FORM 2
THE PATENTS ACT, 1970 (39 OF1970)
&
THE PATENTS RULES, 2003
COMPLETESPECIFICATION
[SEE SECTION 10, RULE 13]
INTERLOCKING FEMORAL AUGMENTS
APPLICANT:
BIORAD MEDISYS PRIVATE LIMITED
ANINDIANCOMPANYHAVING OFFICE ADDRESS AT
Survey No. 48, 3 & 48 7, Pashan - Sus Rd, Sus, Pune, Maharashtra 411021
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE SUBJECT MATTER AND THE MANNER IN WHICH IT IS TO BE PERFORMED

TECHNICAL FIELD
[0001] The present subject matter relates generally to orthopaedic
instruments for use in the performance of an orthopaedic joint replacement procedure and more particularly to bone augmenting member used to reinforce damaged bone encountered during joint arthroplasty procedures.
BACKGROUND
[0002] Knee replacement surgery methods and knee joint prostheses
are known in the art. Knee prostheses may include a femoral component implanted on the distal end of the femur, which articulates with a tibial component implanted on the proximal end of a tibia to replicate the function of a healthy natural knee. When the knee joint is damaged whether as a result of an accident or illness, a prosthetic replacement of the damaged joint may be necessary to relieve pain and to restore normal use to the joint. Typically, the entire knee joint is replaced by means of a surgical procedure that involves removal of the surfaces of the corresponding damaged bones and replacement of these surfaces with prosthetic implants. This replacement of a native joint with a prosthetic joint is referred to as a primary total-knee arthroplasty.
[0003] On occasion, the primary knee prostheses fail. Failure can result
from many causes, including wear, aseptic loosening, osteolysis, ligamentous instability, arthrofibrosis and patellofemoral complications. When the failure is debilitating, revision knee surgery may be necessary. In a revision, the primary knee prosthesis is removed and replaced with components of a

revision prosthetic knee system. In certain situations, additional portions of the femur, other than the relatively narrow distal portion being removed during knee replacement surgery, may also be damaged by, for example, loss of bone from prior procedures. In such situations, a relatively thick distal portion of the femur is often removed, and it is replaced with an augment block or a wedge-shaped augment shaped like the bone that has been removed. However, such previously known methods often result in the removal of an unnecessary amount of healthy bone along with the damaged bone. Thus, for example, even in cases where the peripheral bone was healthy, and only the internal bone was damaged, prior art methods often removed both the healthy peripheral bone and the damaged internal bone.
[0004] Prosthetic knee implant systems have commonly included
femoral augments for use on the distal and posterior bone-facing surfaces of the femoral implant components. Such components serve to augment the inferior and posterior portions of the femoral component to add additional thickness to compensate for the lack of sufficient boney tissue, allowing the joint line to be distalized. Augmentation of the boney mass can be accomplished by securing augmenting devices to a component of the joint prosthesis, such as a femoral component. Some earlier devices used to augment knee femoral components must be cemented to the inferior surface of the femoral component. The techniques used to install such devices require accurate measurements and a great deal of precision since the augmenting device is difficult, if not impossible, to remove once it is secured to the prosthesis. These techniques also tend to be rather time consuming.
[0005] Despite existing augmentation systems, there remains a need to
provide improved systems that allow standard augmenting components to

be easily and securely affixed within a prosthesis component. The cost of joint prostheses that utilize many current augmentation systems can be quite high because the tight tolerances required often result in a high scrap rate. There is thus a need for an augmentation system that allows augmenting devices to be easily and securely fitted to prosthesis components.
[0006] This invention is therefore directed towards providing an
improved augmentation system, which is relatively simple in design and structure, and is highly effective for its intended purpose.
SUMMARY
[0007] Embodiments of the present disclosure present technological
improvements as solutions to one or more of the above-mentioned technical problems.
[0008] Before the present subject matter relating to an Interlocking
Femoral Augments, it is to be understood that this application is not limited to the particular system(s) and methodologies described, as there can be multiple possible embodiments which are not expressly illustrated in the present disclosure. It is also to be understood that the terminology used in the description is for the purpose of describing the implementations or versions or embodiments only and is not intended to limit the scope of the present subject matter.
[0009] This summary is provided to introduce aspects related to an
Interlocking Femoral Augments. This summary is not intended to identify

essential features of the claimed subject matter nor is it intended for use in determining or limiting the scope of the present subject matter.
[0010] An object of the present invention is to provide a prosthesis
augmentation system that securely and easily fits within a component of a joint prosthesis.
[0011] Another object of the present invention is to provide an
augmentation system that is well suited for use with femoral components of knee joint prostheses.
[0012] Yet another object of the invention is to provide an
augmentation system that offers a great deal of versatility in that it can be used with different types of femoral components.
[0013] In an aspect of the present disclosure, Interlocking Femoral
Augments system is disclosed. The system consists of a distal femoral augment and a posterior femoral augment, both with predetermined thicknesses, as well as a femoral prosthesis. These components are engineered to interlock through primary and secondary locking mechanisms, effectively preventing rotation within the augments and dislocation of the augments with the femoral prosthesis. The distal femoral augment compensates for bone defect volume on the distal flange of the prosthesis, while the posterior femoral augment addresses defects on the posterior flange. The system offers various augment thickness options and features, such as pockets for cementing and protrusions for interlocking. The primary locking mechanism involves screws, while the secondary mechanism utilizes

cementing for secure augmentation attachment and prevent dislocation of augments within femoral component.
[0014] Additional aspects, advantages, features and objects of the
present disclosure would be made apparent from the drawings and the detailed description of the illustrative embodiment.
[0015] It will be appreciated that features of the present disclosure are
susceptible to being combined in various combinations without departing from the scope of the present disclosure as defined by the below mentioned detailed description and drawings.
BRIEF DESCRIPTION OF THE FIGURES
[0016] The summary above, as well as the following detailed
description of illustrative embodiment, is better understood when read in conjunction with the appended drawings. For illustrating the present disclosure, example constructions of the disclosure are shown in the drawings. However, the present disclosure is not limited to specific methods and instrumentalities disclosed herein. Moreover, those in art will understand that the drawings are not to scale.
[0017] Embodiment of the present disclosure will now be described, by
way of example only, with reference to the following diagrams wherein:
[0018] Fig 1. Illustrates an Interlocking Femoral Augment System, in
accordance with an embodiment of the present subject matter.

[0019] Fig. 2(a) and 2(b) illustrates a perspective view of the Posterior
Femoral Augments in accordance with an embodiment of the present subject matter.
[0020] Fig. 3(a) and 3(b) illustrates a perspective view of the Distal
Femoral Augments in accordance with an embodiment of the present subject matter.
[0021] Fig.4(a) and 4(b) illustrates a perspective view of Femoral
Prosthesis in accordance with an embodiment of the present subject matter.
[0022] Fig.5(a) and 5(b) illustrates a perspective view of Screws in
accordance with an embodiment of the present subject matter.
[0023] In the above accompanying drawings, a number relates to an
item identified by a line linking the number to the item. When a number is accompanied by an associated arrow, the number is used to identify a general item at which the arrow is pointing.
[0024] Further the figures depict various embodiment of the present
subject matter for purposes of illustration only. One skilled in the art will readily recognize from the following discussion that alternative embodiment of the structures and methods illustrated herein may be employed without departing from the principles of the present subject matter described herein.

DETAILED DESCRIPTION OF EMBODIMENTS
[0025] The following detailed description illustrates embodiment of the
present disclosure and manners by which they can be implemented. The words "comprising," "having," "containing," and "including," and other forms thereof, are intended to be equivalent in meaning and be open ended in that an item or items following any one of these words is not meant to be an exhaustive listing of such item or items, or meant to be limited to only the listed item or items. It must also be noted that as used herein and in the appended claims, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise.
[0026] The person skilled in the art will recognize many variations,
alternatives, and modifications of the embodiment of the present disclosure. It should be understood that this invention is not limited to the particular methodology, protocols, and the like, described herein and as such may vary. The terminology used herein is for the purpose of describing particular embodiment only and is not intended to limit the scope of the present invention, which is defined solely by the claims. Although an Interlocking Femoral Augments, similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present disclosure, the exemplary an Interlocking Femoral Augments is now described.
[0027] Referring now to the drawings, Figures. 1-5 illustrates an
interlock femoral augment system 100 according to present invention. It should be noted that Figure 1-5 are merely examples. A person skilled in the art will recognize many variations, alternatives, and modifications of the embodiments of the present disclosure. The augments may be any of various

types of geometrical shapes like circular, rectangular, trapezoidal and the like according to various embodiments of the present disclosure.
[0028] Referring now to the drawings, Fig. 1 illustrates Interlocking
Femoral Augments System 100 is disclosed. The system 100 comprises of a Posterior Femoral Augment 102 and a Distal Femoral Augment 104 in an interlocked position with each other.
[0029] Referring to Fig. 2(a) and 2(b), the posterior femoral augment 102
is disclosed that comprises of a top face 202, a bottom face 204, a cavity 206 that extends from the top face 202 to bottom face 204 to house a screw. The top face 202 comprises of a pocket 208 with a depth within a range of 0.5 - 1.5 mm on said posterior Femoral Augment, facilitating grip for cementing and augment interlocking. The bottom face 204 comprises of a protrusion 210 with a height ranging from 0.5 -1.5 mm facilitating interlocking with a femoral component 400 to prevent rotation and provide grip. The posterior femoral augment 102 may be selected from a plurality of augments having different thicknesses of 5 mm and 10 mm.
[0030] Referring to Fig. 3(a) and 3(b), the distal femoral augment 104 is
disclosed that comprises of a top face 302, a bottom face 304, a cavity 306 that extends from the top face 302 to bottom face 304 to house a screw. The top face 302 comprises of a pocket 308 with a depth within a range of 0.5 - 1.5 mm on distal Femoral Augment 104, facilitating grip for cementing and augment interlocking. The bottom face 302 comprises of a protrusion 310 with a height ranging from 0.5 -1.5 mm facilitating interlocking with a femoral component 400 to prevent rotation and provide grip. The distal femoral augment 104 may be selected from a plurality of augments having

different thicknesses of 5 mm, 10 mm, and 15 mm. The posterior 102 and distal 104 femoral augments are designed in such a way that they can be used interchangeably. For example, a 5mm thickness distal augment can be used with a 5mm or 10mm posterior augment and as the like combination.
[0031] Referring to Fig. 4(a) and 4(b), femoral prosthesis 400 is disclosed
comprising a posterior flange 402 and a distal flange 404. The femoral augment 102 and distal augment 104 are mounted on the posterior flange 402 and distal flange 404 respectively as shown in assembled state in fig.4(b).
[0032] Fig 5(a) and 5(b) discloses the pair of screws 502,504 that are
placed in the cavities 206 and 306 of posterior femoral augment 102 and distal femoral augment 104. Fig 5(a) discloses the screw 502 for 5mm thickness for both Posterior 102 and Distal Augments 104. Fig 5(b) discloses the screw 504 for 10mm and 15mm thickness for both Posterior 102 and Distal Augments 104. As illustrated in Fig 5(a) and 5(b), screws 502,504 includes a proximal end 506 and 506’ having a head portion 508 and 508’. The head 508,508’ further includes a threaded region 510,510’ that engages an internally threaded region of the cavities 206 and 306. Preferably, the head 508,508’ of screw 502,504 is of triangular geometry.
[0033] This augmentation system can be firmly secured to a prosthesis,
with no relative movement between the augmentation components and the prosthesis. The prosthesis further does not require post-casting machining processes to accept the augmentation system. The present invention has both technical as well as economic significance with respect to the conventional devices or the like.

[0034] While a particular embodiment of the invention has been
illustrated and described, modifications thereof will readily occur to those skilled in the art. It is understood that the various embodiment, details and constructions of the augment system and their features described above and illustrated in the attached Figures may be interchanged among the various embodiment while remaining within the scope of the invention.

We Claim:
1. An interlocking femoral augment system 100, comprising:
a Posterior femoral augment 102 having a top face 202 and a bottom face 204 wherein, the said Posterior Femoral Augment 102 has a predetermined thickness;
a Distal femoral augment 104 having a top face 302 and a bottom face 304 wherein, the said Distal Femoral Augment 104 has a predetermined thickness; and
a femoral prosthesis 400 having a posterior flange 402 and a distal flange 404,
wherein, the distal femoral augment 104 and the posterior femoral augment 102 are configured to interlock with each other and with the femoral prosthesis 400 with a primary and a secondary locking mechanism, thereby preventing rotation within augments as well as dislocation of augments with the femoral prosthesis 400.
2. The interlocking femoral augment system of claim 1, wherein the said distal
Femoral Augment 104 is mounted on a distal flange 404, and said predetermined thickness compensates for a bone defect volume and complements the shape of a corresponding interfacing surface of the femoral prosthesis 400.
3. The interlocking femoral augment system of claim 1, wherein the said
posterior Femoral Augment 102 is mounted on the posterior flange 402, and said predetermined thickness compensates for a bone defect volume and complements the shape of a corresponding interfacing surface of a femoral prosthesis 400.

4. The interlocking femoral augment system of claim 1 to 3, wherein the
predetermined thickness of said distal Femoral Augment 104 and said posterior Femoral Augment 102 is selected from a plurality of augments having different thicknesses of 5 mm, 10 mm and 15 mm.
5. The interlocking femoral augment system of claim 1 to 3, wherein the
predetermined thickness of said posterior Femoral Augment 102 is selected from a plurality of augments having different thicknesses of 5 mm and 10 mm.
6. The interlocking femoral augment system of claim 1, further comprising a
pocket 208,308 with a depth ranging from 0.5-1.5 mm on the top face of said posterior 102 and distal 104 Femoral Augment, facilitating grip for cementing and augment interlocking.
7. The interlocking femoral augment system of claim 1, further comprising a
protrusion 210,310 with a height ranging from 0.5 -1.5 mm on the bottom surface of said posterior 102 and distal 104 Femoral Augment, facilitating interlocking with a femoral component 400 to prevent rotation and provide grip.
8. The interlocking femoral augment system of claim 1, wherein the interlocking
of said distal 104 and posterior 102 Femoral Augment due to shape and geometry facilitate a compact fitment with a femoral component 400, thereby preventing rotation within augments.
9. The interlocking femoral augment system of any one of claims 1 to 7, wherein
the primary lock mechanism comprises of a pair of screws 502,504 for securing the interlocking of the distal femoral augment 104 and the posterior femoral augment 102 with the femoral prosthesis 400.
10. The interlocking femoral augment system of any one of claims 1 to 7,
wherein the secondary lock mechanism includes cementing for securing the
interlocking of the distal femoral augment 104 and the posterior femoral

augment 102 with each other and with the femoral prosthesis 400 thereby preventing dislocation of augments with the femoral prosthesis 400.