repositioning system by 1-2 mm (17) is performed and these bone fragments are incarcerated in the cortical layer of the anterior wall of the spinal canal. The faster the surgical intervention is performed from the moment of injury, the technically easier and easier it is to carry out. Transpedicular screws in this position are rigidly fixed with rods, the repositioning system is dismantled. The operation ends with drainage and suturing of the postoperative wound.

The proposed method of decompression and tools used by us in the clinic in the treatment of patients with spinal injuries in the thoracic and lumbar regions (from ThX to LIV).

Clinical example: Big M., 32 years old, was admitted for treatment in the neurosurgical department after an accident with a diagnosis of Comminuted fracture of the LII vertebral body (type A3 according to the AO classification) with contusion and compression of the epiconus of the spinal cord. lower paraparesis. According to the CT data, it was found that 2 bone fragments up to 8.5 mm were displaced into the spinal canal. Moreover, the fragments conventionally have a triangular shape and were formed as a result of immersion of the upper vertical plate of the body of the LII vertebra with simultaneous displacement of the broken part of the posterior wall of the vertebra during rupture of the posterior longitudinal ligament. After preoperative preparation, the patient was taken for surgery. Anesthesia - endotracheal anesthesia.

With EPO marking, deformation of the anterior wall of the spinal canal is noted. Posterior median approach with exposure of the joints for insertion of pedicle screws into the bodies of LI, LII, LIII vertebrae. After the screws were inserted, a transpedicular repositioning system was mounted, distraction and reclination of the damaged spinal segment was performed. In the control image intensifier study, there is a decrease in the deformation of the anterior wall of the spinal canal by more than 1/3. The repositioning system additionally performed distraction of the LI-LII segment by 2 mm. Under image intensifier tube control, bilateral transforaminal access to the LI-LII disc was performed with resection of the superior articular processes of the LII and inferior articular processes of the LI vertebra, exposing the lateral wall of the spinal canal. The yellow ligaments were removed under a microscope, the spinal roots were visualized, and the spinal canal was revised using special instruments. Found bone fragments, and one edge of which is fixed to the fibrous ring. There were no signs of damage to the dura mater. The dura mater and roots are protected with radicular spatulas, the fibrous ring within the roots of the arches is isolated and opened on both sides. Discectomy was performed using microinstrumentation. To prevent the migration of bone fragments during discectomy, special instruments were inserted into the spinal canal from the opposite side to immerse the bone fragments. After the discectomy performed on both sides, the bone fragments were immersed in the central direction with their turn towards the removed disc. Image intensifier control; bone fragments were crushed and used for corporodesis. Performed compression repositioning system 2 mm and infringement of displaced bone fragments in the cortical layer of the anterior wall of the spinal canal. Control of the position of fragments with the help of instruments and on the image intensifier tube. Transpedicular screws in this position are rigidly fixed with rods, the repositioning system is dismantled. Made drainage and layer-by-layer suturing of the wound.

The wound healed by first intention. The sutures were removed on the 10th day. In the early postoperative period, the patient is vertical. Neurological status: positive dynamics. The patient was discharged on the 12th day for outpatient treatment.

Claims (1)

A method for anterior decompression of the spinal cord in fractures of the thoracic and lumbar vertebrae, including reposition of the damaged spine with a transpedicular device, access to the spinal canal and wedging of free bone fragments into the vertebral body, characterized in that after the installation of the transpedicular device on the spine, distraction and reclination of the damaged segment of the spine are performed , then, under image intensifier control, transforaminal access is made to the intervertebral disc closest to the damaged part of the injured vertebra, and the lower articular process of the overlying vertebra and the upper articular process of the underlying vertebra are resected, then the annulus fibrosus is opened and discectomy is performed, then a medical steel instrument containing the handle, the plane of which coincides with the plane of the working part of the instrument, and the connecting rod, from the distal end of which the working part of the instrument departs at an angle of 100 degrees, is inserted into the spinal canal under the dura mater, brought in turn to each free bone fragment, advanced into the zone removed disc and pressed into the vertebral body, after which spinal fusion is performed with an autologous bone from the resected joints of the vertebrae; transpedicular device.

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