Support jig for a surgical instrument

Claims

I claim:

1. A jig for consistently maintaining a surgical instrument in a predetermined orientation relative to a subjacent tissue on which the jig is supported, said jig comprising:

a base having a flat surface residing in a first plane for placement in facially engaged relationship with a tissue in the vicinity of where a surgical procedure is to be performed;

an instrument support member;

cooperating means on the base and instrument support member for maintaining the instrument support member in a predetermined position relative to the base and a subjacent tissue on which the jig is supported,

wherein the cooperating means comprises a concave surface on one of the base and instrument support member and a convex surface on the other of the base and instrument support member,

said concave and convex surfaces cooperating with each other to guide universal relative movement between the instrument support member and base; and

means for releasably fixing the convex and concave surfaces in a plurality of different positions relative to each other,

said convex and concave surfaces being fully spaced from the first plane,

whereby the jig can be used to positively maintain a surgical instrument in a desired orientation relative to a subjacent tissue to thereby facilitate the performance of surgical procedures,

wherein the instrument support member has a spherical configuration defining the convex surface and the base has a socket for reception of the instrument support member and defines the concave surface.

2. A jig for consistently maintaining a surgical instrument in a predetermined orientation relative to a subjacent tissue on which the jig is supported, said jig comprising:

a base for placement against a tissue in the vicinity of where a surgical procedure is to be performed;

an instrument support member; and

cooperating means on the base and instrument support member for maintaining the instrument support member in a predetermined position relative to the base and a subjacent tissue on which the jig is supported,

whereby the jig can be used to positively maintain a surgical instrument in a desired orientation relative to a subjacent tissue to thereby facilitate the performance of surgical procedures,

wherein the cooperating means comprises means for selectively maintaining the instrument support member in a plurality of different positions relative to the base,

wherein the cooperating means comprises a concave surface on one of the base and instrument support member and a convex surface on the other of the base and instrument support member, said concave and convex surfaces cooperating with each other to guide universal relative movement between the instrument support member and base,

wherein the instrument support member has a spherical configuration defining the convex surface and the base has a socket for reception of the instrument support member and defines the concave surface,

wherein the instrument support member has sleeve defining a passageway for the introduction of a surgical instrument to be extended into a subjacent tissue on which the jig is supported and the instrument support member has first and second separable parts which when separated facilitate placement of a surgical instrument in the sleeve passageway,

said first and second separable parts cooperatively defining at least a part of said convex surface.

3. A jig for consistently maintaining a surgical instrument in a predetermined orientation relative to a subjacent tissue on which the jig is supported, said jig comprising:

a base for placement against a tissue in the vicinity of where a surgical procedure is to be performed;

an instrument support member; and

cooperating means on the base and instrument support member for maintaining the instrument support member in a predetermined position relative to the base and a subjacent tissue on which the jig is supported,

whereby the jig can be used to positively maintain a surgical instrument in a desired orientation relative to a subjacent tissue to thereby facilitate the performance of surgical procedures,

wherein the cooperating means comprises means for selectively maintaining the instrument support member in a plurality of different positions relative to the base,

wherein the cooperating means comprises a concave surface on one of the base and instrument support member and a convex surface on the other of the base and instrument support member, said concave and convex surfaces cooperating with each other to guide universal relative movement between the instrument support member and base,

wherein the instrument support member has a spherical configuration defining the convex surface and the base has a socket for reception of the instrument support member and defines the concave surface,

wherein the cooperating means includes means for releasably locking the instrument support member selectively in a plurality of different positions relative to the base,

said cooperating means comprising a set screw to engage the convex surface.

4. A jig for consistently maintaining a surgical instrument in a predetermined orientation relative to a subjacent tissue on which the jig is supported, said jig comprising:

a base having a flat surface residing in a first plane for placement in facially engaged relationship with a tissue in the vicinity of where a surgical procedure is to be performed;

an instrument support member;

cooperating means on the base and instrument support member for maintaining the instrument support member in a predetermined position relative to the base and a subjacent tissue on which the jig is supported,

wherein the cooperating means comprises a concave surface on one of the base and instrument support member and a convex surface on the other of the base and instrument support member,

said concave and convex surfaces cooperating with each other to guide universal relative movement between the instrument support member and base; and

means for releasably fixing the convex and concave surfaces in a plurality of different positions relative to each other,

said convex and concave surfaces being fully spaced from the first plane,

whereby the jig can be used to positively maintain a surgical instrument in a desired orientation relative to a subjacent tissue to thereby facilitate the performance of surgical procedures,

wherein the cooperating means comprises means for selectively maintaining the instrument support member in a plurality of different positions relative to the base,

wherein the instrument support member has a sleeve defining a passageway for the introduction of a surgical instrument to be extended into a subjacent tissue on which the jig is supported,

wherein the sleeve has an axial extent and there are means on the instrument support member for releasably fixing the position of the sleeve relative to the base.

5. A jig for consistently maintaining a surgical instrument in a predetermined orientation relative to a subjacent tissue on which the jig is supported, said jig comprising:

a base having a flat surface residing in a first plane for placement in facially engaged relationship with a tissue in the vicinity of where a surgical procedure is to be performed;

an instrument support member; and

cooperating means on the base and instrument support member for maintaining the instrument support member in a predetermined position relative to the base and a subjacent tissue on which the jig is supported,

wherein the cooperating means comprises a concave surface on one of the base and instrument support member and a convex surface on the other of the base and instrument support member,

said concave and convex surfaces cooperating with each other to guide universal relative movement between the instrument support member and base,

said convex and concave surfaces being fully spaced from the first plane,

whereby the jig can be used to positively maintain a surgical instrument in a desired orientation relative to a subjacent tissue to thereby facilitate the performance of surgical procedures,

wherein the instrument support member has a spherical configuration defining the convex surface and the base has a socket for reception of the instrument support member and defines the concave surface,

wherein the base flat surface has an annular configuration and the base includes a conical skirt converging away from the flat base surface,

there being means cooperating between the conical skirt and said socket for maintaining the socket spaced from the plane of the flat surface of the base.

6. A jig for consistently maintaining a surgical instrument in a predetermined orientation relative to a subjacent tissue on which the jig is supported, said jig comprising:

a base having a flat surface, said flat surface having an effective diameter of at least 2 inches facing in a first direction for placement against a flexible tissue in the vicinity of where a surgical procedure is to be performed,

there being no structure projecting from the plane of said flat surface in said first direction;

an instrument support member;

cooperating means on the base and instrument support member for maintaining the instrument support member selectively in a plurality of predetermined positions relative to the base and a subjacent tissue on which the jig is supported,

said cooperating means including a cooperating ball and socket; and

annular means for adhering the flat base surface to a subjacent tissue to stably support the base on a subjacent tissue,

whereby the jig can be used to positively maintain a surgical instrument in a desired orientation relative to a subjacent tissue to thereby facilitate the performance of surgical procedures,

wherein the base has a curved yoke and means are provided for connecting the yoke to the base for movement relative thereto,

wherein the yoke has a curved slot and the instrument support member has a pin that is guided in an arcuate path in the curved yoke slot and means are provided for locking the pin in a desired position along the slot to thereby fix the relative positions of the yoke and the instrument support member.

7. The surgical instrument jig according to claim 6 wherein the yoke has an inverted U-shaped configuration.

8. A jig for consistently maintaining a surgical instrument in a predetermined orientation relative to a subjacent tissue on which the jig is supported, said jig comprising:

a base having a flat downwardly facing surface for placement facially against a tissue in the vicinity of where a surgical procedure is to be performed,

there being no structure on said jig extending downwardly beyond the flat downwardly facing surface on the base;

an instrument support member; and

cooperating means on the base and instrument support member for maintaining the instrument support member in a predetermined position relative to the base and a subjacent tissue on which the jig is supported,

whereby the jig can be used to positively maintain a surgical instrument in a desired orientation relative to a subjacent tissue to thereby facilitate the performance of surgical procedures,

wherein the cooperating means comprises means for selectively maintaining the instrument support member in a plurality of different positions relative to the base,

wherein the base has a curved yoke and the cooperating means comprises a pin and slot connection on the yoke and instrument support member,

wherein the yoke has a curved slot and instrument support member has a pin that is guided in an arcuate path in the curved yoke slot and means are provided for locking the pin in a desired position along the slot to thereby fix the relative positions of the yoke and the instrument support member,

wherein the yoke has an inverted U-shaped configuration,

wherein the base has a first wall with a flat surface for placement against a subjacent tissue and a second wall mounted to the first wall for pivoting movement relative to the first wall abut an axis that is transverse to the plane of the first flat wall surface.

9. A surgical instrument jig for consistently maintaining a surgical instrument in a predetermined orientation relative to a subjacent tissue on which the jig is supported, said jig comprising:

a base for placement against a tissue in the vicinity of where a surgical procedure is to be performed;

an instrument support member; and

cooperating means on the base and instrument support member for maintaining the instrument support member in a predetermined position relative to the base and a subjacent tissue on which the jig is supported,

whereby the jig can be used to positively maintain a surgical instrument in a desired orientation relative to a subjacent tissue to thereby facilitate the performance of surgical procedures,

wherein the cooperating means comprises means for selectively maintaining the instrument support member in a plurality of different positions relative to the base,

wherein the base has a curved yoke and the cooperating means comprises a pin and slot connection on the yoke and instrument support member,

wherein the yoke has a curved slot and the instrument support member has a pin that is guided in an arcuate path in the curved yoke slot and means are provided for locking the pin in a desired position along the slot to thereby fix the relative positions of the yoke and the instrument support member,

wherein the yoke has an inverted U-shaped configuration,

wherein the base has a first wall with a flat surface for placement against a subjacent tissue and a second wall mounted to the first wall for pivoting movement relative to the first wall about an axis that is transverse to the plane of the first flat wall surface,

wherein means are provided for selectively locking the first and second walls against relative movement.

10. A jig for consistently maintaining a surgical instrument in a predetermined orientation relative to a subjacent tissue on which the jig is supported, said jig comprising:

a base having a flat surface residing in a first plane for placement in facially engaged relationship with a tissue in the vicinity of where a surgical procedure is to be performed;

an instrument support member; and

cooperating means on the base and instrument support member for maintaining the instrument support member in a predetermined position relative to the base and a subjacent tissue on which the jig is supported,

wherein the cooperating means comprises a concave surface on one of the base and instrument support member and a convex surface on the other of the base and instrument support member,

said concave and convex surfaces cooperating with each other to guide universal relative movement between the instrument support member and base,

said convex and concave surfaces being fully spaced from the first plane,

whereby the jig can be used to positively maintain a surgical instrument in a desired orientation relative to a subjacent tissue to thereby facilitate the performance of surgical procedures,

wherein the cooperating means comprises means for selectively maintaining the instrument support member in a plurality of different positions relative to the base,

wherein the base has a curved yoke and the cooperating means comprises a pin and slot connection on the yoke and instrument support member,

wherein the yoke has a curved slot and the instrument support member has a pin that is guided in an arcuate path in the curved yoke slot and means are provided for locking the pin in a desired position along the slot to thereby fix the relative positions of the yoke and the instrument support member,

wherein the yoke has an inverted U-shaped configuration,

wherein the base has a first wall with a flat surface for placement against a subjacent tissue and a second wall mounted to the first wall for movement relative to the first wall in a path generally parallel to the plane of the first flat wall surface.

11. A jig for allowing consistent placement of a surgical instrument in a predetermined orientation relative to a subjacent tissue on which the jig is supported, said jig comprising:

a base having a first part with a planar surface for placement facially against a tissue in the vicinity of where a surgical procedure is to be performed,

a yoke;

a second base part having means for supporting said yoke;

means interconnecting the first and second base parts for allowing pivoting of the second base part and yoke relative to the first base part about an axis that is substantially at right angles to the plane of the planar surface on the first base part;

an instrument support member on the yoke having a sleeve defining a passageway for the introduction of a surgical instrument to be extended into the tissue;

means for mounting the sleeve to the yoke for movement relative to the yoke in an arcuate path which is in a plane that is transverse to the plane of the planar surface on the first base part; and

means for maintaining the sleeve in a plurality of selected positions relative to the yoke,

whereby with the base placed against a subjacent tissue, an instrument on the instrument support member can be consistently directed through the sleeve passageway against the tissue in a consistent orientation.

12. The jig for orienting a surgical instrument according to claim 11 wherein means are provided for releasably holding the first jig base part in a fixed position relative to a subjacent tissue.

13. The jig for orienting a surgical instrument according to claim 11 wherein said instrument support member has means thereon for captively embracing a tissue through which the sleeve is extended.

14. A jig for consistently orienting a surgical instrument in a predetermined orientation relative to a subjacent tissue on which the jig is supported, said jig comprising:

a first base for placement against a tissue in the vicinity of where a surgical procedure is to be performed,

said base having a yoke;

an instrument support member on the yoke having a sleeve defining a passageway for the introduction of a surgical instrument to be extended into the tissue;

means for supporting the yoke on the base for movement relative to the base; and

means for maintaining the yoke in a plurality of selected positions relative to the base,

whereby with the base placed against a subjacent tissue, the yoke can be fixed in a preselected position, whereupon an instrument can be consistently directed through the sleeve passageway against the tissue in a consistent orientation

wherein said instrument support member has means thereon for captively embracing a tissue through which the sleeve is extended,

wherein the instrument support member sleeve has proximal and distal ends, the means for captively embracing a tissue comprises an expandable member which is positionable selectively in expanded and collapsed states at the distal end of the sleeve and a collar mounted to the sleeve for sliding movement selectively towards and away from the expandable member, whereby the sleeve with the expandable member in its collapsed state can be directed through an incision in a tissue after which the expandable member can be placed in its expanded state and the collar slid along the sleeve to captively embrace the tissue in conjunction with the expandable member in its expanded state.

15. A jig for consistently orientating a surgical instrument in a predetermined orientation relative to a subjacent tissue on which the jig is supported, said jig comprising:

a base for placement against a tissue in the vicinity of where a surgical procedure is to be performed,

said base having a yoke;

an instrument support member on the yoke having a sleeve defining a passageway for the introduction of a surgical instrument to be extended into the tissue;

means for supporting the yoke on the base for movement relative to the base; and

means for maintaining the yoke in a plurality of selected positions relative to the base,

whereby with the base placed against a subjacent tissue, the yoke can be fixed in a preselected position, whereupon an instrument can be directed through the sleeve passageway against the tissue in a consistent orientation,

wherein said yoke comprises cooperating U-shaped elements each with a body and first and second legs projecting from the body with each said leg having a free end, and means are provided for pivotably attaching the free ends of each of the legs of the yoke elements to the base so that the bodies of the U-shaped elements are pivotable selectively towards and away from each other.

16. The jig for orientating a surgical instrument according to claim 15 wherein means are provided for biasing at least one of the U-shaped elements towards the other of the U-shaped elements to thereby captively engage the instrument support member.

17. The jig for orienting a surgical instrument according to claim 16 wherein means are provided for holding the sleeve in a fixed position with respect to at least one of the U-shaped elements.

18. The jig for orienting a surgical instrument according to claim 15 wherein each U-shaped element pivots relative to the base about an axis and the pivot axes for the U-shaped elements are coincident.

19. The jig for orienting a surgical instrument according to claim 15 wherein each U-shaped element pivots relative to the base about an axis and the pivot axes for the U-shaped elements are substantially parallel to and spaced from each other.

20. A jig for consistently maintaining a surgical instrument in a predetermined orientation relative to a subjacent tissue on which the jig is supported, said jig comprising:

a base having a flat surface, said flat surface having an effective diameter of at least 2 inches facing in a first direction for placement against a flexible tissue in the vicinity of where a surgical procedure is to be performed,

there being no structure projecting from the plane of said flat surface in said first direction;

an instrument support member;

cooperating means on the base and instrument support member for maintaining the instrument support member selectively in a plurality of predetermined positions relative to the base and a subjacent tissue on which the jig is supported,

said cooperating means including a cooperating ball and socket; and

annular means for adhering the flat base surface to a subjacent tissue to stably support the base on a subjacent tissue,

whereby the jig can be used to positively maintain a surgical instrument in a desired orientation relative to a subjacent tissue to thereby facilitate the performance of surgical procedures.

21. The surgical instrument jig according to claim 20 wherein the base has a curved yoke and means are provided for connecting the yoke to the base for movement relative thereto.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to surgical procedures, such as laparoscopy, and, more particularly, to a jig for consistently guiding introduction of laparoscopic surgical instruments through a tissue in any of a number of preselected orientations.

2. Background Art

Laparoscopic surgery is a widely accepted alternative to conventional surgery. A principal advantage of laparoscopic surgery is that it generally requires only small incisions in the body tissue, thereby permitting the performance of many major surgical operations on an out-patient basis.

The inventor herein has obtained numerous U.S. patents covering instruments particularly adaptable for use in laparoscopic surgery. Among these are U.S. Pat. No. 4,935,006, entitled "Suction and Irrigation Device" and U.S. Pat. No. 4,944,741, entitled "Laparoscopic Instrument With Pivotable Support Arm".

It should be understood that laparoscopy, as used throughout this specification, is intended in a generic sense to include other surgical procedures, such as endoscopy, etc. which, from a mechanical standpoint, are performed in a similar manner.

The basic laparoscopic instrument consists of an elongate, hollow sleeve with proximal and distal ends, the latter of which is directed through body tissue and into a cavity in which the surgical procedure is to be performed. To facilitate insertion, a spike/trocar is directed through the sleeve and, when fully inserted therein, has a protruding, sharpened point at the distal sleeve end. After a small incision is made in the tissue, the sleeve, with the spike/trocar directed fully thereinto, is forced through the incision.

The inventor herein has devised structure for holding the sleeve in a relatively stable position with respect to tissue through which it extends to thereby facilitate instrument removal and introduction without disturbing the alignment of the sleeve. One such structure is shown in U.S. patent application Ser. No. 334,452, entitled "Laparoscopic Cannula". That device has a sleeve and a membrane thereon which is expandable once the distal end is projected into the body cavity and a slidable collar on the sleeve which, in conjunction with the membrane, positively captures the tissue wall. The collar has a tapered surface which depresses the tissue around the sleeve to provide a relatively airtight seal around the incision. This seal is required to maintain in the cavity CO.sub.2 gas or other gas that may be utilized to distend the cavity to facilitate performance of the surgical procedure. The tapered surface on the collar permits the angle of the sleeve axis to be changed with respect to the tissue without compromising the seal.

One problem with the above described device is that, while the sleeve is positively held in place on the tissue and the integrity of the seal maintained throughout a range of movement of the sleeve, that structure does not permit the sleeve to be selectively reoriented and maintained in the reoriented state. For example, if the sleeve is introduced at one location through the abdominal wall, the curvature of the abdominal wall, when distended, will naturally hold the sleeve in a first orientation. While the sleeve may be manually reoriented by the surgeon, the sleeve naturally tends back towards a centered position. It is difficult, if not impossible, for the surgeon to access a different area in the body cavity, and maintain that position of the sleeve, as to insert different instruments. As a result, it may instead be necessary to provide a separate incision, which is obviously undesirable if the second site is accessible through the first incision.

A further problem with the above system is that, regardless of how securely the sleeve is held relative to the tissue wall, the sleeve tends to float freely around the incision site due to the fact that the tissue wall itself is flexible. Upon the introduction of the instrument, the surgeon may be required to search each time for the exact location at which the operation is being performed.

SUMMARY OF THE INVENTION

The present invention is specifically directed to overcoming the above enumerated problems in a novel and simple manner.

The present invention is directed to a jig for consistently maintaining a surgical instrument in a predetermined orientation relative to a subjacent tissue on which the jig is supported. The jig consists of a base for placement against the tissue in the vicinity of where the surgical procedure is to be performed, an instrument support member, and cooperating structure on the base and instrument support member for maintaining the instrument support member in a predetermined position relative to the base and a subjacent tissue on which the jig is supported.

The present invention allows the surgeon to pre-position the jig, after which different instruments can be directed consistently to the same location in the body cavity. This avoids the surgeons' having to search for the exact site of the surgery each time a new instrument is introduced. At the same time, the jig stabilizes the position of the instrument associated therewith.

In a preferred form, the cooperating structure on the base and the instrument support member is used to selectively maintain the instrument support member in a plurality of different positions relative to the base.

It is possible with the inventive structure for the surgeon to adjust the location of the instrument and, once this is achieved, to lock the jig in an orientation which fixes the desired position of the instrument.

Preferably, the instrument support member has a sleeve defining a passageway for the introduction of a surgical instrument.

In a preferred form, the cooperating structure on the instrument support member and base is a concave surface on one of the base and instrument support member and a convex surface on the other of the base and instrument support member, which surfaces cooperate with each other to guide universal relative movement between the instrument support member and base. Preferably, the instrument support member has a spherical configuration defining a convex surface and the base has a socket for reception of the instrument support member and defines a concave surface.

In one form of the invention, the instrument support member defines a sleeve and is defined at least in part by first and second removably separable parts. With the first and second parts separated, placement of the surgical instrument in its operative position is facilitated.

In a preferred form, there is locking structure for fixing the positions of both the instrument support member relative to the base and the sleeve/instrument relative to the instrument support member.

Preferably, the base has a flat wall surface for placement directly against the subjacent tissue. In one form, the socket for the spherically-shaped instrument support member is spaced from the plane of the flat annular wall surface of the base.

In one form of the invention, the base has a curved yoke and the cooperating structure on the base and instrument support member is a pin and slot connection. Preferably, the yoke has a curved slot and the instrument support member has a guide element, such as a pin, that is guided in an arcuate path in the curved yoke slot. The pin can be locked in a desired position relative to the yoke to thereby fix the relative positions of the yoke and instrument support member. The yoke is preferably U-shaped and may open upwardly or downwardly.

In one form of the invention, the base has a first wall with a flat surface for placement against a subjacent tissue and a second wall mounted to the first wall for pivoting movement relative to the first wall about an axis that is transverse to the plane of the first flat wall surface. In a preferred form, there are structures for selectively locking the first and second walls against relative movement. The yoke is preferably attached to one of the walls.

To add rigidity to the underlying tissue and to prevent shifting of the jig, the jig base is preferably releasably adhered to the subjacent tissue as by an adhesive pad.

The invention also contemplates a jig consisting of a base for placement against a tissue in the vicinity of where a surgical procedure is to be performed, a yoke, an instrument support member on the yoke and defining a passageway for the introduction of a surgical instrument to be extended into the tissue, structure for supporting the yoke on the base for movement relative to the base, and structure for maintaining the yoke in a plurality of selected positions relative to the base.

In a preferred form, the instrument support member is mounted to the yoke for movement relative thereto while the yoke is in turn pivotably connected to the base for rotation about an axis.

Structure is provided for captively embracing a tissue through which the sleeve is extended. In a preferred form, the instrument support member defines a sleeve having proximal and distal ends and the cooperating structure for embracing the tissue is an expandable member which is positionable selectively in expanded and collapsed states at a distal end of the sleeve and a collar mounted to the sleeve for sliding movement selectively towards and away from the expandable member. With the expandable member in its collapsed state, the sleeve can be directed through an incision in a tissue after which the expandable member can be placed in its expanded state and the collar slid along the sleeve to captively embrace the tissue in conjunction with the expandable member.

In one form, the yoke consists of cooperating, U-shaped elements, each with spaced free ends, and a base, with the free ends of the elements pivotably attached to the base so that the ends of the U-shaped elements are in adjacent relationship on the base and so that the U-shaped elements are pivotable selectively towards and away from each other.

In one form, at least one of the U-shaped elements is biased towards the other to captively engage the instrument support member, which preferably can be fixed with respect to at least one of the U-shaped elements.

The pivot axes for the U-shaped elements may be either coincident or in parallel and spaced relationship.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a jig for holding a surgical instrument according to the present invention and showing a surgical instrument operatively associated therewith and extending through the tissue on which the jig is supported;

FIG. 2 is a cross-sectional view of the jig and tissue of FIG. 1;

FIG. 3 is a perspective view of a modified form of jig according to the present invention with a surgical instrument operatively associated therewith and extending through an underlying tissue;

FIG. 4 is a cross-sectional view of the jig and tissue of FIG. 3;

FIG. 5 is a side elevation view of an instrument support member on the jig of FIGS. 3 and 4;

FIG. 6 is a perspective view of one of two joinable halves defining the instrument support member of FIG. 5;

FIG. 7 is a cross-sectional view of the instrument support member taken along line 7--7 of FIG. 5;

FIG. 8 is a perspective view of a further modified form of jig for holding a surgical instrument according to the present invention and having a surgical instrument operatively associated therewith and extending through a subjacent tissue;

FIG. 9 is a cross-sectional view of a still further modified form of jig according to the present invention operatively associated with a surgical instrument extending through underlying tissue;

FIG. 10 is an enlarged cross-sectional view of the connection between a movable yoke and base taken along line 10--10 of FIG. 9; and

FIG. 11 is a view similar to that in FIG. 10 and showing a modified form of connection between the yoke and base.

DETAILED DESCRIPTION OF THE DRAWINGS

In FIGS. 1 and 2, a preferred form of surgical jig, according to the present invention, is shown at 10. The surgical jig 10 is designed to be supported on the outer surface 11 of underlying tissue 12, which bounds a body cavity 14 within which a surgical procedure is to be performed. The jig 10 consists of a base 16 on which an instrument support member 18 is mounted. The instrument support member 18 holds an instrument 20, shown schematically in FIG. 1. A wide range of different types of instruments 20 can be used to perform different laparoscopic procedures. A precise description of these instruments 20 is unnecessary to understand the present invention and is, therefore, omitted herefrom.

The base 16 has a first wall/wall part 22, which is annular and defin