Retractor For Hip Joint Surgery

Abstract

Surgical apparatus for separating the femur from the acetabulum, such as in total hip joint replacement by the Southern Approach, takes the form of an inverse pair of tongs which open when the handles are closed. More particularly, the free ends of the tongs respectively carry a pin and a hook which extend in a generally orthogonal direction relative to their respective tong arms and the plane of movement therebetween, while the bight of the hook extends away from its arm.

Description

This invention concerns surgical apparatus and more particularly such apparatus for use in part or total hip joint replacement by way of the so-called Southern or Posterior approach.

This approach is advantageous in affording good exposure of and access to the acetabular cavity, but difficulty can sometimes arise in effecting the required separation of the femur and acetabulum. In any case, it is normal for the surgeon to employ an assistant simply to maintain this separation during operation.

An object of the invention is to reduce this difficulty and, to this end, there is provided surgical apparatus for separation of the femur and acetabulum during the Southern approach, which apparatus comprises a pair of elongate members coupled together for mutual separating and closing movement of one pair of corresponding free ends thereof, a pin extending from one of said ends in a direction generally transverse to that of said movement and also to the longitudinal direction of the respective one of said members, and a hook extending from the other one of said free ends in a generally corresponding direction to that of said pin and with the bight of said hook facing generally outwardly from the respective one of said members.

The coupling of said members can be such that the members are conveniently of a pivotal form at corresponding intermediate portions of the members such that the other corresponding ends can serve as handles. In this case it is preferred that at least one of said members is of a bent configuration coupled so that closure of the handles opens the pin and hook carrying ends.

Whatever the coupling arrangement, it is preferred that the pin has an intermediate cranked portion which extends laterally relative to the respective elongate member and away from the other such member.

Similarly, it is preferred that the apparatus comprise a locking or biassing member co-operable with said elongate members to hold said pin and hook separated.

In order to clarify the form of such apparatus, one embodiment thereof is diagrammatically illustrated, by way of example, in the accompanying drawings.

The illustrated embodiment comprises two elongated members 10 and 11 which are curved in a similar manner and coupled at 12 for mutual pivotal rotation about a fixed axis 13 perpendicular to the plane defined by the members. This assembly is such that closure of one pair of corresponding ends of the members, which serve as handles 14, causes mutual opening of the other corresponding ends. One of these other ends carries a pin 15 and the other a hook 16, which pin and hook extend from their respective members 10 and 11 in corresponding directions substantially parallel to the axis of rotation of the members. The bight of the hook faces outwardly from its member 11, and the pin is formed with an intermediate cranked portion 17 which extends laterally relative to its member 10 and in the direction away from the member 11.

In use of this embodiment, the pin is pushed into the ischium behind the sciatic nerve, the nerve being eased to one side for this purpose and thereafter released to accommodate itself in the cranked portion of the pin. The hook is engaged in the surface of the femoral neck. These engagements are effected with the handles open, and are such that subsequent closure of the handles separates the femur from the acetabulum while rotating the femur to expose the femoral head. When this retraction is attained, it can be maintained by holding the handles closed with a simple slotted member or bracket such as indicated at 18.

The embodiment as illustrated will be handed relative to the hip joint with which it is usable if the pin and hook are permanently connected or integrally formed with their respective members. However, interchangeable pin and hook arrangements can be provided so that a single embodiment is usable for left or right hand hip joint retraction.

Also, it is not essential that the members of the apparatus pivot in an inverse manner compared to conventional pliers or tongs. However, if the handles and the other ends open and close together, it may be preferred to employ a spring to bias the apparatus towards a normally open condition so that manual control of the retraction procedure is facilitated, it being easier to grip around the handles and control by squeezing than an opposite action.

Claims

We claim:

1. A surgical apparatus for separation of the femur and acetabulum comprising a pair of elongated members pivotally connected to one another so that one pair of ends thereof can be opened and separated with respect to one another, a pin adapted for piercing the acetabulum attached to and extending from one end of one of said elongated members in a direction transverse to that of said movement and to the longitudinal direction of the member from which it extends, and a hook adapted for embracing the femoral bone connected to and extending from the companion end of the other elongated member in the same direction as said pin, said hook having a bight which opens away from said pin, and means cooperating with said elongated members for holding said ends having said pin and hook separated.

2. Apparatus according to claim 1 wherein said members are pivotally coupled at corresponding intermediate portions therealong to provide another pair of corresponding free ends which serve as handles.

3. Apparatus according to claim 2 wherein at least one of said members is of a bent configuration coupled to the other one of said members so that closure of said handles separates said ends having said pin and hook.

4. The apparatus of claim 1 wherein said means for holding said ends having said pin and hook separated is a latching member.

5. A surgical apparatus for separation of the femur and acetabulum comprising a pair of elongated members pivotally connected to one another so that one pair of ends thereof can be opened and separated with respect to one another, a pin adapted for piercing the acetabulum attached to and extending from one end of one of said elongated members in a direction transverse to that of said movement and to the longitudinal direction of the member from which it extends, said pin having an intermediate generally U-shaped cranked portion adapted to accomodate a sciatic nerve and which extends laterally relative to the respective one of said members and away from the other of said members, a hook adapted for embracing the femur bone attached to and extending from the companion end of the other elongated member in the same direction as said pin, said hook having a bight which opens away from said pin, and means cooperating with said elongated members for holding said ends having said pin and hook separated.

6. The use of a surgical apparatus of the type including a pair of elongated members pivotally connected to one another so that one pair of ends thereof can be opened and separated with respect to one another, an acetabulum bone-piercing pin attached to and extending from one end of one of the elongated members in a direction transverse to the direction of movement of said members and to the longitudinal direction of the member from which the pin extends, and a femoral bone embracing hook attached to and extending from the companion end of the other elongated member in the same direction as said pin, said hook having a bight which opens away from said pin, the use comprising the steps of inserting said pin into the acetabulum, positioning said hook about the femur and separating said acetabulum and said femur by separating said ends having said pin and said hook from one another.

7. The method of claim 6 further comprising the step of positioning the sciatic nerve in a cranked portion of said pin.