Metatarsal bone implant cutting guide

A method for guiding a saw blade (22) during preparation of a metatarsal (14) of a foot (10) for a procedure, such as to receive a metatarsal bone implant (20), includes positioning a housing (242) substantially adjacent to the metatarsal (14), coupling an aligner (38) to the housing (242), and aligning a saw guide (30) of the housing (242). The housing (242) includes the saw guide (30) for receiving and guiding the saw blade (22). The foot (10) includes one or more additional metatarsals (142), and the aligner (38) is used to align the saw guide (30) relative to the metatarsal (14) by aligning the aligner (38) to be substantially parallel to and positioned over a longitudinal axis (40) of one of the additional metatarsals (142).

BACKGROUND

It is well known that some people have problems with one or more joints in their feet, with particular problems being seen in the forefoot, or the front of the foot. The forefoot includes the metatarsals and the phalanges, with the joint between these bones commonly referred to as the metatarsal phalangeal joint. The majority of disease seen in toe joints affects the head of the first metatarsal, or big toe. Problems with the metatarsal phalangeal joint of a toe, most commonly with the big toe or great toe, include pain and swelling due to rheumatoid arthritis, hallux limitus (where motion is restricted due to abnormal structure or function), hallux rigidus (where motion is severely restricted or absent), pain due to an impacted joint, joint deterioration or deformation often associated with arthritis, and/or unstable or painful joints due to previous surgeries.

Several procedures have been developed to treat these conditions. For example, bone implants are often used to obtain pain relief and improve function of the metatarsal phalangeal joint. However, bone implants can only successfully enable the recipient of the bone implant to obtain pain relief and improve function of the metatarsal phalangeal joint if the bone implant is implanted accurately. In order to be able to implant the bone implant accurately, a portion of the distal end of the metatarsal must be cut and removed to allow the necessary spacing for the bone implant. An implant cutting guide can be used to line up and stabilize the area which is to be cut and removed. Accordingly, there is a need for an implant cutting guide that can accurately and repeatably align the cutting tool, e.g., a bone saw, so as to enable a proper amount of bone to be cut and removed.

SUMMARY

The present invention is directed toward a cutting guide for guiding a saw blade during preparation of a metatarsal of a foot for a procedure, such as to receive a metatarsal implant, the foot including one or more additional metatarsals. In certain embodiments, the cutting guide includes a housing and an aligner. The housing is adapted to be positioned substantially adjacent to the metatarsal. Additionally, the housing includes a saw guide for receiving and guiding the saw blade. The aligner is coupled to the housing. The aligner is used to align the saw guide relative to one of the additional metatarsals.

In some embodiments, the aligner extends substantially perpendicular to the saw guide. Additionally, in certain embodiments, the aligner can be used to be substantially aligned with a longitudinal axis of one of the additional metatarsals.

In certain embodiments, the cutting guide further includes a handle that is secured to the housing. The handle can cantilever in a generally upward direction away from the housing. In one such embodiment, the aligner is a bar that is coupled to the handle and that extends substantially perpendicular to the handle.

In one embodiment, the cutting guide can further include one or more alignment tabs that are secured to and cantilever in a generally downward direction away from the housing. In one such embodiment, the alignment tabs are adapted to be positioned within a joint gap between the metatarsal and a proximal phalanx of the foot.

In certain embodiments, the metatarsal is a first metatarsal. In one such embodiment, the aligner is used to be substantially aligned with a longitudinal axis of a second metatarsal.

In some embodiments, the housing can further include a housing top and a housing side. In such embodiments, the saw guide extends through both the housing top and the housing side. Additionally, the housing can further include a housing axis. In one such embodiment, the saw guide extends through the housing side at a guide angle of between approximately 12 degrees and 25 degrees relative to the housing axis.

DESCRIPTION

FIG. 1Ais a side view of a portion of a foot10, more particularly a left foot, of a person for supporting the person above a surface11, such as a floor or the ground, and an embodiment of a cutting guide12having features of the present invention. The foot10includes a metatarsal14having a distal end14A, and a proximal phalanx16having a proximal end16A that is positioned adjacent to the distal end14A of the metatarsal14. The distal end14A of the metatarsal14and the proximal end16A of the proximal phalanx16cooperate to form a portion of a metatarsal phalangeal joint18.

The cutting guide12is designed to be used during the preparation of the metatarsal14of the foot10to receive a metatarsal bone implant20(illustrated inFIG. 5). In particular, the cutting guide12is designed for receiving and guiding a saw blade22(illustrated as a circle) during the preparation of the metatarsal14to receive the metatarsal bone implant20.

The design of the cutting guide12can be varied depending on certain specific criteria, such as the size of the foot10. In one embodiment, the cutting guide12includes a pair of stabilizers24, one or more retraction tabs26, one or more alignment tabs28, and one or more saw guides30that receive and guide the saw blade22during the cutting of the metatarsal14. Alternatively, the cutting guide12can be designed without one or more of these features. For example, the cutting guide12can be designed without the stabilizers24.

As an overview, the cutting guide12of the present invention enables the proper, accurate and repeatable alignment of the saw blade22so as to ensure a proper amount of bone can be cut and removed from the metatarsal14to create the necessary space for the metatarsal bone implant20to be implanted in the metatarsal14. More specifically, the cutting guide12of the present invention is uniquely designed to ensure the proper and accurate alignment of the cutting guide12adjacent to the metatarsal14and the proximal phalanx16to enable the saw blade22to be positioned to remove the proper amount and the proper portion of the metatarsal14to create the necessary space for the metatarsal bone implant20.

A suitable metatarsal bone implant20that is usable in conjunction with the present invention to ensure the smooth movement of the post-operative metatarsal phalangeal joint18without otherwise interfering with the structure, integrity or functioning of the bones of the foot10can be found in U.S. patent application Ser. No. 12/421,480 entitled “Metatarsal Bone Implant” as filed by Bruce R. Lawrence and Rebecca Wahl on Apr. 9, 2009. To the extent allowable, the disclosure provided in U.S. patent application Ser. No. 12/421,480 is incorporated herein by reference.

The stabilizers24are designed to selectively and fixedly secure the cutting guide12to the metatarsal14and the proximal phalanx16to provide additional stability during use of the cutting guide12. Stated another way, the stabilizers24are designed to inhibit movement of the cutting guide12relative to the metatarsal14so as to ensure that a proper and accurate cut can be made in the metatarsal14. As illustrated, the stabilizers24can be positioned to extend through a proximal side32and a distal side34of the cutting guide12, with one stabilizer24selectively and fixedly securing the cutting guide12to the metatarsal14and the other stabilizer24selectively and fixedly securing the cutting guide12to the proximal phalanx16. In certain embodiments, the stabilizers24may be K-wires that extend through the cutting guide12to selectively and fixedly secure the cutting guide12to the foot10. Alternatively, the stabilizers24can be designed to have a different design, shape and/or orientation. Still alternatively, the cutting guide12can be designed to include more than two or less than two stabilizers24.

The one or more retraction tabs26are designed to hold the tendons and the skin of the foot10out of the way when utilizing the cutting guide12to help provide clear and unobstructed access to the metatarsal14and the proximal phalanx16of the foot10. In the embodiment illustrated inFIG. 1A, the cutting guide12is designed to include two retraction tabs26. Alternatively, the cutting guide12can be designed to have more than two or less than two retraction tabs26.

The one or more alignment tabs28are adapted to be positioned within a joint gap36within the metatarsal phalangeal joint18between the metatarsal14and the proximal phalanx16of the foot10to assist in properly aligning the cutting guide12and, more particularly, the saw guides30, relative to the metatarsal14and the proximal phalanx16of the foot10. Stated another way, the alignment tabs28are designed to extend in a generally downward direction away from a majority of the cutting guide12and into the metatarsal phalangeal joint18to ensure that the saw guides30are positioned properly along the length of the foot10so as to enable a proper cut in the metatarsal14. In the embodiment illustrated inFIG. 1A, the cutting guide12is designed to include two alignment tabs28(only one is visible inFIG. 1A). Alternatively, the cutting guide12can be designed to have more than two or less than two alignment tabs28.

The one or more saw guides30are adapted to receive and guide the saw blade22during the cutting of the metatarsal14. In this embodiment, the cutting guide12includes a proximal saw guide30A that is positioned substantially adjacent to a portion of the metatarsal14and a distal saw guide30B that is positioned substantially adjacent to a portion of the proximal phalanx16. The proximal saw guide30A is designed to receive and guide the saw blade22during the cutting of the metatarsal14. The cutting guide12as provided herein is designed to include both the proximal saw guide30A and the distal saw guide30B so that the cutting guide12can be effectively used with either a left foot, as illustrated herein inFIG. 1A, or a right foot. It should be noted that when the cutting guide12is being utilized with a right foot, the position of the proximal saw guide30A and the distal saw guide30B will be reversed. In such a situation, the distal saw guide30B will function as a proximal saw guide and be positioned adjacent to a portion of the metatarsal14and will guide the saw blade22, and the proximal saw guide30A will function as a distal saw guide and be positioned adjacent to a portion of the proximal phalanx16.

FIG. 1Bis a top view of a portion of the foot10, more particularly the left foot, and the cutting guide12illustrated inFIG. 1A. As illustrated inFIG. 1B, the foot10can include a first metatarsal141, a second metatarsal142, a third metatarsal143, a fourth metatarsal144, and a fifth metatarsal145, and the cutting guide12can be positioned substantially adjacent to the first metatarsal141. Alternatively, the cutting guide12can be positioned substantially adjacent to one of the other metatarsals142,143,144,145.

As illustrated inFIG. 1B, the cutting guide12further includes an aligner38that is adapted to be positioned in alignment with and substantially parallel to a longitudinal axis40of one of the metatarsals141,142,143,144,145. In particular, when the cutting guide12is positioned substantially adjacent to the first metatarsal141, as illustrated inFIG. 1B, the aligner38is adapted to be positioned in alignment with and substantially parallel to the longitudinal axis40of one of the other metatarsals142,143,144,145. For example, as shown, the aligner38can be positioned in alignment with and substantially parallel to the longitudinal axis40of the second metatarsal142. Alternatively, the aligner38can be designed to be positioned in alignment with and substantially parallel to the longitudinal axis40of one of the third metatarsal143, the fourth metatarsal144, or the fifth metatarsal145without altering the teachings as provided herein.

With this design, once the aligner38is approximately aligned with the longitudinal axis40by the doctor, the saw guide30is properly aligned on the first metatarsal141so that the first metatarsal141can be accurately cut in preparation for the implant20(illustrated inFIG. 5).

FIG. 2Ais a perspective view of the cutting guide12illustrated inFIG. 1A. In this embodiment, the cutting guide12includes a housing242, the one or more retraction tabs26, the one or more alignment tabs28, a handle244, the aligner38, and the saw guides30. Alternatively, the cutting guide12can be designed without one or more of these components. For example, the cutting guide12can be designed without the retraction tabs26.

The housing242is adapted to be positioned adjacent to the metatarsal14(illustrated inFIG. 1A) and the proximal phalanx16(illustrated inFIG. 1A) of the foot10(illustrated inFIG. 1A). In this embodiment, the housing242is shaped somewhat similar to a “L” rotated ninety degrees, and includes a housing top246that is adapted to be positioned adjacent to an upper surface of the metatarsal14and the proximal phalanx16, and a housing side248that is adapted to be positioned adjacent to a side surface of the metatarsal14and the proximal phalanx16. In this embodiment, the housing side248is approximately perpendicular to the housing top246.

As provided above, the retraction tabs26are designed to hold the tendons and the skin out of the way when utilizing the cutting guide12. More particularly, the retraction tabs26hold the tendons and the skin out of the way in order to provide clear and unobstructed access to the metatarsal14and the proximal phalanx16of the foot10. As illustrated, the retraction tabs26are coupled to the housing top246of the housing242and extend in a generally upward direction substantially perpendicularly away from the housing top246.

Additionally, as provided above, the alignment tabs28are adapted to be positioned within the joint gap36(illustrated inFIG. 1A) of the metatarsal phalangeal joint18(illustrated inFIG. 1A) between the metatarsal14and the proximal phalanx16of the foot10. More particularly, the alignment tabs28are adapted to assist in properly aligning the cutting guide12and, more particularly, the saw guides30relative to the metatarsal14and the proximal phalanx16of the foot10. Stated another way, the alignment tabs28are designed to extend in a generally downward direction substantially perpendicularly away from the housing top246and into the metatarsal phalangeal joint18to ensure that the saw guides30are positioned properly along the length of the foot10so as to enable a proper cut in the metatarsal14. With this design, the alignment tabs28are used to ensure that the appropriate saw guide30is positioned properly along the metatarsal14.

The handle244is coupled to the housing top246of the housing242and cantilevers in a generally upward direction away from the housing top246. The handle244is utilized to assist in positioning of the housing242adjacent to the metatarsal14and the proximal phalanx16of the foot10.

The aligner38is coupled to the housing242and is used to align the saw guides30relative to one of the metatarsals141,142,143,144,145(illustrated inFIG. 1B). In certain embodiments, the aligner38is adapted to be positioned in alignment with and substantially parallel to a longitudinal axis40(illustrated inFIG. 1B) of one of the metatarsals141,142,143,144,145. In particular, when the housing242is positioned adjacent to the first metatarsal141, the aligner38is used to align the saw guides30relative to one of the additional metatarsals142,143,144,145. For example, in one embodiment, when the housing242is positioned adjacent to the first metatarsal141, the aligner38is used to align the saw guides30relative to the second metatarsal142. In such embodiment, the aligner38can be used to be substantially aligned with and parallel to the longitudinal axis40of the second metatarsal142. Alternatively, the aligner38can be used to be substantially aligned with and parallel to the longitudinal axis40of the third metatarsal143, the fourth metatarsal144or the fifth metatarsal145.

FIG. 2Bis a front view of the cutting guide12illustrated inFIG. 2A. In particular,FIG. 2Billustrates additional features of the housing242and the aligner38of the cutting guide12.

As illustrated inFIG. 2B, the housing242can include an alignment aperture250that enables the user to view the alignment tabs28during positioning of the cutting guide12relative to the metatarsal14(illustrated inFIG. 1A) and the proximal phalanx16(illustrated inFIG. 1A). Stated another way, the alignment aperture250enables the user to view the alignment tabs28to ensure that the alignment tabs28are properly positioned within the joint gap36(illustrated inFIG. 1A) of the metatarsal phalangeal joint18(illustrated inFIG. 1A) between the metatarsal14and the proximal phalanx16.

The design of the aligner38can be varied to suit the specific requirements of the cutting guide12. In the embodiment illustrated inFIG. 2B, the aligner38is a cylindrical bar that is coupled to the handle244and that extends substantially perpendicular to the handle244. Moreover, in some embodiments, the aligner38extends away from the handle244an approximately equal amount on either side of the handle244. Alternatively, the aligner38can have a different design, a different orientation, and/or can be coupled to the housing242in a different manner.

Additionally, as illustrated inFIG. 2B, the aligner38can be positioned in a substantially parallel relationship with the housing top246. In some embodiments, the aligner38can be designed to be approximately one inch in length. Alternatively, the aligner38can be designer to be greater than or less than one inch in length.

FIG. 2Cis a side view of the cutting guide12illustrated inFIG. 2A. In particular,FIG. 2Cillustrates additional features of the retraction tabs26, the alignment tabs28and the handle244of the cutting guide12.

In certain embodiments, the retraction tabs26and the alignment tabs28can be substantially similar in design. For example, in one embodiment, each of the retraction tabs26and each of the alignment tabs28can be substantially rectangular in shape and have a width of approximately 0.18 inches, a height of approximately 0.34 inches, and a thickness of approximately 0.04 inches. Additionally, each of the retraction tabs26and each of the alignment tabs28can further include a tab connector (not illustrated) that is adapted to fit within and be retained within a retraction tab aperture352(illustrated inFIG. 3A) or an alignment tab aperture354(illustrated inFIG. 3A) included in the housing top246of the housing242. Further, in the embodiment illustrated inFIG. 2C, the retraction tabs26are positioned in a substantially parallel relationship relative to the housing side248, and the alignment tabs28are positioned in a substantially perpendicular relationship relative to the housing side248. Alternatively, the retraction tabs26and the alignment tabs28can be designed to have a different shape, to have dimensions that are greater than or less than the dimensions provided above, to have a different orientation relative to the housing side248, and/or to be coupled to the housing242in a different manner.

As illustrated inFIG. 2C, the handle244is coupled to the housing242and initially extends in a generally upward direction substantially perpendicularly away from the housing242. After the initial perpendicular positioning of the handle244relative to the housing242, another portion of the handle244extends at a handle angle256relative to the housing242. In certain embodiments, the handle angle256is approximately 30 degrees relative to the housing top246. Alternatively, the handle angle256can be greater than or less than 30 degrees relative to the housing top246.

Additionally, in certain embodiments, the handle244is designed such that when the cutting guide12is engaged with the foot10(illustrated inFIG. 1A), the end of the handle244away from the housing242is positioned at a handle height258of approximately 1.80 inches relative to the housing top246. Alternatively, the handle244can be designed to have a handle height258of greater than or less than 1.80 inches relative to the housing top246.

Additionally, as illustrated inFIG. 2C, the aligner38is spaced apart from the housing side248horizontally an alignment distance259. In one non-exclusive embodiment, the alignment distance259is approximately 1.05 inches to 1.12 inches. Alternatively, the alignment distance259can be less than approximately 1.05 inches or greater than approximately 1.12 inches.

FIG. 2Dis a top view of the cutting guide12illustrated inFIG. 2A. In particular,FIG. 2Dillustrates additional features of the handle244and the aligner38of the cutting guide12.

As illustrated in this embodiment, the handle244can be coupled to the housing top246of the housing242at a point that is substantially centrally located along the housing top246. Alternatively, the handle244can be coupled to the housing242at a different point.

Additionally, in this embodiment, the aligner38is positioned such that it is substantially parallel to the housing side248of the housing242. Further, the aligner38extends substantially perpendicular to the portion of the saw guides30that is positioned along the housing top246of the housing242. Alternatively, the cutting guide12can be designed so that the aligner38has a different orientation relative to the housing side248and the saw guides30.

FIG. 2Eis a bottom view of the cutting guide12illustrated inFIG. 2A. As illustrated in this embodiment, the handle244is substantially perpendicular to the housing side248of the housing242. Alternatively, the cutting guide12can be designed so that the handle244has a different orientation relative to the housing side248of the housing242.

FIG. 3Ais a perspective view of an embodiment of the housing242usable as part of the present invention. The design of the housing242can be varied depending on the specific requirements of the cutting guide12(illustrated inFIG. 2A) and the size of the foot10(illustrated inFIG. 1A). In this embodiment, the housing242includes the housing top246, the housing side248that cantilevers away from the housing top246, a handle aperture360that is adapted to receive a portion of the handle244(illustrated inFIG. 2A), a pair of stabilizer apertures362that are adapted to receive the pair of stabilizers24(illustrated inFIG. 1A), the alignment aperture250, one or more retraction tab apertures352that are adapted to receive a portion of the one or more retraction tabs26(illustrated inFIG. 2A), one or more alignment tab apertures354that are adapted to receive a portion of the one or more alignment tabs28(illustrated inFIG. 2A), and the pair of saw guides30.

FIG. 3Bis a top view of the housing242illustrated inFIG. 3A. In particular,FIG. 3Billustrates further details of the housing top246of the housing242. As illustrated inFIG. 3B, the housing top246of the housing242can be somewhat rectangle shaped with a housing length364of between approximately 0.84 and 0.91 inches, a greater housing width366of between approximately 0.90 and 0.99 inches, and a lesser housing width368of approximately 0.70 inches. Alternatively, the housing top246can be designed to have a different shape or to have different dimensions. For example, the housing top246can be designed to have the housing length364, the greater housing width366, and the lesser housing width368that are greater than or less than the dimensions mentioned above.

As noted above, the handle aperture360is adapted to receive a portion of the handle244and to secure the handle244(illustrated inFIG. 2A) to the housing top246of the housing242. As illustrated in this embodiment, the handle aperture360can be substantially circular in shape and can be centrally located along the housing top246of the housing242. Alternatively, the handle aperture360can have a different shape or be positioned at a different location.

Additionally, as noted above, the stabilizer apertures362are adapted to receive a portion of the stabilizers24(illustrated inFIG. 1A) and to secure the stabilizers24to the housing top246of the housing242. As illustrated, the stabilizer apertures362can be substantially circular in shape and can be positioned between approximately 0.40 and 0.47 inches from the housing side248of the housing242and can be evenly spaced on either side of the handle aperture360. Alternatively, the stabilizer apertures362can have a different shape or be positioned at a different location.

Further, as noted above, the alignment tab apertures354are adapted to receive a portion of the alignment tabs28(illustrated inFIG. 2A) and to secure the alignment tabs28to the housing top246of the housing242. As illustrated, the alignment tab apertures354can be positioned along a housing axis370and can be evenly spaced on either side of the handle aperture360. Moreover, the alignment tab apertures354can be oriented to be substantially perpendicular to the housing side248of the housing242. Alternatively, the alignment tab apertures354can have a different shape or be positioned at a different location.

Still further, as noted above, the retraction tab apertures352are adapted to receive a portion of the retraction tabs26(illustrated inFIG. 2A) and to secure the retraction tabs26to the housing top246of the housing242. As illustrated, the retraction tab apertures352can be positioned between approximately 0.62 and 0.69 inches from the housing side248of the housing242and can be evenly spaced on either side of the housing axis370and can be oriented to be substantially parallel to the housing side248of the housing242. Alternatively, the retraction tab apertures352can have a different shape or be positioned at a different location.

Additionally, the saw guides30are positioned substantially evenly spaced on either side of the housing axis370. In certain embodiments, the saw guides30can be positioned between approximately 0.345 inches and 0.415 inches on either side of the housing axis370. Alternatively, the saw guides30can be positioned at a distance of greater than 0.415 inches or less than 0.345 inches away from the housing axis370. The portion of each of the saw guides30that extends through the housing top246of the housing242is substantially perpendicular to the housing side248of the housing242.

FIG. 3Cis a front view of the housing242illustrated inFIG. 3A. In particular,FIG. 3Cillustrates further details of the housing side248of the housing242. As illustrated in this embodiment, the housing side248of the housing242can be somewhat trapezoid shaped having an outer width372of between approximately 0.90 inches and 0.99 inches that tapers down at a taper angle374of approximately 15 degrees to an inner width376of between approximately 0.68 inches and 0.79 inches, and a housing height378of approximately 0.40 inches. Alternatively, the housing side248can have a different shape or have different dimensions. For example, the housing side248can be designed to have an outer width372, an inner width376, a taper angle374, and a housing height378that are greater than or less than the dimensions mentioned above.

As illustrated inFIG. 3C, and as noted above in relation toFIG. 3B, the saw guides30are substantially evenly spaced on either side of the housing axis370. Additionally, in certain embodiments, the saw guides30extend through the housing side248of the housing242at a guide angle380relative to the housing axis370. In certain embodiments, the saw guides30can be positioned at a guide angle380of between approximately 12 degrees and 25 degrees. For example, as illustrated inFIG. 3C, the saw guides30can be positioned at a guide angle380of approximately 18 degrees relative to the housing axis370. Alternatively, the saw guides30can be positioned at a guide angle380of greater than 18 degrees or less than 18 degrees relative to the housing axis370. Further, the saw guides30can be designed to have a guide width382of approximately 0.03 inches. Alternatively, the saw guides30can be designed to have a guide width382of greater than or less than 0.03 inches.

The alignment aperture250enables the user to view the alignment tabs28(illustrated inFIG. 2A) as the cutting guide12(illustrated inFIG. 1A) is being positioned adjacent to the metatarsal14(illustrated inFIG. 1A) and the proximal phalanx (illustrated inFIG. 1A). As shown inFIG. 3C, the alignment aperture250can be positioned so that it extends an equal distance on either side of the housing axis370. Additionally, as illustrated inFIGS. 3B and 3C, the alignment aperture250extends along a portion of both the housing top246and the housing side248of the housing242. In certain embodiments, the alignment aperture250can have an aperture width384of approximately 0.31 inches. Alternatively, the alignment aperture250can have an aperture width384that is greater than or less than 0.31 inches.

FIG. 3Dis a side view of the housing242illustrated inFIG. 3A. As illustrated, the housing side248can be substantially perpendicular to the housing top246of the housing242. Additionally, the housing side248and the housing top246can be joined by a curved portion386that has a radius of approximately 0.125 inches. The curved portion386provides the cutting guide12(illustrated inFIG. 1A) with a more comfortable fit when the cutting guide12is mounted adjacent to the metatarsal14(illustrated inFIG. 1A) and the proximal phalanx (illustrated inFIG. 1A). Alternatively, the housing242can be designed without the curved portion that joins the housing side248and the housing top246, or the radius of the curved portion386can be greater than or less than 0.125 inches.

Further, in certain embodiments, the housing side248and the housing top246can have a thickness of approximately 0.06 inches, except for an end of the housing top246away from the housing side248, which can have a tapered portion388with a minimum thickness of approximately 0.02 inches and a taper angle389of approximately 16 degrees. Alternatively, the housing side248and the housing top246can be designed to have a thickness that is greater than or less than 0.06 inches, and/or the housing top246can be designed without the tapered portion388.

FIG. 4Ais a side view of an embodiment of a handle244usable as part of the present invention. The design of the handle244can be varied depending on the specific requirements of the cutting guide12(illustrated inFIG. 1A) and the size of the foot10(illustrated inFIG. 1A). In this embodiment, the handle244is coupled to the housing242(as illustrated, for example, inFIG. 2A), has a substantially circular cross-section, and includes a vertical region490, an angled region492, and a grip region494. Alternatively, the handle244can have a different design. For example, the handle244can have a cross-section that is square shaped, oval shaped, hexagon shaped, or some other shape. Further, the handle244can be deigned without the grip region494. In certain embodiments, the vertical region490, the angled region492and the grip region494are formed from a unitary structure. Alternatively, the handle244can be made up of individual parts that are joined together.

The vertical region490is coupled to the housing top246(illustrated inFIG. 2A) of the housing242(illustrated inFIG. 2A) and extends in a generally upward direction, perpendicularly away from the housing top246. In certain embodiments, the vertical region490can be approximately 0.56 inches in length. Additionally, the vertical region490can have a diameter of approximately 0.125 inches. Alternatively, the vertical region490can be greater than or less than 0.56 inches in length, and/or can have a diameter of greater than or less than 0.125 inches.

The angled region492extends at a handle angle495away from the vertical region490. In certain embodiments, the angled region492can be positioned at a handle angle495of approximately 120 degrees relative to the vertical region490. Stated another way, the angled region492can be positioned at an angle of approximately 30 degrees relative to the housing top246. Alternatively, the angled region492can be positioned at a handle angle495of greater than or less than 120 degrees relative to the vertical region490.

Additionally, the angled region492can include an aligner aperture496that is adapted to receive the aligner38(illustrated inFIG. 1A) and assists in coupling the aligner38to the handle244. As illustrated, the aligner aperture496can be positioned along the angled region492of the handle244transversely to the length of the handle244. For example, in certain embodiments, the aligner aperture496can be positioned along the angled region492approximately 0.48 inches from the vertical region490of the handle244. Alternatively, the aligner aperture496can be positioned along the angled region492greater than or less than 0.48 inches from the vertical region490of the handle244.

The grip region494extends away from the angled region492and generally maintains the same angle relative to the vertical region490as the angled region492. The grip region494is designed to be easily gripped, retained and moved by the user of the cutting guide12. For example, the grip region494can include a plurality of grooves along the outer surface of the handle244.

FIG. 4Bis a front view of the handle244illustrated inFIG. 4A. As illustrated, the handle244can further include a connector region497that is adapted to be connected to the housing top246(illustrated inFIG. 2A) of the housing242(illustrated inFIG. 2A). The connector region497is included in certain embodiments for ease of manufacture. Alternatively, in some embodiments, the handle can be designed without a specific connector region and the vertical region490can be directly connected and/or integrally formed with the housing top246.

In certain embodiments, the connector region497can have a diameter of approximately 0.154 inches and have a thickness of approximately 0.06 inches. Alternatively, the connector region497can have a diameter of greater than or less than 0.154 inches, and/or can have a thickness of greater than or less than 0.06 inches.

FIG. 4Cis a top view of the handle244illustrated inFIG. 4A. As illustrated, the angled region492of the handle244can include one or more recessed areas498. In the embodiment illustrated inFIG. 4C, the handle244includes two recessed areas498that are each approximately 0.10 inches in length and are recessed approximately 0.01 inches from the majority of the angled region492of the handle244. Alternatively, the recessed areas498can each have a length that is greater than or less than 0.10 inches, and/or can be recessed by more than or less than 0.01 inches relative to the majority of the angled region492of the handle244. The recessed areas498are included in certain embodiments for purposes of color coding different variations of the cutting guide12(illustrated inFIG. 1A). In particular, the recessed areas498are adapted to receive paint such that different variations of the cutting guide12have recessed areas498that are painted different colors. Alternatively, the handle244and/or the angled region492can be designed without any recessed areas.

FIG. 5is a side view of a portion of a foot10after a metatarsal bone implant20has been implanted into a metatarsal14that was prepared in part using a cutting guide12(illustrated inFIG. 1A) having features of the present invention. In particular, the cutting guide12was utilized to guide a saw blade22(illustrated inFIG. 1A) to cut away a portion of the metatarsal14during preparation of the metatarsal14to receive the metatarsal bone implant20. Subsequently, a hole is drilled into the metatarsal14and the metatarsal bone implant20is implanted into the hole. As illustrated inFIG. 5, the metatarsal bone implant20is implanted within the hole that has been drilled within the distal end14A of the metatarsal14, adjacent to the proximal end16A of the proximal phalanx16. Positioned in this manner, the metatarsal bone implant20effectively forms a part of a metatarsal phalangeal joint18. In one embodiment, the metatarsal bone implant20is sized and shaped to be implanted into the metatarsal of the big toe or great toe, i.e., the first metatarsal141(illustrated inFIG. 1B), of the foot10.

Additionally, with the proper cutting of the metatarsal14with use of the cutting guide12of the present invention, the metatarsal bone implant20can be implanted so as to enable the decompressing of the metatarsal phalangeal joint18, and to minimize the excessive compression of the metatarsal phalangeal joint18. The combination of the bone cut and the shape of the metatarsal bone implant20creates additional space within the metatarsal phalangeal joint18to lessen compressive forces during dorsiflexion of the metatarsal phalangeal joint18. The decompression is variable or dynamic in that the greater the dorsiflexion, the greater the decompression. Stated in another fashion, there is additional space within the metatarsal phalangeal joint18that lessens compressive forces during dorsiflexion of the metatarsal phalangeal joint18.

Further, with the proper cut in the metatarsal14, the metatarsal bone implant20can be shaped and positioned within the metatarsal14to minimize, and properly direct, the weight bearing forces that are transmitted through the metatarsal phalangeal joint18and onto the metatarsal bone implant20.