EA030844B1 - Method for restoration of broken vertebra - Google Patents

Abstract

The invention relates to the field of medicine, particularly traumatology, orthopaedy, and neurosurgery, and to methods for broken vertebrae treatment. In convenient methods, height of restored broken vertebra depends on volume of a cavity formed by surgeon in fracture site, as well as on nature of bone-replacing material being inserted into the cavity (see RF Patent 2351375 IPC A16V 17/56 publ. in 2009; RF Patent 2411017 publ. on 10.02.2011). Disadvantages of the above methods are loss of restored vertebra height, control on cavity formation, need in ultrasound vibration, and large injury during operation. Task of the invention consists in increasing surgery efficiency due to accurate formation of cavity in a vertebra, and subsequent filling it with titanium nickelide granules, which have osteogenesis stimulating properties, and also in decreasing morbidity. The result is achieved by the method for restoration of broken vertebra, comprising distraction, transpedicular reposition, filling of cavity with titanium nickelide granules; the method being remarkable in that formation of cavity is made using an anchor screw of adjusted diameter, by its reciprocal motion at 15 to 20 mm from blind end of the channel. After working-out of cavity, diameter of the anchor screw is reduced to initial size by unscrewing the rod, thus allowing removal the screw from cavity through the channel.

Description

The invention relates to the field of medicine, namely, traumatology, orthopedics, neurosurgery, to methods for treating a broken vertebra. The height of the restored broken vertebra in known methods depends on the volume of the cavity formed by the surgeon in the fracture region, as well as the quality of bone replacement material introduced into the cavity (RF Patent 2351375 IPC AV 17/56, published 2009, RF Patent 2411017, publ 10.02. 2011). The disadvantages of these methods are the loss of the restored height of the vertebra, the level of control of the formation of the cavity, the need for ultrasonic vibrations, high invasiveness. The technical objective of this invention is to increase the efficiency of the operation due to the exact formation of the required volume of the vertebral cavity, followed by filling it with granules of titanium nickelide with osteogenesis stimulation properties, reducing trauma. The technical result is achieved due to the fact that in the method of restoring a broken vertebra, including distraction, transpedicular reposition, filling the cavity with titanium nickelide granules, characterized in that the formation of the cavity is performed with an anchor screw with an adjustable diameter, reciprocating movements in the area of 15-20 mm from the dead end of the channel. After the cavity has been developed, the diameter of the anchor screw is brought back to the original by unscrewing the pusher from it, which allows the screw to be withdrawn from the cavity through the channel.

The invention relates to the field of medicine, namely to traumatology, orthopedics, neurosurgery, to methods of treatment (recovery, plastics) of a broken vertebra.

A common type of traumatic injury to the spine is a compression fracture of the vertebral body, leading to disintegration of the vertebral body with a decrease in its height.

The restoration of height in the known methods is carried out by forming a cavity in the region of the fracture of the vertebral body, which is filled with bone-replacement material. The restored height directly depends on the volume of the cavity formed and the properties of the material introduced. For the formation of the cavity using various devices: inflatable spray, special technical devices. To enter them in the body of the vertebra pre-form channels.

Restoration of the shape and height of the vertebra is complicated by the influence of muscle tone, elastic-elastic properties of the body of the affected vertebra, and compression by adjacent intact vertebrae.

The known method of vertebroplasty [Mueller ME, Algauver M., Schneider R., Willingegter X. Guide to internal osteosynthesis. Publisher Springer - Verlag, Moscow, 1996]. Bone shavings are used as material for transpedicular canals. The disadvantage of chips is a tendency to resorption, which leads subsequently to a decrease in the adhesion forces of the bone fragments.

A known method for the treatment of vertebral body fractures (Patent RF 2351375, IPC AV 17/56, published 2009), including the introduction into the body of the damaged vertebra of the balloon and the recovery of the height of the vertebral body by inflating it in the direction of the compression area of the damaged vertebral body. After the balloon has been blown off and removed, the cavity formed is filled with bone-replacement material, which is sealed by contact with ultrasonic vibrations.

The disadvantage of this method is the partial loss of the restored height of the vertebra after removing the balloon, as well as its complexity in execution, the use of ultrasonic vibrations lengthens the operation time, high invasiveness.

The closest to the claimed invention in essence and the achieved technical result is the method of plastics of the body of a broken vertebra (Patent RF № 2411017, publ. 10.02.2011). To restore the damaged vertebra, the following manipulations are performed. For unloading the damaged vertebra 1 (Fig. 1), the adjacent vertebrae 2 are fixed (distraction of the vertebra) using a pedicle clamp consisting of screws 3 fixed on the rod 4. Transverse of the fracture surfaces of the vertebral body with the approach from the roots of the arches are performed deaf transpedicular channels 1 Fig. 2) with a diameter of 5 mm and a depth of 25 mm using scoring and crown cutters. Through the funnel 3, the channels are filled with granules of permeable porous titanium nickelide with transverse sizes of granules in the range of 0.5–5.0. Filling is performed sequentially, starting from the distal (blind) end of the channel to its mouth, compaction of each portion by manual efforts with the help of tamping rods 4 with light blows of a hammer. At fault section 2, tamping forces increase in terms of the subjective sensations and shrinkage response of the volume of the pellets introduced into the fracture gap. The mouths of the canals are plugged with a hemostatic sponge.

The disadvantage of the method is due to the fact that the restoration of the shape and height of the damaged vertebra occurs mainly due to its expansion by filling the fracture site with bone replacement material (titanium picelide), carried out by tamping efforts, the amount of which is difficult to quantify and control for a more rigorous justification of the filling modes. In case of excessive efforts, there are risks of damage to the cortical layer of the spinal body, displacement of fragments into the spinal canal. The expansion of the vertebral body, which occurs due to the formation of a deaf transpedicular canal, is insignificant and is determined by the diameter of the cutter (screw).

This analogue with the proposed solution is selected as a prototype.

The technical task of the invention is to improve the efficiency of the operation due to the controlled formation of the cavity for filling bone material of the damaged vertebra, eliminating the risks of disruption of the cortical layer and displacement of fragments into the spinal canal.

The technical result is achieved due to the fact that in the method of restoring a broken vertebra, including distraction, reposition, fastening of vertebral fragments by creating transpedicular deaf canals, filling them with permeable porous nickelide titanium, forming (developing) the cavity for the material is done by inserting the anchor screw all the way into a stupid canal with a further screwing of the screw and reciprocating movements to areas of 15-20 mm from the blind end of the channel.

The anchor screw consists of a head 1, a screw part 2 and a pusher 3 (Fig. 3). The body of the screw along the length of the screw part has longitudinal slits 4. The pusher is screwed along the internal thread of the screw 5; as a result, the bulge occurs and the diameter of the screw in the end part increases. After completion of the development of the cavity, the pusher is unscrewed and the anchor screw, due to the elastic forces of the screw material, acquires the initial diameter, which allows it to be easily removed from the channel.

The formation of the cavity for bone replacement material is as follows.

- 1 030844

The anchor screw with the pusher is in the initial position, as shown in FIG. 3, is screwed all the way into the preformed deaf transpedicular canal 1 (Fig. 2). The key, which is inserted into the nest of the pusher 6 (Fig. 3), is used to screw in the pusher for the required thread length.

As a result of this manipulation, the end part of the anchor screw is spreading, the diameter of which depends on how many turns of the thread the pusher is screwed in, and the maximum diameter is equal to the sum of the original diameters of the screw and the pusher. With an increase in the latter, the overall diameter of the end portion of the screw increases (Fig. 4, 5a).

The development of the cavity for bone replacement material is carried out by reciprocating movements (screwing / unscrewing) of the expanded anchor screw in the area of 15-20 mm from the blind end of the canal in the ventral part of the vertebral body. It is this part of the most vulnerable to injuries and is accompanied by the greatest loss of height of the vertebra. The development of the cavity is accompanied by a noticeable increase in the height of the damaged vertebra. Development can be done in several stages: starting with small diameters of the anchor screw with the transition to large diameters (Fig. 5). FIG. 5a shows the formation of the cavity, and 5b shows the restored height of the vertebra, the anchor screw, ready to be removed from the vertebral body through the transpedicular canal.

This process and the operation as a whole are visually monitored by the surgeon with the help of 3E images of an intraoperative computer tomograph (O-arm). After the cavity has been formed, the pusher is unscrewed to its original position, and the screw, acquiring its original diameter, is removed through the transpedicular canal. As a result, we obtain a flask-shaped (Fig. 6a, b) cavity, the body of which is formed using an extended anchor screw, and the neck is due to the transpedicular canal. At the same time, the bottom part of the bulb falls on the ventral part of the vertebral body, which, as a rule, is exposed to the greatest destruction. A bone-replaceable material in the form of titanium nickelide granules is introduced into the finished cavity and does not require additional mechanical efforts to compact it.

The salient feature of the invention is the ability to control the diameter of the anchor screw due to the screw-in depth of the pusher into the screw, which allows controlling the formation of the cavity diameter for bone replacement material.

Another significant feature is that, according to the proposed method, the pellet of bone-replacing material is introduced into the finished cavity, which eliminates the process of mechanical tamping of the material.

In the aggregate, this allows minimizing the risks of disturbing the cortical layer of the injured vertebra, displacement of fragments into the spinal canal, thereby increasing the consistency and effectiveness of the proposed method.

Achievability of the technical result is determined mainly by its simplicity in execution, which does not require complex balloon kyphoplasty devices, special devices for cavity expansion under bone replacement material, and ultrasound.

Achievability of the technical result is confirmed by clinical examples of the treatment of patients with vertebral fractures.

Example 1

Patient A. 47 years old Diagnosis: Closed compression unstable uncomplicated fracture of the bodies of Th ₁₁ -Th ₁₂ vertebrae (A 1.2, AO). Condition after WTP Th ₁₁ -Th ₁₂ -L ₁ vertebrae by the Stryker system, plastics of the body of the Th ₁₂ vertebra with granules of porous TiNi on the left (02/25/2015.

Axial images taken before the operation, during and after the operation with the O-arm are shown in FIG. 7-10.

FIG. 7 shows a snapshot of a damaged vertebra taken before the operation.

In the snapshot of FIG. 8 shows a cavity 1 in the body of a vertebra, obtained by means of an anchor screw.

FIG. 9 shows a cavity 1 in the body of a vertebra, filled with granules of porous titanium nickelide.

FIG. 10 shows the pictures taken after the operation. Vertebra 1 is restored by creating cavity 2 using an anchor screw, then filled with titanium nickelide granules.

Example 2

Patient D., 18 years old. Diagnosis: Closed unstable, uncomplicated compression fracture of the body of the L ₁ vertebra 3 degrees with stenosis of the spinal canal by 1/5; closed unstable, uncomplicated compression fracture of L ₂ vertebrae of 2 degrees; fracture of the spinous process of the Th ₁₂ vertebra. Rupture of axial ligaments L _1-2 vertebrae. Condition after WTP Th ₁₂ -L ₁ -L ₂ vertebrae with the XIA 2 system (Stryker), plastics of the Lj vertebra body with granules of porous TiNi (06/05/2015).

FIG. Figures 11–14 are pre-surgery, post-surgery, and post-operation images.

Claims (4)

CLAIM 1. A method of restoring a broken vertebra, including distraction, reposition, bonding of vertebral fragments by creating transpedicular deaf canals, filling them with biocompatible bone replacement material of permeable porous titanium nickelide, characterized in that the cavity for bone replacement material is formed by inserting an anchor screw to 2. The method according to claim 1, characterized in that the control of the formed volume of the cavity under the bone-substituting material is performed by a gradual increase in the diameter of the anchor screw by screwing the pusher into the anchor screw with the subsequent implementation of reciprocating movements. - 2 030844 emphasis in the deaf transpedicular canal with controlled screwing of the screw due to the screwing in the pusher and further implementation of the reciprocating motion of the screw 15–20 mm from the blind end of the canal. - 3 030844 a b FIG. 6 FIG. 7 FIG. eight FIG. 9 3. The method according to claim 1, characterized in that the biocompatible bone-replacing material, permeable porous titanium nickelide, is introduced into the finished cavity, which eliminates the procedure of its mechanical compaction. FIG. one FIG. 2 FIG. 3 a b FIG. 4 a b FIG. five - 4 030844 FIG. ten FIG. eleven FIG. 12 FIG. 13 FIG. 14