Description:FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(Section 10 and Rule 13)

1. TITLE OF THE INVENTION:
HIP IMPLANT

2. APPLICANT:
Meril Corporation (I) Private Limited, an Indian company of the address Survey No. 135/139, Muktanand Marg, Bilakhia House, Pardi, Vapi, Valsad-396191 Gujarat, India.

The following specification particularly describes the invention and the manner in which it is to be performed:

FILED OF THE INVENTION
[001] The present disclosure relates to a medical device. More particularly, the present disclosure relates to a hip implant.
BACKGROUND OF THE INVENTION
[002] A traditional hip replacement surgery includes an implant with two sub-assemblies. The first sub-assembly includes a cemented cup and a modular liner which forms the acetabulum part of the anatomy. The second sub-assembly includes a head and a stem which forms a femoral part of the anatomy. The two assemblies are coupled together to form an artificial hip joint.
[003] In reverse hip replacement surgery, an implant having a first sub assembly of a cemented cup and a modular head is used. The second sub-assembly includes a modular liner and a femoral stem.
[004] Reverse hip replacement surgery is preferred over traditional hip surgery when traditional hip replacement surgery fails to provide adequate stability and function. For example, in case of severe arthritis, severe femoral bone loss/fractures, multiple prior replacement surgeries, bone tumors, and/or congenital deformities, reverse hip replacement may be preferred course of treatment.
[005] However, conventional implants used for reverse hip replacement surgery fails to provide the range of motion that is achieved in traditional hip replacement surgery.
[006] Hence, there arises a need for an implant that overcomes the drawback associated with the conventional implants.
SUMMARY OF THE INVENTION
[007] Particular embodiments of the present disclosure are described herein below with reference to the accompanying drawings; however, it is to be understood that the disclosed embodiments are mere examples of the disclosure, which may be embodied in various forms. Well-known functions or constructions are not described in detail to avoid obscuring the present disclosure in unnecessary detail. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present disclosure in virtually any appropriately detailed structure.
[008] The present disclosure relates to an implant including a cup, a first elongate member, a head, a liner, a second elongate member, and a stem. The cup is disposed at a first end. The cup has a face and a tail extending from the face towards a second end. The head is coupled to the cup. The head has a cavity. The liner has a body and a leg extending from the body towards the second end. The body is provided with a cavity. The head is at least partially disposed within the cavity of the liner. The stem is coupled to the liner. The stem has a neck provided with a cavity. The tail of the cup is coupled to the cavity of the head via the first elongate member. The first elongate member has an opening towards the first end. The opening of the first elongate member is configured to at least partially receive the tail of the cup. The cavity of the head is configured to at least partially receive the first elongate member. The leg of the liner is coupled to the cavity of the stem via the second elongate member. The second elongate member has an opening towards the first end. The opening of the second elongate member is configured to at least partially receive the leg of the liner. The cavity of the stem is configured to at least partially receive the second elongate member.
BRIEF DESCRIPTION OF DRAWINGS
[009] The summary above and the detailed description of descriptive embodiments, is better understood when read in conjunction with the apportioned drawings. For illustration of the present disclosure, exemplary constructions of the disclosure are shown in the drawings. However, the disclosure is not limited to specific methods and instrumentality disclosed herein. Moreover, those in the art will understand that the drawings are not to scale.
[0010] Fig. 1 depicts an implant 100, according to an embodiment of the present invention.
[0011] Fig. 1a depicts a cross-sectional view of the implant 100, according to an embodiment of the present invention.
[0012] Fig. 2 depicts an exploded view of the implant 100, according to an embodiment of the present invention.
[0013] Fig. 3 depicts a cup 110 of the implant 100, according to an embodiment of the present invention.
[0014] Fig. 4 depicts a first elongate member 120 of the implant 100, according to an embodiment of the present invention.
[0015] Fig. 5 depicts a head 130 of the implant 100, according to an embodiment of the present invention.
[0016] Fig. 6 depicts a liner 140 of the implant 100, according to an embodiment of the present invention.
[0017] Fig. 7 depicts a second elongate member 150 of the implant 100, according to an embodiment of the present invention.
[0018] Fig. 8 depicts a stem 160 of the implant 100, according to an embodiment of the present invention.
[0019] Figs. 9a-c depict a range of motion associated with the implant 100, according to an embodiment of the present invention.
DETAILED DESCRIPTION OF DRAWINGS
[0020] Prior to describing the disclosure in detail, definitions of certain words or phrases used throughout this patent document will be defined: the terms "include" and "comprise", as well as derivatives thereof, mean inclusion without limitation; the term "or" is inclusive, meaning and/or; the phrases "coupled with" and "associated therewith", as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have a property of, or the like. Definitions of certain words and phrases are provided throughout this patent document, and those of ordinary skill in the art will understand that such definitions apply in many, if not most, instances to prior as well as future uses of such defined words and phrases.
[0021] Reference throughout this specification to “one embodiment,” “an embodiment,” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases “in one embodiment,” “in an embodiment,” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment, but mean “one or more but not all embodiments” unless expressly specified otherwise. The terms “including,” “comprising,” “having,” and variations thereof mean “including but not limited to” unless expressly specified otherwise. An enumerated listing of items does not imply that any or all of the items are mutually exclusive and/or mutually inclusive, unless expressly specified otherwise. The terms “a,” “an,” and “the” also refer to “one or more” unless expressly specified otherwise.
[0022] Although the operations of exemplary embodiments of the disclosed method may be described in a particular, sequential order for convenient presentation, it should be understood that the disclosed embodiments can encompass an order of operations other than the particular, sequential order disclosed. For example, operations described sequentially may in some cases be rearranged or performed concurrently. Further, descriptions and disclosures provided in association with one particular embodiment are not limited to that embodiment, and may be applied to any embodiment disclosed herein. Moreover, for the sake of simplicity, the attached figures may not show the various ways in which the disclosed system, method, and apparatus can be used in combination with other systems, methods, and apparatuses.
[0023] Furthermore, the described features, advantages, and characteristics of the embodiments may be combined in any suitable manner. One skilled in the relevant art will recognize that the embodiments may be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments. These features and advantages of the embodiments will become more fully apparent from the following description and apportioned claims, or may be learned by the practice of embodiments as set forth hereinafter.
[0024] The present disclosure relates to a hip implant (or implant). The implant may be used in reverse hip replacement surgeries to at least partially replace diseased hip joints.
[0025] Although the present disclosure is described with the example of a hip implant, the teachings of the present disclosure is applicable to any stem-like prosthesis and the same is within the scope of the teachings of the present disclosure.
[0026] The implant of the present disclosure provides a range of motion similar to that of the implants used in traditional hip replacement surgeries. The implant includes a cup, a head, a liner, and a stem. The implant further includes a first elongate member and a second elongate member. The first elongate member helps to couple the cup with the head and the second elongate member helps to couple the liner with the stem such that the range of motion of the implant is improved.
[0027] Now referring to the figures, Fig. 1 depicts an implant 100 and Fig. 1a depicts a cross sectional view of the implant 100, according to an embodiment. The implant 100 includes a cup 110, a head 130, a liner 140, a stem 160. The implant 100 extends between a first end 100a and a second end 100b such that the cup 110 is disposed at the first end 100a and the stem 160 is disposed at the second end 100b. An exploded view of the implant 100 is depicted in Fig. 2. As shown in Fig. 2, the implant 100 further includes a first elongate member 120 and a second elongate member 150.
[0028] The cup 110 of the implant 100 is depicted in Fig. 3. The cup 110 is implanted within, for example, the pelvic bone such that it forms the acetabulum portion of a diseased hip joint. The cup 110 is made of a material including, but not limited to, ultra-high-molecular-weight polyethylene (UHMWPE), polymethyl methacrylate (PMMA), Highly cross-linked polyethylene (HXLPE) including vitamin E, etc. In an exemplary embodiment, the cup 110 is made of UHMWPE.
[0029] The cup 110 has a face 111 and a tail 113. The tail 113 may be fixedly coupled to the face 111. Alternatively, the face 111 and the tail 113 form an integral unit. In an exemplary embodiment, the face 111 and the tail 113 is an integral unit.
[0030] The face 111 may be solid or hollow. In an exemplary embodiment, as shown in Fig. 3, the face 111 is solid and hemi-spherical. The face 111 has dimensions corresponding to the acetabulum where it is implanted. An outer surface of the face 111 may be provided with a plurality of surface features including, but not limited to, holes, cavities, grooves, projections, etc. The surface features of the face 111 helps in better cementing of the cup 110 to the acetabulum when implanted.
[0031] The tail 113 extends from a center of the face 111 towards the second end 100b. The tail 113 may define an angle with the face 111. In an exemplary embodiment, the tail 113 is perpendicular to the face 111. The tail 113 may have a length depending on the bone anatomy of the patient.
[0032] In an exemplary embodiment, as shown in Fig. 3, the tail 113 has a tapering diameter. The tapering may decrease from the first end 100a towards the second end 100b. In an exemplary embodiment, the tail 113 has a 12/14 taper.
[0033] Fig. 4 depicts the first elongate member 120 of the implant 100. The first elongate member 120 may be made of a material including, but not limited to, titanium, cobalt chromium (co-cr), stainless steel (SS), etc. or any other medical grade biocompatible material. In an exemplary embodiment, the first elongate member 120 is made of titanium.
[0034] The first elongate member 120 has a pre-defined length depending on the bone anatomy of the patient. In an exemplary embodiment, the length of the first elongate member 120 is same as the length of the tail 113 of the cup 110.
[0035] The first elongate member 120 includes an opening 121 towards the first end 100a. The opening 121 is configured to receive at least a portion of the tail 113 of the cup 110 such that the cup 110 is coupled to the first elongate member 120 via the tail 113. The first elongate member 120 may have an internal diameter corresponding to the diameter of the tail 113 of the cup 110. In an exemplary embodiment, the internal diameter of the first elongate member 120 corresponds to the 12/14 taper of the tail 113 of the cup 110. The tail 113 of the cup 110 may be coupled to the opening 121 of the first elongate member 120 by press-fit, taper-fit, friction-fit, etc. In an exemplary embodiment, the tail 113 of the cup 110 is coupled to the opening 121 of the first elongate member 120 via 12/14 taper-fit.
[0036] In an exemplary embodiment, as shown in Fig. 3, the first elongate member 120 has a tapering external diameter. The tapering may decrease from the first end 100a towards the second end 100b. In an exemplary embodiment, the first elongate member 120 has a 12/14 taper.
[0037] The head 130 is depicted in Fig. 5 of the implant 100. The head 130 is made of a medical grade biocompatible material including, but not limited to, co-cr, SS, titanium, ceramic, etc. In an exemplary embodiment, the head 130 is made of co-cr.
[0038] In an exemplary embodiment, as shown in Fig. 5, the head 130 is at least partially spherical. The head 130, towards the first end 100a is flat.
[0039] The head 130 is provided with a cavity 131 towards the first end 100a. The cavity 131 may have a depth depending on the bone anatomy of the patient. In an exemplary embodiment, the depth of the cavity 131 is same as the length of the first elongate member 120.
[0040] The cavity 131 is configured to at least partially receive the first elongate member 120. The cavity 131 may have an internal diameter corresponding to the external diameter of the first elongate member 120. In an exemplary embodiment, the internal diameter of the cavity 131 corresponds to the 12/14 taper of the first elongate member 120. The first elongate member 120 may be coupled to the cavity 131 of the head 130 by press-fit, taper-fit, friction-fit, etc. In an exemplary embodiment, the first elongate member 120 is coupled to the cavity 131 of the head 130 via 12/14 taper-fit.
[0041] The liner 140 is depicted in Fig. 6 of the implant 100. The liner 140 may have a pre-defined shape including, but not limited to, cylindrical, torus, cone, prism, etc. In an exemplary embodiment, as shown in Fig. 6, the liner 140 is cylindrical. The liner 140 may be made of a material including, but not limited to, UHMWPE, PMMA, HXLPE including vitamin E, etc. In an exemplary embodiment, the liner 140 is made of UHMWPE. The liner 140 includes a body 141 and a leg 143. The body 141 is disposed towards the first end 100a and the leg 143 is disposed towards the second end 100b. The leg 143 may be fixedly coupled to the body 141. Alternatively, the body 141 and the leg 143 form an integral unit. In an exemplary embodiment, the body 141 and the leg 143 is an integral unit.
[0042] The body 141 is provided with a cavity 141a towards the first end 100a. The cavity 141a may have dimensions corresponding to that of the head 130. The cavity 141a is configured to at least partially receive the head 130, similar to a ball and socket joint.
[0043] The leg 143 extends from a center of the body 141 towards the second end 100b. The leg 143 may define an angle with the body 141. In an exemplary embodiment, the leg 143 is perpendicular to the body 141. The leg 143 may have a length depending on the bone anatomy of the patient.
[0044] In an exemplary embodiment, as shown in Fig. 6, the leg 143 has a tapering diameter. The tapering may decrease from the first end 100a towards the second end 100b. In an exemplary embodiment, the leg 143 has a 12/14 taper.
[0045] Fig. 7 depicts the second elongate member 150 of the implant 100. The second elongate member 150 may be made of a material including, but not limited to, titanium, co-cr, SS, etc. or any other medical grade biocompatible material. In an exemplary embodiment, the second elongate member 150 is made of titanium. The second elongate member 150 has a pre-defined length depending on the bone anatomy of the patient. In an exemplary embodiment, the length of the second elongate member 150 is same as the length of the leg 143 of the liner 140.
[0046] The second elongate member 150 includes an opening 151 towards the first end 100a. The opening 151 is configured to receive at least a portion of the leg 143 of the liner 140 such that the liner 140 is coupled to the second elongate member 150 via the leg 143. The second elongate member 150 may have an internal diameter corresponding to the diameter of the leg 143 of the liner 140. In an exemplary embodiment, the internal diameter of the second elongate member 150 corresponds to the 12/14 taper of the leg 143 of the liner 140. The leg 143 of the liner 140 may be coupled to the opening 151 of the second elongate member 150 by press-fit, taper-fit, friction-fit, etc. In an exemplary embodiment, the leg 143 of the liner 140 is coupled to the opening 151 of the second elongate member 150 via 12/14 taper fit.
[0047] In an exemplary embodiment, as shown in Fig. 7, the second elongate member 150 has a tapering external diameter. The tapering may decrease from the first end 100a towards the second end 100b. In an exemplary embodiment, the second elongate member 150 has a 12/14 taper.
[0048] Fig. 8 depicts the stem 160 of the implant 100. The stem 160 may be made of a pre-defined material including, but not limited to, titanium, co-cr, SS etc. or any other medical grade biocompatible material. In an exemplary embodiment, the stem 160 is made of titanium. The stem 160 is implanted at least partially within, for example, the femoral bone.
[0049] The stem 160 may have a shape and size corresponding to a femoral canal in which the stem 160 is implanted. The stem 160 may be provided with a neck 161 defining an angle with an axial axis of the stem 160. The angle may depend on the bone anatomy where the implant 100 is implanted. The neck 161 is disposed towards the first end 100a.
[0050] The neck 161 is provided with a cavity 161a towards the first end 100a. The cavity 161a may have a depth depending on the bone anatomy of the patient. In an exemplary embodiment, the depth of the cavity 161a is same as the length of the second elongate member 150.
[0051] The cavity 161a is configured to at least partially receive the second elongate member 150. The cavity 161a may have an internal diameter corresponding to the external diameter of the second elongate member 150. In an exemplary embodiment, the internal diameter of the cavity 161a corresponds to the 12/14 taper of the first elongate member 120. The second elongate member 150 may be coupled to the cavity 161a of the stem 160 by press-fit, taper-fit, friction-fit, etc. In an exemplary embodiment, the second elongate member 150 is coupled to the cavity 161a of the stem 160 via 12/14 taper-fit.
[0052] Now the implant 100 of the present disclosure will be explained with the help of following examples:
[0053] Example 1 (Prior art): A conventional total hip implant (used for traditional hip replacement surgery) was obtained and was characterized on the following physical parameters:
Type of motion Conventional implant
Flexion 77°
Extension 77°
Total flexion/Extension 154°
Abduction 52.5°
Adduction 52.5°
Total Abduction/Adduction 105°
Internal Rotation 77.5°
External Rotation 77.5°
Total Internal/External Rotation 155°

[0054] The conventional implant provided inferior range of motion which may not be apt for patients with severe symptoms.
[0055] Example 2 (Present disclosure): The implant 100 was assembled by coupling the cup 110 with the head 130 using the first elongate member 120. Thereafter, the liner 140 was coupled to the stem 160 using the second elongate member 150. And, lastly, the head 130 was coupled to the liner 140. The implant 100 was characterized on the following physical parameters:
Type of motion Implant 100
Flexion (Fig. 9a) 80°
Extension (Fig. 9a) 80°
Total flexion/Extension (Fig. 9a) 160°
Abduction (Fig. 9b) 51.2°
Adduction (Fig. 9b) 53.2°
Total Abduction/Adduction (Fig. 9b) 104.2°
Internal Rotation (Fig. 9c) 80°
External Rotation (Fig. 9c) 80°
Total Internal/External Rotation (Fig. 9c) 160°

[0056] The implant 100 of the present disclosure demonstrated improved range of motion, thereby, providing apt replacement even to patients with severe symptoms.
[0057] The scope of the invention is only limited by the appended patent claims. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and/or configurations will depend upon the specific application or applications for which the teachings of the present invention is/are used. , Claims:WE CLAIM
1. An implant (100) comprising:
a. a cup (110) disposed at a first end (100a), the cup (110) having a face (111) and a tail (113) extending from the face (111) towards a second end (100b);
b. a head (130) coupled to the cup (110), the head (130) having a cavity (131);
c. a liner (140) having a body (141) and a leg (143) extending from the body (141) towards the second end (100b), the body (141) is provided with a cavity (141a), the head (130) is at least partially disposed within the cavity (141a) of the liner (140);
d. a stem (160) coupled to the liner (140), the stem (160) having a neck (161) provided with a cavity (161a);
e. a first elongate member (120) coupling the cup (110) to the head (130); and
f. a second elongate member (150) coupling the liner (140) to the stem (160);
wherein, the tail (113) of the cup (110) is coupled to the cavity (131) of the head (130) via the first elongate member (120), the first elongate member (120) having an opening (121) towards the first end (100a), the opening (121) of the first elongate member (120) is configured to at least partially receive the tail (113) of the cup (110), the cavity (131) of the head (130) is configured to at least partially receive the first elongate member (120), and
wherein, the leg (143) of the liner (140) is coupled to the cavity (161a) of the stem (160) via the second elongate member (150), the second elongate member (150) having an opening (151) towards the first end (100a), the opening (151) of the second elongate member (150) is configured to at least partially receive the leg (143) of the liner (140), the cavity (161a) of the stem (160) is configured to at least partially receive the second elongate member (150).
2. The implant (100) as claimed in claim 1, wherein the tail (113) of the cup (110) has a tapering diameter.
3. The implant (100) as claimed in claim 1, wherein the cavity (131) of the head (130) has a tapering internal diameter.
4. The implant (100) as claimed in claim 1, wherein the first elongate member (120) has a tapering internal diameter and a tapering external diameter.
5. The implant (100) as claimed in claim 1, wherein an internal and external diameter of the first elongate member (120) includes 12/14 taper.
6. The implant (100) as claimed in claim 1, wherein the leg (143) of the liner (140) has a tapering diameter.
7. The implant (100) as claimed in claim 1, wherein the cavity (161a) of the stem (160) has a tapering internal diameter.
8. The implant (100) as claimed in claim 1, wherein the second elongate member (150) has a tapering internal diameter and a tapering external diameter.
9. The implant (100) as claimed in claim 1, wherein an internal and external diameter of the second elongate member (150) includes 12/14 taper.
10. The implant (100) as claimed in claim 1, wherein the coupling between the head (130) and the liner (140) is similar to that of a ball and socket joint.