SU950360A1 - Intraosteal fixing device for treating long tubular bone fractures - Google Patents

Description

one

This invention relates to medicine, namely to traumatology and orthopedics.

An intraosseous fixator for the treatment of fractures of long tubular bones is known, which comprises a coaxially arranged hollow body and a rod with conical 5 protrusions and elements for fixing fragments 1.

A disadvantage of the known device is that it does not provide stable fixation of bone fragments;

The aim of the invention is to ensure stable fixation of bone fragments, taking into account the physiological characteristics of the bone marrow canal.

The goal is achieved by the fact that in the intraosseous fixator for treatment of fractures of long tubular bones, containing a coaxially arranged hollow body and a rod with conical protrusions and fragments fixation elements, the rod is spring-loaded relative to the JQ body, and the fixation elements of fragments are made in the form of petals in the walls of the body and they have thrust pads on the inner surface and notches on the outer surface, while the thrust pads interact with the conical protrusions.

FIG. 1 shows the intraosseous fixative, with depressed petals; in fig. 2 - the same, with extended petals; in fig. 3 is a section A-A in FIG. 2

The intraosseous fixator comprises a body 1 having a cylindrical shape and a rod 2. On body 1 there are several rows of petals 3, the bases of which are integral with the body 1 itself. Petals 3 are cut out of body 1, they have the same length and width and are removed from each other around the circumference of the housing 1 at the same distance. The preferred length of the petals is 3-4 cm, transverse incisions are applied on their outer surface to improve adhesion to the bone. On the inner surface of the petals 3, stop pads 4 are made, which may have a different shape: half-cone, sphere, etc. The height of the stop pads 4 is the same for all petals, except for the last row. In the last row of lobes 3 in the distal part of the fixer, the height of the thrust pads 4 is larger and shifted closer to the base of the lobes 3. As a result, the span of the last row of lobes increases in the metafizar part of the bone, where the bone marrow channel is wider than diaphase, which increases the reliability of fixation of fragments.

On rod 2, against each row of petals 3, conical protrusions 5 are made, which pass into cylindrical sections with a diameter almost equal to the inner diameter of housing 1. The presence of cylindrical sections on the rod allows closing the “windows under the petals 3”, thus preventing tissue ingrowth into latch cavity. In the distal part of the rod 2 there is a cone-shaped stop of the stroke 6, in which a recess 14 for a wire spike is made.

In the proximal part, the housing 1 and the latch rod 2 are threaded 7 and 8 under the stabilizing nut 15, in which, respectively, the threads 17 and 18 are made. On the stabilizing nut 15 there is a recess 16 for gripping the tool when removing the latch from the bone.

As a means of ensuring constant pressure on the petals 3, a spring 9 is used, placed between the washers 10 and 11 on the proximal part of the retainer. The pressure force can be adjusted by the nut 12. The uppermost portion of the proximal part of the rod 2 is designed as a polyhedron 13. The fixer is used as follows.

For insertion of the fixer, it is selected according to the thickness and length of the bone channel, i.e. the fixer may have various sizes. The slight discrepancy between the diameter of the medullary canal and the diameter of the fixture body is eliminated by longitudinal drilling. Drilling creates at the same time a straightness to 1 anal. The channel is drilled in both fragments.

. The core 2 is inserted into the retainer body 1 in such a way that the outer surface of the petals 3 is below the outer surface of the body 1. In this position, the stabilizing nut 15 is screwed onto the threads 7 and 8 of the bar 2 and body 1. 14, start holding the retainer. The blows of the hammer on the stabilizing nut 15. the lock is inserted into the medullary canal until

stabilizing nut 15. Stabilizing nut 15 is removed and a washer 10, a spring 9, a washer 11 are placed on the proximal part of the retainer, and the nut 12 is screwed onto the thread 7 of the rod 2.

Placing the key on the polyhedron 13 of the rod 2, rotate the nut 12, the rod 2 moves upwards, while the protrusions 4 of the body petals 3 move along the conical sections 5 of the rod 2. The pressure is transmitted to the petals 3, which, in turn, evenly press the walls bone marrow canal. The petals 3 of the lower row are extended according to the construction of a larger distance and fill the cone-expanding channel of the metaphysis. In the diaphysis, the petals 3 come out of each row evenly. The spring 9 under the nut 12 provides a constant pressure of the rod 2 on the petals 3.

After splicing of the fragments, the retainer is removed.

The proposed retainer provides physiological conditions for fusion of bone fragments in various types of fractures: oblique, helical, comminuted, transverse, since the petals act on the walls of the bone marrow canal along its entire length in three planes, while ensuring reliable fixation of bone fragments.

Claims (1)

Invention Formula An intraosseous fixator for the treatment of fractures of long tubular bones, containing coaxially arranged hollow body and stem with conical protrusions and elements of fixation of fragments, characterized in that, in order to ensure stable fixation of bone fragments taking into account physiological features, bone marrow channel, the stem is spring-loaded relative to the body, and the elements of fixation of fragments are made in the form of petals in the walls of the body and have thrust pads on the inner surface This thrust pads interact with conical protrusions. Sources of information taken into account in the examination 1. USSR author's certificate for application No. 28 7998/13, cl. A 61 B 17/18, 01.23.80 Izj