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:
ORTHOPEDIC 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:

 
FIELD OF INVENTION
[001] The present disclosure relates to a medical implant. More particularly, the present disclosure relates to an orthopedic implant.
BACKGROUND OF INVENTION
[002] Joints may need to be replaced when they become damaged due to an injury or disease. Joint replacement surgery is considered as a treatment when the damage in a joint is beyond repair or when the joint pain or dysfunction is not alleviated by less-invasive therapies. Joint replacement surgery, also known as arthroplasty, is a procedure in an orthopedic surgery in which a dysfunctional joint surface is replaced with an orthopedic prosthesis.
[003] For instance, a joint replacement surgery includes the replacement of a ball and a bearing of the joint. Fig.1 depicts a glenohumeral joint comprising the humerus and scapula representing a ball and a bearing joint. In a ball-and-bearing joint replacement surgery, the damaged components are removed and replaced with artificial parts (prosthesis) i.e., a ball and a bearing. The ball fits snugly into the bearing, enabling articulation of the limbs.
[004] Conventional implants include a structure where, a bearing sits on a tray. The tray on which the bearing sits, replaces the head of the bone. However, improper locking of the bearing to the tray results in loose-fitting of the bearing to the tray. Loose-fitting of the bearing to the tray leads to dislocation of the implant components. This can in turn cause uneven mechanical load distribution between joints leading to the rise of several complications and diseases such as osteolysis.
[005] Hence, there is a need of an implant that can overcome the problems associated with the conventional joint replacement implants.
SUMMARY OF INVENTION
[006] The present invention discloses an implant, including a proximal end and a distal end, a bearing and a tray. Further, the bearing includes two or more stoppers. The tray is operatively coupled to the bearing.
[007] The tray includes a base, two or more slots, one or more movable elements, two or more voids and two or more slits. The base is surrounded by a wall. The two or more slots extend from a top surface to a bottom surface of the base. One or more movable elements extend at least partially in each of the slots. Further, each of the voids are formed between an uncoupled side of the slots and a free edge of the movable elements. Two or more slits are formed in the uncoupled side of the slots. Wherein, the stoppers mate with the respective voids and slits.
BRIEF DESCRIPTION OF THE DRAWINGS
[008] The summary above, as well as the following detailed description of illustrative embodiments, is better understood when read in conjunction with the apportioned drawings. For the purpose of illustrating the present disclosure, exemplary constructions of the disclosure are shown in the drawings. However, the disclosure is not limited to specific methods and instrumentalities disclosed herein. Moreover, those in the art will understand that the drawings are not to scale.
[009] Fig. 1 depicts a perspective view of a glenohumeral joint, according to an embodiment of the present disclosure.
[0010] Fig. 2 depicts a perspective view of an orthopedic implant 100, according to an embodiment of the present disclosure.
[0011] Figs. 3a-3b depict respective perspective views of a bearing 300 of the orthopedic implant 100, according to an embodiment of the present disclosure.
[0012] Figs. 3c-3d depict respective perspective views of the first stopper 320 and the second stopper 325, according to an embodiment of the present disclosure.
[0013] Figs. 4a-4c depict respective perspective views of a tray 400 of the orthopedic implant 100, according to an embodiment of the present disclosure.
[0014] Fig. 4d depicts a magnified view of a slit 435a of the tray 400, according to an embodiment of the present disclosure.
[0015] Figs. 5a-5b depict a cross-sectional view of an assembled bearing 300 and tray 400 of the orthopedic implant 100, according to an embodiment of the present disclosure.
DETAILED DESCRIPTION OF ACCOMPANYING DRAWINGS
[0016] 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.
[0017] 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.
[0018] 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.
[0019] 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.
[0020] In accordance with the present disclosure, an orthopedic implant (hereinafter, an implant) is disclosed. The implant is used in various joint replacement surgeries such as, a reverse shoulder surgery. The damaged parts of a glenohumeral joint are replaced with the implant.
[0021] The tray and the bearing of the implant are locked via a secure locking mechanism defined between the two. The secure locking mechanism keeps the tray and the bearing of the implant firmly in place. This also reduces the risk of dislocation of the tray and the bearing, enhancing the implant’s function and longevity and helps to distribute mechanical load evenly thus, minimizing stress concentration between the tray and the bearing. Further, the design of the implant simplifies the surgical process by cutting down surgery time and minimizing errors.
[0022] Though the locking mechanism of the present disclosure is explained with respect to a shoulder implant, it can be extended to different parts of the human body, such as a hip implant, which are within the scope of the teachings of the present disclosure.
[0023] Now referring to the figures, Fig. 2 depicts a perspective view of an implant 100. The implant 100 replaces the injured or damaged head of the humerus bone of the glenohumeral joint. The implant 100 includes a proximal end 120 and a distal end 140. The implant 100 includes a bearing 300 disposed at the distal end 140 and a tray 400 disposed at the proximal end 120 of the implant 100. The tray 400 is operatively coupled to the bearing 300, which has been explained later. Details of the bearing 300 have been explained in the context of Figs 3a-3d while details of the tray 400 have been explained in the context of Figs. 4a-4d.
[0024] The bearing 300 may be made of any biocompatible poly metal material or metal. The metal that may be used in making the bearing 300 may include, without limitation, Titanium, cobalt chromium, SS 316, HNSS, etc., or a combination thereof. The poly material includes without limitation, ultra-high molecular weight polyethylene (UHMWPE), polymethyl methacrylate (PMMA), highly cross-linked polyethylene (HXLPE) including Vitamin E, polyether ether ketone (PEEK). In an exemplary embodiment, the bearing 300 is made of ultra-high molecular weight polyethylene (UHMWPE). Alternatively, the bearing 300 can be made of any poly material without any metal. The dimensions of the bearing 300 may vary according to or based upon the anatomy of the patient and/or of the patient population in consideration.
[0025] The bearing 300 includes a top surface 305 and a bottom surface 310. The bearing 300 is a tubular structure, including a slant. The top surface 305 is depicted in Fig. 3a. The top surface 305 of the bearing 300 is slanted. That is, the width of the bearing 300 reduces from, a first end 305a to a diametrically opposite second end 305b. In the depicted embodiment, L1 and L2 define the width of two diametrically opposite ends, the first end 305a and the second end 305b. As shown, L2 is less than L1. This slant conforms to the underlying human anatomy where the implant 100 is to be secured.
[0026] The top surface 305 of the bearing 300 may include a curvature. In an embodiment, the top surface 305 includes a concave curvature. In another embodiment, the top surface 305 includes a convex curvature. The curvature of the top surface 305 of the bearing 300 is configured to receive at least a portion of the glenoid component.
[0027] The bottom surface 310 is depicted in Fig. 3b. The bottom surface 310 of the bearing 300 is configured to sit over the surface of the tray 400 of the implant 100.
[0028] The bottom surface 310 of the bearing 300 includes a central disc 315 (hereinafter, a disc). The disc 315 is depicted in Figs. 3a-3b. The disc 315 extends away from the bottom surface 310 defining a specific height. It is to be noted that the height of the disc 315 may vary, and is dependent on a patient’s anatomy. In an embodiment, the disc 315 has a circular cross-section. Alternately, the disc 315 includes one of a circular, oval, sphere, or ellipse shape. The disc 315 is configured to sit over a base 415 of the tray 400 for effective locking of the tray 400 and the bearing 300, as described below. Further, the disc 315 provides stability to the implant 100.
[0029] The bearing 300 includes two or more stoppers. More specifically, the disc 315 of the bearing 300 includes two or more stoppers. In an embodiment, the disc 315 includes two stoppers namely, a first stopper 320 and a second stopper 325. Figs. 3c-3d depict the first stopper 320 and the second stopper 325 respectively. In an embodiment, the first stopper 320 and the second stopper 325 are placed at diametrically opposite ends of the disc 315. Alternately, the first stopper 320 and the second stopper 325 may be placed at a predefined angle with respect to the center. While the depicted embodiment illustrates two stoppers, more than two stoppers can be provided as per the teachings of the present invention. In such case, two consecutive stoppers may be arranged angularly with respect to each other. The stoppers are configured to mate with the respective voids in the slots of the tray 400 for effective locking of the tray 400 and the bearing 300, as described below.
[0030] As shown in Fig. 3c, the first stopper 320 includes a vertical slab 320a and a horizontal slab 320b. The vertical slab 320a extends away from the disc 315, defining a specific height. It is to be noted that, the height of the vertical slab 320a may vary, and is dependent on a patient’s anatomy. The top surface of the vertical slab 320a is coupled to the horizontal slab 320b that extends away from the vertical slab 320a defining a specific width. Further, the width of the horizontal slab 320b may vary, and is dependent on a patient’s anatomy. The vertical slab 320a and the horizontal slab 320b thus form a substantially L-shaped first stopper 320. The horizontal slab 320b extends away from the vertical slab 320a such that, a hollow a space is created between the bottom surface of the horizontal slab 320b and the disc 315. The horizontal slab 320b is configured to fit into a slit 425a of the tray 400 for effective locking of the tray 400 and the bearing 300, as described below.
[0031] As shown in Fig. 3d, the second stopper 325 includes a vertical slab 325a and a horizontal slab 325b. The vertical slab 325a extends away from the disc 315, defining a specific height. It is to be noted that, the height of the vertical slab 325a may vary, and is dependent on a patient’s anatomy. The top surface of the vertical slab 325a is coupled to, the horizontal slab 325b that extends away from the vertical slab 325a defining a specific width. Further, the width of the horizontal slab 325b may vary, and is dependent on a patient’s anatomy. The vertical slab 325a and the horizontal slab 325b thus form a substantially L-shaped second stopper 325. The horizontal slab 325b extends away from the vertical slab 325a such that, a hollow a space is created between the bottom surface of the horizontal slab 325b and the disc 315. The horizontal slab 325b is configured to fit into a slit 435a of the tray 400 for effective locking of the tray 400 and the bearing 300, as described below.
[0032] Figs. 4a-4b depict various perspective views of the tray 400. The tray 400 may be made of any biocompatible poly material or metal. The metal that may be used in making the tray 400 includes, without limitation, titanium, cobalt chromium, SS 316, HNSS, or a combination thereof. The poly material includes without limitation, titanium, cobalt chromium, and stainless steel (SS316). The poly material includes without limitation, ultra-high molecular weight polyethylene (UHMWPE), polymethyl methacrylate (PMMA), highly cross-linked polyethylene (HXLPE) including Vitamin E, PEEK etc. In an exemplary embodiment, the tray 400 is made of titanium. The dimensions of the tray 400 may vary according to or based upon the anatomy of the patient and/or of the patient population in consideration.
[0033] The tray 400 includes a top surface 410 and a bottom surface 405. The bottom surface 405 of the tray 400 towards the proximal end 120, may include an extension 440. The extension 440 is used to fix the implant 100 to the humerus bone of the glenohumeral joint. The extension 440 may be cylindrical, sphere, oval, circular, conical, etc. in shape.
[0034] The top surface 410 of the tray 400 is configured to receive the bottom surface 310 of the bearing 300. The top surface 410 of the tray 400 is shown in Fig. 4a-4b. The top surface 410 of the tray 400 includes a central base 415 (hereinafter a base). The base 415 is surrounded by a wall extending from the edge of the base 415. In an embodiment, the base 415 is circular. The base 415 of the tray 400 is configured to interface with the disc 315 of the bearing 300 for effective locking of the tray 400 and the bearing 300, as described below.
[0035] As shown in Fig. 4a, the base 415 of the tray 400 includes two or more slots, that extend from a top surface to a bottom surface of the base 415. Each slot is provided with a predefined width. It is to be noted that, the width of each of the slots reciprocates the dimensions of the corresponding horizontal slabs 320b, 325b of the bearing 300 to be seated within. In an embodiment, the slots are arc-shaped, subtending a specific angle at the center of the base 415. Further, the angle subtended by the slots may vary between different embodiments of the implant 100, depending on the patient's anatomy. According to an embodiment, each slot extends from the top surface 410 to the bottom surface 405 of the tray 400.
[0036] According to the depicted embodiment, there are two slots namely, a first slot 420 and a second slot 430. The first slot 420 and the second slot 430 may have different shapes such as, semi-circular, arc or rectangle. The first slot 420 and the second slot 430 are placed at diametrically opposite portions of the base 415. It is to be noted that the number of slots of the tray 400 correspond to the number of stoppers of the bearing 300. Hence, in case more than two stoppers are provided, the number of slots will vary accordingly. Also, the disposition of the slots of the tray 400 corresponds to the disposition of the stoppers of the bearing 300.
[0037] As shown in Fig. 4b, the slots 420/430 of the tray 400 includes one or more movable elements, extending at least partially in each of the slots 420/430. In an embodiment, the movable elements are arc-shaped, subtending a specific angle at the center of the base 415. The first slot 420 includes a movable element 420c while the second slot 430 includes a movable element 430c. Figs. 4a-4c depicts the movable elements 420c/430c. Each of the movable elements 420c/430c is attached to the base 415 at one side and free or unattached to the base 415 at the remaining three sides. The side of the base 415 opposite to the attached side of the movable elements 420c,430c is referred as an uncoupled side. Further, the first slot 420 and the second slot 430 are configured to confine the movable elements 420c,430c within the respective slots 420,430. This gives the movable elements 420c, 430c a movable character in a vertical direction along the inner walls of each of the slots 420, 430. Further, the each of the movable elements 420c/430c are configured to restrict the reverse rotation of the bearing 300, owing to the vertical movement of the movable elements 420c, 430c within the slots 420/430 for effective locking of the tray 400 and the bearing 300, as described below.
[0038] According to an embodiment, the movable elements 420c/430c may extend along the entire or partial length of the slots 420, 430. In the latter case wherein the movable elements 420c/430c are provided till partial length of the slots 420, 430, a void 425 or 435 is created. Specifically, the voids 425/435 are formed between the uncoupled side of the corresponding slots 420/430 and a free edge of the corresponding movable elements 420c, 430c.
[0039] Further, the uncoupled side of the slots includes two or more slits. Fig. 4d depicts a magnified view of the slit. The uncoupled side of the first slot 420 includes a slit 425a while the uncoupled side of the second slot 430 includes a slit 435a. In an embodiment, the slits 425a, 435a have a rectangular cross-section. Alternately, the cross-section of the slits 425a, 435a may vary corresponding to the cross-section of the stoppers 320, 325.
[0040] The movable elements 420c, 430c may have a predefined width. In an embodiment, width of the movable elements 420c, 430c corresponds to the width of the slots 420, 430. In an embodiment, the movable elements 420c, 430c are arc-shaped. The shape of the movable elements 420c/430c is dependent upon the shape of the slots 420/430.
[0041] The movable elements 420c/430c, the slits 425a, 435a and the slots 420, 430 of the tray 400, the disc 315, and the stoppers 320, 325 of the bearing 300 may be laser cut, or carved using any optimal machining process in the respective components. Alternately, these may be separate components and thereafter welded, etc.
[0042] The disc 315 and the stoppers 320, 325 of the bearing 300 along with the slots 420, 430, movable elements 420c, 430c and the slits 425a, 435a of the tray 400 define the locking mechanism of the implant 100. To assemble the implant 100, the bearing 300 of the implant 100 is placed over the tray 400 of the implant 100. The disc 315 at the bottom surface 310 of the bearing 300 is aligned with the base 415 of the tray 400.
[0043] Next, the first stopper 320 of the bearing 300 is inserted in the void 425 while the second stopper 325 of the bearing 300 is inserted in the void 435. The horizontal slab 320b of the first stopper 320 is aligned and inserted in the slit 425a. Similarly, the horizontal slab 325b of the second stopper 325 is aligned and inserted in the slit 435a. Once the horizontal slabs 320b, 325b of the stoppers 320, 325 are inserted in the respective slits 425a, 435a, due to a push exerted by the horizontal slabs 320b, 325b of the stoppers 320, 325 on the unattached end of the respective movable elements 420c, 430c, each of the movable elements 420c/430c is pushed downwards along the first slot 420 and the second slot 430 respectively.
[0044] For assembly, the bearing 300 is rotated over the tray 400 in a desired direction. In an embodiment, the bearing 300 is rotated in the anticlockwise direction. However, in another embodiment, the bearing 300 is rotated in the clockwise direction. Further, the horizontal slab 320b of the first stopper 320 slides through the movable element 420c of the first slot 420 and the horizontal slab 325b of the second stopper 325 slides through the movable element 430c of the second slot 430.
[0045] Thereafter, the first stopper 320 passes into the void 425 of the first slot 420 and the second stopper 325 passes into the void 435 of the second slot 430. As shown in Fig. 5a, the horizontal slab 320b fits into the slit 425a of the void 425. Similarly, the horizontal slab 325b fits into the slit 435a of the void 435. Thereafter, the movable element 420c and the movable element 430c revert to their original position in the first slot 420 and the second slot 430 respectively, locking the bearing 300 with the tray 400 of the implant 100 as shown in Fig. 5b. Given the movable elements 420c, 430c is made of a compressible material, the stoppers 320, 325 remains firmly seated in the respective slits 425a, 435a, thereby, providing a rigid and immovable coupling of the tray 400 and the bearing 300.
[0046] The implant 100 replaces the head of the humerus bone. A diseased portion of the humerus bone of the glenohumeral joint is removed. The head of the humerus bone, after removing the diseased part is reamed. The extension 440 of the tray 400 is placed in the reamed portion of the humeral bone. The extension 440 may be cemented with the bone to ensure a secure fit. Thus, replacing the head of the humerus bone of the glenohumeral joint with the implant 100.
[0047] It is to be noted that the aforesaid description details various stoppers/projections, slots/grooves etc. which function in pair. Thus, the disposition and shape of two corresponding mating component is complementary. Any alteration of one component is to be replicated to the corresponding mating component.
[0048] 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 proximal end (120) and a distal end (140);
b. a bearing (300) including two or more stoppers (320, 325); and
c. a tray (400) operatively coupled to the bearing (300), the tray (400) including:
i. a base (415),
ii. a wall surrounding the base (415);
iii. two or more slots (420, 430) that extend from a top surface to a bottom surface of the base (415);
iv. one or more movable elements (420c, 430c) extending at least partially in each of the slots (420, 430);
v. two or more voids (425, 435), each void formed between an uncoupled side of the slots (420, 430) and a free edge of the movable elements (420c), 430c); and
vi. two or more slits (425a, 435a) formed in the uncoupled side of the slots (420, 430);
wherein the stoppers (320, 325) mate with the respective voids (425, 435) and slits (425a, 435a).
2. The implant (100) as claimed in claim 1 wherein, at least one of the, bearing (300) and the tray (400) are made from one of a biocompatible metal or poly material.
3. The implant (100) as claimed in claim 1 wherein, a top surface (305) of the bearing (300) includes a curvature.
4. The implant (100) as claimed in claim 1 wherein, the bottom surface (405) of the tray (400) includes an extension (440).
5. The implant (100) as claimed in claim 1 wherein, the bearing (300) is a tubular structure including a slant.
6. The implant (100) as claimed in claim 1 wherein, the bearing (300) includes a central disc (315).
7. The implant (100) as claimed in claim 4 wherein, the disc (315) includes one of a circular, oval, sphere, or ellipse shape.
8. The implant (100) as claimed in claim 1 wherein, the plurality of stoppers (320, 325) and/or the slots (420, 430) are placed diametrically opposite to each other.
9. The implant (100) as claimed in claim 1 wherein, each of the plurality of stoppers includes a vertical slab (320a, 325a) and a horizontal slab (320b, 325b) forming a substantially L-shape.
10. The implant (100) as claimed in claim 1 wherein, the slots (420, 430) are arc shaped.
11. The implant (100) as claimed in claim 1 wherein, the movable elements (420c, 430c) are arc shaped.