GB2455182A

GB2455182A - Clamp for use in orthopaedic surgery

Info

Publication number: GB2455182A
Application number: GB0820828A
Authority: GB
Inventors: Christian Wohlrab
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-11-16
Filing date: 2008-11-14
Publication date: 2009-06-03
Also published as: GB0820828D0; GB0722562D0

Abstract

A clamping device comprises a gripping portion having first and second elements, each provided with at least one jaw. The jaws are configured to remain substantially parallel relative to each other as the first element is moved towards or away from the second element by an adjustment mechanism. The device may comprise a sliding mechanism 6,8, moved by a bar 3 fixed in between handles 1, 2. The device may be used to clamp bones during orthopaedic surgery. The jaws may be angled, for example, at 90 degrees to the handles, in order to keep the handles out of the way of the surgeon. A locking means may be provided, such as a bar 4 provided with teeth 7, which engage with teeth on one of the handles.

Description

Wrench/bone clamp

Background

A clamp was required which holds the bone in orthopaedic surgery from the sides, with the handle on the side as well.

Most clamps are straight, therefore when the jaws are holding the bone from the side, the handle sticks up and is in the way of the surgeons hands or further instruments.

Conventional clamps, which have angulated jaws as required here, open with a sort of shearing mechanism and/or require adjustment to the thickness of the object they hold. Both would be disadvantageous during surgery.

Statement of invention

In order to overcome the problem above, a sliding mechanism was introduced, keeping the jaws of the clamp nearly parallel at all times.

Advantages No prior adjustment of the clamp/wrench to the size of the object is necessary. The jaws are closing in a virtually parallel fashion on the bone/other object.

Advantages in orthopaedic surgery: Less soft tissue damage: 1. in regard to blood vessels/nerves: e.g. if the clamp needs to be applied to the shin bone just below the knee, the delicate structures (nerve, blood vessels) in the poplitea (back of knee) are not tempered with when applying the clamp, because the bone is held from either side. Conventional clamps with their jaws applied to either side of the bone would have their handles stick straight up, thus being in the way of the surgeons hands and instruments.

If a conventional straight clamp was used, and the handle was to be on the side, one of the jaws would be behind the bone, increasing the risk of damage to nerves/blood vessels behind the bone.

2. in regard to connective tissue/periost (=skin' around the bone): The new clamp requires no removal of the soft tissues/periost behind the bone, herewith less damage to the blood supply of the bone, which will result in faster healing and lower risk of infections.

This means use of this clamp will result in a less traumatic and faster operation.

The clamp with above sliding mechanism may have adaptations of the jaws for minimally invasive surgery as shown below.

Introduction to drawings

There are 5 sheets numbered 1/5 to 5/5.

Figure 1 shows an example of a halfway open clamp.

Figure 2 shows the vertical view of the end of one branch of the handle of the clamp.

Figure 3 shows a horizontal plane view through the end of branch/handle 1, demonstrating the locking mechanism.

Figure 4 shows an example of a closed clamp.

Figure 5 shows an example of the same clamp with a different locking mechanism Figure 6 shows the vertical view of the end of one branch of the handle of the clamp in figure 5.

Figure 7 shows an example of a clamp with same sliding mechanism, but with an adaptation of the jaws for minimally invasive surgery.

Figure 8 shows an example of a clamp with same sliding mechanism and with the jaws adapted for minimally invasive surgery. Here the jaws are removable and are sturdy wires.

Only the upper part of the clamp is shown in figure 8. The handle is same as in the previous drawings.

Detailed description

A wrench (Fig. 1) with a sliding mechanism: a slot (Fig. 1:6) is cut into one branch (Fig. 1:1) of the instrument. A small bolt (Fig. 1:8), attached to branch 2, slides in the slot of branch 1. The bolt has a small head, wider than the slot, which prevents the bolt from slipping out of the slot, and which keeps branch 1 and 2 together.

A short bar (Fig. 1:3) is fixed in between the handles of branches I and 2. It is fixed in a way that it can rotate round pivots 9 and 10 (Fig. 1).

On pressing the handles together, the bar (Fig. 1:3) will move the jaw of branch 2 (Fig. 1) towards the jaw of branch 1 (Fig. 1).

There is a mechanism to lock the wrench once attached to an object. This could be made in various ways. One example demonstrated has a bar (Fig. 1:4) armed with teeth (Fig. 1:7) which engage with teeth at the end of the handle of branch 1 (Fig. I, Fig. 2, Fig. 3).

Another possible locking mechanism is shown in (Fig. 5). Here a short rod (Fig. 5:13) is fixed with a pivot to branch 2 of the wrench. It passes through a slot (Fig. 6:17) in branch 1, and has a screw (Fig 5:14) on the side which is passing through the slot. A nut (Fig 5:15) with wide wings is used to tighten the clamp firmly to the bone or other object.

These locking mechanisms are optional and not new technology.

There might be springs fitted, for to open the wrench (Fig. 4:11), and for to automatically engage the teeth of the locking mechanism with the teeth on handle 1 (Fig. 3:12).

Fig. 4 shows the clamp of Fig. 1 in closed position.

Fig. 7 shows a clamp with same sliding mechanism, but the jaws altered for use in minimally invasive' bone surgeiy.

Fig. 8 shows a clamp with same sliding mechanism, for use in minimally invasive' bone surgery, with the jaws changed to strong wires (Fig. 8:18) (e.g. K-wires, which are frequently being used in orthopaedic surgeiy). The clamp has a mechanism (Fig. 8:19, details not demonstrated, various options possible), with the help of which the wires can be firmly attached to it.

The arrangement in Fig. 8 has the advantage, that bone fragments can be pinned down' with a wire, moved to the right position, and then attached to and held with the clamp.

Claims

Claims 1. A clamping device having: -(i) at least one gripping portion; and (ii) at least one adjustment portion, wherein at least one said gripping portion comprises at least one movable first element and at least one second element, whereby at least one said adjustment portion is adapted to move at least one said first element relative to at least one said second element, wherein said first and second elements each comprise at least one jaw, wherein said jaws are configured so that they remain substantially parallel relative to each other as the first element is moved in a direction either towards or away from the second element
2. A clamping device as claimed in claim 1, wherein said adjustment portion comprises: -(i) a locking part comprising of a plurality of teeth; and (ii) an engagement part adapted to selectively engage with at least one said tooth to substantially retain said first and second elements in position relative to each other
3. A wrench or bone clamp with a sliding mechanism (Fig. 1: 6,8), moved by a bar fixed in between the bandies (Fig. 1:3), holding the jaws in nearly parallel position
4. A wrench or bone clamp, according to claim 1, with jaws adapted for use in minimally invasive bone surgery
5. A wrench or bone clamp, according to claim 1, with removable strong wires, which are part of the jaws.