WO2016080924A1

WO2016080924A1 - Working cannula for wire retainers

Info

Publication number: WO2016080924A1
Application number: PCT/TR2014/000444
Authority: WO
Inventors: Emre KARADENİZ
Original assignee: Karadeni̇z Emre
Priority date: 2014-11-20
Filing date: 2014-11-20
Publication date: 2016-05-26

Abstract

The invention is related to a working cannula which is used for advancing the wire retainers that fasten the Kirschner wire used for compressing and fixing the fractured fragments by being passed through the bones, until the bone surface, without damaging the tissues between the skin and the bone tissue in orthopedic surgery; wherein it comprises a body which allows the wire retainer to advance freely until the bone without damaging the surrounding tissue; a knurled tip which has recesses and protrusions in accordance with the wire retainer; a channel through which the guide passes; and a holding part which is for to manipulate the working cannula.

Description

DESCRIPTION

WORKING CANNULA FOR WIRE RETAINERS TECHNICAL FIELD

The invention is particularly related to a cannula which is used for advancing the wire retainers on kirschner wires. These wire retainers fasten the kirschner wire that is used for compressing and fixing the fractured fragments by being past through the fracture line. This working cannula is to place the wire retainers in desired position until the bone surface, without damaging the tissues between the skin and the bone tissue in orthopedic surgery.

PRIOR ART Techniques developed for fracture treatment until today are Kirschner wire (k-wire), screw, plate screw, intramedularry hail and external fixation. The purpose of these techniques is to fix the fractured fragments in the desired position until healing. The advantages and disadvantages of these techniques change according to the type of fracture and shape the treatment plan of the surgeon.

Among these techniques, in technique of fixation with k-wire, after setting (reducing) the fragments these wires are past through the bone fragments and thus, the broken bones are fixed. After reduction; the broken bones may move forward and backward through the wire since the wires can not provide compression between fragments. Additionally these wires may migrate after being placed into the body.

In fracture fixation with screw, the fragments are first placed into their original places. Compression between the fragments is obtained according to the principle of forming mutual force between the screw head and the screw threads which is the working principle of screw. In this technique it is required to increase the dimensions of the screw to increase the compression force and the adherence. However, if the sizes of the fragments are small, the dimension of the screw can not be increased. Due to the screw size, no space may be left to locate an additional screw between the fragments. Additionally, as a surgical technique, first the bone is drilled with a drill and then, thread holes are opened for screw thread and afterwards, the screw is placed. Additionally, before these processes, sometimes k-wire is needed to be placed to guide the screw. As a result, the surgical technique is relatively complex. Moreover, the compression provided by screw threads may not be enough for patients with osteoporosis.

In fixation of the broken bones with plate and screw, after reducing, the broken fragments are fixed to their locations by plates held by screws. However, since the plates are held by screws, all of the disadvantages of screw technique are also experienced in here. The process of placing plates requires the abrasion of more tissue surrounding the bone. This means more incision and more vascularization problem for the bone pieces. The plate may prevent the healing of skin where the subcutaneous tissue is very thin and may be felt by hand. When the bone pieces are small or very close to the joints, it is impossible to place the plates. Additionally, when they are needed to be taken out, the surrounding tissue is damaged again.

As a result, due to the disadvantages mentioned above and the insufficiency of the present solutions, the product with application no 2010/05662 and title "A wire retainer" is developed different from the known methods. In order to use this "wire retainers" in the fixation of broken bones, the "working cannula" subject to the application is developed.

OBJECTS OF THE INVENTION

The main object of the invention is to present a tool in order to place the "wire retainers" - subject to a patent under examination- into the body during surgery with little damage to the soft tissues. Another object of the invention is to achieve bone healing by giving minimum harm to the bones and the surrounding soft tissue by using the wire retainers with percutaneous techniques.

An object of the invention is^' to provide the fixation after reducing with the help of thin wires by providing compression at the fracture line and to make it possible to compress small fragments. .

An object of the invention is to use the thin k-wires for both compression and support by virtue of a "wire retainer". Another object of the invention is to eliminate the problem of collapsing of small fragments in fractures which are close to the joints such as knees by placing multiple k-wires beneath the fractured fragments. In order to place the screw, thick grooves are opened on the bone pieces. An object of the invention is to eliminate the problem of formation of new fractures due to these thick grooves by the usage of k-wires which are much thinner than these grooves.

Another object of the invention is to provide compression over the k-wire by using the wire with the "wire retainer" according to application number 2010/05662 in cases where the bone anatomy, such as fractures around the elbow, does not allow the usage of thick fixation tools.

Another object of the invention is to carry out the surgery without groove opening, drilling, etc.

The structural and distinctive characteristics and all advantages of the invention will be better understood with the figures below and the detailed description written by referring to these figures; therefore, the invention should be evaluated considering these figures and the detailed explanations.

FIGURES FOR A BETTER UNDERSTANDING OF THE INVENTION

Figure 1 is the overall view of the cannula according to the invention.

Figure 2 is the top view of the holding part of the cannula according to the invention.

Figure 3 is the view of the working cannula according to the invention in usage together with the guide.

DESCRIPTION OF THE REFERENCES

Gu. Guide

R. Retainer

Knurled Tip

2 Channel

3 Body

4 Holding Part 5. Kirschner wire / K-wire

6. Working Cannula

It is not necessary to scale the drawings and the details which are not necessary for a better understanding of the invention may have been omitted. Additionally, the elements which are at least substantially identical or have at least substantially identical functions are shown with the same reference number.

DETAILED DESCRIPTION OF THE INVENTION

In this detailed description, preferred embodiments of the working cannula (6) according to the invention are described only for a better understanding of the subject.

The invention is used together with "A wire retainer" which is subject to the patent application No. 2010/05662 from Turkish Patent Institute under examination and used for fixation of the broken bones. Said working cannula (6) especially provides the usage of the retainer (R) subject to the patent application No. 2010/05662, with percutaneous techniques.

Since the dimension of this "wire holder" is equal to the size of screw heads; the retainer (R) occupies a much smaller space compared to the plates located onto the fragments and the problem of feeling the retainer (R) with hand is experienced rarely. Since the compression force provided by threads in screws requires adherence to the bone marrow; the usage of screw causes difficulties in patients with low bone quality. However, since "a wire retainer" provides holding over the bone cortex, it provides very important usage advantages in patients with low bone quality, such as the patients with osteoporosis. Since cortical adherence is provided with "a wire retainer", the problem of dislocation of retainers (R) is not experienced. While taking the k-wire (5) out after fracture treatment, the damage given to the bone and the surrounding soft tissue is minimized by using "a wire retainer" and the wire may be taken out much more easily by percutaneous techniques with the help of a magnet as it is described in application titled " Magnetic apparatus for wire retainers".

The invention in general comprises;

- The body (3) which ^"allows advancing of the wire retainer (R) freely until the bone surface on k-wire without damaging the surrounding tissue; - a knurled tip (1 ) which peels the bone tissue off the soft tissue thereon, allows advancing of the body (3) without cutting the surrounding tissue, has recesses and protrusions, and is formed in accordance with the wire retainer (R) diameter;

- a channel (2) through which the guide (Gu) advancing over the Kirschner wire (5) passes; and

- a holding part (4) which is for to manipulate the working cannula (6).

The working cannula (6) for the wire retainer is used for allowing the retainer (R) and Kirschner wire (5) subject to the patent titled "A wire retainer" to be located in the desired position properly without damaging the surrounding tissue.

Thanks to the channel (2) in the working cannula (6), a hollow space is provided in order for the retainer (R) to advance until the bone surface. The working cannula (6) passes over the wire retainer guide (Gu) which makes way towards the bone by following the Kirschner wire (5), thanks to the channel (2) inside the body (3) thereof. It advances without cutting the surrounding tissue thanks to the knurled tip (1 ) and peels the bone tissue off the soft tissue thereon. The working cannula (6) protects the hollow space created by the guide (Gu) by its body (3) after the guide (Gu) is removed and it provides a hollow space from the skin to the bone in order for the retainer (R) to be located therein. Manual guiding and rotation are allowed by the holding part (4).

In an alternative embodiment of the invention;

The knurled tip (1 ) of the invention may be sharper, more blunt or straight. The channel (2) disposed in the middle of the invention may have a different diameter and be located eccentrically. The body (3) of the invention may be of a different shape other than cylinder (e.g. hexagonal, rectangular) and a different length. The holding part (4) of the invention may be "T", "L", "C" shaped or may have another shape.

Claims

A working cannula (6) which guides the retainer (R) and the way of which is made by a guide (Gu), in order for the retainers (R) to be advance without damaging the tissues at a distance from the skin until the bone tissue by following the Kirschner wire (5) that is placed between the fragments by being passed through the bone, said retainer being used for fixation of and in the treatment of fractures, characterized in comprising the following within a body (3) which allows the wire retainer (R) to advance until the bone surface without damaging surrounding tissue;

a knurled tip (1 ) which peels the bone tissue off the soft tissue thereon, allows advancing of the body (3) without cutting the surrounding tissue, has recesses and protrusions, and is formed in accordance with the wire retainer (R) diameter;

a channel (2) through which the Kirschner wire (5) and the guide (Gu) pass, said guide making the way towards the bone by following the Kirschner wire (5); and a holding part (4) which manuplates the working cannula (6).