GB2382306A

GB2382306A - A clamp for simultaneously clamping both a clamp support bar and a surgical retractor into position

Info

Publication number: GB2382306A
Application number: GB0221869A
Authority: GB
Inventors: Bernard Joseph Maughan
Original assignee: CLS MEDICAL Ltd
Current assignee: CLS MEDICAL Ltd
Priority date: 2001-09-27
Filing date: 2002-09-20
Publication date: 2003-05-28
Anticipated expiration: 2022-09-20
Also published as: GB0221869D0; GB2382306B; GB0123240D0

Abstract

The clamp comprises a first element 1 for mounting the clamp to a support bar or arm 30, a second element 9 for receiving and clamping the shank 31 of a retractor blade, the two clamping elements are linked and clamped together by a coupling mechanism consisting of shaft element 16, adjustment nut 18 and cam lever mechanism 29, 25 and 28. The cam lever 28 upon movement to the clamping position, simultaneously secures the clamp to both the clamp support bar 30 and the retractor shank 31 against a compressive spring action. Said spring action is provided by elastic deformation allowed by narrow slits or kerfs 5, 15 in the body of said first and second elements 1 and 9. Relative rotation of the clamped parts 30 and 31 is inhibited by providing an anti rotation clutch mechanism formed by matching conical male 10 and female 7 portions of elements 9 and 1, respectively.

Description

Title of the Invention Surgical Retractor Beam Clamp Field of the Invention This invention relates to a surgical retractor beam clamp for use in securing a surgical retractor to a support framework.

Background of the Invention Surgical retractors are known devices used during surgical procedures to separate and withdraw the edges of incised wounds, allowing the surgeon unimpeded access to tissues and organs within the patient's body.

Retractor systems generally comprise one or more support posts which may be secured to the support rail of an operating table, and one or more support arms or bars which may be clamped in position over the area of the patient's body where surgery is to be performed.

Retractors, which typically comprise of a suitably shaped blade or spatula section which will contact the wound edge, affixed to a support shank, must be capable of firm attachment to the support arms or bars in order that the force required to retract the wound edge may be applied and maintained through the support arms and posts.

It is necessary that the means of attachment be capable of rapid and easy fitting to the support arms and the retractor shank, be capable of positional adjustment, both linear and rotational, in all dimensional axes and, upon clamping, provide a firm and positive clamping force, resistant to forces imposed by the retraction process, or other imposed forces.

It is desirable that the clamping devices be of minimum possible weight, be compact, and the means of clamping and release be simple and convenient for surgeons and other theatre personnel to perform.

Object of the Invention The object of the invention is the provision of an improved surgical retractor beam clamp.

Summary of the Invention According to the present invention, there is provided a surgical retractor beam clamp comprising a first element for mounting the clamp to a support arm or bar, a second element for receiving and clamping the shank of a retractor blade, the two clamping elements being axially attached to one another via a rotary coupling mechanism, whilst an operating lever, upon movement to the clamping position, simultaneously secures the clamp to both the support arm or bar, and to the retractor shank against a compressive spring action within the first and second elements, and means to adjust and pre-set the applied clamping force.

Preferred or Optional Features The rotary coupling incorporates an anti-rotation clutch mechanism.

The operation of the lever also engages the clutch mechanism to resist any relative motion between the clamped parts The second clamping element comprises a through hole to receive a shank of a retractor, and is provided with at least one kerf parallel to the through hole and

passing partially through the element.

Two spaced-apart kerfs are provided, cut into opposite sides of the second clamping element.

Brief Description of the Drawings A specific embodiment of the present invention is described herewith with reference to the accompanying drawings, in which: Figure 1 is a perspective view of the first element alone ; Figure 2 is a perspective view of the rotary coupling mechanism alone ; Figure 3 is a perspective view of the second element alone ; Figure 4 is a perspective view of the operating lever, and Figure 5 is an exploded view of an assembly of the elements of Figures 1 to 4 with a retraction blade and also a support arm illustrated.

Detailed Description of the Drawings Figure 1 illustrates a first element of the clamp which element is a lower clamping block 1 comprising a suitably sized piece of appropriate, corrosion resistant material, heat treated as necessary, and incorporating a tapered aperture 2 at the front of the block 1 into which a support bar 30 (Figure 5) or arm may be readily pressed, until it seats in the circular bore 3. A further circular, or otherwise, shaped bore 4 is joined to the bore 3 by means of a slot 5 providing a resilient, spring action around the rear periphery of the lower clamping block 1, thereby allowing the legs of the taper aperture 2 to spring apart and accept insertion of the support bar 30.

A vertical clearance hole 7 from the bottom to the top of the lower clamping block

1, passing between bores 3 and 4 and across the slot 5 accommodates a lower part 17 of a clamping shaft 20 (Figure 3).

A tapered bore 8 extending inwardly from an upper surface of the lower clamping block 1, co-axial with the clearance hole 7 is formed to provide the female element of an anti-rotation clutch in the form of a conical clutch mechanism.

Figure 2 illustrates a second element in the form of an upper clamping thimble 9 the outer, lower section of which comprises a male tapered portion 10 of identical taper to the female bore 8 in the lower clamp block 1, which portion 10 provides the male element of the conical clutch mechanism.

A through bore 11 of a diameter equal to a retractor shank 31 to be clamped by the clamp is provided through, and across, the diameter of the upper clamping thimble 9, and a lozenge shaped pocket 12 is arranged perpendicularly to the through bore 11 within the body of the upper clamping thimble 9 to accommodate a yoke section 21 of a clamping shaft 16 (Figure 3). An axial round through bore (not visible) is formed from the bottom of the pocket 12 as far as the bottom tapered portion 10.

A pair of parallel, narrow slits or kerfs 14 formed parallel to the through bore 11 pass partly, but not completely, through the upper clamping thimble 9, the section of material between the kerfs 15 forming a spring beam allowing the retractor shank 31 placed in the through bore 11 to be clamped securely upon application of an axial, compressive clamping force through the upper clamping thimble 9.

As shown in Figure 3 the clamping shaft 16 has a lower, parallel threaded section 17 upon which an adjustment nut 18 is fitted to adjust and pre-set the clamping force, and when set in the required position, is locked by means of a radial set screw 19, or other means, within the body of the nut 18.

Above the threaded section 17 is a short, plain cylindrical section 20 of suitable diameter to pass within the through bore (not visible) in the lower part of the upper clamping thimble 9.

Above the cylindrical section 20 is the yoke section 21 of lozenge shaped cross section corresponding to that of that pocket 12 in the thimble 9 with an elongated through hole 22 of sufficient width to clear an inserted retractor shank 31 and of sufficient length to permit the clamping shaft 16 to move vertically between its clamped and undamped positions without contacting an inserted retractor shank 31.

At the top of the clamping shaft 16 is a parallel section 23 with a cross hole 24 to accommodate a pin 29 of an actuating handle 28 (Figure 4).

Figure 4 also illustrates a thrust washer 25 in which a suitably profiled seat 26 is provided to engage an over-centre cam profile 27 of an actuating lever 28 which is secured to the clamping shaft 16 by means of the pin 29.

Figure 5 shows an exploded view of all components of the surgical retractor beam clamp.

Operation of the clamp would typically be as follows : The operator ensures that the actuating lever 28 is in the released position, then fits the lower clamping block 1 to a previously positioned support arm or bar. A suitable retractor is selected and its shank passed through the bore 11 in the upper thimble clamp 9.

The clamp in accordance with the invention and the retractor are suitably positioned, and the wound edge is engaged with the retractor blade and pulled to the required degree of retraction.

The actuating handle 28 is moved to the clamping position which, because of the

cam action, will cause the clamping shaft 16 to experience tensile force, the adjustment nut 18 pulling the lower clamping block 1 together, trapping and clamping the support beam 30, or arm. At the same time, the tensile force in the clamping shaft 16 will axially compress the upper clamping thimble 9 securely gripping the retractor shank 31, and the conical clutch sections (bore 8 and portion 10 of the thimble 16) of the lower clamping block 1 and the bore 8 of the upper clamping thimble 9, will be pulled into close engagement, inhibiting axial twisting of the two clamping components 1,9.

Upon movement of the operating lever 28 to the open position, the tensile force within the clamping shaft 16 is relaxed, allowing the retractor shank 31 to be withdrawn or repositioned, and the clamp removed from or repositioned on the support bar 30. The anti-rotation clutch is disengaged, permitting the clamp to be rotated to a different position, if required.

Claims

CLAIMS 1. A surgical retractor beam clamp comprising a first element for mounting the clamp to a support arm or bar, a second element for receiving and clamping the shank of a retractor blade, the two clamping elements being axially attached to one another via a rotary coupling mechanism, whilst an operating lever, upon movement to the clamping position, simultaneously secures the clamp to both the support arm or bar, and to the retractor shank against a compressive spring action within the first and second elements, and means to adjust and pre-set the applied clamping force.
2. A clamp as claimed in Claim 1, wherein the rotary coupling incorporates an anti- rotation clutch mechanism.
3. A clamp as claimed in Claim 1 or Claim 2, wherein the operation of the lever also engages the clutch mechanism to resist any relative motion between the clamped parts.
4. A clamp as claimed in any preceding claim, wherein the second clamping element comprises a through hole to receive a shank of a retractor, and is provided with at least one kerf parallel to the through hole and passing partially through the element.
5. A clamp as claimed in Claim 4, wherein two spaced-apart kerfs are provided, cut

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into opposite sides of the second clamping element.
6. A surgical retractor beam clamp substantially as herein before described with reference to the accompanying drawings.