WO2005048888A1

WO2005048888A1 - A surgical procedure

Info

Publication number: WO2005048888A1
Application number: PCT/NZ2004/000296
Authority: WO
Inventors: James Burn
Original assignee: Enztec Limited
Priority date: 2003-11-21
Filing date: 2004-11-19
Publication date: 2005-06-02

Abstract

A method of preventing, treating and/or ameliorating the various deformities of the tibia of a human being, said method comprising the steps of (a) incompletely osteotomising (3) the bone of the tibia of the subject, distally and medially from below the inferolateral edge of the tibial tubercle, to the hinge point at the tibia flare superolaterally, (b) inserting a spacer (4) into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across osteotomy. Also disclosed is an implant (6) having a first region aperture (20) and a second region aperture (21) and a linking yet offsetting zone (22) between said first and second regions, the offsetting being in any axis.

Description

A SURGICAL PROCEDURE

FIELD OF THE INVENTION

This present invention relates to a system for performing proximal tibial osteotomies. The present invention also relates to related apparatus and kit and the use thereof in such surgical methodologies.

BACKGROUND

It is known that it is possible to correct certain bone-related problems by removal of a wedge of bone, or creation of wedge shape void, so as to realign the remaining segments thereof. This osteotomy technique can serve to bring anatomic and mechanical axes together at the joint for relief of gonarthritis, for example. This operation is usually traditionally performed adjacent the end of a bone, such as in the head of the tibia, without removing the end surface or entire head, as would be the case for preparation of the bone for implantation of a total joint prosthesis, such as a total knee prosthesis. Traditional methods of performing osteotomies such as the Coventry or Puddu medial proximal opening wedge technique (US5620448) can result in damage to the subchondral bone or condylar surfaces. The surgical methodologies presented in this disclosure reduce the risk of such damage occurring almost to a point of non-existence by moving the osteotomy site distally in relation to traditional sites. The Coventry technique causes damage to the normal tissues on the lateral side of the knee around the upper tibiofibular joint, and posterior tissue stripping causes increased risk of deep vein thrombosis. In addition, the osteotomys required when performing the Coventry technique are technically difficult and there is a requirement for X-ray control during surgery. The Coventry technique also damages the subchondral bone and deforms the proximal tibial making it difficult for later salvage surgery. The disadvantages with the Puddu medial proximal opening wedge technique are that it strips the soft tissues above the tibial tubercle causing patella baja (an abnormally low position of the patella), it requires osteotomys from the medial side of the tibia which strips posterior tissues such as veins, as well as requiring screws to be placed in the subchondral bone resulting in a stiffening of the natural shock absorption capacity of the bone. The Puddu plate results in poor stability, and the surgery requires X-ray control. Accordingly it is an object of the present invention to provide a surgical procedure that overcomes the aforementioned problems or at least will provide the public with a useful choice. As used herein the term "osteotomising" and "osteotomy" relates to any procedure that leads to cutting of biological material such as bone.

BRIEF DESCRIPTION OF THE INVENTION

In the first aspect the present invention consists of a method of preventing, treating and/or ameliorating complications of the leg used singularly or in conjunction with other surgical methodologies in a human being (hereafter "subject"), said method comprising or including the following steps: (a) incompletely osteotomising the bone of the tibia of the subject, distally and medially from below the inferolateral edge of the tibial tubercle, to the hinge point at the tibia flare superolaterally, (b) inserting a spacer into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across the osteotomy. In a second aspect the present invention consists in a method of preventing, treating and/or ameliorating the various deformities of the tibia of a human being (hereafter "subject"), said method comprising or including the following steps: (a) incompletely osteotomising the bone of the tibia of the subject, distally and medially from below the inferolateral edge of the tibial tubercle, to the hinge point at the tibia flare superolaterally, (b) inserting a spacer into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across the osteotomy. In a further and alternative aspect the present invention is directed to a surgical methodology of correctional surgery of the tibia that can be combined with uni- knee hemiarthroplasty of a human being (hereafter "subject"), said method including or comprising the following steps: (a) incompletely osteotomising the bone of the tibia of the subject, distally and medially from below the inferolateral edge of the tibial tubercle, to the hinge point at the tibia flare superolaterally, (b) inserting a spacer into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across the osteotomy. In still a further and alternative aspect the present invention is directed to a surgical methodology of correctional surgery of the tibia that can be combined with anterior cruciate ligament (ACL) reconstruction of a human being (hereafter "subject"), said method including or comprising the following steps: (a) incompletely osteotomising the bone of the tibia of the subject, distally and medially from below the inferolateral edge of the tibial tubercle, to the hinge point at the tibia flare superolaterally, (b) inserting a spacer into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across the osteotomy. In another aspect the present invention consists in a method of unloading the medial compartment of the knee of a human being (hereafter "subject"), said method comprising or including the following steps: (a) incompletely osteotomising the bone of the tibia of the subject, distally and medially from below the inferolateral edge of the tibial tubercle, to the hinge point at the tibia flare superolaterally, (b) inserting a spacer into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across the osteotomy. In a further aspect the present invention consists of a method of preventing, treating and/or ameliorating complications of the leg used singularly or in conjunction with other surgical methodologies in a human being (hereafter

"subject"), said method comprising or including the following steps: (a) osteotomising the bone of the tibia of the subject, by cutting along a path between a point distally and medially to the inferolateral edge of the tibial tubercle, and a point inferomedial to the tibial flare, wherein said osteotomising of bone is incomplete leaving a hinging portion of lateral cortex, (b) inserting a spacer into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across the osteotomy. As used herein indication as to the orientation of the osteotomy by reference to its orientation as distally and medially of the tibia tubercle to the tibia flare superolaterally does not indicate a preferred direction of cutting nor indicate any preference as to the path of the osteotomy line (i.e. could be a straight line, angled, an arc etc). In another aspect the present invention consists in a method of preventing, treating and/or ameliorating the various deformities of the tibia of a human being (hereafter "subject"), said method comprising or including the following steps: (a) osteotomising the bone of the tibia of the subject, by cutting along a path between a point distally and medially to the inferolateral edge of the tibial tubercle, and a point inferomedial to the tibial flare, wherein said osteotomising of bone is incomplete leaving a hinging portion of lateral cortex, (b) inserting a spacer into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across the osteotomy. In another aspect the present invention consists in a method of unloading the medial compartment of the knee of a human being (hereafter "subject"), said method comprising or including the following steps: (a) osteotomising the bone of the tibia of the subject, by cutting along a path between a point distally and medially to the inferolateral edge of the tibial tubercle, and a point inferomedial to the tibial flare, wherein said osteotomising of bone is incomplete leaving a hinging portion of lateral cortex, (b) inserting a spacer into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across the osteotomy. In a further and alternative aspect the present invention is directed to a surgical methodology of correctional surgery of the tibia that can be combined with uni- knee hemiarthroplasty of a human being (hereafter "subject"), said method including or comprising the following steps: (a) osteotomising the bone of the tibia of the subject, by cutting along a path between a point distally and medially to the inferolateral edge of the tibial tubercle, and a point inferomedial to the tibial flare, wherein said osteotomising of bone is incomplete leaving a hinging portion of lateral cortex, (b) inserting a spacer into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across the osteotomy. In still a further and alternative aspect the present invention is directed to a surgical methodology of correctional surgery of the tibia that can be combined with anterior cruciate ligament (ACL) reconstruction of a human being (hereafter "subject"), said method including or comprising the following steps: (a) osteotomising the bone of the tibia of the subject, by cutting along a path between a point distally and medially to the inferolateral edge of the tibial tubercle, and a point inferomedial to the tibial flare, wherein said osteotomising of bone is incomplete leaving a hinging portion of lateral cortex, (b) inserting a spacer into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across the osteotomy. In one embodiment the line of osteotomy is in a straight line between said two end points, said end points being a point distally and medially below the inferolateral edge of the tibial tubercle, and a point superolaterally to the tibia flare. Preferably the said method is performed in the proximal region of the said tibia. Preferably the osteotomy of the proximal bone is from one side of the bone towards or to the opposite side of the tibial bone. Preferably the osteotomy is cut from the front through the posterior cortex starting medially. Preferable the osteotomy is made at an angle of 45° to 60° distally and medially from the inferolateral edge of the tibial tubercle. Preferably the lateral cortex of the proximal tibia is not cut. Preferably the osteotomy is opened by a wedge, or controlled levering spreading said osteotomy. Preferably the opened osteotomy has a spacer placed therein. Preferably that spacer is shaped as a wedge. Preferably the spacer is a bone grafted from the subject. Preferably the wedge consists of at least one tri-cortical graft. Preferably the tri-cortical graft can slide up or down the osteotomy to adjust the angle size of the osteotomy. Preferably the implant is a plate or other suitable device. In a further embodiment the present invention consists of a surgical implant, whetlier planar or not, (hereafter referred to as a "plate"), said implant being formed form one or more biocompatible materials, the implant having a first region aperture to be affixed by penetrative fasteners to and against the tibia, a second region aperture to be affixed by penetrative fasteners to and against the tibia, and a linking yet offsetting zone between said first and second regions customising for an offset that may be appropriate, or an appropriate starting point for further manipulation, of the relativities of the first and second regions for a particular patient, the offsetting being in any axis. In one embodiment the relationship of said first and second regions is as the top and bottom of the stem of a T-form, and said offsetting can be into the plane of the T- form or in the plane of the T-form or both. Preferably the aperture placement is collectively to provide at least a triangulation. Preferably the extent that each of the first and second regions can be considered as substantially planar, such general planes are substantially parallel or coincident. Preferably said plate or other device is of a suitable metal, synthetic or ceramic material that is biocompatible. Preferably the contour of the implant is tailored to suit the profile of the underlying bone and associated protrusions. Preferably said plate is moulded to fit the contours of the tibia.

Preferably the length of the implant is such that it aids in supporting the affected bone stock. Preferably the plate also has sufficient strength to carry the loads applied to the affected bone. In one embodiment the plate is pre-contoured and profiled to suit the generic form of the target osteotomy site. In one embodiment the plate is produced from a malleable material which is able to accept additional contouring by the osteotomy surgical procedure. In one embodiment said plate may include chemical, medicated or mechanical surface treatments to promote or prevent biological adherence or for the treatment of conditions. In one embodiment said plate is characterised by having straight fixation stems. In an alternate embodiment said plate is characterised by being pre-contoured. Preferably said plate is pre-contoured with sharp bends although such pre-contours may take other forms however. Preferably the plate has holes to allow the use of fasteners to fasten the plate to the bone. Preferably the fasteners allow the plate to secure the osteotomy into the bone. Preferably the fasteners are aligned as to provide a triangulated fixer to prevent any movement of the affixed surfaces in relation to each other. Preferably the fasteners are screws. Preferably the fasteners are attached to cortical bone and not subchondral bone. In one embodiment holes for said fasteners at the superior end of the plate are positioned above the open osteotomy wedge site in a triangular fashion. Preferably said fasteners at the inferior end of the plate are positioned below the open osteotomy wedge site. The position and number of fastener holes may be varied to optimise the fastening of the fixation device to the underlying bone. The edge or surface profile of a plate may vary along the length of said plate. Some embodiments of said profile include a square corner profile, a tapered edge profile, a radiused edge profile, or a relieved edge or face profile. Preferably said holes in said plate for said fasteners are recessed. Some different embodiments of the shape of the recess include square corner profiles to accommodate standard screws, tapered profiles, threaded head profiles, such as those used on fixed angle or locking screw designs, spherical recessed head profiles, such as those used to accommodate screws which can be offset through angles relative to the plate. In one embodiment the edges of the plate may also be contoured in conjunction with different screw head recesses, for example the top surface or edge of the plate may be relieved and the fastener hole recessed. As used herein triangulation includes fixing by two spaced apertures on one axis and holding relative to that axis with at least one apertures of the other region. This invention may also be said broadly to consist on the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more said parts, elements or features, and where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.

BRIEF DESCRIPTION OF THE DRAWINGS

One preferred procedure of the present invention will now be described with reference to the accompanying drawings in which: Figure 1 is a pre-surgical anterior view of the knee and tibia showing the line of the incision to be made in order to produce the osteotomy, Figure 2 is an anterior view of the knee and tibia showing the line of the incision made in the tibia to produce an osteotomy, Figure 3 is an anterior view of the proximal tibia showing the use of a surgeons wedge to separate the medial proximal and distal surfaces of the osteotomised tibia, Figure 4 is an anterior view of the knee and tibia showing insertion of wedges within the osteotomy of the tibia, Figure 5 is an anterior view of the knee and tibia showing the fixation of an implant over the line of the osteotomy, Figure 6 shows the high tibial osteotomy (HTO) plate which is made of

BiodurTM stainless steel or titanium, Figure 7 is a plan view of one embodiment of a HTO plate, Figure 8 is a side view of one embodiment of HTO plate, Figure 9 is a front view of one embodiment of an HTO plate, Figure 10 is a front view of one embodiment of an HTO plate, Figure 11 is shows a series of section views with alternative edge profiles, Figure 12 is shows a series of section views with alternative fastener hole forms, Figure 13 is an anterolateral view of the femur, tibia and fibia showing the positioning of the implant and the use of fasteners to attach it to the tibia, Figure 14 is a post-operative view of the affected leg with subcuticular closure with a suction drain, and Figure 15 is a post-operative view of the affected leg showing application of a gentle pressure dressing.

DETAILED DESCRIPTION OF THE INVENTION

The method of performing an opening wedge osteotomy in accordance with the present invention will now be described: 1. The patient is prepped and the surgical site and ipsilateral hip are steri- draped. 2. A high thigh padded tourniquet is applied to the leg to be operated upon. 3. With reference to Figure 1, the anticipated antero-medial osteotomy is shown as 1, which is positioned medially and distally from 2, the inferolateral edge of the tibial tubercle 16. This osteotomy of the bone follows a preferably corresponding opening of the soft tissue over the bone without disruption of the surrounding ligaments such as the tibial collateral ligament, the fibular collateral ligament or the pes anserinus. Additionally, the placement of the osteotomy prevents interference of the peroneal and upper tibiofibular joint. 4. With reference to Figure 2, following the osteotomy of the soft tissue above the tibial bone to be osteotomised, an osteotomy is made through the tibia 8 resulting in a cut through the anterior portion of the tibia as shown by 3. This cut extends through the posterior cortex leaving a bony hinge on the lateral side, in cortico- cancellous bone. 5. With reference to Figure 3, the osteotomy 3 is wedged open by any appropriate wedging tool 10 to allow the insertion of spacers 4. 6. With reference to Figure 4, to determine the angle of tibial correction, a diathermy cord 13 is used in a straight line from the centre of the femoral head (2 finger breadths inside the anterior superior iliac spine [ASIS ]), to the midpoint of the ankle. The opening of the osteotomy can be adjusted so that the weight bearing line passes just into the lateral compartment of the superior articular surface of the tibia. 7. With reference to Figure 4 grafts are cut from the iliac crest to be used as spacers 4 to fit into the osteotomy 3. The use of a bone graft from the iliac crest allows good osteosynthesis. The spacers 4 allow infinite adjustability of the opening of the osteotomy 3 as they can be slid up or down the osteotomy (medial to lateral) in order to obtain the correct angle of tibial alignment. 8. With reference to Figure 5, once the spacers 4 have been fitted to the osteotomy the vertical alignment of the tibia is secured by an implant 6, such as that shown in Figure 6, by the use of fasteners 7 into the cortex of the tibia 8. Preferably the fasteners are placed through the cortical bone thereby preventing any damage to subchondral bone. The implant, such as a HTO plate 6 shown in Figure 6 has round holes 11 that are recessed for screws heads and would prevent shortening. The plate has a smooth profile and is easily contoured to the shape of the tibia. 9. With reference to Figure 13, the implant 6 is shown secured to the tibia 8 by fasteners 7 to enable a correct alignment of the tibia as shown by 9. The implant, such as an HTO plate 6, has features which are unique and novel to suit the open wedge osteotomy site. The contour of the fixation plate is tailored to suit the profile of the underlying bone and associated protrusions. The length of the plate is such that it aids in supporting the affected bone stock. The plate also has sufficient strength to carry the loads applied to the affected bone. To improve the load carrying performance, reduce operator stress, and limit the effects on the surrounding soft tissues the plate can be pre-contoured and profiled to suit the generic form of the target osteotomy site. To compliment this pre-contouring, the plate is produced from a malleable material which is able to accept additional contouring by the osteotomy surgical procedure. The location of the fasteners, associated with the implant, can also be tailored to suit the underlying bone thus allowing the surgical operating staff to place fasteners into bone stock with appropriate properties. Specifically in the case of an open wedge tibia osteotomy the fasteners should ideally be located in cortical bone rather than the subchondral bone, failure to achieve this may result in stiffening of the subchondral bone stock and which may in turn result in damage of the patient's knee joint. Figure 7 shows a plan view of an implant in the form of an HTO plate. This view shows the plate in one form where it is contoured to fit the radial profile of a long bone, such as a tibia. The plate may also feature chemical, medicated or mechanical surface treatments on the bone contact face 16 and the outer face 17 to promote or prevent biological adherence or for the treatment of conditions. Figure 8 shows the side profile of one embodiment of an implant, in the form of an HTO plate. This diagram shows two potential methods of pre-contouring the implant to suit the profile of the underlying bone through the use of sharp bends 18 or radial bends 19. Figure 9 and Figure 10 show front views of one embodiment of an implant, in the form of an HTO plate, with a straight fixation stems and an alternative pre- contoured form with sharp bends 22, such pre-contours may take other forms however. An example distribution of fastener holes 11 is also shown, the fastener holes at the superior end of the plate 20 would typically be positioned above the open osteotomy wedge site in a triangular fashion, while the inferior fastener holes 21 would typically be positioned below the open osteotomy wedge site. The position and number of fastener holes 11 may also be varied to optimise the fastening of the fixation device to the underlying bone. When generating the profiles illustrated in Figures 7 to 10 due consideration would also have to be given to ensure the impant had sufficient strength and length to carry the applied loads in a stable manner. Figure 11 is shows a series of section views with alternative edge profiles. In this figure the implant is shown without additional contouring such as that shown in Figures 7-10. Such edge or surface profile of the fixation device may vary along the length of the device. Some examples of generic profiles that may be used include a square corner profile 23, a tapered edge profile 24, a radiused edge profile 25, or a relieved edge or face profile 26. Figure 12 is shows a series of section views with alternative fastener hole 11 forms. In this figure the implant is shown without additional contouring such as that shown in Figures 7-10. These alternative hole profiles may be used to engage with different screw head designs. Some examples of generic hole profiles include square corner profiles 27 to accommodate standard screws, tapered profiles 28, threaded head profiles 29 such as those used on fixed angle or locking screw designs, spherical recessed head profiles 30 such as those used to accommodate screws which can be offset through angles relative to the HTO plate 6. The edges of the plate may also be contoured in conjunction with different screw head recesses, for example the top surface or edge of the plate may be relieved and the fastener hole recessed 31. 10. The wound is closed over a suction drain 14 with antibiotics for 24 hours as shown in Figure 14. A gentle pressure dressing 15 is applied as shown in Figure 15 and no bracing is required. 11. During post-operative rehabilitation weight bearing is allowed on the subjects affected leg as comfort dictates. Within 12 hours, quadricep and knee motion exercises are started. The present invention provides an alternative to the prior art procedures discussed previously. Particular advantages of the procedure are as follows: 1. this method does not result in the violation of the knee joint or associated ligaments, tendons and blood supply, 2. no form of bracing, such as a cast, is required, 3. there is no posterior soft tissue stripping, 4. osteotomy is infinitely adjustable due to the opening wedge, 5. there is no need for radiological intra-operative screening, 6. and the medial joint space of the articular surface of the tibia is not tightened. 7. the fixation is to the cortical bone giving good fix but the 'pivot' of the osteotomy is close to the uppertibiofibular joint, 8. The proximal tibial bone is minimally violated allowing the oestomy to be easily combined with other procedures around the knee (ACL reconstruction, Hemiknee replacement),

9. the incision used is an extension of that used for total knee replacement.

10. using the technique disclosed in this document also offers the advantage of only altering the coronal axis of the tibia, without also introducing the secondary side effect of loss of sagittal alignment, this helps to preserve normal loading and alignment of the hip and knee joints.

Claims

1. A method of preventing, treating and/or ameliorating complications of the leg used singularly or in conjunction with other surgical methodologies in a human being (hereafter "subject"), said method comprising or including the following steps: (a) incompletely osteotomising the bone of the tibia of the subject, distally and medially from below the inferolateral edge of the tibial tubercle, to the hinge point at the tibia flare superolaterally, (b) inserting a spacer into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across the osteotomy.

2. A method of preventing, treating and/or ameliorating the various deformities of the tibia of a human being (hereafter "subject"), said method comprising or including the following steps: (a) incompletely osteotomising the bone of the tibia of the subject, distally and medially from below the inferolateral edge of the tibial tubercle, to the hinge point at the tibia flare superolaterally, (b) inserting a spacer into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across the osteotomy.

3. A surgical methodology of correctional surgery of the tibia that can be combined with uni-knee hemiarthroplasty of a human being (hereafter "subject"), said method including or comprising the following steps: (a) incompletely osteotomising the bone of the tibia of the subject, distally and medially from below the inferolateral edge of the tibial tubercle, to the hinge point at the tibia flare superolaterally, (b) inserting a spacer into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across the osteotomy.

4. A surgical methodology of correctional surgery of the tibia that can be combined with anterior cruciate ligament (ACL) reconstruction of a human being (hereafter "subject"), said method including or comprising the following steps: (a) incompletely osteotomising the bone of the tibia of the subject, distally and medially from below the inferolateral edge of the tibial tubercle, to the hinge point at the tibia flare superolaterally, (b) inserting a spacer into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across the osteotomy.

5. A method of unloading the medial compartment of the knee of a human being (hereafter "subject"), said method comprising or including the following steps: (a) incompletely osteotomising the bone of the tibia of the subject, distally and medially from below the inferolateral edge of the tibial tubercle, to the hinge point at the tibia flare superolaterally, (b) inserting a spacer into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across the osteotomy.

6. A method of preventing, treating and/or ameliorating complications of the leg used singularly or in conjunction with other surgical methodologies in a human being (hereafter "subject"), said method comprising or including the following steps: (a) osteotomising the bone of the tibia of the subject, by cutting along a path between a point distally and medially to the inferolateral edge of the tibial tubercle, and a point inferomedial to the tibial flare, wherein said osteotomising of bone is incomplete leaving a hinging portion of lateral cortex, (b) inserting a spacer into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across the osteotomy.

7. A method of preventing, treating and/or ameliorating the various deformities of the tibia of a human being (hereafter "subject"), said method comprising or including the following steps: (a) osteotomising the bone of the tibia of the subject, by cutting along a path between a point distally and medially to the inferolateral edge of the tibial tubercle, and a point inferomedial to the tibial flare, wherein said osteotomising of bone is incomplete leaving a hinging portion of lateral cortex, (b) inserting a spacer into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across the osteotomy.

8. A method of unloading the medial compartment of the knee of a human being (hereafter "subjecf), said method comprising or including the following steps: (a) osteotomising the bone of the tibia of the subject, by cutting along a path between a point distally and medially to the inferolateral edge of the tibial tubercle, and a point inferomedial to the tibial flare, wherein said osteotomising of bone is incomplete leaving a hinging portion of lateral cortex, (b) inserting a spacer into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across the osteotomy.

9. A surgical methodology of correctional surgery of the tibia that can be combined with uni-knee hemiarthroplasty of a human being (hereafter "subject"), said method including or comprising the following steps: (a) osteotomising the bone of the tibia of the subject, by cutting along a path between a point distally and medially to the inferolateral edge of the tibial tubercle, and a point inferomedial to the tibial flare, wherein said osteotomising of bone is incomplete leaving a hinging portion of lateral cortex, (b) inserting a spacer into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across the osteotomy.

10. A surgical methodology of correctional surgery of the tibia that can be combined with anterior cruciate ligament (ACL) reconstruction of a human being (hereafter "subject"), said method including or comprising the following steps: (a) osteotomising the bone of the tibia of the subject, by cutting along a path between a point distally and medially to the inferolateral edge of the tibial tubercle, and a point inferomedial to the tibial flare, wherein said osteotomising of bone is incomplete leaving a hinging portion of lateral cortex, (b) inserting a spacer into said osteotomy, and (c) stabilising the osteotomised tibia by the securement of an implant to the tibia across the osteotomy.

11. A method of any one of claims 1 to 10 where the line of osteotomy is in a straight line between said two end points, said end points being a point distally and medially below the inferolateral edge of the tibial tubercle, and a point superolaterally to the tibia flare.

12. A method of any one of claims 1 to 11 where the methodology is performed on the proximal region of the said tibia.

13. A method of any one of claims 1 to 12 where the osteotomy of the proximal bone is performed from one side of the bone towards or to the opposite side of the tibial bone.

14. A method of any one of claims 1 to 13 where the osteotomy is cut from the front through the posterior cortex starting medially.

15. A method of any one of claims 1 to 14 where the osteotomy is made at an angle of 45° to 60° distally and medially from the inferolateral edge of the tibial tubercle.

16. A method of any one of claims 1 to 15 where the lateral cortex of the proximal tibia is not cut.

17. A method of any one of claims 1 to 16 where the osteotomy is opened by a wedge, or controlled levering, resulting in the spreading of the osteotomy.

18. A method of any one of claims 1 to 17 where said spacer is wedge-shaped.

19. A method of any one of claims 1 to 18 where the spacer is a bone grafted from the subject.

20. A method of any one of claims 1 to 19 where the spacer consists of at least one tri-cortical graft.

21. A method of claim 20 where the tri-cortical graft can slide up or down the osteotomy to adjust the angle size of the osteotomy.

22. A method of any one of claims 1 to 21 where the implant is a plate or other suitable device.

23. A surgically implantable plate for use in a surgical procedure of any one of claims 1 to 22.

24. A plate of claim 23 where said plate is of a suitable metal, synthetic and/or ceramic material that is biocompatible.

25. A plate of claim 23 or 24 where the contour of the plate is tailored to suit the profile of the underlying bone and associated protrusions.

26. A plate of claim 25 wherein the plate is moulded to fit the contours of the tibia.

27. A plate of any one of claims 23 to 26 wherein said plate is made out of material that allow it to accept additional contouring by the osteotomy surgical procedure.

28. A plate of any one of claims 23 to 27 where the plate is pre-contoured.

29. A plate of claim 28 wherein said pre-contouring is in the form of bends applied to said plate.

30. A plate of claim 28 or 29 where the pre-contouring may occur around a single axis or combination of axes to give the desired shape.

31. A plate of any one of claims 23 to 30 where the length of the plate is such that it aids in supporting the affected bone stock.

32. A plate of any one of claims 23 to 31 where the plate has sufficient strength to carry the loads applied to the affected bone.

33. The plating system of any one of claims 23 to 32 where the device may incorporate surface treatments, which may include none, one or several of the following embodiments: (i) surface treatments with the aim of promoting bone growth, (ii) surface treatments to promote or discourage bone adherence, or (iii) surface treatments which aid in the treatment of other disorders.

34. A plate of any one of claims 23 to 33 the plate has holes to allow the use of fasteners to fasten the plate to the bone.

35. A plate of any one of claims 23 to 34 wherein said plate has fasteners that allow the plate to secure the osteotomy into the bone.

36. A plate of claim 34 or 35 where there are single or multiple fasteners above and below the osteotomy site.

37. A plate of any one of claims 34 to 36 wherein said fasteners are aligned so as to provide a triangulated fixer (i.e. to the bone) to prevent any movement of the affixed surfaces in relation to each other.

38. A plate of any one of claims 34 to 37 the fasteners are attached to cortical bone and not subchondral bone.

39. A plate of any one of claims 23 to 38 wherein said plate has fastener holes located at both the superior and inferior ends of the plate.

40. A plate of claim 39 wherein said fastener holes at the superior end of the plate are positioned above the open osteotomy wedge site in a triangular fashion.

41. A plate of either claim 38 or 40 wherein said fasteners holes at the inferior end of the plate are positioned below the open osteotomy wedge site.

42. A plate of any one of claims 23 to 41 wherein the edge or surface profile of said plate may vary along the length of said plate.

43. A plate of claim 42 wherein said profile is selected from either a square corner profile, a tapered edge profile, a radiused edge profile, or a relieved edge or face profile.

44. A plate of any one of claims 34 to 43 wherein said fastener holes are recessed.

45. A plate of claim 44 where the heads of the fasteners are positioned in the plate such that they are flush with the surface of the plate or recessed below the surface of the plate.

46. A plate of claim 44 or 45 wherein the shape of said recessed fastener hole is selected from one of either a square-form profile, tapered profile, threaded head profiles (such as those used on fixed angle or locking screw designs), spherical recessed head profiles, such as those used to accommodate screws which can be offset through angles relative to the plate.

47. A plate of any one of claims 23 to 46 wherein the edges of the plate are contoured in conjunction with the screw head recesses.

48. A plate of claim 47 wherein the top surface or edge of the plate is relieved and the fastener hole recessed.

49. A plate of any one of claims 32 to 48 the fasteners are screws.

50. A plate of claim 49 where said screws characterised by being: (i) flat, spherical, tapered or elliptical which engage with corresponding recesses in the plate; (ii) able to engage with pre-cut threads in the plate; (iii) able to form and engage with threads in the plate;

51. able to be displaced angularly relative to the plate so they may or may not be perpendicular to the surface of the plate.

52. A plate of any one of claims 23 to 50 which incorporates profile and/or cross section shaping to facilitate easier insertion or to accommodate soft tissues, this may include one or several of the following embodiments: (i) the distal end of the device may have a pointed profile; (ii) the thickness of the device may be reduced in a tapering or radial manner along whole or partial edges; (iii) the surface of the fixation device may be reduced in thickness in a regular or irregular fashion.

53. A method as described in any one of claims 1 to 22 in conjunction with a plate as claimed in any one of claims 23 to 51.

54. A surgically implantable plate substantially as depicted in reference to any one or more of the drawings herein.

55. A surgical implant, whether planar or not, (hereafter referred to as a "plate"), said implant being formed form one or more biocompatible materials, the implant having a first region aperture to be affixed by penetrative fasteners to and against the tibia, a second region aperture to be affixed by penetrative fasteners to and against the tibia, and a linking yet offsetting zone between said first and second regions customising for an offset that may be appropriate, or an appropriate starting point for further manipulation, of the relativities of the first and second regions for a particular patient, the offsetting being in any axis.

56. An implant as claimed in claim 55 where in the relationship of said first and second regions is as the top and bottom of the stem of a T-form, and said offsetting can be into the plane of the T-form or in the plane of the T-form or both.

57. An implant of claim 55 or 56 wherein the aperture placement is collectively to provide at least a triangulation.

58. An implant as claimed in one of claims 55 to 57 wherein to the extent that each of the first and second regions can be considered as substantially planar, such general planes are substantially parallel or coincident.