Patent Description:
Canine Hip Dysplasia (CHD) is a common developmental abnormality of the hip joints in dogs. The hip dysplasia is characterized by, among other things, abnormalities in inclination and anteversion of the femoral neck, leading to incongruity of the hip joint components, uneven loading of the joint surface and stretching of the joint capsule.

Among dogs, the disease mainly affects medium-sized dogs weighing from <NUM> to <NUM>, large dogs weighing from <NUM> to <NUM> and very large dogs weighing more than <NUM>, in which the epidemiology of prevalence can be as high as <NUM>%, as in the case of Great Danes. One of the ways to manage dysplasia are corrective pelvic osteotomies which are recognized as effective techniques to prevent the subsequent development of hip joint osteoarthritis.

The first corrective pelvic osteotomy technique, specifically a Triple Pelvic Osteotomy (TPO) in dogs, was introduced by B. Slocum in <NUM>. The TPO procedure was a three-stage osteotomy of the pelvic bones consisting in excision of a fragment of the pubic bone, incision of an ischium and incision of a diaphysis of the hip bone with closure of the osteotomy using a correction plate. The aim of the procedure was to achieve ventrolateral rotation of the bony element along with an acetabulum of the hip joint. During the surgery, an acetabular segment was rotated to achieve the desired ventral inclination and provide better coverage of a femoral head for a poorly formed acetabular.

As a result of the procedure there was an increase in a bearing surface area within an articular cartilage of the acetabulum which, according to the intention of the authors of the technique, should limit the development of degeneration in the hip joint.

The degree of correction and the choice of osteotomy technique are finally selected during the X-ray or radiographic examination. The introduction of new solutions, such as locked TPO/DPO plates, multiplanar, and the development of new surgical techniques, that are DPO and <NUM>. 5PO, have led to a reduction in the invasiveness of the procedure. Despite these changes, no significant tooling, such as a guide for the cutting blade, has been proposed as far. The techniques of TPO, DPO and <NUM>. 5PO which differ from each other, are connected by a stage of the procedure consisting in the osteotomy of the hip bone diaphysis. The shortage of a guide forces the operator or surgeon to perform the so-called "freehand cut" of the hip bone diaphysis. As a result of such procedure, intraoperatively, the following may occur: damage to the cortex of the hip bone diaphysis, non-orthogonal osteotomy planes, soft tissue damage. Non-orthogonality of the osteotomy surface in the postoperative period becomes a cause of implant loosening, excessive coverage of the femoral head by the acetabular cap, and/or delayed healing of the hip bone and ischial bone osteotomies. The postoperative complication rate ranges from <NUM>% to <NUM>% of cases.

The TPO technique described by B. Slocum provides essential rules for its implementation. The first step of the procedure is determination of an auxiliary line which is a long axis of the pelvis which is led from the ischial tuberosity through the highest point of the acetabular labrum cephalad and which divides the pelvis in a longitudinal axis. The second step of the procedure is determination of an osteotomy line which is led from the point determined by the dorsocaudal iliac spine of the ilium at an angle of <NUM>° to the previously determined auxiliary line which is the long axis of the pelvis.

Determining the osteotomy line at the angle of <NUM>° in relation to the long axis of the pelvis guarantees that the bone screws stabilizing the TPO/DPO plate in the cranial fraction of the osteotomy, passing through a wing of the ilium will be inserted at the level of an auricular surface into a diaphysis of sacrum. This is a key stage of osteosynthesis, guaranteeing its stability and strength. So far, the technique of determining the osteotomy line has not been optimized by any procedure or tool and the iliac shaft or diaphysis osteotomy has been performed using the so-called "freehand cut".

Publication <CIT> of the patent application description titled "Bone cutting guide system for osteochondral transplantation" presents a bone cutting guide for preparing both donor and recipient bone, including one or more articular referencing platforms contoured to a bony surface to be prepared, fixation structure to secure the articular referencing platforms on an articular surface, cutting slots spaced apart from the articular referencing platforms at predetermined distances configured to allow the passage of a saw blade in such a way to remove a bone segment either from an allograft donor or from a graft recipient.

In turn, publication <CIT> of the patent application description titled "Patient-specific template for total ankle replacement" discloses an alignment guide for total ankle replacement surgery and a method of creating and using the alignment guide. The alignment guide has a surface that interfaces with a corresponding surface of a superior aspect a talus of a patient, and as second surface portion that interfaces with a corresponding distal surface of a section of a tibia of the patient. When the alignment guide is in position, it maintains the ankle of the patient in a preselected position.

Publication <CIT> of the patent application description titled "Patient-specific ankle guide systems and methods" teaches devices for assisting in performing an ankle arthroplasty on a non-resected bone surface of a tibia and/or a talus. The devices have patient-specific mating surfaces configured to engage the non-resected bone surface in a single relative position relative to the non-resected bone surface. The patient-specific nature of the mating surface portion may be generated in the devices prior to the devices being brought into contact with the bone. The devices may include various cutting guides and holes for receiving fasteners to fasten the devices to the bone and various features to enhance the stability and/or surface area contact between the devices and the bones.

Furthermore, publication <CIT> of the international patent application description titled "Limb and joint sparing in mammals using patient-specific surgical guides and implant with textured muscle attachment zones" shows patient-specific surgical guides used for replacing an excised of proximal humerus. The cutting guide's shape is primarily influenced by the shape of the bone to excise and the cutting guide length depends on the resection margin established by the surgeon to prevent tumor recurrence.

The above described guides are suitable for using the guides at cutting of bones of dedicated pets or humans The aim of the invention is to create a tool that would enable precise determination of an osteotomy line and perform a cutting of a hip bone in an optimized manner, ensuring an orthogonality of osteotomy planes.

The aim is achieved according to the invention by means of a guide of a cutting tool blade or a saw, having the features of claim <NUM>. Advantageous embodiments of the invention are defined in the respective dependent claims.

According to the invention, a guide of a saw blade comprises a guiding element whose body has a shape of a solid fitting into a cuboid and which has a longitudinal through hole or a slit for guiding the cutting tool blade used for the procedure having a width not greater than <NUM>,<NUM> and a length b smaller than a longitudinal dimension, i.e. the longest dimension of the body of the guiding element that is situated perpendicular to a bottom wall or surface whereby the guiding element has a set of at least three through mounting holes with a diameter not greater than <NUM>,<NUM> whose outlets are located within the bottom wall or surface of the guiding element, two of which are situated on one side of the longitudinal through hole or slit and at least one is situated on an opposite side of a longitudinal axis of symmetry of the through hole or slit in relation to a side on which the two through mounting holes are located, whereas orthogonal projections of the outlets of the most distanced through mounting holes from each other and situated on one side of the longitudinal through hole or slit on the longitudinal axis of symmetry of the through hole or slit are located between opposite walls of the through hole or slit wherein the guide of the saw blade has a slider and in the body of the guiding element there is a transverse through hole perpendicular to the longitudinal axis of symmetry of the longitudinal through hole with a cross-sectional shape and dimensions corresponding to a shape and dimensions of a cross-sectional profile of the slider and the slider is movably positioned within the transverse through hole and has a stabilizing hole nearby its free end and the guide of the saw blade has a locking screw and in the body of the guiding element there is a threaded hole that runs from an upper wall or surface of the guiding element to at least the transverse through hole and in which a locking screw is screwed in.

In one preferred embodiment the guide of saw blade is suitable for a straight blade of the saw for double and triple pelvic osteotomies in dogs.

Preferably, the bottom wall or surface of the guiding element is flat and the through hole is perpendicular to the flat bottom wall or surface of the guiding element.

According to one preferred embodiment, a particularly advantageous use of the guide according to the invention can be seen in that the body of the guiding element is a board having a shape of rectangular parallelepiped or cuboid with a base that is a rectangle with rounded corners.

There can be recesses or indentations in a side walls of the body of the guiding element.

According to another structural variant of the invention, it is advantageous that the guide has a cylindrical insert with a longitudinal through hole of a width not exceeding <NUM>,<NUM> whose outer contour of a cross-section corresponds in shape and dimensions to a longitudinal hole made in the body of the guiding element enlarged in all transverse directions by a thickness of the walls of the cylindrical insert compared to the longitudinal through hole.

The guiding element can be formed as a board with a thickness ranging from <NUM>,<NUM> to <NUM>,<NUM>, a width ranging from <NUM>,<NUM> to <NUM>,<NUM> and a length ranging from <NUM>,<NUM> to <NUM>,<NUM>.

According to a further development of the invention, this is particularly advantageous that the set of mounting holes has an even number of mounting holes forming two sub-sets of mounting holes with an equal number of mounting holes whereas the sub-sets of mounting holes are located on opposite sides of the longitudinal through hole or slit and distances of holes from edges of the longitudinal through hole or slit are the same.

The main aspect of the design of the straight oscillating saw blade guide are the guiding element and the slider of the guide. The combination of the slider and the guiding element allows for the determination of the osteotomy line at an angle of <NUM>° relative to the long axis of the pelvis. The effect of using the guide is the ability to cut the hip bone of an animal, especially a dog, in a precisely defined place.

The subject of the invention has been shown in the attached drawing, where:.

A guide <NUM> of a saw blade <NUM> or other cutting tool in the embodiment shown in <FIG> comprises a guiding element <NUM> whose body <NUM> has a shape of a solid fitting into a cuboid. In one embodiment the guiding element <NUM> has a longitudinal through hole or a slit <NUM> having a width c adapted to the thickness of the saw blade or other cutting tool, in particular not greater than <NUM>,<NUM> and a length b smaller than a longitudinal dimension of the body <NUM> of the guiding element <NUM>. In particular, the longitudinal through hole or slit <NUM> is located in the middle of the solid fitting into a cuboid. Preferably, the length b of the hole is selected on the basis of X-ray images of the bones, such that said length is greater than the width of the bone at the intended osteotomy site. The length of the longitudinal through hole or slit can be adjusted according to the anticipated surgical conditions. The longitudinal through hole or slit <NUM> in particular is perpendicular to the bottom wall of the guiding element <NUM> and in the embodiment shown in <FIG> is formed directly in the material of the longitudinal body <NUM>. In one embodiment the bottom wall or surface <NUM> is flat.

In one of the embodiments the blade of the cutting tool is the straight blade of the saw.

In addition to the longitudinal through hole <NUM>, the guide <NUM> has a set <NUM> of at least three through mounting holes <NUM>, <NUM>, <NUM> made in the body <NUM> of the guiding element <NUM> with a diameter not greater than <NUM>,<NUM> whose outlets <NUM>, <NUM>, <NUM> are located within the bottom wall or surface <NUM>, two of which are situated on one side of the longitudinal through hole or slit <NUM> and one is situated on an opposite side of a longitudinal axis <NUM> of symmetry of the through hole or slit <NUM> in relation to a side on which the two through mounting holes are located. Orthogonal projections <NUM>, <NUM> of the outlets <NUM>, <NUM> of the most distanced through mounting holes <NUM>, <NUM> from each other and situated on one side of the longitudinal through hole or slit <NUM> on the longitudinal axis <NUM> of symmetry of the through hole or slit <NUM> are located between opposite walls of the through hole or slit <NUM>. This means that the distance a between the through holes <NUM>, <NUM>, in particular between their centers, furthest apart and located on one side of the longitudinal through hole <NUM>, is less than the length b of the longitudinal through hole <NUM> and the through mounting holes <NUM>, <NUM> as viewed from a side, are located against the background of the longitudinal through hole <NUM>. The diameter of the mounting holes is not greater than <NUM>,<NUM>, in particular it is <NUM>,<NUM>.

In the embodiment shown in <FIG>, a guide <NUM> of a straight blade <NUM>, shown in fragments, for example, of an oscillatory saw, comprises a guiding element <NUM> whose body <NUM> has a shape of a solid fitting into a cuboid. The guiding element <NUM>, in particular in the central part, has a longitudinal through hole or a slit <NUM> having a width c not greater than <NUM>,<NUM> and a length b smaller than a longitudinal dimension of the body <NUM> of the guiding element <NUM>, except that compared to the embodiment shown in <FIG>, the longitudinal through hole <NUM> which in this embodiment is a hole <NUM> and which is perpendicular to a flat bottom wall or surface of the guiding element <NUM> and which is made in a metal cylindrical insert <NUM> embedded in a hole <NUM> made in the longitudinal body <NUM> and enlarged, in relation to the longitudinal through hole <NUM> shown in <FIG>, by the thickness of walls of the cylindrical insert <NUM>. The metal cylindrical insert <NUM> in one embodiment has a rectangular outer cross-sectional contour. The guiding element is made of metal, in particular of steel or cast steel, and a slider is made of steel. In other embodiments, the guiding element is made of plastic, and the cylindrical insert <NUM>, whose external shape and dimensions correspond to a shape of a hole made in the guiding element, is made of metal, in particular of steel or cast steel or other abrasion resistant material, which reduces the friction of the oscillatory saw against inner walls of the longitudinal through hole <NUM>.

As in the embodiment shown in <FIG> and <FIG>, the guide <NUM> has a set <NUM> of through mounting holes, in this case seven through mounting holes <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> made in the body <NUM> of the guiding element <NUM> with a diameter not greater than <NUM>,<NUM>, whose outlets are located within the bottom wall or surface. The holes <NUM>, <NUM>, <NUM>, <NUM> are situated on one side of the longitudinal through hole or slit <NUM>, and the holes <NUM>, <NUM>, <NUM> are situated on an opposite side of a longitudinal axis <NUM> of symmetry of the longitudinal through hole or slit <NUM> in relation to a side on which the through mounting holes <NUM>, <NUM>, <NUM>, <NUM> are located. The mounting holes in both embodiments are used to embed Kirschner nails in them when attaching the plate to the hip bone or ilium bone which stabilize the plate on the hip bone after installation which ensures the stability of the guide, enabling orthogonal cutting of the hip bone during osteotomy. The diameter of the mounting holes is not greater than <NUM>,<NUM>, in particular it is <NUM>,<NUM>.

The guide <NUM> of the straight blade <NUM> of the oscillatory saw in the embodiment shown in <FIG> furthermore has a transverse through hole <NUM> and a slider <NUM> with a stabilizing hole <NUM> with a diameter not greater than <NUM>,<NUM>, in particular <NUM>,<NUM>, situated at a free end of the slider <NUM>. The transverse through hole <NUM>, with a diameter or a side of <NUM>,<NUM> in one embodiment or <NUM>,<NUM> in another embodiment, is formed in the body <NUM> of the guiding element <NUM> and is located perpendicular to the longitudinal axis <NUM> of symmetry of the longitudinal through hole or slit <NUM>. The slider <NUM> is no longer than <NUM>,<NUM>, in particular <NUM>,<NUM> in one embodiment or <NUM>,<NUM> in another embodiment. The transverse through hole <NUM> acts as a guide for the slider <NUM> which is movably positioned within the transverse through hole <NUM>, for example with a sliding fit or with a loose fit. The cross section of the hole has a shape whose dimensions correspond to a shape and dimensions of a cross section <NUM> of the slider <NUM>, for example a circular shape <NUM> or a square shape <NUM>.

The guide <NUM> of the straight blade <NUM> of the oscillatory saw in the embodiment shown in <FIG>, additionally has in the body <NUM> of the guiding element <NUM> a threaded hole <NUM> with a diameter not greater than <NUM>,<NUM> that runs from an upper wall or surface <NUM> of the guiding element <NUM> to at least the transverse through hole <NUM> and in which a locking screw <NUM> is screwed in which when screwed into the threaded hole <NUM>, presses the slider <NUM> against the wall of the longitudinal through hole <NUM> and initially stabilizes the position of the guide <NUM> relative to the hip bone.

Yet another embodiment of the guide <NUM> according to the invention is shown in top view in <FIG>. Compared to the previously described guides, the guide <NUM> has recesses or indentations <NUM> in long side walls <NUM> of a body <NUM> of a guiding element <NUM>. In one embodiment, the recesses or indentations run perpendicularly to an upper wall or surface <NUM> of the body <NUM> of the guiding element <NUM> whose body <NUM> has the shape of a solid fitting into a cuboid. The guiding element <NUM>, in particular in the central part, has a longitudinal through hole or slit <NUM> having a width not greater than <NUM>,<NUM> and a length smaller than a longitudinal dimension of the body <NUM> of the guiding element <NUM>. The longitudinal through hole or slit <NUM> is perpendicular to the flat bottom wall or surface of the guiding element <NUM>. Similar to the embodiment shown in <FIG>, the guide <NUM> has a set <NUM> of through mounting holes, and similar to the embodiment shown in <FIG>, the guide <NUM> of a straight blade of an oscillatory saw of <FIG> and <FIG> has the transverse through hole <NUM> and a slider <NUM> with a stabilizing hole <NUM> located nearby its free end. The transverse through hole <NUM> is made in the body <NUM> of the guiding element <NUM> and is perpendicular to the longitudinal axis of symmetry of the longitudinal through hole or slit <NUM>. The guide <NUM> of the straight blade of the oscillatory saw in the embodiment shown in <FIG> has yet in the body <NUM> of the guiding element <NUM> the threaded hole <NUM>, shown in <FIG>, with the diameter not greater than <NUM>,<NUM> that runs perpendicularly from the upper wall or surface <NUM> of the guiding element <NUM> to at least the transverse through hole <NUM> and in which the locking screw <NUM> is screwed in which has a similar function as in the examples previously described.

<FIG> and <FIG> show the guide <NUM> attached to the hip bone or ilium bone prior to the surgery, for example an iliac shaft or diaphysis osteotomy performed as part of a corrective pelvic osteotomy in dogs. Although the following description will refer to the elements of the guide <NUM> shown in <FIG>, however, they may as well be the elements of the guides <NUM> and <NUM> and variants thereof.

In one embodiment, the set of mounting through holes has an even number of mounting holes forming two sub-sets of mounting holes with an equal number of mounting holes, whereas the sub-sets of mounting holes are located on opposite sides of the longitudinal through hole or slit <NUM>, <NUM>, <NUM>, and distances of holes from edges of the longitudinal through hole or slit <NUM>, <NUM>, <NUM> are the same.

The dimensions of the guiding element are usually adapted to the size of the hip bone of the operated animal. In one embodiment, the guiding element is a board with a thickness <NUM>,<NUM>, in another embodiment <NUM>,<NUM>, a width <NUM>,<NUM>, in another embodiment <NUM>,<NUM>, and in yet another embodiment <NUM>,<NUM>, and a length <NUM>,<NUM>, and in another embodiment <NUM>,<NUM>, and in yet another embodiment <NUM>,<NUM>. Given dimensions are also the dimensions of the guiding element shown in <FIG>, <FIG> and <FIG>. In all embodiments, the length b of the longitudinal through hole is at least <NUM>,<NUM> smaller than the length of the guiding element and the distance a between the extreme or furthest apart mounting holes is at least <NUM>,<NUM> smaller.

The guiding element is made of metal, in particular of steel or cast steel, and the slider is made of steel. In other embodiments, the guiding element is made of plastic and the insert is made of steel.

Claim 1:
A guide (<NUM>, <NUM>, <NUM>) of a saw blade (<NUM>) for double and triple pelvic osteotomies in dogs comprising a guiding element (<NUM>, <NUM>, <NUM>)
whose body (<NUM>, <NUM>, <NUM>) has a shape of a solid fitting into a cuboid and which has a longitudinal through hole or a slit (<NUM>, <NUM>, <NUM>) having a width c not greater than <NUM>,<NUM> and a length b smaller than a longitudinal dimension of the body (<NUM>, <NUM>, <NUM>) of the guiding element (<NUM>, <NUM>, <NUM>), whereby the through hole or slit (<NUM>, <NUM>, <NUM>) is perpendicular to a bottom wall or surface (<NUM>, <NUM>, <NUM>) of the guiding element (<NUM>, <NUM>, <NUM>)
and which has a set (<NUM>) of at least three through mounting holes (<NUM>, <NUM>, <NUM>) with a diameter not greater than <NUM>,<NUM> whose outlets (<NUM>, <NUM>, <NUM>) are located within the bottom wall or surface (<NUM>) of the guiding element (<NUM>, <NUM>, <NUM>), two of which are situated on one side of the longitudinal through hole or slit (<NUM>, <NUM>) and at least one is situated on an opposite side of a longitudinal axis (<NUM>) of symmetry of the through hole or slit (<NUM>, <NUM>) in relation to a side on which the two through mounting holes are located, whereas orthogonal projections (<NUM>, <NUM>) of the outlets (<NUM>, <NUM>) of most distanced through mounting holes (<NUM>, <NUM>) from each other and situated on one side of the longitudinal through hole or slit (<NUM>) on the longitudinal axis (<NUM>) of symmetry of the through hole or slit (<NUM>) are located between opposite walls of the through hole or slit (<NUM>)
characterised in that the guide has a slider (<NUM>, <NUM>) and in the body (<NUM>, <NUM>) of the guiding element (<NUM>, <NUM>) there is a transverse through hole (<NUM>) perpendicular to the longitudinal axis (<NUM>) of symmetry of the longitudinal through hole (<NUM>, <NUM>) with a cross-sectional shape and dimensions corresponding to a shape and dimensions of a cross-sectional profile of the slider (<NUM>, <NUM>) and the slider (<NUM>, <NUM>) is movably positioned within the transverse through hole (<NUM>) and has a stabilizing hole (<NUM>, <NUM>) nearby its free end and
has a locking screw (<NUM>) and in the body (<NUM>, <NUM>) of the guiding element (<NUM>, <NUM>) there is a threaded hole (<NUM>) that runs from an upper wall or surface (<NUM>, <NUM>) of the guiding element (<NUM>, <NUM>) to at least the transverse through hole (<NUM>) and in which a locking screw (<NUM>) is screwed in.