RU189800U1 - Device for fixing the threaded rod to the frame of the external fixation device - Google Patents

Abstract

The invention relates to medical equipment, namely, devices used in traumatology and orthopedics. Its purpose is to increase the efficiency and reduce the time of treatment of patients with bone fractures with an external fixation device. The goal is achieved by using a device for fixing a threaded rod or a Shantz rod to the frame of an external fixation device (AVF), which represents the washers and details of the Ilizarov apparatus set, characterized in that the washers have an S-shaped bend and two sizes, the smallest of which is 1.5 mm, outer diameter 12 mm, hole diameter 7 mm, and the larger thickness 2 mm, outer diameter 23 mm, hole diameter 7.5 mm; two washers of the same size are put on the threaded rod or trench rod and counter-tightening the nuts on both sides with the concave side of the S-shaped bend pressed against the cylindrical part of the AVF parts, fixing the threaded rod or tangency rod to its frame.

Description

The invention relates to medical equipment, namely, devices used in traumatology and orthopedics.

Extrafocal osteosynthesis of long bones of the extremities by external fixation devices (AVF) occupies an important place in orthopedics and traumatology, being the method of choice for open and high-energy fractures, especially as part of polytrauma. The need to quickly stabilize the fracture zone in patients with severe polytrauma is dictated by the fact that this eliminates the mobility of bone fragments, reduces afferent impulsation and blood loss. Therefore, the main requirements for osteosynthesis in the treatment of victims with polytrauma are: minimally invasiveness and early stabilization of bone fragments.

Analogs

External fixation devices are divided into spoke, rod and spoke-rod devices of various modifications. Core AMFs are simpler and their main advantage is the possibility of a relatively fast layout of the outer frame and stabilization of the fracture zone. Spoke AVFs have an optimal combination of atraumatic and stable fixation of bone fragments, sufficient controllability of bone fragments during surgery and in the postoperative period. Spoke-rod apparatus allows to combine the positive sides of the spoke and rod AMF.

Criticism of analogues

- disadvantages of core AVFs are low repositional properties of metal structures with the difficulty of managing bone fragments during osteosynthesis and in the postoperative period, as well as a substantially large bone wound compared to spoke AVF, due to the diameter of the rods (from 4 to 6 mm) and drilled intraosseous channels and , respectively, a decrease in the mechanical strength of the bone;

- the drawbacks of the AMF spokes are the duration of installation and the bulkiness of the external frame of the device, which is not acceptable for primary osteosynthesis in conditions of polytrauma (damage control), the treatment should be divided into several stages. The more severe the injury, the simpler and atraumatic the means of local treatment of fractures in the acute period of a traumatic disease should be;

- spoke-rod AMF is not always applicable without prejudice to its repositional properties and minimally invasiveness, which minimizes the expediency of their use in case of polytrauma. This is due to the fact that not all the fixing units of the AVF apparatus can be mutually adapted technically - both the spoke and rod apparatus among themselves, as well as the individual arrangements of the spoke or rod AMF.

Prototype

Parts of the Ilizarov apparatus kit (Kaplunov OA, Ilizarov transosseous osteosynthesis in traumatology and orthopedics. - M., GEOTAR, 2002) were selected as the prototype device, from which a wide range of layouts can be assembled and which can be adapted to external core devices fixation (AMF). These parts, in particular, can fix the threaded rod or the Shantz rod to the cylindrical part of the AVF parts (Fig. 1), namely short plates (pos. 10), long bolts (pos. 9) and nuts (pos. 6). At the same time, both plates (pos. 10) are pressed to the telescopic rod (pos. 8) by counter-tightening the nuts (pos. 6), which ensure fixation of the Shantz rod (pos. 5) on the telescopic rod (pos. 8).

Criticism of the prototype

Along with the possibility of fixing the threaded rod or the Trench rod to the outer frame of the AVF, the prototype device has significant drawbacks:

- the contact area between the plates (pos. 10), which bring nuts together (pos. 6), and the cylindrical part of the AMF components, for example, the telescopic rod (pos. 8), is too small due to the mismatch between the flat surface of the first and the rounded surface second;

- insufficient contact area between the approximate plates (pos. 10) and the cylindrical part of the AMF components leads to instability of fixation of the latter;

- insufficient contact area between the close plates and the cylindrical part of the AMF components is partially compensated by excessive counter-tightening of two nuts (pos. 6), which can lead to jamming of counter-tightened nuts or breaking the threads on the nuts or bolts (pos. 9);

- cumbersome design and tightening the time of fixing the threaded rod or Trench rod to the outer frame of the AMF.

The purpose of the utility model is to increase the efficiency of treatment of patients with high-energy fractures by external fixation devices (AVF) in conditions of polytrauma. Achievement of the goal is planned due to an increase in technical means and variants of the layout of the fixation units of the AVF, which will expand the range of acceptability of the AMF and the medical tasks it solves.

The essence of the utility model

The goal is achieved by using a device for fixing a threaded rod or a Shants rod to the AMF frame, which is a washer (pos. 1, 2) of two standard sizes (Fig. 2, a, b) and details of the Ilizarov set. The device differs in that the washers have an S-shaped bend (pos. 3), two sizes, the smaller of which (pos. 1) has a thickness of 1.5 mm, an outer diameter of 12 mm, a hole diameter of 7 mm, and a larger one (pos. 2) - thickness 2 mm, outer diameter 23 mm, hole diameter 7.5 mm. In this case, the purpose of the S-shaped bend of the washer is to have the concave side (pos. 3) of two washers of the same size (Fig. 3 and 4), mounted on the Schantz rod (pos. 5) or the threaded rod (pos. 4), cover the cylindrical part of the external frame of the AMF, for example, a threaded rod (pos. 4), a Steinmann rod (pos. 7), a Trench rod (pos. 5) or a telescopic rod (pos. 8), and fasten on it by counter-tightening the nuts ( pos. 6). Two sizes of washers (Fig. 2, a, b) are dictated by the fact that the smaller one (pos. 1) is intended for parts with a diameter of 4 to 8 mm, for example, threaded rods (pos. 4), Shantz rods (pos. 5) or the Steyman rod (pos. 7), and the larger one (pos. 2), respectively, from 6 to 12 mm, for example, a telescopic rod (pos. 8) or the outer frame (pos. 12) of the AMF (Fig. 5, 6).

An example of the application of the utility model

As an example of the application of the utility model, we present the following observation. Patient R., 76 years old, was admitted 06.08.18 g. ROTTs after a catatrauma with a diagnosis: Combined injury. Brain contusion severe. 3 closed chest injury. Multiple fractures of P – X ribs of the right half of the chest along two or more lines with offset and flotation of the “rib panel”. Rupture of the right lung. Right hemopneumothorax. Closed abdominal trauma. Closed comminuted fracture of the middle third of the right femur with displacement of fragments. Multiple abrasions. Traumatic shock III degree.

Against the background of intensive infusion-transfusion therapy, the operation was performed: Toracocentesis according to Bulau on the right; The restoration of the skeleton of the chest with the Kirshner and AVF spokes; Laparocentesis with drainage of the abdominal cavity; Osteosynthesis of the right femur rod AMF.

Due to the presence of multiple rib fractures along two or more lines and flotation of the “rib panel” with increasing phenomena of life-threatening acute respiratory failure, the arrest of which is a priority measure of higher urgency, indications were made for the emergency restoration of chest carcass using our device (FIG . 5, a, b). The device includes (Fig. 5, a) Kirschner spokes (pos. 13), held over a portion of a finned rib fracture and interconnected by a cerclage wire (pos. 14). These interlocking needles were fixed in moderate tension to the threaded rod (pos. 4), which, in turn, was fixed to the outer frame of the AVF (pos. 12) by means of nuts (pos. 6), a bracket (pos. 11), plates (poses 10) and bolts (pos. 9). However, to optimize this design, the threaded rod (pos. 4) was fixed to the outer frame of the AMF (pos. 12) by means of two washers (pos. 2) and nuts (pos. 6), which significantly simplified the restoration of the chest skeleton and increased reliability of this fixation (Fig. 5, 6). In this case, the tension of the threaded rod (pos. 4) for the mutually coupled spokes of Kirchner (pos. 13), connected with each other by means of a cage (pos. 14), was carried out manually within 1.5 kg and secured by counter-tightening of nuts (pos. 6 ) on washers (pos. 2) with an S-shaped bend. At the same time, gross disorders of the biomechanics of respiration were stopped and a negative pressure was created in the chest. The right lung was straightened out, and breathing began to be heard through all the fields. The result of the relief of acute respiratory failure with the help of the AVF was regarded by us as good.

Signs of the utility model, distinctive from the prototype

The design features (distinctive features of the prototype) of the device for fixing the threaded rod or Trench rod to the AMF frame are as follows:

- the presence of washers of two sizes, the smaller of which (pos. 1) has a thickness of 1.5 mm, an outer diameter of 12 mm, a hole diameter of 7 mm, and a larger one (poses of 2) - a thickness of 2 mm, an outer diameter of 23 mm, a hole diameter 7.5 mm;

- Washers have an S-shaped bend;

- the purpose of the S-shaped bend of the washers is to have the concave side (pos. 3) of two washers of the same size, mounted on the trench rod (pos. 5) or the threaded rod (pos. 4), envelop the cylindrical part of the outer frame parts of the AMF;

- The trench rod or threaded rod is fixed on the cylindrical part of the outer frame parts of the AMF by counter-tightening the nuts (pos. 6).

The technical result (advantages over the prototype) device for fixing the threaded rod or rod Shants to the frame of the external fixation device:

- the optimal contact area between the concave surface of S-shaped curved washers, which are screwed together by nuts, and the cylindrical part of the AMF components, for example, a telescopic rod;

- the stability of fixing the threaded rod or Trench rod on the cylindrical part of the AVF parts, due to the optimum contact area between the concave surface of S-shaped curved washers, which are drawn together by nuts, and the cylindrical part of the AVF parts;

- no need for excessive counter-tightening of two nuts and, therefore, preventing jamming of counter-tightened nuts or breaking the thread on the nuts or bolts;

- compactness and lack of bulkiness of the design and tightening the time of fixing the threaded rod or Trench rod to the outer frame of the AMF.

- the presence of washers of two sizes causes better mutual adaptation between the concave surface of S-shaped curved washers, which are screwed together with nuts, and the cylindrical part of AVF parts of different diameters: the smaller washer is optimal for use on Steyman rods, Shantz rods or threaded rods, and a larger washer size - on the cylindrical part of the telescopic rod or the outer frame of the rod AMF;

- the best mutual adaptation of the fixing units of the AVF apparatus - both the spoke and rod apparatus among themselves, and the individual arrangements of the spoke or rod AMF;

- increase in technical means and variants of arrangements for fixing knots of the AVF, which expands the range of acceptability of the AVF and medical problems solved with it.

Thus, the proposed device allows to increase the efficiency of treatment of patients with high-energy fractures by external fixation devices in conditions of polytrauma.

Information taken into account:

1) G. Ilizarov Clinical and theoretical aspects of transosseous and distraction osteosynthesis // Theoretical and practical aspects of transosseous and distraction osteosynthesis. - Kurgan, 1976. - p. 14-24;

2) Devyatov A.A. Transosseous osteosynthesis. - Chisinau, - 1990. - 316 p .;

3) Golyakhovsky V., Frenkel V. Guide to transosseous osteosynthesis using the Ilizarov method. - S.-Pb., - 1999. - 270 p .;

4) Kaplunov O.A. Transosseous osteosynthesis according to Ilizarov in traumatology and orthopedics. - M, GEOTAR, 2002. - device prototype.

Claims (1)

A device for fixing the threaded rod to the cylindrical part of the external fixation device, characterized in that it consists of two washers for putting on the threaded rod and nuts for pressing said washers, while the washers have an S-shaped bend for pressing the concave side of the S-shaped bend to the cylindrical part of the external fixation device, each washer is made 1.5 mm thick, with an outer diameter of 12 mm, a hole diameter of 7 mm, and two washers are put on the threaded rod and counter-tightening of nuts from both sides of the concave side of the S-shaped bend pressed against the cylindrical part of the external fixation device parts, fixing the threaded rod.

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