RU2028110C1 - Apparatus for treatment diaphysial fractures of long tubular bones - Google Patents

Abstract

FIELD: traumatology and orthopedics. SUBSTANCE: apparatus has braces 1 with spines on its inner side, joined by compressing assembly. At one side of the braces 1 the spines are arranged on the inserts 3, mounted in the braces 1 with possibility of motion and fixation with the aid of eccentric clamps, secured to the braces. The compressing assembly has pairs of sleeve pieces with the eccentric clamps 9, arranged in openings of these pieces. EFFECT: enhanced structure of the apparatus. 1 cl, 4 dwg

Description

 The invention relates to traumatology and orthopedics and can be used in surgical treatment of fractures of tubular bones.

 A device for closed compression-distraction osteosynthesis of diaphyseal fractures [1], containing frames, rods, adjusting screws, spokes with stops, spoke holders, including a bolt, tension screw and nut.

 The device also contains internal repository cases and external repository cases, pairwise interconnected by frames with adjusting screws and movably located on the bars of the scale.

The disadvantages of the described device:
relative design complexity;
relatively high invasiveness associated with transosseous holding of numerous spokes.

 Also known apparatus for reposition and fixation of bone fragments [2], containing two supports in the form of brackets with threaded spokes with bolts, washers and a rod. The reposition unit is made in the form of a bracket connected by means of a bar to a slider in which a threaded rod is installed. On the bracket, strap and slider are made scales.

The disadvantages of this analog device are as follows:
relative design complexity;
relatively high invasiveness.

 The closest in technical essence and the achieved result is a device for osteosynthesis of tubular bones [3], adopted as a prototype. This device consists of two half rings that span a bone more than half of its perimeter in cross section. The half rings are fixed with a conical pin.

In order to ensure the self-locking tapered pin if jamming is configured with the inclination angle ^of 7. On one side, the pin rests on the bone, and the second side of the pin comes in contact with ^the surfaces of the half-rings inclined at an angle of 7 °. The ends of the semirings are made pointed, with the possibility of separation of soft tissues from the bone. On the inner surface of the semirings, grooves are made in the form of a transverse notch, which allows to reduce the contact area of the semicircles with the bone and increase the specific load on the bone at the contact points, which ultimately leads to better bone coverage and improved anchoring of the bone. A longitudinal notch on the inside of the half rings allows better fixation of the bone. The half-branches are made with bends at the end, forming a hinge in which a conical pin is installed.

The disadvantages of the prototype device:
insufficiently wide functionality associated with the lack of compressive force along the axis of the fragments and the inability to treat transverse fractures;
insufficient reliability of the operation of the conical pin during the entire treatment (it may partially exit towards a larger diameter due to the presence of random loads);
the fact that on one side the pin rests directly on the bone (periosteum) and interacts with metal bends on the other side, the jaw creates, firstly, uncertainty regarding the angle of self-braking (conical pin-jaw - one coefficient of friction, and the pin-bone - other), secondly, the periosteum under the pin is dead in the process of treatment;
some inconvenience in use (the need for a raspator, special notches for it).

 The purpose of the invention is the provision of the possibility of treating transverse fractures by compression of fragments.

 Figure 1 shows a General view of the device (front view) with a cut along the axis of the eccentric of the compression unit; figure 2 is the same, a top view; figure 3 is a transverse section of a bracket equipped with liners and an eccentric, section AA in figure 1; figure 4 is a section along the axes of the liners (section BB in figure 3).

 A device for treating diaphyseal fractures of long tubular bones consists of two metal staples 1 and 1a, equipped with clamping eccentrics 2 and 2a, has a movable insert 3 with sharp spikes or a functional thread replacing them and a fixed insert 4 with spikes.

 The eccentric 5, directly contacts the surface "G" (figure 4) of his cam with the liner 3. There are two such eccentrics - left and right. The brackets 1 and 1a are interconnected by a compression unit (Fig. 1), consisting of two pairs of ears 6 and 7, (Fig. 2), and the ears 6 are pivotally attached to the bracket 1, and the ears 7 are rigidly attached to the bracket 1a. All cam 5 have square turnkey shanks 8, 8a, 8b. When the ears 6 and 7 are axially aligned, an eccentric 5 is inserted in them. There are 4 eccentrics in total 5 in the device.

 The working surfaces of the cam of the eccentrics are indicated by the letter "G" (Fig. 2 and 4). A possible stroke of the eccentrics is visible in FIGS. 2 and 4.

 The working surface "G" of the cams 9 of the eccentrics is made with two different lifting angles as the cam moves - at first a large lifting angle, then much smaller, working only on the clamp. Sharp spikes 10 are shown on the inner surfaces of the liners 3 and 4.

 A device for treating bone fractures is used as follows.

 At the ends of previously repaired bone fragments (distal and proximal), staples 1 and 1a are alternately put on. Previously, the liners 3 with the cams 9 are in the loose state (figure 3), i.e. in the far right.

Having installed the left bracket (Fig. 1) with an opening on the eyelet 6, the right bracket 1a is installed so that the eccentric 8 fits with its cam 9 into the eyelet hole 6. By turning the shank 8 and 8a of the eccentric 2 and 2a, the left and right brackets are fixed at the ends bone fragments. In this case, the sharp spikes of 10 inserts 3 and 4 dig into the periosteum and reach the cortical layer of the bone, carrying out rigid fastening of brackets at the ends of the fragments. A slight (tenths of mm) spring clamps keeps these clamps in tension, preventing spontaneous self-disengagement of the cam clamps. It also serves as a self-locking and execution conditions for steel rubbing pairs (angle lifting end of the stroke ^of the cam ≅5).

 Then the fragments are pulled together with the help of a compression unit, creating constant axial compression by turning the shank 8b.

 The dimensions of the device (primarily brackets and inserts) are selected according to the size of the patient’s bones (i.e., taking into account anthropological data).

 Thus, when using the inventive device for the treatment of diaphyseal fractures of long tubular bones, the functionality has been expanded to treat not only oblique fractures, but also transverse ones. The reliability of the connection of parts in the compression unit has been increased due to the certainty of the metal-metal friction coefficients. Ease of use is improved - it becomes possible to clamp fragments simultaneously, and then simultaneously apply a compressive force with fixation of this force.

 The trauma of the device is reduced (there is no wedge directly placed on the periosteum for the entire duration of treatment). All of these factors - the components of the positive effect of the use of the claimed device - can improve the stability of osteosynthesis in all types of diaphyseal fractures of long tubular bones.

Claims (1)

 DEVICE FOR TREATMENT OF DIAPHYSIS FRACTURES OF LONG TUBULAR BONES, containing connected brackets with spikes on the inside, characterized in that, in order to provide the possibility of treating transverse fractures by compression of fragments, the device is equipped with a compression unit in the form of pairs of ears connected to brackets, in the holes of which are installed eccentric clamps, the brackets are made of metal, and the spikes on one side of the brackets are made on the inserts placed in the brackets with the ability to move and fix using ecc ntrikovyh clamps mounted on brackets.

Images