WO2024254647A1

WO2024254647A1 - Surgical guide device

Info

Publication number: WO2024254647A1
Application number: PCT/AU2024/050625
Authority: WO
Inventors: Salvatore Samuel GRASSO; David Anthony PARKER; Brett Andrew FRITSCH; Douglas Hamilton NORTH
Original assignee: Smart Hto Pty Ltd; Personalised Surgery Pty Ltd
Current assignee: Smart Hto Pty Ltd; Personalised Surgery Pty Ltd
Priority date: 2023-06-16
Filing date: 2024-06-14
Publication date: 2024-12-19
Anticipated expiration: 2025-12-16
Also published as: AU2024304701A1

Abstract

The present invention relates to a surgical guide for assisting in osteotomy procedures comprising a guide body, a cutting slot, a plurality of openings and a guide element that is positioned at a predetermined location with respect to a feature that is located on or forms part of the patient's bone to aid in correct positioning of the surgical guide in use. The present invention also relates to a surgical system comprising the surgical guide and a preliminary guide element comprising a guide body and a duct for positioning a rod or wire on the bone. The present invention also discloses a method for manufacturing the surgical guide by performing pre- operative analysis and using the output to fabricate the surgical guide.

Description

SURGICAL GUIDE DEVICE

TECHNICAL FIELD

This disclosure relates to the field of surgical guide devices used in performing surgeries such as osteotomy.

BACKGROUND ART

It is to be understood that, if any prior art is referred to herein, such reference does not constitute an admission that the prior art forms a part of the common general knowledge in the art, in Australia or any other country.

Osteoarthiritis is a condition which results is a misalignment of bones (e.g. femur and tibia) in the knee region leading to pain. Opening wedge osteotomy is a procedure that is used to treat osteoarthritis. In this procedure, a surgeon makes a cut in the tibia or femur of the patient and inserts a wedge to open up the cut thereby adjusting the overall alignment of tibia with respect to the femur (or vice versa). Once the desired angle of correction has been achieved, the configuration of the tibia (or femur) is locked using an osteotomy plate that is fastened securely to the sections of the bone on either side of the wedge and bone graft material is inserted into the opened wedge to allow regrowth of the material. Conversely, the surgeon can make a cut and remove a wedge of bone thereby adjusting the overall alignment of tibia with respect to the femur (or vice versa). There are various types of osteotomy that may be performed. Among these, high tibial osteotomy (HTO) and distal femoral osteotomy (DFO) are procedures that are performed on the tibia and femur respectively.

The success of the osteotomy depends critically on the ability of the surgeon to follow preoperative plan. However, this makes the technique highly reliant on the surgeon’s skill and execution. Accordingly, there is a risk of the procedure not achieving the desired outcomes in a patient due to error on the part of a surgeon. There is thus a need for a device that can assist surgeons in performing opening wedge osteotomy and minimizing errors associated with the procedure.

SUMMARY

Disclosed in a first aspect is a surgical guide for assisting in osteotomy, the surgical guide comprising: a guide body, the guide body being shaped and configured to be positioned against a patient’s bone; the guide body having a proximal part and a distal part making up the guide body, a cutting slot extending through the guide body and located to guide a cut into the patient’s bone and, a plurality of openings extending through the guide body for assisting in positioning implantable elements and/or guiding drilling into the patient’s bone, at least one of the plurality of openings comprising a duct extending through the guide body in a location adjacent the cutting slot and adapted to guide the insertion of a rod or wire into the patient’s bone, a guide element configured to be positioned in a predetermined location with respect to a feature that is located on or forms part of the patient’s bone, to aid in correct in-use positioning of the surgical guide with respect to the patient’s bone. Such a device may assist a surgeon perform an opening wedge osteotomy procedure in an accurate manner. More specifically, such a device may assist a surgeon in identifying locations that need to be surgically accessed/operated upon.

In some forms the device is individually fabricated for use in a specific patient’s anatomy. This has the benefit of allowing for specific detail of the patient and specific practices of the surgeon to be incorporated into the guide prior to producing the guide. This limits the requirements for changing the guide during the operative procedure and allows for a tailored product that provides specific patient benefits. The device may be fabricated through additive manufacturing to allow for affordable individual products to be produced. In some embodiments, the duct can extend through the proximal part of the guide body in a location proximal of the cutting slot and is adapted to guide the insertion of a rod or wire into the patient’s bone.

In some embodiments, the duct can extend through the distal part of the guide body in a location distal of the cutting slot.

In some embodiments, the guide element can comprise a guide slot extending in a proximal direction from a distal edge of the distal part, the guide slot sized and positioned to be located about a rod or wire that has previously been inserted into the patient’s bone.

In some embodiments, the guide element can be positioned corresponding to a desired anatomical landmark on the patient’s bone thereby positioning the surgical guide at a desired location on the patient’s bone.

In some embodiments, the guide element can be provided as a separable part that is affixed to the surgical guide in use.

In some embodiments, the proximal part and the distal part can be separably engaged with one another.

In some embodiments, the cutting slot can be located intermediate the proximal and the distal parts.

In some embodiments, the duct can be tubular.

In some embodiments, the guide element can be formed as part of the surgical guide. This reduces the number of individual components to be handled during a surgical procedure. In some embodiments, the guide element can be formed on the proximal part of the surgical guide.

In some embodiments, the guide element comprises recesses or grooves that can correspond with features of the anatomical landmark.

In some embodiments, the recesses or grooves can comprise an indicator.

In some embodiments, the indicator can be formed from a K-wire or a cerclage wire.

In some embodiments, the indicator can be made from a radio-opaque material.

In some embodiments, the anatomical landmark can include a portion of an articulating surface between two bones in a patient.

In some embodiments, the articulating surface can include femoral condyles.

Disclosed in a second aspect is a surgical guide for assisting in osteotomy, the surgical guide comprising: a guide body, the guide body being shaped and configured to be positioned against a patient’s bone; the guide body having a proximal part and a distal part making up the guide body, a cutting slot extending through the guide body and located to guide a cut into the patient’s bone and, a plurality of openings extending through the guide body for assisting in positioning implantable elements and/or guiding drilling into the patient’s bone, at least one of the plurality of openings comprising a duct extending through the proximal part of the guide body in a location proximal of the cutting slot and adapted to guide the insertion of a rod or wire into the patient’ s bone, wherein at least one of the openings comprises a guide slot extending in a proximal direction from a distal edge of the distal part, the guide slot sized and positioned to be located about a rod or wire that has previously been inserted into the patient’s bone.

Disclosed in a third aspect is a surgical guide for assisting in osteotomy, the surgical guide comprising: a guide body, the guide body being shaped and configured to be positioned against a patient’s bone; the guide body having a proximal part and a distal part making up the guide body; a cutting slot extending through the guide body and located to guide a cut into the patient’s bone; a plurality of openings extending through the guide body for assisting in positioning implantable elements and/or guiding drilling into the patient’s bone, at least one of the plurality of openings comprising a duct extending through the proximal part of the guide body in a location proximal of the cutting slot and adapted to guide the insertion of a rod or wire into the patient’s bone; and a guide element, wherein the guide element is positioned corresponding to a desired anatomical landmark on the patient’s bone thereby positioning the surgical guide at a desired location on the patient’s bone.

Disclosed in a fourth aspect is a surgical guide system comprising: the surgical guide described hereinabove and a preliminary guide element, the preliminary guide element comprising a preliminary guide body shaped and configured to be positioned against a patient’s bone and a duct for positioning a rod or wire. The system may have the benefit of allowing for accurate positioning of essential elements for the surgery, along with allowing strong visibility and a simple step- by-step process.

Disclosed in a fifth aspect is a method of manufacturing a surgical guide described hereinabove, the surgical guide being for assisting in osteotomy on a patient’s bone, the method comprising performing at least one pre-operative step on the patient to determine the pre-operative state of the bone and utilising the resulting output of the pre-operative step to fabricate the surgical guide, the surgical guide having a shape and configuration appropriate for performing osteotomy on the patient’s bone.

In some embodiments, the pre-operative step can comprise one or more of X-ray, Computer Tomography and Magnetic Resonance Imaging (MRI).

Disclosed in some forms is a surgical guide for assisting in osteotomy, the surgical guide comprising a guide body, the guide body being shaped and configured to be positioned against a patient’s bone; the guide body having a proximal part and a distal part making up the guide body, a cutting slot extending through the guide body and located to guide a cut into the patient’s bone and, a plurality of openings extending through the guide body for assisting in positioning implantable elements and/or guiding drilling into the patient’s bone, at least one of the plurality of openings comprising a duct extending through the proximal part of the guide body in a location proximal of the cutting slot and adapted to guide the insertion of a rod or wire into the patient’s bone, at least one of the plurality of openings comprising a guide slot extending in a proximal direction from a distal edge of the distal part, the guide slot sized and positioned to be located about a rod or wire that has previously been inserted into the patient’s bone.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will now be described by way of example only, with reference to the accompanying drawings in which:

Fig. 1 shows a schematic of the surgical guide of one embodiment of the disclosure in contact with the bone;

Fig. 2 is an enlarged view of the surgical guide of Fig. 1;

Figs. 3A - 3B show a top and front views of a surgical guide of a second embodiment of the disclosure in contact with the bone;

Figs. 4A - 4C show front views of a guide element according to various embodiments of the disclosure and a surgical guide using one embodiment of the guide element.

Fig. 5 A - 5B show side and front views of the surgical guide of Fig. 4C in contact with the bone.

Figs. 6A - 6C show side and perspective views of a surgical guide with a second embodiment of the guide element partly assembled on the bone. Figs.7A - 7B show a back view of a surgical guide with one embodiment of the guide element and a side view of the surgical guide in contact with the bone

Fig. 8 shows a front view of a surgical guide according to one embodiment of the disclosure in contact with the bone

Fig. 9 shows a side view of the surgical guide according to one embodiment in use.

Fig. 10 is a schematic of a preliminary guiding element according to an embodiment of the disclosure;

Fig. 11 is a schematic of the in use steps of using the surgical guide comprising a preliminary guiding element of Fig. 10 and surgical guide of Fig. 1.

DETAILED DESCRIPTION

In the following detailed description, reference is made to accompanying drawings which form a part of the detailed description. The illustrative embodiments described in the detailed description, depicted in the drawings and defined in the claims, are not intended to be limiting. Other embodiments may be utilised and other changes may be made without departing from the spirit or scope of the subject matter presented. It will be readily understood that the aspects of the present disclosure, as generally described herein and illustrated in the drawings can be arranged, substituted, combined, separated and designed in a wide variety of different configurations, all of which are contemplated in this disclosure.

Referring to Figure 1, disclosed is a surgical guide 10 for assisting in surgery such as osteotomy. The surgical guide 10 comprises a guide body 12 configured to be positioned and secured against a patient’s bone 14. In the illustrated embodiment of Figures 1, 2, 10 and 12, the bone is a tibia. However, the surgical guide 10 can also be used with other bones such as a femur to perform procedures on the femur This is best shown in Figures 8 and 9. In use, the surgical guide is positioned against the bone during surgery. Once positioned against the bone, the guide is secured through processes such as drilling, cutting or other securing processes. The surgical guide 10 is then configured to assist a surgeon performing the procedure to accurately identify locations on the bone 14. These locations may comprise the locations for cuts, the locations for insertion of implantable elements or the location where holes need to or can be drilled.

The surgical guide 10 may be tailored to a specific patient. Patients have different distinct anatomies including different bone sizes and shapes. Accordingly, it is preferable to use distinctive cutting guides for each individual patient. In this regard, pre-operative testing may be performed on a patient to obtain measurements that will be used to design and configure the surgical guide 10 for use in osteotomy on that patient. The pre-operative testing may include imaging or measurement such as, for example, X-ray, Computer Tomography (CT) and Magnetic Resonance Imaging (MRI). Images or measurements of the knee region, bone and/or the entire lower limb extremities may be taken to determine the existing parameters of the bone and overall limb alignment such as the angle of correction required between the femur and tibia. Dynamic preoperative testing such as gait analysis may also be used to determine kinematic alignment and/or inverse dynamics to determine joint forces and moments of the patient’s anatomy and/or joint pressures in the joint of focus such as the knee.

The surgical guide may be designed in light of output from pre-operative scans, measurement and review. In some forms the medical professionals involved review the output of the scans and measurements and provide input into the shape, size and configuration of the surgical device. For example, clinicians can review measurement data to provide a desired correction alignment. This then informs the creation of the surgical guide as required and allows for optimising of features on the guide such as position of cutting slot or angulation of the drill holes based on the anatomy or the desired clinical result. The device is then manufactured on the basis of the output and the review and comments from a medical team.

By using a surgical guide that is specifically designed in light of measurements performed on the patient, a surgeon will be able to minimize the chances of errors occurring in identifying the location where incisions and cuts need to be made and holes need to be drilled to accommodate implantable elements. The surgical guide 10 may also assist in reducing the time required to perform a surgery as the surgeon is able to quickly identify locations at which the various procedures need to be performed.

As stated above, the surgical guide 10 comprises a guide body 12 which is configured to contact the bone 14 at a desired location where the surgery is to be performed. More specifically, the guide body 12 may be configured such that it extends across an incision to be made into the bone 14. In other words, the guide body 12 may be used to identify specific sites located on either side of an incision that is made into the bone 14. As discussed above, the optimum location for placement of the guide body 12 can be determined during the pre-operative planning stage to allow a surgeon to best locate incisions and specific sites for surgery.

The guide body 12 comprises a planar or substantially planar structure having a bone contacting face 20 and an opposing face 22. The planar structure is in some forms moulded to have a shape that conforms with and can be aligned with the exterior shape of the bone. The bone contacting face 20 enables the guide body 12 to contact the bone 14 and is shaped to contact the bone across a substantial portion of the bone-contacting face. In some forms the guide body 12 allows for an initial engagement with the bone that is sufficient for initial positioning of the surgical guide 10. The opposing face 22 faces away from the bone in use.

Bones (such as the tibia or femur for example) have a contoured surface. Accordingly, the guide body 12 must be capable of conforming to the surface of the bone 14 to ensure optimum positioning of the surgical guide 10. To facilitate this, the guide body 12 may be made from a material that can be shaped to engage the bone or is malleable or pliable. For example, the guide body 12 may be composed of polyamide (Nylon), PEEK or Titanium/Titanium alloy or other metal, plastic or alternative material that can be formed to make the surgical device. The surgical guide may also be amenable to being fabricated using techniques such as 3D printing that allow quick fabrication of parts in a reliable manner.

In general, the guide body 12 may be shaped and sized depending on parameters such as the length of a cut to be made, the number and size of implantable elements to be used, the spacing of these implantable elements from each other, the type, shape and size of the bone etc. As stated above, these parameters can be determined from pre-operative testing.

The guide body 12 is made up of a proximal part 16 and a distal part 18. In the illustrated embodiment, the proximal part and distal part include a plurality of openings (26, 26a) and (28, 28a) extending through the body. The openings are positioned in predetermined locations that assist a surgeon in positioning implantable elements and/or guiding drilling into the patient’s bone 14. The openings may comprise a cavity or hole, a slot or a tube or any other opening that allows for positioning of implantable elements or drilling ordinarily through the guide body.

In some forms the proximal and distal parts may be coupled or connected together to form the guide body 12 in use. Such a connection/coupling may be facilitated through the use of any attachment means such as engagement fit, adhesive, connection elements, screws or other suitable mechanisms. Alternatively, the proximal part 16 and distal part 18 may be integrally formed (i.e. from a single piece of solid material that makes up the guide body 12).

In the illustrated embodiment, the proximal part 16 comprises a head portion 36 and a leg portion 38. The head portion 36 is generally circular or semi-circular in shape and located closer to the articulating surface 32 of the bone. The head portion 36 facilitates securing the proximal part to a section of the bone on one side of the incision. The leg portion 38 extends from the head portion 36 in a longitudinal direction of the bone 14 and can facilitate connecting the proximal part to the distal part. For example, the leg portion can comprise grooves as best seen in Figure 10, or other profile or shaped elements and may be configured to receive protrusions or other shaped elements located on the distal part. In the illustrated embodiment, the head portion 36 is located on one side of the incision made on the bone with the leg portion 38 extending on the other side of the incision. It will be appreciated that the head and leg portions can be of any desirable shape and size as long as they allow the surgical guide 10 to perform the intended function.

In the illustrated embodiment, the head portion 36 is in the form of a semicircular section (as shown in Figures 1- 3 and 4c) having three openings 26a extending through the head portion from an outwardly facing face to an inwardly facing face. In the illustrated form the openings may be aligned with one another across a generally proximal end of the head. In some forms the head may include a positioning extension. In other embodiments, the head section can be configured to have other shapes and be generally square, oblong or have a shape that is similar to/conforms to the surface of the bone that it comes into contact with. For example, as best seen in Figure 7a, the head portion 36 can conform to a surface of the bone 14 it comes into contact with (see Figure 7b for assembled guide showing head portion 36).

In the illustrated embodiments, the leg portion 38 comprises an elongate hook shaped section extending away from the head portion in a distal direction. The elongate hook shaped section may be that is able to engage, hook wrap around or otherwise connect with a complementary feature located on the distal part 18. The elongate hook shaped section may be located extending from one side of a distal end of the head portion and may extend across a substantial portion or half of the head portion. The distal part 18 comprises a body portion 40 that can be coupled to the proximal part 16 to form the guide body 12. The body portion 40 extends in a longitudinal direction of the bone (i.e. similar to the leg portion 38 of the proximal part 16). The body portion 40 can also comprise tabs/protuberances (best seen in Figure 10) that can be received in the grooves present in the leg section 38 of the proximal part 16.

As discussed above the proximal and distal parts comprise a plurality of openings (26, 26a) and (28, 28a) extending through the guide body 12 for assisting in positioning implantable elements and/or guiding drilling into the patient’s bone. The openings connect the bone contacting face 20 and the opposite face 22 thus allowing the surgeon to insert wires/rods/tools that contact the bone 14.

In the illustrated embodiment, the head portion 36 of the proximal part 16 comprises 3 openings 26 (best seen in Fig. 2) and a duct 26a. The openings 26 which are arranged linearly, are configured to receive implantable elements such as screws and the like that facilitate connection between two sections of the bone formed after an incision is made. The openings can facilitate drilling of holes for receiving such screws/implantable elements. It will be apparent that the size, shape, number and location of such openings may be varied depending on the requirements. For example, a patient with a larger bone surface may require the use of 4 openings. Similarly, a patient with a smaller bone may require just 2 openings. The openings need not be arranged in a linear manner.

The duct 26a is located proximal to the cutting slot 30 (discussed further below). The duct 26a is configured to guide a rod or plate or wire that can be implanted into the bone. The location of the duct 26a is such that the inserted rod/wire is approximately parallel to the plane of the cutting slot 30. As a result, the wire/rod acts as a guide for a surgeon who is making a cut into the bone. For example, the surgeon can move the blade in a manner such that the gap between the blade and the wire/rod is maintained constant. This will ensure that the cut is made along the desired plane in the bone. The duct is angled with respect to the plane of the guide body 12. The angle may range from 10-60 degrees in any orientation (e.g. in one or a combination of coronal, sagittal or transverse planes) and may depend on the location of the tibial tubercle and/or the fibula head or fibula styloid and or the height of the metaphysis of the tibia.

The distal part 18 comprises openings in the form of a slot 28 and ducts 28a. Like the openings located on the proximal part 16, these openings connect the bone contacting face 20 with the opposite face 22 of the guide body 12. The slot 28 extends proximally into the distal part from a distal edge 42 (as best shown in Fig. 2) of the distal part 18. The slot 28 is sized to accommodate an implantable wire/rod 44 that has been previously implanted into the bone 14 and extends to a position at or beyond where the previously implanted wire/rod would be located. For example, a surgeon may insert the wire 44 before placing the proximal and distal parts on the bone 14. The dimensions and angle of the slot 28 with respect to the longitudinal axis Z of the bone 14 may be determined from pre-operative planning and testing.

The slot 28 may also facilitate correct placement of the surgical guide 10 in use. A surgeon can utilize the slot to correctly position the distal portion of the surgical guide on the bone. The slot may include markings or gradations to assist in this.

The ducts 28a may be used to guide drilling of holes into the bone 14 by the surgeon. Implantable elements such as screws/wires/rods may then be implanted into the drilled holes. The ducts 28a connect the bone contacting face 20 and the opposite face 22. In the illustrated embodiment, there are 2 ducts in the body portion 40. However, it will be apparent that the size, number, shape and location of the ducts may be varied.

In general, the ducts 26a and 28a are tubular and project outwards from the opposing face 22. However, it will be understood that the duct can take other forms as well such as including a square shaped cross section.

The proximal and distal parts may also include extensions 24a, 24b extending from the proximal and distal parts. The extensions are configured to extend laterally around the bone and increase the contact area between the guide body 12 and the bone 14 thereby improving the engagement or contact of the surgical guide 10. The extensions 24a, 24b may be integral with the guide and may be composed of the same material as the guide body 12 or other suitable materials. The extensions 24a, 24b are able to wrap around uneven/contoured surfaces of the bone providing an increased grip of the guide body 12 when placed against the bone surface.

The surgical guide 10 also comprises a cutting slot 30 extending through the guide body 12 and located to guide a cut into the patient’s bone 14. The cutting slot 30 extends through the guide body and connects the bone contacting face 20 and the opposing face 22 of the guide body 12. By inserting a cutting blade into the cutting slot 30, a surgeon is able to access the specific location of the bone 14 where an incision is to be made. In the illustrated embodiment, the cutting slot 30 is integral with the proximal part 16. However, it will be apparent to a person skilled in the art that the cutting slot 30 may be integral with the distal part as well. Alternatively, the cutting slot 30 may be provided as a separate part that may be coupled/connected to both the proximal and distal parts.

The cutting slot 30 may be located at an angle to a horizontal axis X (shown in Figs. 1 and 2) of the bone. The angle of inclination of the cutting slot 30 can be determined from measurements made during the pre-operative testing stage and in general will depend on the knee anatomy and desired correction. In the illustrated embodiment (as best seen in Figure 2), the cutting slot 30 may extend into a ridge 33 that protrudes from the opposite face 22 of the guide body 12. The elevated nature of the ridge 33 facilitates clear identification of the cutting slot 30 and prevents/minimizes interaction between the blade and other features of the surgical guide 10 when the blade is inserted into the cutting slot. In the illustrated embodiment, the cutting slot 30 extends from a lateral edge of the ridge 33 for a substantial portion of the length of the ridge 33 and bounded at an edge that is opposite to this lateral edge. Surfaces 34a, 34b of the ridge 33 that are perpendicular to the lateral edge of the ridge 33 define an upper surface of the cutting slot 30 that is visible to a surgeon. The lower surface (i.e. the surface facing the bone) of the cutting slot may be coplanar with the bone contacting surface 20 of the guide body 12.

The surgical guide 10 includes at least one guide element 13 that is configured to be positioned in a predetermined location with respect to a corresponding feature that is located on or forms part of the patient’s bone 14. Essentially, the feature acts as a point of reference on the bone that a surgeon can use to position the guide 10 such that the surgical incisions/procedures may be performed at the desired location on the bone. The guide element acts as to provide a visual indication during such a positioning of the guide 10 on the bone 14. For example, when a surface of the guide element aligns/is in desired proximity with a feature of/located on the bone (e.g. a surface at one end of the bone or previously inserted wire/rods/pins), then a surgeon can visually confirm that the guide 10 is positioned in the appropriate position to commence subsequent steps. By seeking out the feature on the bone and locating the guide element appropriately, the surgeon can minimize the time required for correctly positioning the guide 10. The guide element also prevents inadvertent errors in placement of the guide 10. For example, if the guide element does not align appropriately with the required feature on the bone thereby not providing the desired visual indication, then the surgeon can make further adjustments to the guide 10 before commencing subsequent steps in the procedure.

The guide element can take various forms as long as it performs the intended function. In its simplest form, the guide element can be a projection that extends from the surgical guide 10. In this case, a surgeon simply needs to ensure that the surface of the projection is aligned with/level with the feature on the bone.

In some forms, the guide element is in the form of a guide slot (slot 28 described above) that is located about a rod or wire that has been previously inserted into the bone 14.

In other forms, the guide element 13/113 is in the form of a wire/pin that is positioned at or near a desired anatomical landmark 15/115 (see Figures 3 and 8) on the surface of the bone. In some forms, the anatomical landmark includes a portion of an articulating surface between two bones in a patient. For example, the femoral condyles 117 (best seen in Figure 9) which are located at the end of a femur can be used as an anatomical landmark to position the surgical guide 10 using the guide element 13. Similarly, tibial plateaus which are present on the end of the tibia can also be used as the anatomical landmark to position the surgical guide 10 for procedures performed on the tibia. In the case of the femoral condyle, it can also be seen that a surface of the guiding element 113 is level with a surface of the femoral condyle. Similarly, a surface of the element 13 is level with the tibial plateau 15. Thus, in both cases, the guide elements 13/113 allow the guide 10 to be positioned at a certain distance from the ends of the bone 14 ensuring that the surgical procedures such as drilling, cutting etc. occur only in the bone and do not damage any of the other areas.

It will be apparent to a person skilled in the art that more than one guide element can be provided for a guide 10. Each guide element can be positioned at different locations on the guide that correspond to different features. For example, one or more guide elements can be provided to be positioned at locations corresponding to a cartilage, a meniscus, a ligament etc. at a knee joint. This will allow the guide 10 to be positioned with reference to multiple features of the bone 14 thus improving the accuracy of positioning.

The dimensions, shape, size and nature of the guide element to be used, its location on the guide 10 and the corresponding features to be referenced can all be determined from the pre-operative planning stage.

In some embodiments, the guide element may be provided as a separable part that is affixed to the surgical guide 10 in use. As best seen in Figures 4a - 4c, the guide element 13 (described above) is provided as a separate part that may be affixed to the proximal part 16. In the embodiment shown in Figs 4 A - 4C, the guide element 13 allows for positioning of the surgical guide with respect to anatomical landmarks. The guide element in this form comprises an attachable guide element body that is configured to be affixed to the surgical guide in use. The guide element 13 includes a locator slot for an indicator pin or wire 17 and an attachment portion that is adapted to sit atop and slot onto the head portion 36 of the proximal portion 16 of the surgical guide. The indicator pin or wire 17 may be in the form of a pin which requires a straight or fixed recess as shown in Fig 4a or a flexible wire which requires a curved slot as shown in 4B.

In the embodiment shown in Fig 5 A and 5B the guide element 13 incorporates a wire 17 in recess 13a and is affixed to the proximal portion of the surgical device. The guide element 13 is sized and shaped such that the duct and proximal section along with the cutting slot are visible and accessible in use.

In the embodiment shown in Figs. 6A through 6C, the guide element 13 includes a curved recess 13a and can be affixed to the proximal portion of the surgical guide.

Referring to Figs 7A and 7B, the guide element 13 includes a recess 13a for a indicator. The surgical guide 12 has a proximal portion 16 which is configured to engage the guide element 13 through in a facing engagement the allows the guide element to be used in conjunction with the surgical guide.

In other embodiments, the guide element may be formed as part of the surgical guide 10. For example, the guide element in the form of a guide slot 28, is formed as an integral part of the distal part 18 of the guide body 12.

In some embodiments, the guide element 13 can be formed as part of the proximal part 16 of the surgical guide 10. For example, the guide element 13 may be integrated into the proximal part 16 during manufacture. Alternatively, guide element 13 can be manufactured separately and affixed permanently or semipermanently using appropriate fastening means to the proximal part 16 of the surgical guide 10. In some embodiments, the guide element comprises recesses or grooves 13a/113a (best seen in Figures 3 - 6C, 7B and 8) that correspond with features of the anatomical landmark.

For example, as best seen in Figure 8, the recess or groove 113a is created such that it follows the contour of the femoral condyle. To position the guide 10, it may be moved up and down until the groove 113a of the guide element 113 aligns with the contour of the femoral condyle 115.

Similarly, guide 10 may also be moved such that groove 13a of element 13 aligns with the tibial plateau 15 shown in Figure 3.

These recesses or grooves can further be configured to receive an indicator 17 such as a wire/rod/pin. The indicator can function to improve the visibility by providing a contrasting appearance with respect to the rest of the surgical guide 10. This may be especially useful in a situation where blood or other debris may be blocking the view and a clear indication of the position is not obvious. The wire/rod/pin may be chosen from different types of surgical grade materials. For example, a K-wire (rigid) or a cerclage wire (flexible) can be located in the recesses/grooves. As best seen in Figures 4a and 5b, the K-wire located in the recess/groove can be clearly seen against the background of the guide element 13. The dimensions of the groove may be configured such that the wire/rod/pin can be snap fit into the recess/groove such that they are not dislodged from the recess/groove in use when the surgeon is attempting to position the guide 10.

In some embodiments, the materials chosen for the wires/rods/pins may be radioopaque enabling them to be clearly identified during various imaging (e.g. X-ray). This may allow a surgeon to verify the positioning more clearly during surgery by using such techniques.

As best seen in Figure 9, in some forms the surgical guide 10 of an embodiment of the disclosure is used to locate and drill a duct into the femur such that the duct traverses the top of the femoral condyles 117. Further ducts 118 can also be created (through the plurality of openings located on the surgical guide) which allow the insertion of screws or other components required in the surgical procedure.

Surgical system

Disclosed in another aspect is a surgical guide system 100 comprising the surgical guide 10 described hereinabove and a preliminary guide element 102. The preliminary guide element comprises a preliminary guide body 104 that is shaped and configured to be positioned against a patient’s bone 14 and a duct 106 for positioning a rod or wire 44. In the illustrated form, the preliminary guide element comprises a preliminary guide body 104 in the form of a planar or substantially planar contact portion configured to be positioned against the bone. The preliminary guide element 102 may be made from the same material as the guide body 12 described above thus enabling optimal conformance of the element to the bone 14.

The preliminary guide element 102 includes a preliminary guide duct 106 that extends through the preliminary guide body. The preliminary guide duct 106 may be located at any position on the preliminary guide body, but in the illustrated form is located at a distal position on the preliminary guide body. The preliminary guide duct facilitates the placement of a wire/rod into a bone. The duct 106 facilitates the surgeon drilling a hole into the bone 14 at a desired location and at a desired angle. Subsequently an implantable element such as a wire/rod 44 may be inserted into the bone 14. Such placement of the wire/rod 44 may have multiple uses. In the illustrated embodiment, the wire/rod 44 placed using the duct 106 acts as a cutting stop for the cutting blade making an incision in the bone. Accordingly, the surgeon will be able to stop the process of making an incision as soon as the blade contacts the wire/rod 44. This has the benefit of preventing undesirable damage to the bone structure during the process of making the incision. By varying the angle of the duct 106, the wire/rod 44 may be inserted at different angles and accordingly, the limit of the cutting depth can be varied. The angles and the cutting depth can be determined from pre-operative planning and testing. The preliminary guide element 102 may comprise extensions 108a, 108b extending from the guide body 104. As discussed above for extensions 24a, 24b, these extensions may further improve the contact between the guide element 102 and the bone 14.

In some embodiments, the guide element can be provided as part of the preliminary guide element 102. For example, the guide elements described above may be formed on the preliminary guide element 102 instead of/in addition to the guide elements formed on the proximal/distal parts.

Both the surgical guide 10 and the preliminary guide element 102 may be fabricated using well known techniques such as 3D printing. Other techniques such as injection moulding or milling may also be utilised if there is a need to mass produce specific parts.

The surgical system may comprise additional elements to assist in performing the procedure.

Surgical device in-use

Referring to Figs. 10 and 11, the use of a surgical system 100 will now be described. Prior to surgery, the surgeon performs testing to identify the preoperative state of the knee. This may be accomplished using a variety of techniques as described earlier.

Data acquired from pre-operative testing is input to a computer program that can compute the amount of correction required to the critical parameters of the bone. The output may be displayed as a series of images of the surgical device 10. For example, the computer program may generate 3D images of the surgical device 10 Such 3D images may in turn be used to fabricate the surgical guide device 10 and the preliminary guide element 102 using techniques such as 3D printing. The use of the computer program also allows for incorporation of any changes that a surgeon feels is necessary to the device configuration. Once the patient’s knee is prepped and ready for the procedure, the surgeon commences installation of the preliminary guide element 102. Following the preoperative plan, the guide element 102 is located on the specific region of the bone 14 and drilling is commenced through the tubular duct 104. Following this, a wire/rod 44 (e.g. a detensioning wire) may be inserted into the duct 104. This completes step I of the procedure as shown in Fig. 11.

In step II, the preliminary guide element 102 is removed allowing the wire/rod 44 to remain in place on the bone.

Next the surgeon places the proximal part 16 and distal part 18 together such that the slot 28 receives the wire/rod 44 which has previously been inserted into the bone. The proximal and distal part may be coupled together prior to the slot receiving the rod 44 to position on bone. Following this, both parts are secured to the bone 14 using implantable elements.

Once the proximal and distal parts are in position on the bone, a second wire/rod is inserted into the tubular duct 26a. As discussed above, this wire/rod can act as a guide for movement of the cutting blade. Following this, the surgeon drills holes into the bone 14 using the openings 26 and ducts 28a. The drills used may have calibrations on them that assist the surgeon by providing an indication on whether the desired depth has been achieved as per the pre-operative plan. Once drilling is completed, lugs are inserted into these holes through the openings 26 and 28a. Together, the lugs and the wire/rod inserted into 26a stabilize the surgical guide 10 sufficiently so that an incision can be made into the bone. Extra length of the wire/rod that has been inserted into the duct 26a may now be cut off to facilitate the use of a cutting blade to make an incision.

Following this, the surgeon can make an incision on the bone by moving the cutting blade through the cutting slot 30 to the desired depth. The cutting blade may have calibrations that provide an indication to the surgeon when the desired depth has been attained. In this regard, the surgeon may make an initial incision (e.g. posteriorly using the blade to a desired depth). Following this initial incision, the surgeon can remove the lugs inserted into the openings 26 and remove the proximal part 16 and the wire/rod inserted into duct 26a for guiding the cut while leaving the distal part 18 in place with the lugs in place in ducts 28a. The surgeon may then make a final incision (e.g. anteriorly) to complete the cut.

Following the completion of the incision, the surgeon may remove the distal part 18 together with the lugs in ducts 28a. The surgeon can leave the wire/rod 44 in place and remove the rest of the surgical guide 10. This completes the steps of using the surgical guide 10 to make the desired incisions and cuts.

After the surgical guide 10 has been removed, the surgeon proceeds to open up the cut to the desired angle as per the pre-operative plan. Different tools may be utilized to open up the cut gradually and temporary wedge spacers may then be inserted into the opened up cut to hold the cut open in the desired position.

Following this, a surgeon can now place the osteotomy plate in position and use the lugs again to hold the plate in position. Once the plate is in position, the surgeon can remove the lugs one by one, replacing them with screws that are threaded into the drilled holes in openings 26 and 28a. This will lock the osteotomy plate into position. The temporary wedge spacers and the wire/rod 44 can be removed now. and bone graft material can be inserted into the open space to complete the procedure. The surgeon can then complete the procedure by closing the region using stitches.

In addition to the above steps, where a surgeon is employing a surgical system using a guide element, an additional step of adjusting the surgical guide 10 using the guide element will be required. Ideally, this step will be performed at the beginning of the surgical procedure (i.e. before any drilling/cutting of the bone commences) However, it will be appreciated that minor adjustments may be made throughout the course of the procedure till the surgical guide 10 is removed and the plate is screwed into position. While the above illustration of the use of a surgical system is described with respect to a procedure performed on the tibia, a surgeon may use similar steps to accomplish a procedure on a femur using a guide disclosed herein. It will be understood that the number, position of openings, dimensions of cut to be made etc. may vary for a femur.

The terms proximal and distal are generally to be construed in line with anatomical terminology with reference to the origin of the limb on which the procedure is performed. In this regard, that part of the guide body 12 that is located nearer to the origin of the limb is considered as the proximal part 16 while that part of the guide body 12 which is located further away from the origin of the limb is considered the distal part 18 of the guide. However while the terms proximal and distal have been utilised to refer to the anatomical positions on the limb, in use on the femur the proximal and distal sections of the surgical guide may be reversed. In the form utilised on the femur the distal section may include the head and cutting slot while the proximal section includes the duct.

In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

Claims

1. A surgical guide for assisting in osteotomy, the surgical guide comprising: a guide body, the guide body being shaped and configured to be positioned against a patient’s bone; the guide body having a proximal part and a distal part making up the guide body, a cutting slot extending through the guide body and located to guide a cut into the patient’s bone and, a plurality of openings extending through the guide body for assisting in positioning implantable elements and/or guiding drilling into the patient’s bone, at least one of the plurality of openings comprising a duct extending through the guide body in a location adjacent the cutting slot and adapted to guide the insertion of a rod or wire into the patient’s bone, a guide element configured to be positioned in a predetermined location with respect to a feature that is located on or forms part of the patient’s bone, to aid in correct in-use positioning of the surgical guide with respect to the patient’s bone.

2. A surgical guide for assisting in osteotomy, as defined in claim 1, wherein the duct extends through the proximal part of the guide body in a location proximal of the cutting slot and adapted to guide the insertion of a rod or wire into the patient’s bone.

3. A surgical guide as defined in claim 1 , wherein the duct extends through the distal part of the guide body in a location distal of the cutting slot.

4. A surgical guide as defined in claim 1, wherein the guide element comprises a guide slot extending in a proximal direction from a distal edge of the distal part, the guide slot sized and positioned to be located about a rod or wire that has previously been inserted into the patient’s bone.

5. A surgical guide as defined in claim 1, wherein the guide element is positioned corresponding to a desired anatomical landmark on the patient’s bone thereby positioning the surgical guide at a desired location on the patient’s bone.

6. A surgical guide according to claim 5, wherein the guide element is provided as a separable part that is affixed to the surgical guide in use.

7. A surgical guide as defined in any one of claims 1 to 5, wherein the proximal part and the distal part are separably engaged with one another.

8. A surgical guide as defined in any one of claims 1 to 6, wherein the cutting slot is located intermediate the proximal and the distal parts.

9. A surgical guide as defined in any of claims 1 to 7, wherein the duct is tubular.

10. A surgical guide according to claim 5, wherein the guide element is formed as part of the surgical guide.

11. A surgical guide according to claim 10, wherein the guide element is formed on the proximal part of the surgical guide.

12. A surgical guide according to any one of claims 1 to 11, wherein the guide element comprises recesses or grooves that correspond with features of the anatomical landmark.

13. A surgical guide according to claim 12, wherein the recesses or grooves comprise an indicator.

14. A surgical guide according to claim 13, wherein the indicator is formed from a K-wire or a cerclage wire.

15. A surgical guide system according to claims 13 or 14, wherein the indicator is made from a radio-opaque material.

16. A surgical guide according to any one of claims 3 or 4 to 13 when dependent on claim 3, wherein the anatomical landmark includes a portion of an articulating surface between two bones in a patient.

17. A surgical guide according to claim 13, wherein the articulating surface includes femoral condyles.

18. A surgical guide for assisting in osteotomy, the surgical guide comprising: a guide body, the guide body being shaped and configured to be positioned against a patient’s bone; the guide body having a proximal part and a distal part making up the guide body, a cutting slot extending through the guide body and located to guide a cut into the patient’s bone and, a plurality of openings extending through the guide body for assisting in positioning implantable elements and/or guiding drilling into the patient’s bone, at least one of the plurality of openings comprising a duct extending through the proximal part of the guide body in a location proximal of the cutting slot and adapted to guide the insertion of a rod or wire into the patient’s bone, wherein at least one of the openings comprises a guide slot extending in a proximal direction from a distal edge of the distal part, the guide slot sized and positioned to be located about a rod or wire that has previously been inserted into the patient’s bone.

19. A surgical guide for assisting in osteotomy, the surgical guide comprising: a guide body, the guide body being shaped and configured to be positioned against a patient’s bone; the guide body having a proximal part and a distal part making up the guide body; a cutting slot extending through the guide body and located to guide a cut into the patient’s bone; a plurality of openings extending through the guide body for assisting in positioning implantable elements and/or guiding drilling into the patient’ s bone, at least one of the plurality of openings comprising a duct extending through the proximal part of the guide body in a location proximal of the cutting slot and adapted to guide the insertion of a rod or wire into the patient’s bone; and a guide element, wherein the guide element is positioned corresponding to a desired anatomical landmark on the patient’s bone thereby positioning the surgical guide at a desired location on the patient’s bone.

20. A surgical guide system comprising: the surgical guide of any one of claims 1 to 19; and a preliminary guide element, the preliminary guide element comprising a preliminary guide body shaped and configured to be positioned against a patient’s bone and a duct for positioning a rod or wire.

21. A method of manufacturing a surgical guide of any one of the preceding claims, the surgical guide being for assisting in osteotomy on a patient’s bone, the method comprising performing at least one pre-operative step on the patient to determine the pre-operative state of the bone and utilising the resulting output of the pre-operative step to fabricate the surgical guide, the surgical guide having a shape and configuration appropriate for performing osteotomy on the patient’s bone.

22. A method as defined in claim 21, wherein the pre-operative step comprises one or more of X-ray, Computer Tomography and Magnetic Resonance Imaging (MRI).