SU1657173A1 - Device for positioning bond fragments - Google Patents

Abstract

This invention relates to surgical osteosynthesis devices. The purpose of the invention is to facilitate adaptation to the conventional holes and reduce bone trauma when the device is removed. The device contains surface plates with counter-curved legs. The plate has a split with diluted edges, and at the end is a grip. The device is made of a material with a shape memory, and the temperature of the phase transition of the gripping material is lower than that of the other parts. The device is applied in a cooled state. 6 Il.

Description

The invention relates to medical technology, namely to traumatological instruments for osteosynthesis.

The aim of the invention is to facilitate adaptation to the burr holes and reduce the trauma of the bone during its removal.

FIG. Figures 1 and 2 show a device for fixing bone fragments, in two projections; in fig. 3 is a section A-A in FIG. in fig. 4 and 5 - the device is in a cooled state, in two projections; fig b - section bb in fig. five.

The device for fixing bone fragments contains the main and additional plate plates 1 and 2 connected by means of a 3 U-shaped gripper at the end of plate 1. Plates 1 and 2 have legs 4 and 5 arched towards each other at the ends. Plate 1 has a longitudinal splitting 6 with divorced edges 7 and 8 in the working position. The plate 2 has a portion 9 lying in the plane of the plate 1 and a portion 10 of trapezoidal cross section, which can be fixed in the gripper 3.

The device is made of material with shape memory, for example, alloys based on titanium nickelide, and the temperature of the phase transition of the gripping material 3 is lower than that of the other parts of the device, which ensures the sequential fixation by the gripper 3 of the plate section 10 and the restoration of the bends of the legs 4 and 5 and their convergence after pre-deforming the grip 3 to ensure free installation of the plate section 10, straightening the legs 4 and 5 and bringing the edges 7 and 8 together in a cooled state.

w

fe

ON SP 41

Vj

with

The device works as follows.

In the mapped bone fragments, trepanation holes are made under legs 4 and 5 of the device. The device is placed in the cooled state in the following sequence: first, straightened leg 4 is installed in one of the bone fragments with flattened edges 7 and 8 splitting b and deformed gripper 3, and then straightened leg 5 is inserted into a heating hole in another bone fragment. and the plate section 10 is installed in the gripper 3. A tampon moistened with an isotonic solution of sodium chloride with a temperature of 35-40 ° C is applied to the gripper 3. In the process of contact heating of the device parts to a temperature of 35 ° C, the shape memory effect, while the grip 3, having a phase transition temperature lower than the rest of the device, restores the set shape first, ensuring a reliable grip of the section 10, and then the other parts of the device restore their original shape, the legs 4 and 5 are arcuately bent in the opposite direction , edges 7 and B of the cleft, splitting the legs 4 and 5 and thus providing a constant dynamic compression of the bone fragments.

After adhesion of the fracture, the device is removed as follows. The gripper 3 is cooled to disengage from section 10, the gripper which is removed

0

five

0

five

0

first, the leg 5, and then the leg 4 is removed. It is possible to remove the device in parts after cutting or sawing the back plates 1 and 2.

The device, by controlling the length of the outboard part, has increased versatility. The detachable outer portions of the device reduce the time required to install the legs in the holes in the bone fragments; device removal after fracture consolidation is simplified.

Claims (1)

Invention Formula A device for fixing bone fragments, containing a bone plate made of a material that has a shape memory effect, with legs at the end and a longitudinal rift in the middle part, characterized in that, in order to facilitate adaptation to the burr hole and reduce injury to the bone during its removal, The forms are made of material with a memory effect, an additional plate with a bent leg at the end and a U-shaped grip mounted on the free-end of the main plate, while the free end is additional The second plate is located in the gripper, and the phase transition temperature of the gripping material is lower than the phase transition temperature of the plate material. M 4i s 2-i / 13 7 V 3 2 7 / 1L FIG. 6