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:
SHOULDER 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 an implant. More particularly, the present disclosure relates to a shoulder implant.
BACKGROUND OF THE INVENTION
[002] Shoulder replacement surgery is a procedure to replace the native damaged components of a shoulder joint like glenoid, humeral head and/or humeral stem with artificial implants. Usually, the surgical procedure includes replacing the damaged humeral head of the humerus bone. The implant includes two portions, viz., one head portion for replacing the natural humeral head and a stem disposed inside the humerus bone.
[003] After removing the humeral head, a cavity is reamed inside the humerus bone to insert a stem portion. The cavity is reamed such that it forms a canal inside the humerus, and its position determines the alignment of the implant with glenoid in the shoulder. Position of the reamed canal varies based on the natural structure of the bones of the patient, and the reamed canal may not be always in the centre of the humerus as desired. This affect the alignment of the implant placement as the coupling between the head and stem portions are affected. The head portion of the implant is coupled to the stem portion using a coupling mechanism.
[004] Conventional coupling mechanism such as press-fit, sliding mechanism, adhesive bonding, anchoring etc. provide connection between the head portion and the stem portion of the prosthetic disregarding proper alignment.
[005] Therefore, there arises a need for an improved coupling mechanism overcoming the problems associated with the conventional implants.
SUMMARY OF THE INVENTION
[006] 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.
[007] The present disclosure relates to a shoulder implant including a head and stem. The head has a base. At least a first portion of the base is provided with a plurality of holes. The stem has a proximal portion. The proximal portion is provided with a flat surface disposed at a pre-defined angle with a longitudinally extending axis of the stem. At least a second portion of the flat surface is provided with a plurality of protruding structures. At least one set of the plurality of protruding structures couples to at least one set of the plurality of the holes.
BRIEF DESCRIPTION OF DRAWINGS
[008] 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.
[009] Fig. 1 depicts an exploded view of an implant 100, according to an embodiment of the present invention.
[0010] Fig. 2 depicts an isometric view of a head 110 of the implant 100, according to an embodiment of the present invention.
[0011] Fig. 3 depicts an isometric view of a stem 120 of the implant 100, according to an embodiment of the present invention.
[0012] Figs. 4a-4d depicts coupling of the head 110 and the stem 120 of the implant 100 according to different embodiments of the present invention.
DETAILED DESCRIPTION OF DRAWINGS
[0013] 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.
[0014] 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.
[0015] 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.
[0016] 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.
[0017] The present disclosure relates to a shoulder implant (or implant). The implant is for replacing the native humeral head of the humerus bone. A stem portion (or stem) of the implant is inserted inside the humerus bone by reaming a canal in the humerus bone. And, a head portion (or head) is coupled to the stem portion with proper alignment irrespective of the anatomical variations of the shoulder joint (described later).
[0018] Though the coupling between the head portion and the stem portion of the present disclosure have been explained with the example of a shoulder implant, the teachings of the present disclosure are equally applicable to other implants (for example, hip implant, knee implant, etc.) and the same is within the scope of the teachings of the present disclosure.
[0019] Now referring to the figures, Fig. 1 illustrates an exploded view of an implant 100. The implant 100 includes at least two components, namely, a head portion (or head) 110 and a stem portion (or stem) 120. The implant 100 replaces, for example, the native humeral head of a shoulder joint.
[0020] The head 110 can be made from a material including, without limitation, titanium, cobalt chromium, SS316, etc. In an embodiment, the head 110 is made of cobalt chromium. The head 110 of the implant 100 can have a shape including, without limitation, elliptical, oval, spherical, semi-spherical, etc. In an embodiment, as depicted in Fig. 2, the head 110 is semi-spherical shaped with a dome 111 and a base 113.
[0021] An outer surface of the dome 111 of the head 110 includes a smooth surface to reduce inflammation. In an exemplary embodiment, the dome 111 has a shape and size corresponding to an anatomy of the glenoid cavity of a shoulder joint.
[0022] The base 113 can include, without limitation, a flat, curved, etc. structure. In an embodiment, as depicted in in Fig. 2, the base 113 is flat with rounded edges.
[0023] At least a first portion of the base 113 includes a plurality of holes 113a. The holes 113a can be arranged on the base 113 in a pre-defined pattern including at least one of a grid, spiral, honeycomb, wave, etc. In an embodiment, the holes 113a are arranged in a grid-like pattern. The first portion of the base 113 defines a surface area depending upon the bone anatomy of the patient population. The holes 113a of the base 113 helps to couple the stem 120 to the head 110 (described later).
[0024] Fig. 3 depicts the stem 120 of the implant 100. The stem 120 can be made from a material including, without limitation, titanium, cobalt chromium, SS316, etc. In an embodiment, the stem 120 is made of cobalt chromium. The dimensions of the stem 120 may vary depending upon the bone anatomy of the patient population.
[0025] The stem 120 includes, without limitation, a distal portion 121, and a proximal portion 123. The distal portion 121, and the proximal portion 123 may either form an integral structure or are removably coupled to each other. In an exemplary embodiment, the distal portion 121, the proximal portion 123 forms an integral structure.
[0026] The distal portion 121 have an elongated structure that is, without limitation, at least one of tapered, straight, flared, and curved. In an exemplary embodiment, as shown in Fig. 3, the distal portion 121 is tapered. The distal portion 121 has a length corresponding to an anatomy of the humerus bone.
[0027] In an exemplary embodiment, as shown in Fig. 3, the proximal portion 123 has a relatively larger diameter than the distal portion 121.
[0028] The proximal portion 123 may be provided with at least one axially extending cavity (or cavity) 123a. The cavity 123a helps in insertion and extraction of the stem 120.
[0029] The proximal portion 123 is provided with at least one flat surface 125 at a pre-defined angle (with respect to a longitudinally extending axis of the stem 120). The dimensions of the flat surface 125 may vary depending upon the bone anatomy of the patient population.
[0030] The flat surface 125 has a pre-defined shape including, but not limited to, circular, rectangular, square, oval, obround, triangular etc. In an embodiment, as shown in Fig. 3, the shape of the flat surface 125 is rectangular-like with curved edges. The flat surface 125 may define a second surface area. The dimensions of the flat surface 125 may vary depending upon the bone anatomy of the patient population. The second surface area of the flat surface 125 may either be less than or equal to the first surface area of the base 113 of the head 110. In an exemplary embodiment, the first surface area of the flat surface 125 is less than the second surface area of the base 113.
[0031] At least a second portion of the flat surface 125 includes a plurality of protruding structures 125a arranged in a pre-defined pattern for coupling the stem 120 to the head 110. The protruding structure 125a may be arranged in a pre-defined pattern corresponding to the pre-defined pattern of the holes 113a. The protruding structures 125a can be at least one of pegs, screws, hangers, hooks, spikes, etc. In an embodiment, as shown in Fig. 3, the protruding structures 125a include pegs. The protruding structures 125a may complement the shape of the holes 113a of the head 110.
[0032] The stem 120 and the head 110 are coupled using at least one set of the protruding structure 125a and at least one set of the holes 113a as shown in Figs. 4a-4d. At least one set of the protruding structures 125a includes a few of the protruding structures 125a from the plurality of the protruding structures 125a. At least one set of the holes 113a includes a few of the holes 113a from the plurality of the holes 113a. The coupling between the holes 113a and protruding structure 125a can be achieved by mechanisms such as at least one of press-fit, snap-fit, interference fit, expanding pegs, keyed fit, grid locking, etc. In an embodiment, the protruding structure 125a and the holes 113a are coupled via snap-fit mechanism. The second portion of the flat surface 125 of the stem 120 has a smaller surface area relative to the area of the first portion of the base 113, thus, the flat surface 125 can be coupled to at least a portion of the base 113 of the head 110 thereby giving a medical practitioner freedom to properly align the stem 120 with the base 113 (and the head 110 as well).
[0033] For example, if the canal reamed inside the humerus bone is not in aligned with the glenoid, which can happen due to different factors. These factors depend upon the bone quality which may be affected by natural bone density as the structure of bones may vary from individual to individual and also other medical condition that the person may be suffering from. The off-centred reamed canal can result in a misalignment between a head and a stem of a conventional implant. To overcome this misalignment, the head 110 and the stem 120 are coupled by the coupling mechanism as described above.
[0034] For example, Fig. 4a represents a left-aligned coupling of the stem 120 with respect to the head 110. Fig. 4b represents the right-aligned coupling of the stem 120 with respect to the head 110. Fig. 4c represents the top-aligned coupling of the stem 120 with respect to the head 110. Fig. 4d represents the bottom-aligned coupling of the stem 120 with respect to the head 110. The alignments as depicted in Figs. 4a-4d are only exemplary illustrations. The implant 100 provides the medical practitioner to choose from ‘n’ number of alignments to properly align the head 110 with the stem 120 of the implant 100 irrespective of the anatomical variations of the shoulder joint such that there is maximum possible bone coverage.
[0035] 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. A shoulder implant (100) comprising:
a. a head (110) having a base (113), at least a first portion of the base (113) is provided with a plurality of holes (113a);
b. a stem (120) having a proximal portion (123), the proximal portion (123) is provided with a flat surface (125) at a pre-defined angle with a longitudinally extending axis of the stem (120), at least a second portion of the flat surface (125) is provided with a plurality of protruding structures (125a);
wherein, at least a one set of the plurality of protruding structures (125a) couples to at least one set of the plurality of the holes (113a).
2. The shoulder implant (100) as claimed in claim 1, wherein the surface area of the first portion is larger than the second portion.
3. The shoulder implant (100) as claimed in claim 1, wherein the protruding structure (125a) are arranged in a pre-defined pattern corresponding to a pre-defined pattern of the holes (113a).
4. The shoulder implant (100) as claimed in claim 1, wherein the protruding structures (125a) are at least one of pegs, screws, hangers, hooks, and spikes.
5. The shoulder implant (100) as claimed in claim 1, wherein at least a few of the plurality of protruding structures (125a) couples to at least a few of the plurality of the holes (113a) via at least one of press-fit, snap-fit, interference fit, expanding pegs, keyed fit, or grid locking.