Systems and methods for the fixation or fusion of bone
Various bone fixation/fusion devices are sized and configured to be placed across fracture fragments or between bones that are to be fused.
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This application is a divisional of co-pending U.S. patent application Ser. No. 11/136,141, filed May 24, 2005, which is a continuation-in-part of co-pending U.S. patent application Ser. No. 10/914,629, filed Aug. 9, 2004.
FIELD OF THE INVENTIONThis application relates generally to the fixation of bone.
BACKGROUND OF THE INVENTIONMany types of hardware are available both for fracture fixation and for the fixation of bones that are to fused (arthrodesed).
Metal and absorbable screws are routinely used to fixate bone fractures and osteotomies. It is important to the successful outcome of the procedure that the screw is able to generate the compressive forces helpful in promoting bone healing.
SUMMARY OF THE INVENTIONThe invention provides bone fixation/fusion devices and related methods for stabilizing bone segments, which can comprise parts of the same bone (e.g., fracture fixation) or two or more individual bones (e.g., fusion). The systems and methods include a fixation/fusion device adapted for placement in association with bone segments.
One aspect of the inventions provides bone fixation/fusion systems and methods employing a body adapted for placement in association with a fracture line or between different bone segments. At least a portion of the body includes a region permitting bony in-growth and/or through-growth. The body also includes at least one fixation ridge.
Another aspect of the invention provides bone fixation/fusion systems and methods employing a body adapted for placement in association with a fracture line or between different bone segments. At least a portion of the body includes a region permitting bony in-growth and/or through-growth. The body also includes at least one guide bore accommodating passage of a guide pin.
The body can comprise, e.g., an elongated stem-like structure or a flattened wafer-like structure.
BRIEF DESCRIPTION OF THE DRAWINGS
Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention that may be embodied in other specific structure. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.
In the embodiments shown in
The bone fixation/fusion device 10 can take various shapes and have various cross-sectional geometries. The device 10 can have, e.g., a generally curvilinear (i.e., round or oval) cross-section—as
As
The region 12 can comprise, e.g., through holes, and/or various surface patterns, and/or various surface textures, and/or pores, or combinations thereof. The device 10 can be coated or wrapped or surfaced treated to provide the bony in-growth or through-growth region 12, or it can be formed from a material that itself inherently possesses a structure conducive to bony in-growth or through-growth, such as a porous mesh, hydroxyapetite, or other porous surface. The device 10 may further be covered with various other coatings such as antimicrobial, antithrombotic, and osteoinductive agents, or a combination thereof. The region 12 may be impregnated with such agents, if desired.
The configuration of the region 12 can, of course, vary. By way of examples,
In use (see
The bony in-growth or through-growth region 12 may extend along the entire outer surface of the device 10, as shown in
The size and configuration of the device 10 can be varied to accommodate the type and location of the bone to be treated as well as individual anatomy.
As
In FIGS. 9 to 12, the device 10 is cannulated, having a central lumen or throughbore 20 extending through it, to assist in the placement of the device 10 within bone.
In use, the physician can insert a conventional guide pin 22 through the bone segments 14 by conventional methods, as
Alternatively, the bone fixation/fusion device 10 itself can include screw-like threads along the body for screwing the device into place. In the arrangement, the device 10 be self-tapping. Also in this arrangement, the device 10 can be cannulated for use with a guide pin 22, or it need not be cannulated.
Multiple devices 10 may be employed to provide additional stabilization. While the use of multiple devices 10 will now be described illustrating the use of multiple devices 10 of the same size and configuration, it is contemplated that the devices 10 may also be of different size and/or configuration, e.g., one device 10 is of a cylindrical configuration and a second device 10 is of a conical configuration.
In many cases, it may be desirable to couple a series of devices 10 together, e.g., to provide stabilization over a larger surface area. A series of devices 10 may be coupled together be any suitable means, e.g., by a snap fit engagement, or a groove and tab key arrangement, or by a Morse taper fit, or combinations thereof. In one embodiment, a series of devices 10 are coupled by threaded engagement. As illustrated in
The devices 10A and 10B are desirably coupled together prior to being inserted into the pre-formed bore 26. The series of internal and external threads 30 and 32 provide an interlocking mechanism that permits a series of devices 10 to be stacked and connected to cover a larger area or multiple bone segments 14 (e.g., a bone having multiple fractures) and thereby provides additional stabilization, as seen in
In use, and as shown in
It is further contemplated that device 10′ may also be adapted for coupling with another device 10A (e.g., by a series of external and internal threads), permitting the devices 10′ and 10A to be additionally stacked and connected, as also shown in
The body 106 of the device 100 may also include a bony in-growth or through-growth region 108, as already described in association with previous embodiments.
Unlike the bone fixation/fusion device 10, the bone fixation/fusion device 100 includes at least one region associated with the body 106 that, in contrast to the body 106, comprises a material that is subject to more rapid in vivo bio-absorption or resorption by surrounding bone or tissue over time, e.g., within weeks or a few months. The resorbable material can comprise, e.g., polylactic acid (PLA), polyglycolic acid (PGA), poly(lactideglycolide) copolymers, polyanliydrides, cyclode, cirsns, polyorthoasters, n-vinyl alcohol, or other biosorbable polymers or like materials known or recognized in the prosthetic arts as having such characteristics. The bio-absorbable region is intended to facilitate implantation or placement of the body 106, but over time be absorbed to minimize the footprint of the implanted device 100 in the long run.
The bioabsorbable region or regions can possess functionality to aid in the implantation process. For example, as shown the illustrated embodiment, there are two bioabsorbable regions 102 and 104. Region 102 comprises a bioabsorbable screw region 102, which is desirably threaded or otherwise suitably configured to pierce bone and facilitate advancement of the device 100 into bone. The other region 104 comprises a bioabsorbable head region 104, which is desirably configured to mate with an installation instrument, e.g., a screwdriver, to further facilitate advancement and positioning of the bone fixation/fusion device 100 in bone. The bioabsorbable head 104 may also be sized and configured to temporarily anchor the device 100 within bone, e.g., the head 104 may be a slightly larger diameter than the body 106 of the device 100. The bioabsorbable screw portion. 102 and head portion 104 are configured to provide an immediate benefit during the initial placement or position of the device 100, but over time be resorbed when they have served their initial purpose during implantation. This leaves the more durable and less resorbable body 106 behind, to serve its longer-term function of stabilizing the fracture or fusion site.
As previously disclosed, a given bone fixation/fusion device can take various shapes and geometries. For example, as shown in
The bone fixation/fusion device 200 is desirably sized and configured to be positioned to join two or more adjacent bone segments 14 (which can comprise a fracture site, a fusion site, or both), as
As shown in
The size and configuration of the bone fixation/fusion device 200 may be modified or adjusted in diverse ways to serve the intended stabilization function in diverse bone locations, bone geometries, or bone types, which are intended to be fused or repaired. The bone fixation/fusion device 200 can come in a family of different pre-established sizes and shapes, or it can be individually sized and configured to meet the requirements of a particular individual's anatomy. For the sake of illustration, by not limitation, a given bone fixation/fusion device 200 may take the form of a disc (
As before described, a given bone fixation/fusion device can be cannulated to aid in guidance during placement or implantation. For example, as shown in
To aid in stabilizing a given bone fixation/fusion device within bone, the device may be profiled. For example, as shown in
To also aid in stabilizing a given bone fixation/fusion device within bone, the device can include one or more anti-rotational elements, which further stabilize and secure the device in the desired position within bone. The size and configuration of the anti-rotational elements may vary. For example, the anti-rotational elements may comprise an array of fins 300 projecting from a stem-like device 10 (
As also previously described, two or more bone fixation/fusion devices 200 of the types generally described above may be assembled to form a composite bone fixation/fusion device having a desired size and configuration. For example, in the arrangement shown in FIGS. 27 to 29, the bodies of two bone fixation/fusion devices 200 each have a slot 208. Slot 208 in a first device 200 mates with a like or complementary slot 208 in a second device 200 to permit the assembly of a composite bone fixation/fusion device 310, which has a crossed, anti-rotational configuration for placement across bone segments 14. The crossed relation of the composite bone fixation/fusion device 310 has an increased surface area and adds further stability to the devices 200 in bone during the fusion process.
It will be apparent to one of skill in the art that the location, size, and configuration of the slots 208 may be varied to accommodate specific needs and a specific anatomical location as well as individual anatomy. It is also apparent that other mating configurations, e.g., groove and tab fitments, or snap-fit arrangements, or Morse taper fits, or threaded assemblies, can be use to assemble two or more bone fixation/fusion devices into a composite device 310.
As shown in
In an alternative embodiment, shown in
Other forms of interlocking or nesting configuration can be used. For example, tongue-and-groove fitments, or snap-fit arrangements, or threaded fitments, or Morse taper assemblies can be use to assemble one or more fixation or gripping plates to a bone fixation/fusion device.
The fixation or gripping plate 212 is formed of durable biocompatible metal or bone substitute material, as previously described. In some cases, it may be desirable to provide a bony in-growth surface on at least a portion of the plate 212. Alternatively, the plate 212 may be formed of a bio-absorbable material, as already described.
Fixation elements can be formed in situ. For example, as shown in
In use, and with reference to
As shown in
Guide pins 204 may, if desired, be placed at opposing ends of the bored cavity 222, as seen in
An alternative embodiment is illustrated in
The foregoing is considered as illustrative only of the principles of the invention. Furthermore, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.
Claims
1. A bone fixation/fusion device comprising
- a body adapted for placement in association with a fracture line or between different bone segments, at least a portion of the body including a region permitting bony in-growth and/or through-growth, the body including at least one fixation ridge.
2. A device according to claim 1
- wherein the body includes at least two spaced-apart fixation ridges.
3. A device according to claim 2
- wherein the spaced-apart fixation ridges are separated by a distance, and
- wherein the distance remains essentially constant from one end of the fixation ridges toward an opposite end of the fixation ridges.
4. A device according to claim 1
- wherein the body includes a plurality of spaced-apart fixation ridges.
5. A device according to claim 1
- wherein the body comprises an elongated stem-like structure.
6. A device according to claim 1
- wherein the body comprises a flattened wafer-like structure.
7. A bone fixation/fusion device comprising
- a body adapted for placement in association with a fracture line or between different bone segments, at least a portion of the body including a region permitting bony in-growth and/or through-growth, the body including at least one guide bore accommodating passage of a guide pin.
8. A device according to claim 7
- wherein the body includes at least two spaced-apart guide bores.
9. A device according to claim 7
- wherein the body includes at least one fixation ridge.
10. A device according to claim 7
- wherein the body comprises an elongated stem-like structure.
11. A device according to claim 7
- wherein the body comprises a flattened wafer-like structure.
12. A method comprising
- selecting a bone site comprising a first bone segment, a second bone segment, and a non-bony region comprising an interruption between the first and second bone segments,
- providing a body including a region permitting bony in-growth and/or through-growth, the body including at least one fixation ridge, and
- inserting the body into the first bone segment, through the interruption, and into the second bone segment.
13. A method according to claim 12
- wherein the body includes at least two spaced-apart fixation ridges.
14. A method according to claim 13
- wherein the spaced-apart fixation ridges are separated by a distance, and
- wherein the distance remains essentially constant from one end of the fixation ridges toward an opposite end of the fixation ridges.
15. A method according to claim 12
- wherein the body includes a plurality of spaced-apart fixation ridges.
16. A method according to claim 12
- wherein the body comprises an elongated stem-like structure.
17. A method according to claim 12
- wherein the body comprises a flattened wafer-like structure.
18. A method comprising
- selecting a bone site comprising a first bone segment, a second bone segment, and a non-bony region comprising an interruption between the first and second bone segments,
- providing a body including a region permitting bony in-growth and/or through-growth and at least one guide bore accommodating passage of a guide pin,
- establishing with a guide pin a desired insertion path into the first bone segment, through the interruption, and into the second bone segment, and
- passing the guide bore over the guide pin to insert the body along the desired insertion path into the first bone segment, through the interruption, and into the second bone segment.
19. A method according to claim 18
- wherein the body includes at least one fixation ridge.
20. A method according to claim 18
- wherein the body comprises an elongated stem-like structure.
21. A method according to claim 18
- wherein the body comprises a flattened wafer-like structure.
22. A bone fixation assembly comprising
- a body traversing a first bone segment and a second bone segment through a non-bony region comprising an interruption between the first and second bone segments, the body including a region permitting bony in-growth and/or through-growth and including at least one fixation ridge.
23. An assembly according to claim 22
- wherein the body comprises an elongated stem-like structure.
24. An assembly according to claim 22
- wherein the body comprises a flattened wafer-like structure.
25. A bone fixation assembly comprising
- a body traversing a first bone segment and a second bone segment through a non-bony region comprising an interruption between the first and second bone segments, the body including a region permitting bony in-growth and/or through-growth and at least one guide bore accommodating passage of a guide pin along which the body is positioned.
Type: Application
Filed: Oct 31, 2007
Publication Date: Mar 13, 2008
Applicant:
Inventor: Mark Reiley (Piedmont, CA)
Application Number: 11/981,009
International Classification: A61F 2/44 (20060101);