WO2010053994A1

WO2010053994A1 - Joint exposure device

Info

Publication number: WO2010053994A1
Application number: PCT/US2009/063283
Authority: WO
Inventors: Jr. Edwin E. Spencer; John M. Fenlin; Brent A. Ponce; Steve Block; Ryan Koepke
Original assignee: Tornier, Inc.
Priority date: 2008-11-04
Filing date: 2009-11-04
Publication date: 2010-05-14
Also published as: WO2010065233A1; FR2945436A1; WO2010017307A1

Abstract

A surgical instrument for shoulder joint distraction includes a scapular arm having a first end and a second end, a humeral arm having a first end and a second end, and a modular scapular distal tip shaped to engage all or part of a glenoid surface. The scapular arm and the humeral arm are articulated relative to one another. The scapular distal tip is mechanically attached to the first end of the scapular arm.

Description

JOINT EXPOSURE DEVICE

TECHNICAL FIELD

[0001 ] The present invention relates generally to the field of surgical instrumentation for glenoid exposure. In particular, the present invention relates to a retraction device and a method of using the retraction device to expose the glenoid area of a patient.

BACKGROUND

[0002] In surgical operations, it is customary to use a retraction device to properly gain access to bone structures, joints and internal organs. Such devices are designed to hold back anatomy in the immediate area of the operative site to enable a surgeon both an optimal view of the site and a sufficient working area. Generally, the less obstructive a retraction device, the more useful it is to surgeons. Additionally, some conventional retractors require that the surgeon use one hand to operate the retractor, which leaves the surgeon with only one hand to perform surgical functions. Often, a surgical assistant must operate the retractor to maintain adequate exposure of a joint in order for the surgeon to view the operation site and to perform the bone work.

[0003] Advances have been made to gain access to the glenoid. In one method and apparatus for facilitating shoulder arthroplasty, access is gained to the glenoid through alignment of a guide with the glenoid of a scapula. The guide includes a glenoid contact surface and an anterior scapula contact surface. One form of the apparatus and method includes a guide for positioning a guide pin to facilitate implantation of a glenoid prosthesis so that the guide pin may be anchored in the glenoid and serve as an alignment guide for other devices, such as implants, used to modify the glenoid surface. (See, for example, U.S. Patent 7,294,133). While this device allows the surgeon to accurately target the glenoid cavity, it may not open up the glenoid area enough to introduce large implantation devices. [0004] Several advancements have been developed in the technology of tissue and bone retractors. One such surgical retractor design includes a pair of arms with a pivotal connection, a pair of retractor blades in which each blade is detachably connected to an arm by a rotating knee joint allowing the retractor blade to rotate, and a locking mechanism. (See, for example, US Patent 6,663,562). While this design has flexibility in angularity and motion, the retraction portion is limited in the angle at which the two retraction blades move apart from one another, requiring a customized fit for each surgical retraction, including exposure of the glenoid. Another design teaches using an alignment guide including a plate for displacing the deltoid muscle and a drill guide slidably movable along the retractor plate to expose the glenoid and assist shoulder implantations. (See, for example, US Patent 5,437,677). The retractor is designed to move muscle and soft tissues from the glenoid to provide surgical access. However, the device is not designed to open the glenohumeral joint by extending the humerus. Similarly, a European design includes a glenoid alignment guide including a retractor plate for displacing the superior and posterior aspect of the deltoid muscle and a drill guide slidably carried on the retractor plate The retractor plate has a curved finger where the tip engages the bone of the glenoid neck to clear the glenoid of muscle and tissue. (See, for example, EPO591985).

[0005] Many tissue retractors use fluid-operated expansion or bladder mechanisms.

Another design teaches a mechanically expandable retractor for use in arthroscopic surgery. The retractor includes an expanding portion for expanding against sub-surface tissues at its distal end and is controlled by a projecting portion at a proximal end (See, for example, US Patent 5,454,365). Another retractor has a mechanical expanding portion for expanding against sub-surface tissues and has an independently controllable fluid-operated expanding portion for expanding against sub-surface tissues (See, for example, US Patent 5,707,390). Current art teaches fluid operated retractors for surgical use to move tissue to provide working space and visualization space having rigid plastic plates insertable between the adjoining tissue masses, a sleeve member, and an inflatable expandable member (See, for example, US Patent 5,163,949). Such bladder devices are designed to dilate an existing stretchable space within the body, such as a blood vessel or soft tissues, rather than bone where a much larger force is required.

[0006] An important aspect of retraction devices is the ease of use. Some retraction devices must be held by the surgeon to be used; however, some devices in the current art teach surgical instruments which can be clamped onto a bone and held in place without the need of a surgical assistant (See, for example, US Patent 4,867,139). One surgical instrument for retracting muscles and other tissues includes a clamp with jaws for attachment around a bone, a blade for retracting muscles and tissues away from the bone, a pivotable mounting member to interact with the blade and a rod for support. The instrument can effectively retract muscle and tissue to expose a bone for surgery; however, it is not ideal for bone retraction because the construction of the instrument cannot easily be used to exert enough force for bone distraction. In addition, the instrument is large and obstructive in design, including a large mounting member which limits a surgeon's view of the operative site. [0007] Another patented method for performing surgery on a shoulder joint utilizes a positionable support arm attached to a retractor support apparatus. Using a retractor where the humerus retractor blade is positioned about the humerus, the humeral ball is dislocated from the glenoid cavity (See, for example, US Patent 6,368,271).

[0008] Another patent teaches a retraction apparatus for retracting anatomy in which the retractor blade is angularly-adjustable to provide exposure of the surgical area. The apparatus includes a handle rod, a body portion, a retractor blade and a mechanism which allows the retractor blade to be angularly adjusted and secured (See, for example, US Patent 5,902,233).

[0009] Additionally, some devices are created to allow assembly of an implant wholly or partially in the joint through a transosseous core approach (See, for example, US Patent 6,783,548). Such approaches aim to achieve less invasive procedures and have the ability to access the joint. The instrument used to gain access into the joint includes a large assembly through which the implant portions are guided and can be assembled (See, for example, US Patent 6,984,248).

SUMMARY

[0010] In one embodiment, the present invention is a surgical instrument for shoulder joint distraction. The surgical instrument includes a scapular arm having a first end and a second end, a humeral arm having a first end and a second end, and a scapular distal tip shaped to engage all or part of a glenoid surface. The scapular arm and the humeral arm are articulated relative to one another. The scapular distal tip is mechanically attached to the first end of the scapular arm.

[0011] In another embodiment, the present invention is a surgical shoulder joint distraction method. The method includes, in succession, gaining access to a region of a joint between a shoulder scapula glenoid cavity and a head of a humerus in a shoulder, inserting first ends of a scapular arm and a humeral arm between the shoulder scapula glenoid cavity and the head of the humerus, respectively, engaging at least part of the shoulder scapula glenoid cavity with a complementing plate, and parting the first ends of the scapular and humeral arms such that the first end of the scapular arm presses against the glenoid cavity and the first end of the humeral arm collaborates mechanically with the complementing plate to press the complementing plate against the shoulder scapula glenoid cavity. The scapular and humeral arms are articulated with respect to one another.

[0012] In yet another embodiment, the present invention is a scapular distal tip device. The scapular distal tip device includes a plate and a post. The plate has a first surface, a second surface and a perimeter between the first and second surfaces. A portion of the perimeter is substantially linear. The first surface of the plate is shaped to engage an anatomical or prosthetic glenoid surface. The post is attached to the second surface of the plate and is attachable to a glenoid retraction device.

[0013] While multiple embodiments are disclosed, still other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] FIG. 1 is a perspective view of a first part of a retraction device in accordance with the present invention.

[0015] FIG. 2 is a schematic view of the retraction device in use according to an embodiment of the present invention.

[0016] FIG. 3 is a schematic view of a first embodiment of a modular tip that can be used with a retraction device according to various embodiments of the present invention. [0017] FIG. 4 is a schematic view of a second embodiment of a modular tip that can be used with a retraction device according to various embodiments of the present invention. [0018] FIG. 5 is a schematic view of a third embodiment of a modular tip that can be used with a retraction device according to various embodiments of the present invention.

DETAILED DESCRIPTION

[0019] FIG. 1 shows a perspective view of a first part of a retraction device 10 for distracting a shoulder joint in accordance with the present invention. The retraction device 10 provides a stable, accessible and hands-free method for safely accessing and cutting, for example, the inferior capsule during a surgical procedure. The inferior capsule can be safely cut by providing wider access to the posterior aspect of the glenohumeral joint and particularly the inferior aspect of the joint. The retraction device 10 includes distraction forceps 12 having a scapular arm 14 pivotally connected to a humeral arm 16 about an axis Z-Z by an articulation means 18. Oftentimes, surgeons have difficulty exposing the glenoid joint area for accurate alignment purposes. The retraction device 10 helps the surgeon to efficiently gain access to the glenoid joint area by positioning the scapular arm 14 against a scapula S and the humeral arm 16 against a humerus H and pushing a humeral head T of the humerus H posterior- inferiorly to distract the glenoid joint.

[0020] FIG. 2 shows the retraction device 10 exposing the bones of the shoulder. The glenoid joint includes a shoulder scapula S including a coracoid process C and a humerus H. When exposed, an upper epiphysis of the humerus H is articulated at its head T against the glenoid cavity G of the shoulder scapula S. The retraction device 10 allows for a symmetrical spread as it forces the cut surface of the humerus H to be parallel to the face of the glenoid cavity G, allowing greatest exposure of the joint. Because the retraction device 10 is compact, the retraction device 10 provides the surgeon with an unobstructed view of the surgical site while performing a surgery or implantation procedure. A method of using the retraction device 10 to expose the glenoid joint area is also provided.

[0021] Each of the scapular and humeral arms 14 and 16 is in the form of an elongate rigid bar having a width and thickness substantially smaller than its length. The scapular arm 14 includes a distal end 20 and a proximal end 22 and the humeral arm 16 includes a distal end 24 and a proximal end 26.

[0022] The scapular and humeral arms 14 and 16 extend along one another and are articulated to one another at the articulation means 18 so as to be able to pivot relative to one another about the axis of articulation Z-Z. Thus, in order to move the distal ends 20 and 24 of the scapular and humeral arms 14 and 16, the surgeon manipulates the proximal ends 22 and 26, respectively, of the scapular and humeral arms 14 and 16 in such a way as to separate them or to bring them closer together. Although FIG. 1 depicts the scapular and humeral arms 14 and 16 articulated to one another substantially mid- way between the distal ends 20 and 24 and the proximal ends 22 and 26, the scapular and humeral arms 14 and 16 may be articulated substantially anywhere between the distal ends 20 and 24 and the proximal ends 22 and 26 without departing from the intended scope of the present invention. [0023] Each of the scapular and humeral arms 14 and 16 has a distal longitudinal part

28 and 30 and a proximal longitudinal part 32 and 34 which, in use, face respectively towards the user of the forceps 12 and towards the shoulder that is to be distracted. In the configuration depicted in FIG. 1, the distal parts 28 and 30 of the scapular and humeral arms 14 and 16 run substantially parallel to one another, substantially contiguously, while the proximal parts 32 and 34 are spaced from one another with a relative separation that increases along the length of the scapular and humeral arms 14 and 16 from the articulation means 18 to the proximal ends 22 and 26 of the scapular and humeral arms 14 and 16. When, in application, the scapular and humeral arms 14 and 16 are pivoted about the axis Z-Z so as to move the distal ends 20 and 24 closer together, the proximal ends 22 and 26 are moved apart, with a separation between the distal parts 28 and 30 that increases along the length of the distal parts 28 and 30 from the articulation means 18 to the distal ends 20 and 24, as depicted in FIG. 3.

[0024] The forceps 12 also include a locking mechanism 36 that locks the relative pivoted position of the scapular and humeral arms 14 and 16. In the embodiment shown in FIG. 1, the locking mechanism 36 includes a bar 38 that is articulated to the proximal end 26 of the humeral arm 16 and a set of teeth 40 that face towards the humeral arm 16. The proximal end 22 of the scapular arm 14 is shaped to engage the set of teeth 40. The locking mechanism 36 also includes a lever 42 pivotally mounted on the proximal end 22 of the scapular arm 14 so that when the lever 42 is engaged around the bar 38, as shown in FIG. 1, the lever 42 firmly holds the proximal end 22 of the scapular arm 14 in the bottom of one of the dedenda of the set of teeth 40, thus immobilizing the relative pivoted configuration of the scapular and humeral arms 14 and 16. By disengaging the lever 42 from the bar 38, the set of teeth 40 can be disengaged from the proximal end 22 of the scapular arm 14 so that the humeral arm 16 can be moved freely with respect to the scapular arm 14 about the axis Z-Z. [0025] In one embodiment, the above-described locking mechanism 36 may be reversed with respect to the scapular and humeral arms 14 and 16 such that the bar 38 is articulated to the proximal end 22 of the scapular arm 14 while the proximal end 26 of the humeral arm 16 is designed to engage the set of teeth 40. Although a particular embodiment of the locking mechanism 36 is depicted in FIG. 1, various other conceivable embodiments for the locking mechanism 36 aimed at immobilizing the articulation between the scapular and humeral arms 14 and 16 so as to maintain a fixed separation between their proximal ends 22 and 26 and therefore between their distal ends 20 and 24 may be used without departing from the intended scope of the present invention.

[0026] In one embodiment, the distal parts 28 and 30 of the scapular and humeral arms 14 and 16 have a curved longitudinal profile and includes a scapular distal tip 44, 46 configured to contact and press against the glenoid surface or a prosthesis and a humeral distal tip 58 configured to contact and press against the humeral head or a broach implanted within the humerus. The scapular distal tip 44, 46 and humeral distal tip 58 engage against respective areas of the glenoid joint in a frictional manner such that the likelihood of the retraction device 10 slipping during a surgical procedure is minimized or prevented. [0027] The scapular distal tip 44, 46 and humeral distal tip 58 are modular and are interchangeable depending on the nature of the surgical procedure being performed. As shown in FIG. 2, the retraction device 10 is used to separate the scapula S from the humeral head T by positioning the scapular distal tip 44, 46 against the glenoid cavity and the humeral distal tip 58 against the humerus. The scapular distal tip 44, 46 and humeral distal tip 58 aid to prevent slippage of the retraction device 10 during a surgical procedure by mating with the anatomical or prosthetic parts that are to be spread apart.

[0028] FIGS. 3 and 4 show schematic views of first and second embodiments of a modular scapular distal tip 44 and 46, respectively, that can be used in conjunction with the retraction device 10. FIG. 3 shows a modular scapular distal tip 44 configured to contact and press against an anatomical glenoid surface, such as the glenoid fossa. The scapular distal tip 44 includes a post 50 attached to a plate 52 having a convex face 52A and a substantially planar face 52B. The scapular distal tip 44 is attached to the distal end 28 of the scapular arm 14 by the post 50. The post 50 is attached to the substantially planar face 52B of the plate 52, which faces the forceps 12, and can be attached to the distal end 20 of the scapular arm 14 by any means known in the art. For example, the post 50 may be attached to the distal end 20 of the scapular arm 14 by fitting the post 50 into an aperture in the distal end 20 of the scapular arm 14, by mounting the post 50 to the distal end 20 of the scapular arm 14 with an adhesive or by engaging an aperture in the post 50 with the distal end 20 of the scapular arm 14. [0029] A perimeter 51 of the plate 52 is shaped to complement the anatomical glenoid surface and may include a substantially planar edge 53. The substantially planar edge 53 may be used to abut the coracoid process C. The plate 52 has the specific feature of not being flat but, by contrast, of being domed. As can be seen in FIG. 2, the convex face 52A is dimensioned so that in application, the convex face 52A covers in a substantially complementary manner part of the concave joint face of the scapula S. The convex face 52A of the plate 52 is provided with a rough surface in order to facilitate the adhesion between the convex face 52A and the scapula S. In one embodiment, the convex face 52A includes a plurality of heights to increase friction between the scapula S and the plate 52. In one embodiment, the convex face 52A is provided with a plurality of small spikes or teeth in order to facilitate adhesion between the convex face 52A and the scapula S. For example, the small spikes or teeth prevent the convex face 52A from sliding against the scapula S. Although the face 52B is discussed as being substantially planar, the face 52B may optionally be concave without departing from the intended scope of the present invention. When the scapular distal tip 44 is attached to the distal end 20 of the scapular arm 14 and engaged with the glenoid surface, the likelihood of the retraction device 10 slipping on the glenoid surface as the glenoid joint area is being spread apart is greatly reduced. [0030] FIG. 4 shows a modular scapular distal tip 46 configured to mate with a glenoid implant. Similar to the scapular distal tip 44 depicted in FIG. 3, the scapular distal tip 46 includes a post 54 attached to a plate 56 having a convex face 56A and a substantially planar face 56B. The scapular distal tip 46 is attached to the distal end 28 of the scapular arm 14 by the post 54. The post 54 is attached to the substantially planar face 56B of the plate 56, which faces the forceps 12, and can be attached to the distal end 20 of the scapular arm 14 by any means known in the art. For example, the post 54 may be attached to the distal end 20 of the scapular arm 14 by fitting the post 54 into an aperture in the distal end 20 of the scapular arm 14, by mounting the post 54 to the distal end 20 of the scapular arm 14 with an adhesive or by engaging an aperture in the post 54 with the distal end 20 of the scapular arm 14. [0031] A perimeter 55 of the plate 52 is shaped to complement the glenoid implant and may include a substantially planar edge 57. The substantially planar edge 57 may be used to abut the coracoid process C. As can be seen in FIG. 2, the convex face 56A is dimensioned so that in application, the convex face 56A covers in a substantially complementary manner part of the concave joint face of the scapula S. In contrast to the scapular distal tip 44 of FIG. 3, the convex face 56A of the scapular distal tip 46 is substantially smooth. Although the face 56B is discussed as being substantially planar, the face 56B may optionally be concave without departing from the intended scope of the present invention. When the scapular distal tip 46 is attached to the distal end 20 of the scapular arm 14 and engaged with the glenoid implant, the likelihood of the retraction device 10 slipping on the glenoid surface as the glenoid joint area is being spread apart is greatly reduced. [0032] FIG. 5 shows a modular humeral distal tip 58 configured to mate with a humeral broach 60, as shown in FIG. 2, or other prosthesis implanted within the humerus H. The humeral distal tip 58 includes a post 62 attached to a head 64. The humeral distal tip 58 is attached to the distal end 24 of the humeral arm 16 by the post 62. The post 62 is attached to a surface of the head 64 which faces the forceps 12 and can be attached to the distal end 24 of the humeral arm 16 by any means known in the art. For example, the post 62 may be attached to the distal end 24 of the humeral arm 16 by fitting the post 54 into an aperture in the distal end 24 of the humeral arm 16, by mounting the post 54 to the distal end 24 of the humeral arm 16 with an adhesive or by engaging an aperture in the post 54 with the distal end 24 of the humeral arm 16.

[0033] The head 64 of the humeral distal tip 58 is sized and shaped to mate and engage with the humeral broach 60. A perimeter 66 of the head 64 is thus shaped to complement the humeral broach 60 and may include a substantially planar edge 68. Although the humeral distal tip 58 is discussed as engaging a humeral broach, the humeral distal tip 58 may engage an anatomical humerus without departing from the intended scope of the present invention. When the humeral distal tip 58 is attached to the distal end 24 of the humeral arm 16 and engaged with the humeral broach 60, the likelihood of the retraction device 10 slipping on the humerus as the glenoid joint area is being spread apart is greatly reduced.

[0034] FIG. 2 shows the humeral distal tip 58 in use with one of the scapular distal tips 44, 46 shown in FIGS. 3 and 4, respectively. When used in combination, the scapular distal tip 44, 46 and humeral distal tip 58 of the retraction device 10 are mated with parts of the glenoid joint and prevents slippage as the glenoid joint is being spread apart. Depending on the surgical procedure being performed, alternate modular tips 44, 46, 58 are used. [0035] Various modifications and additions can be made to the exemplary embodiments discussed without departing from the scope of the present invention. For example, while the embodiments above refer to particular features of the retraction device, the scope of this invention also includes embodiments having different combinations of features and embodiments that do not include all of the retraction device features. Accordingly, the scope of the present invention is intended to embrace all such alternatives, modifications, and variations as fall within the scope of the claims, together with all equivalents thereof.

Claims

CLAIMSThe following is claimed:

1. A surgical instrument for shoulder joint distraction comprising:

a scapular arm having a first end and a second end;

a humeral arm having a first end and a second end, wherein the scapular arm and the humeral arm are articulated relative to one another; and

a scapular distal tip shaped to engage all or part of a glenoid surface, wherein the scapular distal tip is mechanically attached to the first end of the scapular arm.

2. The surgical instrument of claim 1, wherein the scapular distal tip comprises a plate.

3. The surgical instrument of claim 2, wherein the plate includes a convex surface.

4. The surgical instrument of claim 3, wherein the convex surface is rough.

5. The surgical instrument of claim 3, wherein the convex surface is substantially smooth.

6. The surgical instrument of claim 2, wherein the scapular distal tip further comprises a post for mechanically attaching the plate to the first end of the scapular arm.

7. The surgical instrument of claim 1, further comprising a humeral distal tip shaped to engage all or part of a humeral surface, wherein the humral distal tip is mechanically attached to the first end of the humeral arm.

8. A surgical shoulder joint distraction method comprising, in succession:

gaining access to a region of a joint between a shoulder scapula glenoid cavity and a head of a humerus in a shoulder; inserting a first end of a scapular arm and a first end of a humeral arm between the shoulder scapula glenoid cavity and the head of the humerus, respectively, wherein the scapular and humeral arms are articulated with respect to one another;

engaging at least part of the shoulder scapula glenoid cavity with a complementing plate; and

parting the first ends of the scapular and humeral arms such that the first end of the humeral arm presses against the head of the humerus and the first end of the scapular arm collaborates mechanically with the complementing plate to press the complementing plate against the shoulder scapula glenoid cavity.

9. The method of claim 8, further comprising dislocating the head of the humerus.

10. The method of claim 8, further comprising resecting the head of the humerus.

11. The method of claim 8, further comprising maintaining the first end of the humeral arm in spaced relation to the first end of the scapular arm.

12. The method of claim 8, wherein the complementing plate comprises a rough, convex surface.

13. The method of claim 8, wherein the complementing plate comprises a substantially smooth, convex surface.

14. The method of claim 8, further comprising engaging at least part of the head of the humerus with a complementing head.

15. The method of claim 14, wherein the complementing head engages a humeral broach in the head of the humerus.

16. A scapular distal tip device comprising:

a plate having a first surface, a second surface and a perimeter between the first and second surfaces, wherein the first surface is shaped to engage an anatomical or prosthetic glenoid surface and wherein a portion of the perimeter is substantially linear; and

a post attached to the second surface of the plate, wherein the post is attachable to a glenoid retraction device.

17. The scapular distal tip device of claim 16, wherein the plate includes a convex surface.

18. The scapular distal tip device of claim 17, wherein the convex surface is rough.

19. The scapular distal tip device of claim 17, wherein the convex surface is substantially smooth.

20. The scapular distal tip device of claim 16, wherein the plate is dome-shaped.