RU2583245C2 - Device for percutaneous transpedicular stabilisation of spinal cord - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to traumatology and neurosurgery, and can be used in treating patients with traumatic and pathological (with underlying osteoporosis and metastatic involvement) fractures of vertebral bodies. Device comprises two first screws and two second screws. First screw is equipped with in-series connected first head with device providing its tight, and first rod with first pointed end. On first rod there is first external thread. First head has second external thread. First screws are made with first through hole made axial. Second screw is equipped with in-series connected second head with device providing its screwing in, and second rod with second pointed end. On second rod there is third external thread. Second screws are made with second through hole made axial. First holes and second holes are filled with cement. Device includes two third screws with spline and fourth outer thread, and two tubes are made reinforced, with nipple on one end. Second holes on side of second head are equipped with first inner thread and provided with groove made open. Tubes are connected by their nipples with first heads by means of appropriate second external threads and second internal threads, partly located in corresponding slots of second heads are fixed in them by appropriate third screws and are filled with cement.

EFFECT: invention provides reduction of operating time required for installation of device.

1 cl, 4 dwg

Description

Technical field

The invention relates to medicine, in particular to traumatology and neurosurgery, and can be used in the treatment of patients with traumatic and pathological (against osteoporosis and metastatic lesions) vertebral fractures.

State of the art

The closest technical solution (prototype) is the method described in the patent of the Russian Federation No. 2285483, publication date 03/27/2005. The invention provides fixation of the spinal-motor segment in the transpedicular screw fixation system in the presence of a pathologically altered vertebral structure with prevention of screw migration due to partial reconstruction of the damaged bone structure. The device according to the first embodiment includes screws of the transpedicular fixation system inserted into the vertebrae, the heads of which are connected by means of locks to the longitudinal rods, and bone cement. Each screw is made with adapted for injection of bone cement, at least one cavity extending on one side to the screw head, and the other through at least one additional channel to the outer surface of the screw shaft. A plug is placed inside the cavity to prevent clogging of the cavity with bone chips, made with the possibility of extraction. The device according to the second embodiment includes screws of the transpedicular fixation system inserted into the vertebrae, the heads of which are connected by means of locks to the longitudinal rods, and bone cement. Each screw is made with adapted for injection of bone cement, at least one cavity made through and facing the pointed end of the screw shaft. A plug is placed inside the cavity to prevent clogging of the cavity with bone chips, made with the possibility of extraction.

The disadvantage of the prototype is significant blood loss during surgery, which significantly reduces the possibility of using these implants in weakened cancer patients with metastases in the vertebral bodies.

The technical result of the invention is to reduce the operating time required for installation of the device.

The technical result is achieved due to the fact that in the device for percutaneous transpedicular stabilization of the spine, containing the first two screws and two second screws, the first screw equipped with a first head connected in series with the means for screwing it in, and a first rod with a first pointed end, on the first shaft is the first external thread, the second external thread is located on the first head, the first screws are made with the first through hole made axial, second the th screw is provided with a second head connected in series with the means for screwing it in, and a second rod with a second pointed end, a third external thread is located on the second rod, the second screws are made with a second through hole made axial, and the first holes and second holes are filled with cement, as well as two third screws with a slot and a fourth external thread, and two tubes made of reinforced with a nipple on one end, the second holes on the side of the second head are provided with the first morning thread and supplemented with a groove made open, the tubes are connected with their nipples to the first heads by means of the corresponding second external threads and second internal threads, partially placed in the corresponding grooves of the second heads, fixed in them by means of the corresponding third screws and filled with cement.

Brief Description of the Drawings

The invention is illustrated by drawings (FIGS. 1, 2, 3, 4), where in FIG. 1 shows a diagram of a device, FIG. 2 shows schematically a first screw; FIG. 3 shows schematically a second screw and a third screw; FIG. 4 shows schematically a tube.

Disclosure of invention

The drawing shows: the body of the vertebra 1, cement 2, the leg of the vertebra 3, the first screw 4, the tube 5, the spinous process 6, the third screw 7, the second screw 8, the first head 9, the second external thread 10, the protrusion 11, the first shaft 12, the first external thread 13, the first hole 14, the first pointed end 15, the slot 16, the fourth external thread 17, the groove 18, the second head 19, the first internal thread 20, the second shaft 21, the third external thread 22, the second hole 23, the second pointed end 24, nipple 25, second internal thread 26, reinforcement 27, free end 28.

The main elements of the device for percutaneous transpedicular stabilization of the spine are the first screw 4, the second screw 8, the third screw 7, a pipe 5 and cement 2 fixed to them.

The first screw 4 consists of a first shaft 12 and a first head 9. A first shaft 12 is attached at its one end to the first head 9, a conical first pointed end 15 is made at the opposite end. On the first head 9 there is a hexagonal protrusion 11 at its base. On the first rod 12, the first external thread 13 is cut along its entire length, and the second external thread 10 is cut on the first head 9. Moreover, a pair of lead cutting edges are made on the first pointed end 15. The cutting edges are ledges inclined to the longitudinal axis of the first screw. The first screw is made with an axial through-hole first hole 14.

The second screw 8 consists of a second shaft 21 and a second head 19. A second shaft 21 is connected at one end to the second head 19, a conical second pointed end 24 is made at the opposite end. A third external thread 22 is cut along its entire length 21, into the second head 19 is cut into a first internal thread 20. The second head 19 has a hexagonal shape. At the same time, in the second head 19, a groove 18 is made on the free end side, the plane of symmetry of which passes through the longitudinal axis of the second screw 8. The groove 18 is a recess in the part, serves to install the adjacent part, in this case it is made rectangular (the definition of the groove is given, for example, in the Big Encyclopedic Polytechnical Dictionary on the website http://dic.academic.ru/dic.nsf/polytechnic/6236/, accessed 07.05.2014). The groove 18 is made open, that is, from one side of the side surface of the second head 19 to the other side of the side surface. In the particular case, the width of the groove 18 may be equal to the outer diameter of the tube 5. At the second pointed end 24, a pair of lead cutting edges are made. The cutting edges are ledges inclined to the longitudinal axis of the first screw. In this case, the second screw is made with an axial through second hole 23.

The third screw 7 does not have a head and is a rod on which the fourth external thread 17 is cut. Moreover, the fourth external thread 17 is configured to screw the third screw 7 into the second head 19 of the second screw 8. In this case, the internal hexagonal slot 16 is made at the end of one of sides of the shaft of the third screw 7.

The device uses a tube 5 made reinforced. At one end of the tube 5, a nipple 25 is fixed. The nipple 25 is a metal connecting tube with a thread for tightly connecting the pipeline to the fitting with a union nut. It is used to connect pipelines, parts of devices, machines, etc. (the definition of the nipple is given, for example, in the Great Soviet Encyclopedia on the website http://dic.academic.ru/dic.nsf/bse/114018/, accessed 04/30/2014), in this case, the nipple 25 and tube 5 can be made made of metal, plastic or other suitable material. A second internal thread 26 is cut in the nipple 25, which makes it possible to screw the nipple 25 onto the first head 9 of the first screw 4. The tube 5 comprises a reinforcement 27 along its entire length.

The implementation of the invention

During the operation, the patient is placed on the operating table on the abdomen and anesthesia is administered. After that, the soft tissues are dissected in a straight line and the vertebral-motor segment to be fixed is exposed. The vertebral-motor segment includes a damaged vertebra and two healthy vertebrae adjacent to the damaged vertebra. Next, determine the points of insertion of the first screws 4 and second screws 8. For strong fixation of the vertebral-motor segment in the healthy vertebra, which is closer to the cervical spine and adjacent to the damaged vertebra, the first two screws 4 are screwed, and in the healthy vertebra, located further from the cervical of the spine and adjacent to the damaged vertebra, screw the two second screws 8. The protrusions 11 of the hexagonal shape and the second head 19 of the hexagonal shape ensure the first screws 4 and the second screws 8 are screwed into the bone. The first screws 4 and the second screws 8 are inserted into the bodies of the vertebrae 1 through the necks of the vertebrae 3 symmetrically with respect to the spinous processes of the 6 vertebrae. Moreover, cutting edges are made on the first screws 4 and second screws 8, which facilitate the insertion of the first screw and the second screw into the bone. Bone self-polymerizing cement 2 is introduced through the first holes 14 in the first screws 4 and the second holes 23 in the second screws 8. After the cement is polymerized in the vertebral bodies 1, the corresponding nipple 25 is screwed onto the first head 9 of each first screw 4. Corrugated polyvinyl chloride tubes 5 are used with reinforcement 27. Reinforcement - reinforcing a material or structure with another material (the definition of reinforcement is given, for example, in the Great Soviet Encyclopedia on the website http://dic.academic.ru/dic.nsf/bse/65095/, accessed 04.24.2014). To clarify the length of the tube before the operation, measurements are taken according to radiographs or by magnetic resonance imaging. The tubes are filled with bone self-polymerizing cement 2, bent towards the second screws 8 and placed along the spinal segment. Each tube with its free end 28 is inserted into the groove 18 of the corresponding second head 19 of the second screw 8 and is firmly fixed with the third screw 7. After the complete polymerization of the system, a strong connection arises that restores the support of the front and rear columns of the spinal motion segment.

Thus, the operation of transpedicular fixation in the manner described above ensures a reduction in the operational time required for mounting the device due to the smaller number of necessary screws, as well as due to the simple method of fastening the tube.

Claims (1)

A device for percutaneous transpedicular stabilization of the spine, containing two first screws and two second screws, the first screw being provided with a first head connected in series with a means for screwing it in, and a first shaft with a first pointed end, a first external thread is located on the first shaft, on the first head the second external thread is located, the first screws are made with the first through hole made axial, the second screw is equipped with a second head connected in series with the medium In order to screw it in and a second rod with a second pointed end, a third external thread is located on the second rod, the second screws are made with a second through hole made axially, and the first holes and second holes are filled with cement, characterized in that two third screws with a slot and a fourth external thread, and two tubes made of reinforced with a nipple on one end, the second holes on the side of the second head are provided with a first internal thread and are supplemented with a groove, you olnennym open tube nipples connected at their heads to the first by means of corresponding second external threads and second internal threads, partially housed in respective slots second heads secured therein by means of screws and respective third filled with cement.

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