RU2410054C1 - Fragment reduction and retention apparatus - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: apparatus represents a bone-holding clamp and consists of a working part, branches and a rack mechanism. The working part represents elastic curved fenestrated sponges of the thickness 2 mm and width 30 mm. The sponges are crescent with two divergent pins, mutual concavity, smooth curve and spurs on a concave side. The five teeth rack mechanism enables to vary a distance between the sponges and to graduate fragment gripping strength within one to five.

EFFECT: higher clinical effectiveness in orthopaedic-traumatic patients undergoing an open osteosynthesis surgery.

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Description

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

With open osteosynthesis of fractures or false joints of bones, the success of the operation depends on the quality of reposition and fixation of bone fragments. To capture bone fragments, manipulate them and hold them in a repositional position during the osteosynthesis operation, there are special tools, the most famous of which are bone holders Lambote, Boycheva and Lane (Boychev B., Conforti B., Chokanov K. Operative orthopedics and traumatology. - 2nd ed., Revised and supplemented - DI "Medicine and Physical Education", - Sofia, 1958, - 832. - P.18-22). The latter of them is preferable, since it differs from the first in the smaller thickness of the working part (jaws) of the instrument and, therefore, atraumatic with a smaller length of skeletonization of bone fragments necessary for their capture, and from the second, in addition, the rounded inner surface of the jaws corresponding to the tubular cross section bones. Therefore, as the closest analogue and prototype of the proposed device selected bone holder Lane. Along with the ability to capture, manipulate and retain bone fragments, this device has significant disadvantages:

1) insufficient width of the working jaws of the instrument (not more than 12 mm), which, firstly, limits the ability to simultaneously capture and hold both bone fragments with a transverse or short oblique fracture line, and secondly, increases the load per unit bone area, increasing the danger of crushing or cracking of bone fragments, especially with their osteoporosis;

2) the likelihood of damage to bone fragments increases due to the rigidity of the jaws of the instrument with a rigid capture of bone fragments;

3) the excess thickness of the sponges (more than 10 mm), in addition to their rigidity, necessitates an increase in the volume of the wound and skeletonization of bone fragments over a greater length for their capture;

4) to keep bone fragments in the reached position, at the ends of the handles of the instrument there is a special limiter consisting of a strap with recesses (teeth) on one handle and a spike corresponding to the depth of these recesses on the other; the disadvantage of this limiter is, firstly, the unreliability of the tenon fixation in the notch with frequent loss of retention of the repositional position of the bone fragments, and secondly, the inconvenience of manipulating this mechanism with unnecessary waste of intraoperative time and the need for constant holding of the tool by an assistant;

5) the advisability of using only on tubular bones, the cross section of which corresponds to the concavity of the working jaws of the tool.

To prevent these drawbacks, a device is proposed (Fig. 1) for reposition and retention of bone fragments during osteosynthesis of long and short tubular and flat bones, which is a bone holder consisting of a working part (1, 2, 3) and a jaw (4) with a cleamer ( 5).

The working part (Fig. 2, a, b) of the device is represented by graduated jaws (1) with a thickness of 2 mm with mutual concavity, smooth bending and teeth (2) on their concave surface (Fig. 2, a). The thickness of the sponges of 2 mm prevents the need for an increase in the surgical wound and wide skeletonization of bone fragments for their capture and retention. Atraumaticity of the device, except for the termination (3), is due to the elasticity of the sponges (1) and branches (4) of the instrument, which excludes crushing and cracking of bone fragments during their capture, the springiness (damping) of which eliminates the excess of compression, evenly distributed over the entire contact area of the sponges and bone surface. The width of the jaws (1) of the instrument is 30 mm, and, therefore, the load per unit area of contact between the jaws and the captured bone excludes damage to the latter. The concavity and the presence of teeth (2) of the inner surface of the jaws of the device prevents slipping of the jaws from the bone when manipulating bone fragments. The rationality of the finality (3) of the working part of the instrument (Fig.2, b) is due to the fact that it allows you to combine the greatest coverage of bone fragments (with the retention of both bone fragments even with a transverse or short oblique fracture line) and the ability to control their condition and position under the sponges . At the same time, osteoperforation can be performed with knitting needles or drills and osteosynthesis without moving the tool lips and without losing the repositional position of the bone fragments. In addition, the fineness (3) of the jaws corresponds to one of the basic rules of structural mechanics: a combination of maximum structural strength with the least material consumption. The terminal sponges have a crescent shape with two diverging pointed spikes, which is rational because of their larger size (30 mm between the spikes) and, accordingly, the coverage of bone fragments, as well as the proximity to the shape of an isosceles triangle as the most stable geometric figure. Therefore, this device can be used not only for optimal capture and retention of fragments of tubular bones (both long and short), but also fragments of flat bones: sternum, scapula, pelvis, etc.

In addition to the working part, the device has jaws (4) with a rack (5) - a special mechanism for fixing the jaws in a closed state, as with conventional hemostatic clamps (Kocher, Billroth or Pean). Clemeliere is designed to, on the one hand, make it more convenient to manipulate bone fragments during their reposition, and on the other, to keep them in a repositional position during osteosynthesis. The achieved capture of bone fragments is held by the clipped teeth of the cleamer, and the number of teeth of the clamera (five) allows you to vary the grip strength in a wide range - from one to five. At the same time, the hands of the assistant are released. This device is optimal for osteosynthesis of bones, the diameter (or thickness - if it is flat bones) of which varies from 5 to 30 mm, for example, the clavicle, shoulder and bones of the forearm. Osteosynthesis can be of various types, including intramedullary (figure 3) or bone (figure 4-6).

As an example of the use of this device, the following observation. Patient K, 29 years old, was admitted to the traumatology department of the Republican Orthopedic Traumatology Center (RTC) on 01.30.09 with a diagnosis of Closed transverse fracture of the middle third of the left radial bone. 02.02.09, the operation was performed as planned: Bone osteosynthesis of the left radial bone with a grooved plate on 4 screws. Moreover, during the operation, bone fragments were repaired and fixed in repositional position using the proposed device, consisting of a working part represented by elastic curved fenestrated sponges with a thickness of 2 mm and a width of 30 mm, having a crescent shape with two diverging spikes, with mutual concavity, smooth with a bend and denticles on the concave side, and jaws with a cleaver with five teeth that allow you to vary the distance between the jaws and measure the grip strength of bone fragments in the range from one about to five. The ease of use of a device with optimal manipulation properties during reposition and fixation of bone fragments allowed the operation to be performed atraumatically and quickly without technical difficulties (Figs. 4, 5, 6). The wound is sutured in layers. A plaster cast was applied, in which the patient was discharged on 02/12/09 after removing the sutures and primary healing of the wound. Fracture healed in a timely manner. The function of the upper limb is fully restored. The result of treatment is regarded by us as good.

Therefore, the structural differences and advantages of the proposed device are as follows:

1) The injuries of the device, due to the fact that the working jaws are 2 mm thick and 30 mm wide: the thickness of the jaws prevents the need for an increase in the surgical wound and wide skeletonation of bone fragments for their capture and retention, and the width reduces the load of the jaws per unit area of the captured bone;

2) The exclusion of crushing and cracking of the bone, which, in addition to the above circumstances, is due to the elasticity of the lips of the device. So, the depreciation (damping) properties of the device sponges make it possible to level excess compression, which is evenly distributed over the entire area of contact with the bone;

3) The possibility of stable capture and holding in repositional position by the sponges of the instrument of one or both bone fragments, not only in the longitudinal, spiral or oblique, but also in the transverse plane of the fracture. This is due to the width of the working jaws more than 20 mm and the presence of teeth on their concave side, which determine the best adhesion and stable holding by the tool of a smooth and rounded surface of bone fragments;

4) The extremity of the working part of the instrument allows you to combine the greatest coverage of bone fragments with the ability to control their condition and position under the jaws of the device. This allows, for example, to perform osteoperforation with knitting needles or drills and osteosynthesis of bone fragments without losing their reposition and without moving the jaws of the device. In addition, the finality of the latter corresponds to the rule of structural mechanics: achieving maximum structural strength at the lowest material cost.

5) The shape of a crescent of graduated jaws with two diverging pointed spikes is rational due to their larger size (30 mm between the spikes) and, accordingly, the coverage of bone fragments, as well as their proximity to the shape of an isosceles triangle as the most stable geometric figure. Therefore, this device can be used not only for optimal capture and retention of fragments of tubular bones, but also fragments of flat bones;

6) The presence of cleamers with five teeth allows you to vary the distance between the jaws of the device depending on the size (diameter and thickness) of the bone fragments (from 5 to 30 mm) and the degree of grip strength in the range from one tooth to five. At the same time, the simplicity and speed of the action of the cleamer mechanism by snapping the device on the bone surface and removing it significantly improves the handling properties of the device and minimizes the intraoperative cost of time;

7) No need to retain repaired bone fragments during osteosynthesis and the ability to free the hands of an assistant.

Thus, the proposed device can improve the quality of open osteosynthesis and create optimal conditions for increasing the effectiveness of treatment of patients with whom it is used.

Claims (1)

A device for reposition and retention of bone fragments during osteosynthesis of long and short tubular and flat bones, which is a bone holder, characterized in that it consists of a working part, represented by elastic curved fenestrated sponges with a thickness of 2 mm and a width of 30 mm, having the shape of a crescent with two diverging spikes, with mutual concavity, a smooth bend and with teeth on the concave side, and a jaw with a cleaver with five teeth, allowing you to vary the distance between the jaws and measure the strength for grasping bone fragments ranging from one to five.

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