RU2362517C2 - Portable spine - Google Patents

Abstract

FIELD: medicine; traumatology and orthopaedics.

SUBSTANCE: portable spine comprises a hollow body with a toothed end faces, and console-shaped ledges with ribbed end surfaces at the top and bottom. In end faces on the lateral surface on one side of the device, there are regulators provided. Each regulator is holed for screwing to be convergent on the opposite side and arranged at the different distance from a contactor plate of the spine body wherein they are inserted.

EFFECT: absolute fixation stability of the damaged spinal segments, optimal conditions for rapid bone block formation.

1 ex, 4 dwg

Description

The invention relates to medicine, namely to traumatology and orthopedics, and can be used for the surgical treatment of injuries and diseases of the spine.

A device for repairing a defect resulting from a resection of the body and adjacent discs of the thoracic or lumbar spine, which is a mesh cylinder filled with bone tissue for fusion of vertebral bodies (Akamaru T., Kawahara N., Sakamoto J., et al. The transmission of stress to grafted bone inside a titanium mesh cage used in anterior column reconstruction after total spondylectomy: a finite-element analysis // Spine. 2005; 15 (24): 2783-2787). The disadvantage of this device is that the end surfaces of the mesh cylinder do not create a sufficient support area for stable fixation of segments of the spine.

The closest device to the claimed invention is a spine retainer, which is a hollow body with teeth along the ends. The upper and lower parts of the latch have cantilevered protrusions provided with teeth. On the under-console surfaces of the protrusions, notches are made. For ease of installation, the retainer body has oval openings made with a bevel inside the hollow body (Patent RU 2200511, MPK7 A61F 2/44). The latch provides reliable fixation of the vertebrae with the replacement of the damaged vertebral body and complete correction of post-traumatic deformity. However, it does not create conditions for complete stability of fixation, since it does not prevent extensional mobility in the fixed segment.

The objective of the invention is to provide a retainer of the spine, preventing extensional mobility in the damaged segment and providing complete stability of the fixed segments of the spine for the rapid formation of bone block.

The technical result of using the proposed spinal fixator is to prevent extensional mobility in the fixed segment and to increase flexion and rotational stability in it, which contributes to the rapid formation of bone block, and also allows patients to become active after severe spinal injuries without external immobilization and in the early stages after surgery.

The problem is solved due to the fact that the spine retainer, containing a hollow body with teeth at the ends and cantilevered protrusions with a notch on the end surfaces in its upper and lower parts, is additionally equipped with stabilizers located in the end parts along the side surface of one side of the fixator, each stabilizer has holes for holding screws with the possibility of convergence on the opposite side of the introduction and location at different distances from the end plate of the vertebral body, in which they are introduced.

The technical result is achieved due to the combination of design features of the spinal retainer, which allows to completely eliminate both the rotational and flexion and extensional mobility of the damaged segments of the spine. The teeth along the end surfaces and on the cantilever ledges provide rotational and flexion stability, and the stabilizers and screws drawn through them, and the relative position of these screws in the vertebral bodies provide extensional stability and increase the resistance to flexion and rotational loads.

Figure 1 shows a General view of the retainer of the spine.

Figure 2 illustrates the relative position of the screws after their introduction into the holes of the stabilizer.

As can be seen in figure 1, the spine retainer consists of a hollow body 1 with teeth 2 at the ends. On the sides of the hollow body 1 there are ellipsoidal openings 8. In the upper and lower parts of the retainer body 1, on the opposite side of the radial wall, there are cantilevered protrusions 3, the end surfaces of which are provided with teeth 4. On the one side of both end parts of the retainer, stabilizers 5 are made with holes 6 for holding screws 7 (Figure 2) in each of them.

The stabilizers 5 bottom and top go into the wall thickness of the hollow body of the latch 1, have a curvature corresponding to its curvature, and are located anterior to the cantilevered protrusions 3 (Figure 1). The round holes 6 in the stabilizers 5 are located at different distances both from the end surface and from the back (the beginning of the cantilevered protrusions) of the hollow body of the retainer (Fig 1). Vertical planes passing through the axis of the holes converge within the vertebral body into which the screws are inserted, while horizontal planes passing through the same axes do not intersect within the vertebral body.

The shape of the stabilizers 5 and the location of the holes 6 in them provide both the convergence (Figure 2) of the screws 7 on the opposite side of their insertion, and their position at different distances from the vertebral contact plates into which they are inserted. A bone autograft is introduced into the hollow body 1 of the fixative, which subsequently forms the bone block of the vertebrae.

The installation of the latch is as follows.

Surgical intervention is performed under general endotracheal anesthesia. The level of spinal damage is localized. Through the transthoracic access in case of damage to the thoracic and upper lumbar vertebrae and through the left-side extraperitoneal access in case of damage to the lower lumbar vertebrae, the damaged vertebra is exposed together with the caudal and cranial parts of the adjacent vertebrae. Over the body of a broken vertebra, damaged disks and adjacent parts of adjacent vertebrae, the revertebral fascia is dissected. The anterolateral surface of the broken vertebral body and damaged discs is exposed, and at the level of the broken vertebra, the anterior longitudinal ligament with some of the bone fragments of the anterior cortical plate is exfoliated. If necessary, the anterior longitudinal ligament is excised together with adjacent intervertebral discs, preserving only the posterior portions of the fibrous rings. The spine is given an extension position and correction of spinal deformity is achieved. Hyaline plates of intact adjacent vertebral bodies are removed. The ventral part of the broken vertebral body is resected according to the size of the hollow part of the fixative, and the ventral height of the defect formed corresponds to the dimensions of the anterior part of the fixative. In the end plates of adjacent intact vertebral bodies in the strictly frontal plane, grooves are formed for the entire transverse size of the body using a double-edged osteotome or "test template". The depth of the grooves is 3 mm. The distance from the front edge of the limb to the grooves in the intact vertebrae corresponds to the distance from the front edge of the upper or lower parts of the retainer to the posterior teeth on its cantilevered protrusions. Thus, the bed is prepared for the latch. It is firmly held by a gripping device, the branches of which are inserted into one of the technological holes on its side surface. A retainer with a bone graft located in it is inserted into the formed bed in the frontal plane. In this case, the optimal location of the latch is provided by the advancement of the rear teeth on the cantilever ledges along the grooves formed in the locking plates. After the retainer is completely immersed in the bed, the stabilizers fit snugly against the lateral surfaces of adjacent vertebral bodies. Spine extension is eliminated and the gripping device is removed. The front part of the retainer completely replaces the formed defects of the interbody spaces and the resected part of the broken vertebra. When installing the clamp, the stabilizers are adjacent to adjacent vertebrae in a safe area where there are no spinal roots and main vessels. Screws are screwed into the bodies of adjacent vertebrae through openings in the stabilizers, located closer to the closure plates and parallel to them, through transversely formed channels. Through holes in the stabilizers, located further from the end plates, channels are formed and screws are inserted so that the latter converge with the previously inserted screws on the opposite side of the insertion. In this case, the screws can perforate the cortical plate of the vertebrae, not only on the side of the insertion, but also on the opposite side. The operation ends with wound closure.

Thus, as a result of the fixation, the height of the interbody spaces is restored due to the introduction of cantilevered protrusions into the locking plates, while the posterior portions of the fibrous rings are stretched, displacing the dorsal fragments of the broken body in height, and the straining posterior longitudinal ligament contributes to their forward displacement. With extension of the spine, the tensile stress of the fibrous rings and the posterior longitudinal ligament is enhanced. The cantilever parts, located in the interbody spaces between the dorsal parts of the resected and intact vertebral body, provide an increase in the area of the support, the degree of fixation of the vertebrae and the fixator itself. Stabilizers and introduced screws provide extensional stability and increase resistance to flexion and rotational loads. The latch is firmly held in the bed, reliably fixes the vertebrae and preserves the full correction of the spinal deformity, providing favorable conditions for the formation of the bone block. The latch is easy to use, and its use does not expand the scope of the operation.

From the first days after surgery, the patient is prescribed exercise therapy and active bed rest. On day 3-5, when the pain syndrome in the area of the postoperative wound decreases, patients walk freely. In the postoperative period, there is no need for immobilization with a plaster cast.

An example of the clinical use of a spinal fixative.

Patient Sh., Born in 1958, was admitted to the Clinic for Uncomplicated Spinal Injury of the Novosibirsk Scientific Research Institute of Pediatric Surgery on January 9, 2007. After a comprehensive clinical and radiological examination, MSCT made a clinical diagnosis: Closed, uncomplicated comminuted fracture with frontal splitting of the vertebral body L2 (A2.2.2 according to AO / ASIF classification) (Figure 3). On January 23, 2007, an operation was performed on ventral bisegmental corrective spinal fusion of L1-L3 vertebrae using a spine fixator and bone autografts.

Left-sided access, thoraco-lumbar. In the course of the IX rib on the left with the transition to the anterior abdominal wall, the skin, subcutaneous tissue, muscles of the chest and abdominal walls are dissected, the corresponding rib is subperiostally and resected within the wound. Crossed costal arch. The left pleural cavity is opened. Easy is free. The peritoneal sac is peeled and laid up and to the right. The bone diaphragmatic sinus and diaphragm were cut for 10 cm. Paravertebral tissues over the bodies of the L1-L3 vertebrae were bluntly stratified. Bandaged segmental vessels at the level of L2 vertebra. It was revealed that the body L2 is destroyed by the entire vertical size, wedge-shaped, the disks L1-L2, L2-L3 are sharply narrowed, the surrounding tissues are imbibed with blood. The vertebral body L2 is resected to its entire vertical size along with adjacent adjacent discs and hyaline plates of adjacent vertebrae. Anterior longitudinal ligament saved. It is detached and medially displaced. Extension was given at the operating level by the roller of the operating table, feasible traction along the ventral sections with a distracting instrument was performed, kyphosis was corrected, the height of the vertebral segment was restored. Grooves are formed at the border of the middle and posterior third of the caudal part of L1 and the cranial part of L3 of the vertebrae with a bit in the lateral-lateral direction. In the defect, in accordance with its dimensions, a fixer with bone autografts from the resected rib inside is inserted so that the cantilever protrusions of the fixator are installed in the formed grooves. After eliminating the extension, the fixer jammed between the bodies of L1 and L3 vertebrae. The retainer stabilizers fit snugly against the outer surfaces of the vertebral bodies L1 and L3. Through the holes of the stabilizers in the body L1 and L3 of the vertebrae introduced two pairs of screws. The screws in each pair are introduced with convergence at different distances from the vertebral end plates. Restored diaphragm integrity. Installed drainage into the retroperitoneal space, the pleural cavity is drained through the X intercostal space. The wound is sutured in layers. Intraoperative blood loss was 400 ml.

The postoperative period was uneventful. On the 6th day, the patient was raised to a vertical position in a removable orthopedic corset. On the control x-ray after 4 months, the achieved correction is saved, there are signs of the formation of the ventral bone block L1-L3 of the vertebrae (figure 4).

Claims (1)

A spinal retainer containing a hollow body with teeth at the ends and cantilever protrusions with a notch on the end surfaces in its upper and lower parts, characterized in that stabilizers are made in the end parts along the lateral surface of one side of the fixator, each stabilizer has holes for holding screws with the possibility of their convergence on the opposite side of the introduction and location at different distances from the end plate of the vertebral body into which they are inserted.

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