GB2553372A

GB2553372A - Surgical retractor

Info

Publication number: GB2553372A
Application number: GB1615116.9A
Authority: GB
Inventors: Mcnulty Alan
Original assignee: SHEFFMED TRADE SERVICES Ltd
Current assignee: SHEFFMED TRADE SERVICES Ltd
Priority date: 2016-09-06
Filing date: 2016-09-06
Publication date: 2018-03-07
Also published as: EP3509502A1; GB201615116D0; WO2018046916A1

Abstract

A retractor system for holding tissue out of the way of a surgeon during a surgical procedure. The retractor system is operable to apply forces to tissue in a continuous range of directions and comprises a handle 12, a retaining member 14 that is connectable to the handle such that the retaining member 14 is operable to articulate relative to the handle 12, and a retractor stem 16. The retaining member 14 comprises a plurality of spherical seats 24 and the retractor stem 16 comprises a plurality of spherical stoppers 26 that are arranged to engage the spherical seats 24. The stem 16 includes a tissue engaging portion which may be a hook 30. The retractor may include a clamp to attach to the retaining member 14 and hold the stem 16 in place.

Description

(71) Applicant(s):

Sheffmed Trade Services Limited Unit A, 40 Clifton Street, SHEFFIELD,

South Yorkshire, S9 2QD, United Kingdom (72) Inventor(s):

Alan McNulty (74) Agent and/or Address for Service:

HGF Limited

Document Handling - HGF - (Sheffield), 1 City Walk, LEEDS, LS11 9DX, United Kingdom (51) INT CL:

A61B 17/02 (2006.01) (56) Documents Cited:

US 6013027 A US 5785649 A1

US 3542015 A US 20120035424 A1

US 20030092969 A1 (58) Field of Search:

INT CLA61B

Other: EPODOC & WPI (54) Title of the Invention: Surgical retractor

Abstract Title: Surgical retractor with spherical recesses to engage spherical stoppers on retractor stem (57) A retractor system for holding tissue out of the way of a surgeon during a surgical procedure. The retractor system is operable to apply forces to tissue in a continuous range of directions and comprises a handle 12, a retaining member 14 that is connectable to the handle such that the retaining member 14 is operable to articulate relative to the handle 12, and a retractor stem 16. The retaining member 14 comprises a plurality of spherical seats 24 and the retractor stem 16 comprises a plurality of spherical stoppers 26 that are arranged to engage the spherical seats 24. The stem 16 includes a tissue engaging portion which may be a hook 30. The retractor may include a clamp to attach to the retaining member 14 and hold the stem 16 in place.

At least one drawing originally filed was informal and the print reproduced here is taken from a later filed formal copy.

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Surgical Retractor

TECHNICAL FIELD

The present invention relates to a surgical retractor for maintaining access to a surgical site by holding surrounding tissue away from an area on which a surgeon wishes to operate.

BACKGROUND

During surgical procedures the tissue surrounding a surgical site is often retracted by an assistant who holds the tissue using a surgical hook. Retractor apparatuses configured to retain one or more hooks have also been developed. However, a drawback of such apparatuses is that they are often only operable to apply tension in a limited range of directions, so there may be procedures that they are not suitable for.

It is an object of embodiments of the invention to at least mitigate one or more of the problems of the prior art.

SUMMARY OF THE INVENTION

According to an aspect of the invention for which protection is sought there is provided a surgical retractor system comprising:

a handle;

a retaining member being connectable to the handle such that the retaining member is able to articulate relative to the handle; and a retractor stem, said retractor stem comprising an elongate member having a tissue engaging portion at an end thereof and a plurality of spherical stoppers spaced apart along a length of the elongate member, wherein:

said retaining member comprises a plurality of recesses, each recess defining a spherical seat and being arranged to allow a portion of the retractor stem to pass through the retaining member; and the spherical seats are operable to engage the spherical stoppers, thereby limiting movement of the retractor stem through the retaining member. Such a surgical retractor system may be held in place in the vicinity of a surgical site using an articulated arm. The surgical retractor system can then be used to hold tissue out of the way of a surgeon who requires access to the surgical site by engaging the tissue with the tissue engaging portion of the retractor stem and then fixing the retractor stem to the retaining member by inserting the retractor stem into one of the recesses and allowing a spherical stopper of the retractor stem to engage the spherical seat.

The retaining member may be connectable to the handle via a bolt. The retaining member may be operable to rotate relative to the handle when the bolt is partially loosened and may be substantially fixed relative to the handle when the bolt is tightened.

Providing a spherical stopper on the retractor stem and a spherical seat on the retaining member allows the retractor stem to apply a force to tissue in a continuous range of directions, as the retractor stem is operable to rotate relative to the retaining member about three mutually perpendicular axes.

In an embodiment the surgical retractor system further comprises a clamp, said clamp being attachable to the retaining member, wherein:

the clamp comprises a clamp recess defining a clamp spherical seat;

the clamp recess is arranged such that a portion of the retractor stem is able to pass through the clamp at the clamp recess; and the clamp spherical seat is operable to engage said spherical stoppers, thereby limiting movement of the retractor stem through the clamp. Providing such a clamp may improve the flexibility of the system as it allows the retractor stem to be attached to the retaining member indirectly and from a location that is somewhat distant from the retaining member.

Optionally, at each of said recesses said retractor stem is operable to pass through said retaining member in a direction perpendicular to a first surface, said first surface being a surface ofthe retaining member;

at said clamp recess said retractor stem is operable to pass through said clamp in a direction perpendicular to a second surface, said second surface being a surface ofthe clamp; and when said clamp is attached to said retaining member said first surface is inclined relative to said second surface. Allowing the retractor to pass through the clamp recess in a direction that is inclined relative to the direction in which it can pass through the recess on the retaining member increases the range of directions in which the retractor system can be used to apply forces to tissue.

Further optionally, said first surface may be substantially perpendicular to said second surface when said clamp is attached to said retaining member.

In an embodiment said plurality of recesses may comprise a first recess and a second recess, wherein:

at said first recess said retractor stem is configured to pass through the retaining member in a direction perpendicular to a first surface of the retaining member;

at said second recess said retractor stem is configured to pass through said retaining member in a direction perpendicular to a second surface of the retaining member; and said first surface is inclined relative to said second surface.

Optionally, said retaining member is arcuate. This may allow the retaining member to be positioned such that a plurality of recesses are positioned near to the surgical site, and each of the recesses may be operable to secure a retractor stem in position from a different direction.

The surgical retractor system may comprise a plurality of said retaining members. Two of said retaining members may be simultaneously connectable to the handle. Further optionally, each of the retaining members may comprise a connecting portion, wherein each of said retaining members may be connected to said handle or another of said retaining members at said connecting portions. Each of said retaining members may comprises a plurality of connecting portions. Providing a plurality of retaining members with connecting portions may allow the system to be customised to the requirements of particular surgical procedures.

In an embodiment said plurality of retaining members comprises at least a first retaining member having a first number of recesses and a second retaining member having a second number of recesses, said second number being greater than said first number. Providing different retaining members with different numbers of recesses may allow the system to be customised for the requirements of a particular surgical procedure.

Optionally, said tissue engaging portion comprises a surgical hook. Alternatively, said tissue engaging portion could comprise a retractor. The retractor may be provided with a flat blade for engaging tissue.

The surgical retractor system may further comprise an articulated arm having a holding portion operable to hold said handle. Such an articulated arm may be used to position the surgical retractor system in the vicinity of a surgical site.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will now be described by way of example only, with reference to the accompanying figures, in which:

Figure 1 shows a surgical retractor system in an embodiment of the present invention;

Figure 2 shows another view of the surgical retractor system shown in figure

1;

Figure 3 shows a handle of a surgical retractor system in an embodiment of the present invention;

Figure 4 shows a retaining member of a surgical retractor system in an embodiment of the present invention;

Figure 5 shows a clamp for attaching to a retaining member in an embodiment of the present invention;

Figure 6 shows a cross section through a retaining member and an attached clamp in an embodiment of the present invention; and

Figures 7a and 7b show cross sections at different locations along the length of a retaining member in another embodiment of the present invention.

DETAILED DESCRIPTION

Figure 1 shows a surgical retractor system 10 comprising a handle 12 having a holding portion 34 and being connected to two retaining members 14 at connecting portions 18. Each of the retaining members 14 comprises an arcuate member having a plurality of recesses 20, each recess having an opening 24 and a spherical seat 22. The retractor system 10 also comprises a plurality of retractor stems 16 (of which only one is shown). Each retractor stem comprises an elongate member having a plurality of spherical stoppers 26 disposed along its length, such that a plurality of narrow, cylindrical regions 28 are disposed between adjacent spherical stoppers 26. The retractor stems also comprise a tissue engaging portion 30 at an end thereof. In the illustrated embodiment the tissue engaging portion is a surgical hook, but it will be understood that any type of surgical hook or surgical retractor would be suitable. For example, the tissue engaging portion may comprise Langenbeck retractor, a two pronged retractor or a three pronged retractor.

The surgical retractor system 10 shown in figure 1 can be used to hold tissue surrounding a surgical site out of the way of a surgeon who requires access to the site. The handle 12 and the retaining members 14 connected to the handle are arranged to be held in position near to the surgical site by an articulated arm (not shown) that is arranged to grip the handle 12 at holding portion 34. A suitable articulated arm is produced by GEOMED Medizintechnik GmbH under the trade name ASSISTO®. Tissue surrounding the surgical site may then be retracted by engaging the tissue with the hook 30 of a retractor stem 16 and then fixing the hook and tissue in a desired position by placing the retractor stem into one of the recesses 20 by passing a cylindrical portion of the retractor stem 16 through an opening 24 of one of the recesses 20 and moving the retractor stem through the recess in an axial direction (i.e. along axis C as shown in figure 6) until the spherical stopper 26 above the cylindrical portion engages the spherical seat 22 of the recess 20. It will be understood that it is advantageous for the retractor stem 16 to be in tension when it is fixed relative to the retaining member 14, as this causes the spherical stopper to firmly engage the spherical seat and retains the hook in engagement with the tissue. This substantially prevents further relative movement between the tissue, the retractor stem 16 and the retaining member 14. Tension in the retractor stem is typically maintained by the reaction force of the retracted tissue against the hook 30.

A particular advantage of providing spherical stoppers 26 that are arranged to engage spherical seats 22 is that this allows significant flexibility in the angle at which a force can be applied to tissue by a retractor stem that is held in tension between the tissue and the retaining member 14. This is because the spherical stoppers and spherical seats are able to fix the position of a point on the retractor stem relative to the retaining member whilst allowing significant flexibility in the angular orientation of the retractor stem relative to the retaining member.

Another advantage of the surgical retractor system 10 of embodiments of the present invention is that it allows the location at which the retractor stems 16 are fixed to be varied without repositioning the entire system 10. This is achieved by allowing the retaining members 14 to articulate relative to the handle 14. Figures 3 and 4 show, respectively, a handle 12' and a corresponding retaining member 14', which can be used in embodiments of the present invention. Retaining member 14' can be connected to handle 12' in a manner that permits articulation of the retaining member 14' relative to the handle 12' by inserting raised portion 40 of the retaining member 14' into one of the apertures 44 from the underside of the handle 12' (i.e. in the direction indicated by arrow A). Raised portion 40 is sized so as to produce a clearance fit within the apertures 44. The connection is then completed by inserting a bolt (not shown) having a head that is larger in diameter than the apertures 44 into threaded hole 42. When the bolt is tightened the head of the bolt engages surface 46, and friction between the head of the bolt and surface 46 substantially prevents articulation of the retaining member 14' relative to the handle 12'. If the bolt is loosened then the friction between the head and surface 46 is reduced, and rotation of the retaining member 14' relative to the handle 12' about a central axis of the aperture 44 can be performed. Preferably, the head of the bolt is sufficiently large that it hand tightening can be sufficient to secure the retaining member 14' relative to the handle 12', and the bolt can be loosened by hand to allow articulation of the retaining member 14' relative to the handle 12'.

Allowing the retaining member 14' to rotate relative to the handle 12' provides additional flexibility in the direction from which the surgical retractor system can apply a force to tissue. A surgeon wishing to use the retractor system of the present invention to move a portion of tissue in a particular direction may loosen the bolt holding a retaining member 14' to the handle 12' so that the retaining member can be rotated relative to the handle. The surgeon may then rotate the retaining member until one of the spherical seats 22 lies along or close to a line that starts from the portion of tissue that the surgeon wishes to apply a force to and that is defined in the direction of the required force. The surgeon can then engage the tissue with the tissue engaging portion (e.g. a hook 30) of a retractor stem 16, and then fix the retractor stem in place by inserting one of the spherical stoppers 26 into the aligned spherical seat 22, ensuring that the retractor stem remains in tension when the spherical stopper is inserted into the spherical seat. If the surgeon wishes to vary the magnitude of the force applied to the tissue then they may change the spherical stopper that is inserted into the aligned spherical seat 22. As will be readily understood by the skilled person changing to a spherical stopper that is located closer to the tissue engaging portion without moving the retaining portion 14' will cause the force applied to the tissue to be increased, whereas changing to a spherical stopper that is located further away from the tissue engaging portion without moving the retaining portion 14' will cause the force applied to the tissue to be decreased.

If required, an additional, similar, retaining member may be connected to the retaining member 14' by inserting an upstanding connecting portion 40 into bore 48, and then securing the retaining members together using a bolt similar to the one used to secure the retaining member 14' to the handle 12'. This may allow a surgeon to extend the area in which the retractor system is able to perform tissue retraction. Furthermore, the additional retaining member may be articulated relative to the retaining member that is connected to the handle 12'. This may allow the retractor system to perform tissue retraction for large surgical sites in which covered by a single retaining member could not provide enough spherical seats to provide adequate retraction.

The retaining member 14 shown in figure 4 is provided with eight recesses 20. However, it will be understood that this is merely exemplary, and in some embodiments a different number of recesses may be provided. Indeed, in some embodiments a retractor system may be provided with a plurality of retaining members having different numbers of recesses, thereby allowing a surgeon to select the most appropriate size of retaining member for a particular surgical procedure. This may also allow a surgeon to connect retaining members of different sizes together to produce a retaining member having the required number of recesses, or to produce a retaining member that is articulable at a location where articulation is likely to be advantageous. In some embodiments, different retaining members may have different radii of curvature to each other. This may improve the flexibility of the system.

It will be understood that a retractor stem 16 that has been inserted into one of the recesses 20 so that one of the spherical stoppers of the retractor stem engages one of the spherical seats 22 will be rotatable about three mutually perpendicular axes. The retractor stem will be operable to rotate freely about its longitudinal axis, which allows the direction of the hook 30 to be changed after the spherical stopper is inserted into the spherical seat. The retractor stem 16 will also be operable to rotate about two additional axes that are perpendicular to each other and the longitudinal axis of the retractor stem, although the rotation about the additional axes will be limited to rotation within a particular arc, as the cylindrical regions 28 that are adjacent to the spherical stopper 26 that has been inserted into the retractor stem will engage the retaining member at a certain point in the rotation of the retractor stem 16 about each of the additional axes, thereby preventing further rotation.

Figure 5 shows a clamp 50 that may be connected to a retaining member 14, 14' of a system according to the present invention so as to provide a recess and spherical seat that is perpendicular to the recesses and spherical seats on the retaining member. The clamp 50 comprises a recess 52 that defines a cylindrical seat 54. The recess and cylindrical seat are substantially the same size as the recesses 20 and cylindrical seats 22 that are provided on the retaining members 14, 14' shown in figures 1, 2 and 4. Accordingly, a similar retractor stem 16 may be retained in the clamp 50 by inserting a cylindrical portion 28 of the retractor stem into the recess 52 and then moving the retractor stem through the clamp 50 in an axial direction (i.e. along axis B as shown in figure 6) until the spherical stopper adjacent to the inserted cylindrical portion engages the cylindrical seat 54.

The clamp 50 may be connected to the retaining member 14 by either sliding the retaining member into the partially enclosed region 62 defined between the side walls 58A, 58B, the flanges 56A, 56B and the connecting wall 64, or by inserting the retaining member through the gap between the flanges 56A, 56B. If the retaining member is to be inserted through the gap between the flanges then the side walls 58A, 58B and the connecting wall 64 may be deformed so as to move the flanges 56A, 56B out of the way of the retaining member 14. Once the retaining member 14 is fully inserted into the partially enclosed region 62 the side walls and the connecting wall return to their undeformed positions.

Once the retaining member has been inserted into the partially enclosed region 62 it is held in place within the partially enclosed region by friction between the clamp and the retaining member.

Clamp 50 is also provided with a threaded bore 60, which may be used to screw an extension arm (not shown) onto the clamp.

A cross sectional view showing the clamp 50 attached to the retaining member 14 is shown in figure 6. The inner surfaces of the partially enclosed region 62 engage the outer surfaces of the retaining member 14, so as to produce a friction fit. As shown in figure 6, the recess 52 and the spherical seat 54 of the clamp 50 are substantially perpendicular to the recess 20 and spherical seat 22 of the retaining member 14. This can allow a surgeon to apply forces to tissue in directions that would not be possible using a retractor stem inserted into the recess 20 on the retaining member

14, as the arc through which a retractor stem inserted into the recess 52 (i.e. the recess on the clamp 50) may be rotated in the plane shown in figure 6 is inclined by 90 degrees to the arc through which a retractor stem inserted into the recess 20 could be rotated in the plane shown in figure 6. In some embodiments, a retractor stem inserted into the recess 52 may be rotatable within an arc of at least 90 degrees in the plane shown in figure 6, and a retractor stem inserted into the recess 20 may also be rotatable through an angle of at least 90 degrees in the plane shown in figure 6. This allows the possibility of applying forces in a substantially continuous range of directions, as the directions in which forces can be applied using the a retractor stem inserted into recess 20 at least partially overlap the directions in which forces can be applied by a retractor stem inserted into recess 52.

It will be understood that whilst the clamp 50 is shown in a position that covers one of the recesses 20 in the retaining member 14 in figure 6, it would also be possible to position the clamp in a region between recesses 20 on the retaining member, so that none of the recesses in the retaining member 14 are blocked by the clamp 50. Furthermore, although only one clamp is shown, it will be understood that a plurality of clamps 50 may be attached to a single retaining member 14 depending on the requirements of a particular surgical procedure.

The recesses 20 on the retaining member and the recess 52 on the clamp are provided with frusto-conical surfaces 57, 52 opposing the spherical seats 22, 54. The frusto-conical surfaces 57, 52 allow a retractor stem having a spherical surface engaging one of the spherical seats 22, 54 to articulate relative to the retaining member or the clamp, such that the articulation is only limited when the cylindrical portion of the retractor stem adjacent to the spherical surface comes into contact with the frusto-conical surface. In some embodiments the apex angle defined by the frusto-conical surface may be approximately 120 degrees. This may allow a retractor stem having a spherical surface engaging one of the spherical seats 22, 54 and having its longitudinal axis aligned with the central axis B, C of the spherical seat to rotate through up to 60 degrees about two axes that are perpendicular to each other and the central axis of the spherical seat.

In other embodiments the apex angle defined by the frusto-conical surface may, for example, be between 100 and 140 degrees. It will be understood that the apex angle defined by a frusto-conical surface is the angle that would be defined at the apex of a conical surface extended from the frusto-conical surface.

Figures 7a and 7b show cross sections through a retaining member 14” in another embodiment of the present invention. At the location shown in figure 7a the retaining member has an integrally formed upstanding portion 70 in which a recess 52' defining a spherical seat 54' is defined. Recess 52' allows a retractor stem to pass through the retaining member 14” along a generally horizontal axis. At the location shown in figure 7b the retaining member does not have an upstanding portion. A recess 20' defining a spherical seat 22' is provided in the retaining member 14” at the location shown in figure 7b. The recess 20' allows a retractor stem to pass through the retaining member along a generally vertical axis. A retaining member 14” may alternate between regions having recesses 20' and regions having upstanding portions 70 and recesses 52'. This may allow the possibility of applying forces in a substantially continuous range of directions, as the directions in which forces can be applied using the a retractor stem inserted into recesses 20' at least partially overlap the directions in which forces can be applied by a retractor stem inserted into recesses 52'.

The term “spherical” when used herein to describe stoppers and seats is not intended to require that the stoppers and seats have surfaces that are precisely spherical. Instead, the term “spherical” is merely intended to mean that the surfaces sufficiently close to spherical that the seat and the stopper can be maintained in contact with one another without preventing relative rotation of the seat and the stopper about three mutually perpendicular axes. It will also be understood that the seat and the stopper will typically have surfaces define part spheres, not entire spheres.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings), may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of any foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed. The claims should not be construed to cover merely the foregoing embodiments, but also any embodiments which fall within the scope of the claims.

Claims

1. A surgical retractor system comprising: a handle;

said retaining member comprises a plurality of recesses, each recess defining a spherical seat and being arranged to allow a portion of the retractor stem to pass through the retaining member; and the spherical seats are operable to engage the spherical stoppers, thereby limiting movement of the retractor stem through the retaining member.

2. A surgical retractor system as claimed in claim 1 and further comprising a clamp, said clamp being attachable to the retaining member, wherein:

the clamp comprises a clamp recess defining a clamp spherical seat; the clamp recess is arranged such that a portion of the retractor stem is able to pass through the clamp at the clamp recess; and the clamp spherical seat is operable to engage said spherical stoppers, thereby limiting movement of the retractor stem through the clamp.

3. A surgical retractor system as claimed in claim 2, wherein:

at each of said recesses said retractor stem is operable to pass through said retaining member in a direction perpendicular to a first surface, said first surface being a surface of the retaining member;

at said clamp recess said retractor stem is operable to pass through said clamp in a direction perpendicular to a second surface, said second surface being a surface of the clamp; and when said clamp is attached to said retaining member said first surface is inclined relative to said second surface.

4. A surgical retractor system as claimed in claim 3, wherein said first surface is substantially perpendicular to said second surface when said clamp is attached to said retaining member.

5. A surgical retractor system as claimed in claim 1, wherein said plurality of recesses comprises a first recess and a second recess, wherein:

6. A surgical retractor system as claimed in any preceding claim, wherein said retaining member is arcuate.

7. A surgical retractor system as claimed in any preceding claim and comprising a plurality of said retaining members.

8. A surgical retractor system as claimed in claim 7, wherein each of said retaining members comprises a connecting portion, wherein each of said retaining members may be connected to said handle or another of said retaining members at said connecting portions.

9. A surgical retractor system as claimed in claim 7 or claim 8 wherein said plurality of retaining members comprises at least a first retaining member having a first number of recesses and a second retaining member having a second number of recesses, said second number being greater than said first number.

10. A surgical retractor system as claimed in any preceding claim, wherein said tissue engaging portion comprises a hook.

11. A surgical retractor system as claimed in any one of claims 1-9, wherein said tissue engaging portion comprises a retractor.

12. A surgical retractor system as claimed in any preceding claim and further comprising an articulated arm having a holding portion operable to hold said handle.

13. A surgical retractor system substantially as described herein with reference to the accompanying drawings.

Intellectual

Property

Office

Application No: GB1615116.9 Examiner: Mr Robert Hunt