RU2259175C1 - Fastener usable in osteoplasty operations - Google Patents

Abstract

FIELD: medical engineering.

SUBSTANCE: device has metal plate having widened middle part, at least three pedicles and at least four holes in the middle part, one of them being central and one available on each of the pedicles. At least one of the pedicles has flexible member between the middle part and the nearest hole. It is manufactured as flat helical spiral with turn angle of 180°.

EFFECT: accelerated surgical operation; reliable connection of bone fragments; reduced risk of traumatic complications.

2 dwg

Description

The invention relates to medicine, namely to medical equipment, and can be used in maxillofacial surgery in the treatment of patients with developmental abnormalities or acquired deformations of the lower jaw.

A number of devices or fasteners are known to be used in maxillofacial surgery. For example, a bracket for osteosynthesis (USSR AS No. 1152582, and 61 B 17/58, 1985), made of material with shape memory, is a plate with an opening and curved legs at the ends arcuately bent. At the place where the hole was made, the plate has an extension, and the legs (at least one pair) are bent towards each other, and the other pair is in opposite directions. This device (bracket) is successfully used in compression osteosynthesis to fix bone fragments or fragments.

However, this device has disadvantages:

- the impossibility of fixing with one device more than two bone fragments;

- a device made of a material with a shape memory of this design is rather laborious to manufacture, during installation it requires additional manipulations (cooling with cold saline or chloroethyl, deformation, etc.), which affects the duration of the operation;

- the inability to simulate the device during the operation, depending on the topography and bone size.

The stripper for bone grafting (Bezrukov V.M., Sukachev V.A., Shamsutdinov A.Kh. Bone grafting of the lower jaw / Manual of surgical dentistry and maxillofacial surgery under the editorship of Bezrukov Z.U., Robustova TG, M .: Medicine, 2000. - T.2. - C.175-188), which is a U-shaped titanium plate with holes for screws. The plate is placed on fragments of the jaw and bone graft and fixed with screws.

This scraper has the following disadvantages:

- when using a graft of significant size, the scraper in one instance cannot rigidly and reliably fix three fragments simultaneously (two osteotomized fragments of the jaw and a bone graft between them). The use of a second similar or another design significantly lengthens the operation time, increases the morbidity, without guaranteeing the necessary rigidity and reliability of the bonding of all bone grafts

- rotational mobility of the graft is not excluded.

These shortcomings are absent in the bone grafting fastener (RF patent No. 2207083, A 61 B 17/80, 2002), adopted as a prototype, as being closest in its technical solution to the proposed invention. The fastener is a metal (for example, titanium) plate with an expanded middle part and at least three legs, provided with at least four holes in the middle part, including one central, and holes on each of the legs. The legs form two obtuse angles located opposite each other, and one or two sharp. On each leg there are holes located on one straight line with at least two holes of the middle part (central and off-center, closest to the leg). The legs forming an acute angle can be bent in the plane of the plate towards each other in the region of the hole close to the middle part. In this case, the ends of the legs can be pointed and bent in one direction relative to the plane of the plate.

This prototype fastener provides reliable fixation of three bone fragments, excludes any transplant mobility, and is convenient for installation. However, the protector fastener has a drawback that limits its use and increases the duration and invasiveness of the operation. A fastener of this design has limited possibilities for modeling it in the plane of the plate and changing the location on the bone of the fixing legs. This disadvantage is due to the stiffness of the legs in all directions, except for the perpendicular plane of the fastener.

The objective of the invention is to provide a fastener for bone grafting, ensuring the reliability of the fastening of all fragments and excluding the rotational mobility of the graft. In addition, trauma is reduced and the duration of the operation is reduced due to the possibility of modeling in shape during the operation, depending on the relief and size of the bone, which in turn provides versatility and ease of use.

The technical result is achieved due to the fact that in the known fastener for bone grafting, made in the form of a metal plate with an expanded middle part and at least three legs, equipped with at least four holes in the middle part, including one central , and holes on each of the legs, at least one of the legs is equipped with a flexible element in the area between the middle part and the hole closest to it, made in the form of a flat helical spiral with an angle of rotation of 180 degrees. The presence of one or more flexible elements in the scraper allows you to bend the legs in any direction, i.e. to model a bond depending on the relief and the size of the bone. The flexibility of this element is due to the inconsistency of the value of the moment of inertia (or moment of resistance) of its cross section along the length in any possible direction due to the design of the element in the form of a flat helical spiral, and the spiral with a rotation angle of 180 degrees ensures the flatness of the fastener. Due to the effective use for fixing to the bones of all the necessary legs and holes (due to the simulator of the fastener), the reliability of the fastening of all plastic fragments is ensured and the rotational mobility of the graft is excluded.

The invention is illustrated by drawings, where figure 1 shows a fastener with flexible elements on all four legs, figure 2 is a diagram of the use of a fastener.

A bone plastic fastener made in the form of a plate contains an expanded middle part I in the form of a circle, oval, octahedron, etc. with a central hole 2 and off-center 3, legs 4 with holes 5 and flexible elements 6 in the form of a flat spiral spiral with an angle of rotation of the ends by 180 degrees. Like the prototype, the legs form two blunt and two sharp corners located between them.

The bone fastener is made of a metal, for example titanium, plate with a thickness of 0.5-1.0 mm. Sizes of a fastener: length is 35-50 mm, width is 15-20 mm; hole diameter 2.0-2.2 mm - for standard mini-screws.

The fastener is used as follows. An osteotomy of the lower jaw is performed in the required place, fragments of the jaw are moved to a predetermined position. On the bone graft, the middle part I of the fastener is fixed with screws through holes 2 and 3. Then the graft with a fastener is placed between the osteotomized fragments of the jaw and the legs 4 are fixed to two fragments of the jaw with screws through the holes 5. In this case, the legs 4 are bent in different directions to give the fastener the desired shape depending on the relief of the jaw, its curvature, size, etc.

The use of the inventive fastener for bone grafting allows due to the presence of flexible elements on the legs and, as a result, its easy modeling to ensure reliable bonding of all fragments of bone grafting and to exclude rotational mobility of the bone graft.

Claims (1)

A bone plastic fastener made in the form of a metal plate with an expanded middle part and at least three legs, provided with at least four holes in the middle part, including one central, and holes on each of the legs, characterized in that at least one of the legs is equipped with a flexible element in the region between the middle part and the hole closest to it, made in the form of a flat helical spiral with an angle of rotation of 180 °.

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