SU1532014A1 - Washer for screw used in osteosynthesis - Google Patents

Abstract

The invention relates to medicine and is intended to ensure uniform distribution of pressure on the bone when using screws for osteosynthesis. A screw 3 is inserted into the opening of the plate 1, which is hingedly connected with two parallel slat plates 7 and 8 with a rod 4 with stop heads. After inserting the screw 3 into the bone, the washer is cooled and the required angle of inclination is established between the plate 1 and the slats. After the contact heating of the washer, the rod 4, made of a material having a shape memory effect, shortens in length and wedges the hinge. The screw head 3 is pressed against the plate 1.

Description

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The invention relates to medical technology and is intended for use with devices for osteosynthesis.

lle. ibK) of the invention is to provide a uniform distribution of pressure on the bone at different angles of inclination of the screw.

FIG. 1 shows a washer to an osteosynthesis screw; in fig. 2 - the same, in the cold state.

The washer for osteosynthesis comprises a plate 1 with an aperture 2, for example, a screw 3 for osteosynthesis. With the plate 1 by means of the rod 4 with the stop heads 5, 6 at the ends parallel bar plates 7, 8, installed with a gap 9 under the screw 3, are interconnected. The bars 7, 8 can be bent according to curve B11: and (e). (Core 4 with stop heads 5, 6 is made of a material with a shape memory effect, for example, nickel-titanium g () sp.chava, and in the cooled state ei o length by K) 15% more than in heated ) state. In the cooled state, the plate 1 and the plate strips 7, M MoiA T move freely between each other. u. 2), and in the heating process is a reduction of the rod 4 and jamming N1arnirnogo compound that provides reliable fixation plates 1 and extramedullary strips 7, 8 relative to each other.

1 using a washer with a screw for osgeosynthesis before its introduction into bone fragments 10, 1 I on the screw stem 3 mouth

nav Plate I is pressed, while the rod 4 is located in the gap 9 between the plate strips 7, 8. The screw is inserted into the bone fragments 10, 11, the tongue is cooled, for example, by irrigation with chloroethyl, and the rod 4 is lengthened. Between the plate 1 and the planks 7, 8, set the required angle of inclination and hold for some time. When the core 4 is heated to ambient temperature, the memory effect of the nickelide-titanium alloy appears, the core 4 acquires a predetermined (i.e., initial) shape - its reduction takes place, and when the stop heads 5, 6 come together, the hinge joint is wedged, ensuring reliable mutual fixation of the plate 1 and the plank plates 7, 8. Then continue the introduction of the screw into the bone fragments 10, 11 until the plate 1 is in tight contact with the screw head 3.

Claims (1)

Invention Formula The washer to the screw for osteosynthesis, having a central hole, characterized in that, in order to ensure uniform distribution of pressure on the bone at any angles of inclination of the screw, the puck is made in the form of a plate and provided with at least two parallel outboard slats, which are pivotally connected to the plate by means of a rod with stop heads at the ends, made of a material with a shape memory effect, with the possibility of reducing the length and jamming of the hinge.