RU2802743C1 - Method of fixing a verteble in spondylolysis and spondylolisthesis of the 1st degree - Google Patents

Abstract

FIELD: medicine; traumatology; orthopedics; neurosurgery.

SUBSTANCE: invention can be used to fix a vertebra in spondylolysis and spondylolisthesis of the 1st degree. Fixation of the spondylolysis zone is carried out by a system that includes two pedicle screws and one rod, curved in an arcuate manner and installed transversely to the longitudinal axis of the spine. Two transpedicular screws are inserted bilaterally into the body of the spondylolysis vertebra, the area of spondylolysis is treated from scar tissue, the rod is modeled by bending in the form of an arc, and it is passed in the transverse direction from the head of the first screw above the lower articular process, under the spinous process and then to the opposite side above the inferior articular process to the head of the second screw. The rod is placed in the screw heads, a compression maneuver is performed and the rod is fixed with nuts to the screw heads, the wounds are sutured.

EFFECT: method ensures stabilization of the vertebrae of the spondylolysis zone, exclusion of hypermobility in this area and creation of conditions for fusion of the spondylolysis zone due to the fact that the arch of the spondylolysis vertebra is fixed by a rod enveloping the spinous process in the spondylolysis zone.

1 cl, 1 dwg, 1 ex

Description

Field of technology.

The invention relates to medicine, to traumatology and orthopedics, neurosurgery, namely spinal surgery and is used in the treatment of patients with spondylolysis and spondylolisthesis, and is used for local fixation of the vertebra.

State of the art.

Spondylolisthesis, the “slipping” or displacement of one vertebra relative to another. There are various methods of fixation of vertebrae for spondylolysis and spondylolisthesis of the 1st degree. There is a known method of fixing the arch during spondylolysis with spongy screws through the spondylolysis zone (J Bone Joint Surg Br. 1970 Aug;52(3):432-7. Author. J E Buck.)

In 1984, E. Morscher developed and described a surgical technique consisting of monosegmental fixation of the spondylolisthesis using a special screw and hook (E. Morscher; B. Gerber; J. Fase (1984). Surgical treatment of spondylolisthesis by bone grafting and direct stabilization of spondylolysis by means of a hook screw., 103(3), 175–178. doi:10.1007/bf00435550). The essence of the method comes down to fixing the vertebra with a special screw and hook. The implant consists of a special hook and screw, with a sponge thread at the tip and a short thread with a triangular profile and two nuts. A skin incision is made along the midline above the spinous processes. The vertebral arches are exposed subperiosteally until the articular processes of the mentum flavum are partially separated from the caudal edge of the vertebral arch. The two hooks are then pushed from a caudal direction over the spinal arch and oriented towards the base of the superior articular process. A hole is drilled at the base of the articular process using a 2.5 mm drill. The direction of the drill diverges laterally approximately 20° from the midplane and is inclined cephalad approximately 40° to the plane of the endplate of the corresponding vertebra. The screw thus appears somewhat dorsal to the spondylolysis and directly at the base of the superior articular process of the vertebra. As special anatomical studies have shown, there is no danger of damage to nerve structures when using the correct technique. The connective tissue in the area of spondylolysis (under certain circumstances, sclerotic bone) is removed and a lightly pressed cancellous or corticocancellous block from the iliac crest is inserted. A special screw is now inserted into a hole drilled into the base of the superior articular process. Two nuts are applied and tightened tightly. Thus, strong compression can be applied to the spondylolysis area and the intervening bone graft. The thread protruding above the nut is cut off.

Tokuhashi et al in 1996 published a modified technique of monosegmental fixation for spondylolysis using a screw-hook combination. (Tokuhashi, Yasuaki; Matsuzaki, Hiromi (1996). Repair of Defects in Spondylolysis by Segmental Pedicular Screw Hook Fixation. Spine, 21(17), 2041–2045. doi:10.1097/00007632-199609010-00023). But, unlike the Morscher method, the screw and hook are connected by a rod on a special offset connector. The technique is as follows: a midline incision is made in the skin and soft tissues and the posterior supporting column is skeletonized at the level of the spondylolysis vertebra. A set of instruments is used to clean the spondylolysis area. Transpedicular screws are inserted into the vertebra bilaterally and laminar hooks are inserted behind the arch. Next, autologous bone is placed in the spondylolysis area and the screw and hook are fixed bilaterally to the offset connector.

Currently, the “gold standard” for vertebral fixation is the universal CD (Cotrel-Dubousset instrumentation) system in its various variants and a huge range of screws and hooks. However, even now there are problems with the availability of sizes and hook options. Known methods for correcting congenital spinal deformities involve the use of modern versions of instruments

For rigid fixation of the arch of a spondylolysis vertebra with hooks, it is necessary to know the thickness of the arch and select a special hook size; therefore, it is necessary to have a large linear row of screws and hooks available.

The essence of the invention.

The goal is to create a universal method for fixing the spondylolysis zone for spondylolysis and spondylolisthesis of the 1st degree.

The technical result consists in fixing the spondylolysis zone with a screw-rod system, which reduces the number of consumables (size range of implants), reduces the financial burden on the clinic, due to the absence of the need to maintain a linear row of hooks.

The technical result is achieved in that in the method of fixing a vertebra during spondylolysis and spondylolisthesis of the 1st degree, in which dorsal access to the posterior column of the spine is performed in accordance with preoperative planning, from an incision in the midline, the vertebra is fixed with an implant. Fixation of the spondylolysis zone is carried out by a system including two transpedicular screws and one rod, bent in an arcuate manner, and installed transversely to the longitudinal axis of the spine; for this, two transpedicular screws are installed bilaterally into the body of the spondylolysis vertebra, the spondylolysis zone is treated from scar tissue, the rod is modeled, bending in the shape arc, and pass it in the transverse direction from the head of the first screw above the lower articular process, under the spinous process, and then to the opposite side above the lower articular process to the head of the second screw, the rod is placed in the heads of the screws, a compression maneuver is performed and the rod is fixed with nuts to the heads screws, wounds are sutured.

The invention is illustrated by the diagram:

Figure 1 – fixation of spondylolysis with two screws and a rod, where indicated:

1- transpedicular screw;

2- rod;

3- spinous process.

Implementation of the invention.

The method is intended to ensure stabilization of the vertebrae in (zones of spondylolysis) with spondylolysis and spondylolisthesis of the 1st degree.

The spondylolysis zone is fixed by a system that includes two transpedicular screws 1 and a rod 2 (Fig. 1), bent in an arcuate manner.

A dorsal approach to the posterior column of the spine is performed in accordance with preoperative planning, from a midline incision. The length of access is determined by the area of instrumentation in the projection of the spondylolysis vertebra. Next, two transpedicular screws 1 are installed in the vertebral body. Installation of transpedicular screws 1 (support points) is carried out bilaterally in accordance with the principles of CD fixation using the free-hand method, into the body of the spondylolysis vertebra. A set of tools perform

treatment of the spondylolysis zone from scar tissue with trimming of the edges. The next step is to model the longitudinal rod 2, bend it in the shape of an arc (arc-shaped beam), and pass it in the transverse direction from the head of the first screw 1 above the lower articular process, under the spinous process, and then to the opposite side above the lower articular process to the head of the second (opposite) ) screw 1. The rod is placed in the heads of the screws, a compression maneuver is performed and the final fixation of the rod with 2 nuts to the heads of screws 1 is performed, the wounds are sutured. Thus, the arch of the spondylolysis vertebra is fixed by rod 2, encircling the spinous process 3, in the spondylolysis zone, eliminating the possibility of hypermobility in this area and creating conditions for fusion of the spondylolysis zone.

Example. Spondylolisthesis L5-S1.

A midline skin incision is made along the line of the spinous processes of the lumbar spine. Following the skin, the lumbothoracic fascia is dissected and the spinous processes of the vertebrae are isolated subperiosteally. Intraoperative radiography is performed. Provide blocking of the L5-S1 segment. The spondylolysis zone is fixed by a system that includes two transpedicular screws 1 and one rod 2, bent in an arcuate manner and installed transversely to the longitudinal axis of the spine. To do this, two transpedicular screws 1 are installed bilaterally into the body of the spondylolysis vertebra, the spondylolysis zone is treated from scar tissue with the edges trimmed, rod 2 is modeled, bent in the shape of an arc, and it is passed in the transverse direction from the head of the first screw above the lower articular process, under the spinous process. process 3, and then to the opposite side above the lower articular process to the head of the second screw, the rod is placed in the heads of screws 1. A compression maneuver is performed, the displacement of the vertebra is eliminated, and the angular deformity is corrected, the normal lordotic curve of the lumbar spine is restored. The rod is fixed with nuts to the heads of the screws; to assess the correct location of the structures and restore the normal axis of the spine, intraoperative radiography is performed in frontal and lateral projections. At the end of the operation, the wound is washed and sutured, leaving active suction drainage.

Using the method reduces the amount of consumables due to the absence of the need to maintain a linear row of hooks or install two longitudinal rods.

Claims (1)

A method for fixing a vertebra during spondylolysis and spondylolisthesis of the 1st degree, in which dorsal access to the posterior column of the spine is performed in accordance with preoperative planning, from an incision along the midline, the vertebra is fixed with an implant, characterized in that the fixation of the spondylolysis zone is carried out by a system including two transpedicular screws and one rod, bent in an arcuate manner and installed transversely to the longitudinal axis of the spine; for this, two transpedicular screws are installed bilaterally into the body of the spondylolysis vertebra, the spondylolysis area is treated from scar tissue, the rod is modeled, bent in the shape of an arc, and it is passed in the transverse direction from the head of the first screw above the lower articular process, under the spinous process and then to the opposite side above the lower articular process to the head of the second screw, the rod is placed in the screw heads, a compression maneuver is performed and the rod is fixed with nuts to the screw heads, the wounds are sutured.