RU2336842C2 - SUV-Frame UNIT FOR TRANSOSSEOUS OSTEOSYNTHESIS - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: unit contains two rings and six bars. Latter interconnect rings. The unit has cardan joints, three of which are mounted on each ring. The bars are made of rod one end of which has rotating clear threaded portion. The bars are connected to the cardan joints so that the threaded portion of the bar was on the cardan joint side to which the bar is connected. The neigbouring bars from the opposite rings are interconnected by an uniaxial rotary joint. When the bar threaded portion rotates the uniaxial rotary joint moves along the bar.

EFFECT: prevention of necessity to replace bars and to adjust bar length during apposition process to eliminate small and large deformations.

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Description

The invention relates to medicine, namely to traumatology and orthopedics, and can be used to treat fractures, multiplanar deformities, false joints of bones.

The well-known "Ilizarov apparatus" (Kaplunov O.A .., "Transosseous osteosynthesis according to Ilizarov in traumatology and orthopedics", "GEOTAR-MED", M. - 2002, pp. 13-31), which consists of several stainless steel rings to which transosseous elements (knitting needles, screw rods) are attached with special clamps. The rings of the Ilizarov apparatus are interconnected by connecting rods or hinges. The disadvantages of this device are:

1. The need for partial remounting of the apparatus when eliminating multi-plane deformations.

2. When eliminating each component of the deformation, x-ray control is necessary, which increases the radiation dose to the patient and medical personnel.

3. When using replacement knitting needles, the layout of the apparatus should include two base and two reposition-fixation supports. This increases the bulkiness of the structure.

Closest to the proposed is the C. Taylor apparatus - Taylor Spatial Frame (C. Radler, Limb lengthening and deformity correction using the Taylor Spatial Frame: A retrospective review of 48 cases / C. Radler, R. Ganer, M. Manner, HGPetje , F. Grill // Journal of Bone and Joint Surgery, Jan. 2003), which is an external fixation device based on two rings interconnected by six telescopic rods (striations). The apparatus is based on a hexapod system equipped with computer navigation, which provides accurate mathematical calculation for reposition of fragments.

The disadvantages of this device are:

1. When eliminating gross deformation, there is a high probability of replacing a stratum of one size with another, which can lead to secondary displacement of fragments in the apparatus.

2. The length of the stratum of the minimum size (91 mm) for cases of eliminating gross angular deformation of the bones may be too large, i.e. It will not be possible to assemble the device.

3. Strata according to the methodology should be located strictly in certain places on the rings, which excludes the possibility of their transfer, if necessary, to carry out a transosseous element in this position. This can lead to a decrease in the rigidity of fixation of bone fragments.

4. Strata have six fixation points on each ring, which limits the possible locations for transosseous elements.

These disadvantages are deprived of the proposed device.

The technical result of the invention is to prevent the need to replace the rods, as well as regulating the length of the rods during the reposition process while eliminating deformations of both large and small sizes.

The result of the invention is achieved by the fact that in the proposed apparatus there is no need to replace the connecting rods during the reposition period, the rods have three fixation points on each ring, if necessary, the fixation point of the rods can be transferred to a nearby hole on the ring; the rods of the apparatus consist of a rod having a freely rotating threaded part at one end, connected by means of a threaded pair and a uniaxial hinge.

The figures depict:

Figure 1 is a diagram of an apparatus for transosseous osteosynthesis "SUV-Frame", where:

1 - the upper ring of the external fixation apparatus;

2 - the lower ring of the external fixation apparatus;

3 - cardan joint;

4 - connecting rod;

5 - single-axis joint;

L is the amount of displacement of the uniaxial joint along the rod.

Figure 2 Scheme of the main node of the apparatus for transosseous osteosynthesis, where:

2 - a ring of the external fixation apparatus;

3 - cardan joint;

5 - single-axis joint;

6 - threaded pair;

7 - a rod connected to a threaded pair through a single-axis hinge;

8 - a rod connected to a threaded pair;

9 - freely rotating threaded part.

The device is used as follows. After bone fragments are fixed relative to the lower and upper rings, the main part of the device is mounted. For this, three cardan joints are fixed on each ring. The rods are attached to the cardan joints so that the threaded portion of the rod is on the side of the cardan joint that the rod is attached to. Then, by closing the uniaxial hinge, adjacent rods coming from opposite rings are connected in pairs. As a result of the actions performed, a fixed connection of the upper and lower rings is ensured. Changing the position of the upper ring relative to the lower is achieved by changing the position of the uniaxial hinge. When the threaded part of the rod rotates, the uniaxial hinge moves along the rod. When installing the apparatus, such a length of the rods is laid that will allow repositioning without the need for replacement.

Claims (1)

The device for transosseous osteosynthesis, containing two rings and six rods, the latter connect the rings to each other, characterized in that it has cardans that are attached three on each ring, the rods are made of a rod having a freely rotating threaded part at one end, to the cardans the rods are connected so that the threaded part of the rod is on the side of the cardan, to which the rod is attached, and the adjacent rods coming from opposite rings are connected by a single-axis hinge, and when rotating The threaded part of the rod moves the uniaxial hinge along the rod.

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