Cutting Guide With Protective Insert

Abstract

A system for guiding a cutting tool in an osteotomy procedure includes a cutting block. The cutting block includes an aperture extending through a thickness of the cutting block and having a length and a width. The width of the aperture is defined between a first interior surface of the cutting block and a second interior surface of the cutting block opposing the first interior surface. The system further includes a sleeve. The sleeve includes a slot configured for receiving a sawblade and configured for insertion into the aperture of the cutting block such that the sleeve contacts either the first interior surface or the second interior surface without contacting the other interior surface.

Claims

1. A system for guiding a cutting tool in an osteotomy procedure, comprising: a cutting block, the cutting block including an aperture extending through a thickness of the cutting block and having a length and a height, the height of the aperture being defined between a first interior surface of the cutting block and a second interior surface of the cutting block opposing the first interior surface; and a sleeve, the sleeve including a slot configured to receive a sawblade and configured for insertion into the aperture of the cutting block such that the sleeve contacts either the first interior surface or the second interior surface without contacting the other interior surface, the slot having a width and a height.

2. The system of claim 1, wherein a periphery of the aperture is defined at least partially by the first and the second interior surfaces of the cutting block, and wherein either one or both of the first and the second interior surfaces include a flat portion and ribs protruding from the flat portion into the aperture.

3. The system of claim 1, wherein a profile of the aperture is such that the width of the aperture varies along the length of the aperture, and the width of the aperture at a widest point of the aperture is less than the length of the aperture.

4. The system of claim 3, wherein the profile of the aperture is substantially trapezoidal.

5. The system of claim 1, wherein a ratio of a length of the sleeve to the length of the aperture is less than 2:3.

6. The system of claim 5, wherein a ratio of a maximum length of the slot to a maximum width of the slot is between 5:1 and 50:1.

7. The system of claim 1, wherein a height of the sleeve extends along at least 50 percent of a thickness of the cutting block.

8. The system of claim 1, wherein the aperture is a first aperture, and the cutting block further includes a second aperture extending through a thickness of the cutting block.

9. The system of claim 1, further comprising: an instrument from which the sleeve extends, the instrument including an instrument body and a tongue extending from the instrument body, wherein the cutting block includes a groove extending therethrough and shaped to receive the tongue from a proximal side of the cutting block, the groove being spaced from the aperture such that the tongue may be received in the groove simultaneously with the sleeve being received in the aperture.

10. The system of claim 9, wherein a cross-sectional shape of the groove matches a cross-sectional shape of the tongue such that motion of the instrument relative to the cutting block, while the sleeve is inserted into the aperture and the tongue is inserted into the groove such that the instrument abuts the proximal side of the cutting block, is limited to a direction corresponding to withdrawal of the tongue from the groove.

11. The system of claim 1, further including an oscillating sawblade configured for receipt within the slot such that the sleeve substantially limits lateral movement of the oscillating sawblade to a region defined by the slot.

12. A method of performing an osteotomy, comprising the steps of: securing a cutting block to bone, the cutting block including a proximal surface, a distal surface opposite the proximal surface and facing the bone, and an aperture extending from the proximal surface to the distal surface; positioning an instrument adjacent to a first interior surface of the aperture and spaced from a second interior surface of the aperture such that a first portion of a slot extending through the instrument extends within the aperture; and cutting the bone with a cutting tool while the instrument is positioned against the first interior surface of the aperture and the cutting tool is extending through the first portion of the slot such that the slot limits lateral movement of the cutting tool to a region defined by the slot.

13. The method of claim 12, further comprising the step of stabilizing the instrument during the cutting by applying force to a handle of the instrument that extends away from the cutting block.

14. The method of claim 12, wherein the cutting step includes the steps of: repositioning the instrument to the second interior surface of the cutting block; and cutting the bone along the second interior surface of the cutting block while the instrument positioned against the second interior surface of the aperture.

15. The method of claim 14, wherein the positioning step includes inserting a first tongue of the instrument into a first groove of the cutting block, and the repositioning step includes inserting the first tongue or a second tongue of the instrument into a second groove of the cutting block.

16. The method of claim 15, wherein the positioning step includes inserting a tongue of the instrument into a groove of the cutting block.

17. The method of claim 15, wherein the bone forms part of a foot.

18. A method of performing an osteotomy, comprising the steps of: securing a cutting block to bone, the cutting block including a proximal surface, a distal surface opposite the proximal surface and facing the bone, and a plurality of apertures extending from the proximal surface to the distal surface; positioning a slot of an instrument within a first aperture of the plurality of apertures; cutting a first portion of the bone with a cutting tool while the slot of the instrument is positioned within the first aperture and the cutting tool is extending through the slot such that the slot limits lateral movement of the cutting tool to a region defined by the slot; repositioning the slot of the instrument within a second aperture of the plurality of apertures after the step of cutting the first portion of the bone; and cutting a second portion of the bone with a cutting tool while the slot of the instrument is positioned within the second aperture and the cutting tool is extending through the slot such that the slot limits lateral movement of the cutting tool to the region defined by the slot.

19. The method of claim 18, wherein the plurality of apertures are nonparallel such that surfaces of the bone formed by the cutting steps are nonparallel.

20. The method of claim 18, wherein the bone forms part of a foot.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] A more complete appreciation of the subject matter of the present invention and various advantages thereof may be realized by reference to the following detailed description and the accompanying drawings, in which:

[0032] FIG. 1 is a plan view of a cutting guide system according to an embodiment;

[0033] FIG. 2 is a cross-sectional view along lines 2-2 of FIG. 1;

[0034] FIGS. 3A and 3B are perspective views of the cutting guide system of FIG. 1;

[0035] FIG. 4 is a plan view of a cutting guide system according to another embodiment;

[0036] FIG. 5 is a cross-sectional view along lines 5-5 of FIG. 4; and

[0037] FIGS. 6A and 6B are perspective views of the cutting guide system of FIG. 4.

DETAILED DESCRIPTION

[0038] As used herein, the term “proximal,” when used in connection with a surgical tool or device, or components of a device, refers to the end of the device closer to the user of the device when the device is being used as intended. On the other hand, the term “distal,” when used in connection with a surgical tool or device, or components of a device, refers to the end of the device farther away from the user when the device is being used as intended. As used herein, the terms “substantially,” “generally,” “approximately,” and “about” are intended to mean that slight deviations from absolute are included within the scope of the term so modified.

[0039] Referring to FIG. 1, cutting guide system 10 includes instrument 14 and cutting block 34. Instrument 14 includes a handle 18, a head 22, and a neck 20 connecting handle 18 to head 22. Head 22 includes a slot 26 extending in a direction perpendicular to a length of handle 18. A sawblade 30, which in some arrangements may form part of cutting guide system 10, is shown received in slot 26 and extends in directions perpendicular to lengthwise directions of handle 18 and slot 26.

[0040] Cutting block 34 includes elongate apertures 38A, 38B. Apertures 38A, 38B are oriented relative to each other to match an intended angle for cuts in an osteotomy procedure. Cutting block 34 may be constructed for a specific procedure, so the angle between apertures 38A, 38B may be both patient and case specific. Cutting block 34 may be constructed with 3D printing or additive manufacturing techniques to rapidly produce cutting block 34 to specifications unique to the patient's anatomy and condition.

[0041] As shown in FIG. 2, apertures 38A and 38B extend through cutting block 34 and are defined by opposing interior surfaces 40 of cutting block 34. Handle 18, neck 20, and head 22 of instrument 14 are each roughly planar in shape except for contours where handle 18 and head 22 meet neck 20. A sleeve 42 extends from head 22 in a direction perpendicular to the planar shape of head 22 and away from handle 18 to define a height of sleeve 42. Sleeve 42 has a width perpendicular to the height of sleeve 42 and perpendicular to the direction that handle 18 extends from head 22. The width of sleeve 42 and apertures 38A, 38B may be, for example, from 10 mm to 150 mm Apertures 38A, 38B may have different widths from one another, but both apertures 38A, 38B may be at least as wide as sleeve 42. In some arrangements, a ratio of the width of sleeve 42 to the width of either aperture 38A, 38B may be less than 2:3. Slot 26 extends through head 22 and sleeve 42, and the sleeve is insertable through apertures 38A, 38B. As in the example shown, sleeve 42 may have a length that is shorter than lengths of apertures 38A, 38B. Apertures 38A, 38B may have differing lengths. However, both apertures 38A and 38B may be longer than sleeve 42 as shown. In one example, a ratio of the length of sleeve 42 to the length of either or both of apertures 38A, 38B, is less than 2:3. In another example, the ratio of the length of sleeve 42 to the length of either or both of apertures 38A, 38B is less than or equal to 1:1. With sleeve 42 disposed through either aperture 38A, 38B as illustrated, slot 26 also extends through the respective aperture 38A, 38B. A length of slot 26 is aligned with the length of sleeve 42 and is less than the length of sleeve 42. The length of slot 26 may be, for example, from 10 mm to 100 mm A width of slot 26 is perpendicular to the length of slot 26 and aligned with the width of sleeve 42 and may be, for example, 2 mm, or otherwise less than 3 mm A ratio of the length of slot 26 to the width of slot 26 may therefore be from 5:1 to 50:1. Further, a ratio of the width of slot 26 to the width of sleeve 42 may be less than 2:3.

[0042] Slot 26 acts to guide sawblade 30 relative to aperture 38A, 38B and prevents sawblade 30 from contacting interior surfaces 40. As in the example shown, apertures 38A, 38B may have a close fit to sleeve 42 that restricts possible angular orientations of the sleeve and slot 26 relative to aperture 38A, 38B while the sleeve is disposed through the aperture. Due to the close fit of apertures 38A, 38B to sleeve 42, the orientation of apertures 38A, 38B control the orientation of cuts made using cutting guide system 10 for a given sleeve in which the relative alignment of sawblade 30 and the sleeve is fixed. Thus, the necessary cutting angles and spacing required between cuts may be specified in the unique specifications according to which cutting block 34 may be manufactured, and the resulting cutting block 34 may guide instrument 14 and sawblade 30 according to the specified angles and spacing. The necessary cutting angles, or the angle of first aperture 38A relative to the second aperture 38B may be, for example, anywhere from 0° to 70°.

[0043] As shown in FIGS. 3A and 3B, cutting block 34 of cutting guide system 10 includes a patient-specific contour. Cutting block 34 has a proximal side, referring collectively to all surfaces of cutting block 34 that face more proximally than distally, that faces instrument 14 just prior to inserting the instrument into the cutting block. The proximal side of cutting block 34 includes a smooth proximal surface with planar portions on either side of a convex curve. Apertures 38A, 38B extend along the curve such that proximal openings of apertures have a non-planar profile. Cutting block 34 also has a distal side, referring collectively to all surfaces of cutting block 34 that face more distally than proximally, from which sawblade 30 extends. The distal side of cutting block 34 includes a concave distal surface that is relatively irregular compared to the proximal surface. The irregularity may be shaped to match features of the patient near bone to be cut. Such features may be specified within the unique specifications according to which cutting block 34 may be manufactured. Further, such features are designed such that a minimum thickness of cutting block 34, defined as the smallest distance between any point on the distal side of cutting block 34 and a corresponding point on the proximal side of cutting block 34, exceeds the height of sleeve 42. The minimum thickness of cutting block 34 may exceed the height of sleeve 42 by, for example, 2 mm. Further still, such features may be designed such that a maximum thickness of cutting block 34, defined as the greatest distance between any point on the distal side of cutting block 34 and a corresponding point on the proximal side of cutting block 34, is at most twice the height of sleeve 42. The height of sleeve 42 may therefore extend along at least 50% of the thickness of cutting block 34.

[0044] In use, cutting block 34 of cutting guide system 10 may be fixed to a patient proximate to a bone, e.g., a talus, navicular, cuneiform, or metatarsal bone, or bones to be cut, and then sleeve 42 may be inserted into one of apertures 38A, 38B from a proximal side of cutting block 34. Cutting block 34 may be fixed to the patient by any suitable method for keeping cutting block 34 stable while cutting bone, such as by driving fixation pins through cutting block 34 into bone. Sawblade 30 may be disposed through slot 26 from a proximal side of head 22 before, during, or after inserting sleeve 42 into aperture 38A or 38B. After sleeve 42 is inserted into aperture 38A, 38B and sawblade 30 is disposed through slot 26, sawblade 30 may be used to cut bone. In examples where sawblade 30 is part of an oscillating bone saw, cutting bone involves activating the bone saw to cut bone within boundaries set by the interaction of sleeve 42 and aperture 38A, 38B or an interior surface 40. Cutting bone may further involve either one or both of passing sawblade 30 along slot 26 and passing sleeve 42 along aperture 38, in either case moving sawblade 30 laterally relative to cutting block 34 to perform resection of the bone. In this way, the total travel of sawblade 30 is controlled by both aperture 38 and slot 26. After cutting within one aperture 38A, 38B is complete, sleeve 42 may be removed from the one aperture 38A, 38B and inserted into another aperture 38A, 38B from the proximal side of cutting block 34, and the above described process of cutting bone may be repeated along the other of apertures 38A, 38B.

[0045] Referring now to FIG. 4, cutting guide system 110 includes instrument 114 and cutting block 134 generally similar in form and function to instrument 14 and cutting block 34 of the arrangement of cutting guide system 10 illustrated in FIGS. 1-3B, with like elements numbered alike, (e.g., instruments 14 and 114, cutting blocks 34 and 134) except for distinctions set forth below.

[0046] Cutting block 134 includes a wedge shaped aperture 138 having a trapezoidal profile and two grooves 146, each groove being adjacent to and parallel to an opposing edge of aperture 138 and extending distally from a proximal surface of cutting block 134. As shown in FIG. 5, grooves 146 extend from the proximal surface of cutting block 134 to a distal surface of the cutting block. A tongue 150 extends distally from head 122 perpendicular to sleeve 126 and is insertable into groove 146. Grooves 146 are sized to have a close fit to tongue 150 such that instrument 110 is prevented from rotating or translating relative to cutting block 134 except for moving proximally or distally within the plane of sawblade 130 when tongue 150 is disposed in groove 146. Grooves 146 are spaced from aperture 138 such that sleeve 126 will be held against the adjacent one of interior surfaces 140 defining aperture 138. Grooves 146 and aperture 138 thereby cooperate to dictate possible cutting paths achievable by use of instrument 110 with cutting block 134. Locations, sizes, and orientations of grooves 146 and aperture 138 may be specified within parameters unique to a patient's anatomy and condition according to which cutting block 134 may be constructed. For example, opposing interior surfaces 140 of aperture 138 may be angled with respect to one another by, for example, anywhere from 0° to 70°, and the angle of opposing interior surfaces 140 of cutting block 134 with respect to one another may correspond to an angle of cut paths dictated by cutting block 134 with respect to one another. According to other arrangements, one or both of grooves 146 may have a greater width than a width of tongue 150 such that instrument 110 may slide along the one or both of the grooves laterally relative to cutting block 134. Because of the trapezoidal profile of aperture 138, and the alignment of grooves 146 with the non-parallel internal faces 140, such lateral sliding permits adjustment of spacing of cuts dictated by cutting block 134 without permitting any variance in the relative angle defined by the cuts, as sliding sleeve 142 along one of the non-parallel internal surfaces 140 will change the distance of sleeve 142 from the opposing internal surface 140 while maintaining a constant angle between sleeve 142 and the opposing internal surface 140.

[0047] As shown in FIGS. 6A and 6B, instrument 114 may be applied to the proximal surface of cutting block 134 such that tongue 150 extends distally into groove 146, sleeve 142 extends distally into aperture 138, and saw blade 130 extends distally through and out of aperture 138. Grooves 146 extend along an arcuate portion of cutting block 134 such that their respective openings on the proximal and distal surfaces of cutting block 134 have non-planar profiles.

[0048] Cutting guide system 110 may be used by securing or fixing patient-specific cutting block 134 to the patient proximal to a bone or bones to be cut by any known method, such as by pins or screws. Instrument 114 may be applied to cutting block 134 such that tongue 150 is disposed within one of grooves 146 and sleeve 142 is disposed within aperture 138 along one of interior surfaces 140. With instrument 114 so positioned, sawblade 130 may be used through slot 126 to cut bone along the one interior surface 140. After bone is cut along the one interior surface 140, instrument 114 may be removed such that tongue 150 is withdrawn from groove 146 and sleeve 142 is withdrawn from aperture 138. Instrument 114 may then be repositioned for a second cut, which may include reapplying instrument 114 to cutting block 134 such that tongue 150 is disposed in another of grooves 146 and sleeve 142 is disposed within aperture 138 along another of interior surfaces 140. Sawblade 130 may then be used through slot 126 to cut bone along the other interior surface 140.

[0049] Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims.