Bone staple with compressible deformation region

A bone staple (10) for securing a first bone region (12A) to a second bone region (12B) includes a staple body (16) having a first leg section (18), a second leg section (20), and a connector section (22). The first leg section (18) is insertable into the first bone region (12A). The second leg section (20) is insertable into the second bone region (12B). The connector section (22) connects the first leg section (18) to the second leg section (20). The connector section (22) includes a deformable region (22A) that is movable from a first configuration (14A) in which the leg sections (18) (20) are spaced apart a first distance (24) and a second configuration (14B) in which the leg sections (18) (20) are spaced apart a second distance (26) that is less than the first distance (24). In one embodiment, compression of the deformable region (22A) causes the deformable region (22A) to move from the first configuration (14A) to the second configuration (14B). As a result of this design, the bone staple (10) can easily be moved from the first configuration (14A) to the second configuration (14B). The deformable region (22A) can be substantially square ring shaped and can define a region aperture (22D) that is substantially square in the first configuration (14A). Further, the deformable region (22A) can be substantially oval ring shaped and the region aperture (22D) can be generally rectangular shaped in the second configuration (14B).

BACKGROUND

It is often necessary to fuse two bone regions to repair a fracture or to fuse a joint. On type of device used to fuse two bone regions is a compression staple that is generally “U” shaped and includes a pair of spaced apart leg sections and a connector section that connects the leg sections together. In one type of compression staple, the connector section includes a somewhat open diamond shaped region. In this type of device, the leg sections are insertable into apertures in bone regions. Subsequently, the diamond shaped region is expanded with an expansion tool. The expansion of the diamond shaped region causes the leg sections to move towards each other. This pulls the bone regions together.

Unfortunately, with this design compression staple can have a relatively large lateral profile when the staple is fully expanded.

SUMMARY

The present invention is directed toward a bone staple for securing a first bone region to a second bone region. The bone staple includes a staple body having a first leg section, a second leg section, and a connector section. The first leg section is insertable into the first bone region. The second leg section is insertable into the second bone region. The connector section connects the first leg section to the second leg section. The connector section includes a deformable region that is movable from a first configuration in which the leg sections are spaced apart a first distance and a second configuration in which the leg sections are spaced apart a second distance that is less than the first distance. In one embodiment, compression of the deformable region causes the deformable region to move from the first configuration to the second configuration. As a result of this design, the bone staple can easily be moved from the first configuration to the second configuration.

In one embodiment, the deformable region is substantially square ring shaped and defines a region aperture that is substantially square in the first configuration. Further, in one embodiment, the deformable region is substantially oval ring shaped and the region aperture is generally rectangular shaped in the second configuration.

Additionally, the connector section can include a first non-deformable region and a spaced apart second non-deformable region. Moreover, the staple body can include a pair of spaced apart first leg sections that extend into the first bone region and a pair of spaced apart second leg sections that extend into the second bone region.

The present invention is also directed to a method for securing a first bone region to a second bone region. The method can include the steps of (i) providing providing the staple body, (ii) inserting the first leg section into the first bone region; (iii) inserting the second leg section into the second bone region; and (iv) compressing the deformable region to move the deformable region from the first configuration to the second configuration.

DESCRIPTION

FIGS. 1A-1Dare alternative, simplified illustrations of a portion of a bone staple10having features of the present invention, a first bone region12A and a second bone region12B of a human. InFIGS. 1A and 1B, the bone staple10is in a first configuration14A and the bone regions12A,12B are separated; and inFIGS. 1C and 1D, the bone staple10is in a second configuration14B and the bone regions12A,12B are adjacent to each other. In this embodiment, the bone staple10is used to urge and retain the bone regions12A,12B together so that the bone regions12A,12B are fused together. The type and location of the bone regions12A,12B urged together can vary. For example, the bone staple10can be used to fuse a fracture of a human bone, to immobilize and fuse a human joint, or to fuse together adjacent bones.

In this embodiment, the bone staple10includes a generally inverted “U” shaped staple body16having a first leg section18, a second leg section20and a connector section22. The first leg section18is insertable into a first bone aperture12C in the first bone region12A. The second leg section20is insertable into a second bone aperture12D in the second bone region12D. Alternatively, the leg sections18,20can be inserted into the respective bone region12A,12B without a bone aperture.

The connector section22connects the first leg section18to the second leg section20. As provided herein, the connector section22includes a deformable region22A that is movable from the first configuration14A in which the leg sections12A,12B are spaced apart a first distance24(illustrated inFIG. 1A) and the second configuration14B in which the leg sections12A,12B are spaced apart a second distance26(illustrated inFIG. 1C) that is less than the first distance24.

In certain embodiments, compression of the deformable region22A causes the deformable region22A to move from the first configuration14A to the second configuration14B. As a result thereof, the bone staple10can be easily moved from the first configuration14A to the second configuration14B, and the bone regions12A,12B are precisely pull together.

The difference between the first distance24and the second distance26can vary according to the design requirements of the bone staple10. For example, in alternative, non-exclusive embodiments, the second distance26can be approximately 0, 0.5, 1, 2, 3, 4, 5, 6, 7, or 8 millimeters less than the first distance24. As an example, the first distance24can be between approximately 0.5 to 1.5 inches.

FIG. 2Ais a perspective view,FIG. 2Bis a side view,FIG. 2Cis an end view,FIG. 2Dis a top view of the bone staple10in the first configuration14A andFIG. 2Eis a cut-away view taken on line2E-2E inFIG. 2B. The design, size and shape of the bone staple10can vary pursuant to the teachings provided herein.

In these Figures, each of the leg sections18,20is generally straight beam shape and has a generally trapezoidal cross-sectional shape. Alternatively, one or both of the leg sections18,20can have another configuration. For example, one or both of the leg sections18,20can have a generally square, round, or oval cross-sectional shape.

Additionally, one or both of the leg sections18,20can include one or more bone engagers228that engage the respective bone region12A,12B (illustrated inFIGS. 1A-1D) to hold the respective leg section18,20in the bone region12A,12B. InFIGS. 2A-2C, each of the leg sections18,20includes three spaced apart bone engagers228that face inward, and three spaced apart bone engagers228that face outward. In this embodiment, each of the bone engagers228is generally wedge shaped and is designed to engage the respective bone region12A,12B.

The connector section22connects the leg sections18,20and allows the leg sections16,18to move between the configurations14A,14B to urge the bone regions12A,12B together. As provided above, the connector section22includes the deformable region22A that is compressed to move the leg sections16,18between the configurations14A,14B. Additionally, the connector section22can include one or more non-deformable regions. For example, in the Figures, the connector section22includes a first non-deformable region22B that secures the deformable region22A to the first leg section18, and a spaced apart second non-deformable region22C that secures the deformable region22A to the second leg section20. In this embodiment, each of the non-deformable regions22B,22C is generally straight beam shaped. Alternatively, one of both of the non-deformable regions22B,22C can have another shape or configuration.

In one embodiment, the deformable region22A is substantially square ring shaped with rounded/arched corners, and defines a region aperture22D that is substantially square with rounded/arched corners in the first configuration14A. Stated in another fashion, the deformable region22A includes a pair of slightly arched regions22AA,22AB that connect the non-deformable regions22B,22C together.

Further, as illustrated inFIG. 1D, the deformable region22A is deformed to be substantially oval ring shaped with rounded corners, and the region aperture22D is substantially oval shaped in the second configuration14B. Moreover, because of the curved shape of the arched regions22AA,22AB, compression of the deformable region22A results in a controlled buckling of the deformable region22A in which arched regions22AA,22AB are compressed and expanded outward.

Referring back toFIG. 2D, in one embodiment, the deformable region22A defines an engagement perimeter22E that is engaged by a compression tool330(illustrated inFIG. 3) so that the compression tool330can compress the deformable region22A. InFIG. 2D, the engagement perimeter22E defines four spaced apart, engagement areas22F that are engaged with the compression tool330. In this embodiment, the engagement areas22F extend transversely to the non-deformable regions22B,22C to that they can be engaged by the compression tool330. For example, the engagement areas22F can extend substantially perpendicular to the non-deformable regions22B,22C.

The size and shape of the various regions of the bone staple10can be varied pursuant to the teachings provided herein. Referring toFIGS. 2B-2D, in one non-exclusive embodiment, in the first configuration14A, (i) the connector section22has a length232of between approximately 0.567 and 1.236 inches, (ii) the connector section22has a thickness234of approximately 0.06 inches, (iii) the leg sections18, have a length236of between approximately 0.433 and 0.709 inches, (iv) the leg sections18,20have a thickness238of approximately 0.055 inches, (v) the distal tip of each of the leg sections18,20is at an angle240of approximately 45 degrees, (vi) the inner bone engagers228start a distance242of approximately 0.07 inches from the connector section22C, (vii) the outer bone engagers228start a distance244of approximately 0.21 inches from the distal tip of the leg sections18,20, (viii) each of the bone engagers228has a length246of approximately 0.06 inches, a maximum thickness248of approximately 0.016 inches, and an angled face250of approximately 15 degrees, (ix) the deformable region22A has a wall thickness252of approximately 0.055 inches, (x) the region aperture22D has a width254of approximately 0.205 inches and a length256of approximately 0.157, and (xi) the leg sections18,20have a width258of between approximately 0.120 inches. Alternatively, the bone staple10can have dimensions that are different than the example described above.

FIG. 3is a side view of the bone staple10and the compression tool330used to compress the deformable region22A of the bone staple10. The design of the compression tool330can vary. InFIG. 3, the compression tool330includes a tool grip360that engages the engagement perimeter22E of the deformable region22A, a first handle362and a second handle364that pivots relative to the first handle362to move the tool grip360and compress the deformable region22A. In the embodiment illustrated inFIG. 3, the tool grip360includes a pair of space apart first projections366(only one is shown inFIG. 3) that move with and that are secured to the first handle362, and a pair of spaced second projections368(only one is shown inFIG. 3) that move with the second handle364. The first projections366engage the engagement perimeter22E on opposite sides of the first non-deformable region22B (illustrated inFIG. 2D), and the second projections368engage the engagement perimeter22E on opposite sides of the second non-deformable region22C (illustrated inFIG. 2D). Further, the first projections366and the second projections368engage the engagement perimeter22E on opposite sides of the region aperture22D (illustrated inFIG. 2D).

With this design, movement of the second handle364relative to the first handle362causes the second projections368to move towards the first projections366and to compress the deformable region22A.

FIG. 4Ais a perspective view,FIG. 4Bis a side view,FIG. 4Cis an end view,FIG. 4Dis a top view of another embodiment of a bone staple410in the first configuration414A andFIG. 4Eis a cut-away view taken on line4E-4E inFIG. 4A. The design of this bone staple410is somewhat similar to the bone staple10described above and illustrated inFIGS. 2A-2E. However, in this embodiment, the bone staple410includes two, spaced apart first leg sections418that are inserted into the first bone region12A (illustrated inFIGS. 1A-1D), and two, spaced apart second leg sections420that are inserted into the second bone region12B (illustrated inFIGS. 1A-1D). Further, the connector section422connects the first leg sections418to the second leg sections420. Moreover, the connector section422includes a deformable region422A that is similar to the deformable region22A described above.

In certain embodiments, because of the doubling up of the leg sections418,420, the bone staple410is able to better secure the bone regions12A,12B.

It should be noted that the bone staple410could be designed with more than two first leg sections418and/or more than two second leg sections420, or that the number of first leg sections418can be different than the number of second leg sections420.

FIG. 5Ais a perspective view,FIG. 5Bis a side view, andFIG. 5Cis a top view of another embodiment of a bone staple510in the first configuration514A. The design of this bone staple510is somewhat similar to the bone staple10described above and illustrated inFIGS. 2A-2E. However, in this embodiment, the bone staple510includes two, spaced apart deformable regions522A that are separated by a non-deformable region522G and are act in series. With this design, each of the deformable regions522A can be independently deformed. This design provides a larger range of possible movement to pull the bone regions12A,12B together. For example, one or both of the deformable regions522A can be partially or fully compressed as needed to achieve the desired amount of movement to pull the bone regions12A,12B together.