Interpositional spacer implant for treatment of rotator cuff tear

Abstract

An implant for attachment to a humerus and configured to retain a space between the humerus and an acromion is provided. The implant comprises a body having an ovoid articular surface configured to engage the acromion and an undersurface configured to attach to a superior aspect of the humerus at a lateral portion thereof. The implant is dimensioned to maintain the humeral head in a depressed position relative to the acromion, simulating the thickness of a previously existing rotator cuff, and may include fixation members and bone growth-promoting coatings. In one aspect, the implant includes at least one attachment point, the attachment point configured to receive a suture. In such an aspect, the implant may further include a cutout disposed underneath the attachment point. A method of repairing a shoulder using the implant described above is also provided. The method may be implemented to repair a damaged rotator cuff.

Description

Specification 263679-573249 INTERPOSITIONAL SPACER IMPLANT FOR TREATMENT OF ROTATOR CUFF TEAR CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority to U.S. Provisional Application No.63 / 689,466, filed August 30, 2024, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0002] The present disclosure relates generally to orthopedic implants and, more particularly,to an implant for attachment to the humerus for the treatment of shoulder supraspinatus tendon tears, including but not limited to cases involving massive rotator cuff tears. BACKGROUND

[0003] A rotator cuff tear is an injury to the muscles and tendons that stabilize the shoulderjoint. The rotator cuff comprises four tendons that maintain the humeral head in proper articulation with the glenoid. Injury or degeneration of these tendons can result in superior migration of the humeral head, leading to impingement with the acromion, pain, and loss of shoulder function. While some rotator cuff tears can be repaired surgically, massive tears—defined as those greater than 5 cm or involving two or more tendons—may be irreparable. In such cases, it is desirable to provide an implant that maintains or restores the subacromial space, prevents impingement, and restores shoulder function. In orthopedic shoulder reconstruction, particularly in the context of massive rotator cuff tears and subsequent arthropathy, the use of implants can have a significant impact on the function of the deltoid muscle, especially as it relates to the size and design of the implant in the region of the deltoid process.

[0004] The deltoid muscle is the primary elevator of the shoulder, especially when the rotatorcuff is deficient or irreparably torn. In cases of massive rotator cuff tears with severe tendon retraction and muscle atrophy, the deltoid becomes even more critical for shoulder function. The design and size of shoulder implants, particularly those that interact with or are positioned near the subacromial space, can directly influence the mechanical advantage and functional capacity of the deltoid muscle.Specification 263679-573249

[0005] When an implant is oversized or extends excessively into the region of the deltoidprocess, it can alter the normal biomechanics of the shoulder. For instance, an excessively large implant may change the deltoid’s lever arm. As is known, the deltoid muscle’s ability to generate force and produce shoulder elevation depends on its lever arm relative to the center of rotation of the shoulder joint. An implant that increases the lateral offset or alters the center of rotation can either enhance or diminish the deltoid’s mechanical advantage. If the implant is too large, it may over-tension the deltoid, leading to muscle fatigue, discomfort, or even impaired function.

[0006] An oversized implant may also generate impingement and / or affect the soft tissuebalance of the shoulder. The size and contour of the implant can restrict the normal excursion of the deltoid muscle, potentially leading to impingement or reduced range of motion. This is particularly relevant if the implant encroaches upon the space normally occupied by the deltoid or its tendon insertions. Proper soft tissue tension is essential for optimal shoulder function. An implant that is too large may disrupt the delicate balance between the deltoid and remaining shoulder musculature, leading to instability or suboptimal movement patterns.

[0007] Conversely, an implant that is appropriately sized and contoured to the patient’sanatomy can help restore or even improve the deltoid’s function. For example, in reverse- configuration total shoulder arthroplasty, the design intentionally medializes and lowers the center of rotation, thereby increasing the deltoid’s lever arm and compensating for the loss of rotator cuff function. However, even in this context, oversizing the implant can lead to excessive tension and potential complications. SUMMARY

[0008] An implant is provided for attachment to a humerus and configured to retain a spacebetween the humerus and an acromion. The implant includes a body having an articular surface configured to engage the acromion and an undersurface configured to attach to a superior aspect of the humerus at a lateral portion of the superior aspect. The body is ovoid in shape, having a mediolateral dimension greater than an anteroposterior dimension. The implant is configured such that, when attached, it retains a space between the humerus and the acromion.

[0009] In some implementations, the articular surface is inset into the humerus to provide asmooth transition from a cartilage, the cartilage proximate to the superior aspect, to the implant, without an abrupt step. In other examples, the articular surface has a continuous, smooth rise fromSpecification 263679-573249 a medial aspect to a superior peak, without any concavity or abrupt contour change. The body may extend laterally beyond a native bony margin of the humerus to increase the lateral offset and thereby enhance the deltoid muscle lever arm.

[0010] Optionally, the undersurface of the body is concave and configured to match a convex,prepared surface of the humerus, thereby enhancing stability and seating of the implant. In some examples, the implant further includes a bone growth-promoting coating on at least a portion of the undersurface of the body, wherein the growth-promoting coating is one of an ingrowth and an ongrowth.

[0011] The implant may further include a fixation member extending from the undersurfaceinto the superior aspect of the humerus. In some implementations, the fixation member includes a shaft and a fin, the fin extending radially from the shaft and tapering in a direction from the undersurface of the body to a distal end of the shaft. In certain examples, the shaft does not extend past a metaphysis of the humerus.

[0012] In some implementations, the width, measured from an anterior to a posterior of thebody, of the body may be smaller than a width of the humerus to allow preservation of anterior and posterior rotator cuff muscles by minimizing a required bone and / or soft tissue resection in those regions.

[0013] Optionally, the articular surface is formed of a cobalt-chrome-molybdenum alloy andthe undersurface includes a titanium plasma spray coating. In some implementations, the body is dimensioned such that, when attached, the body has a height that increases a height of the superior aspect of the humerus to simulate a thickness of a previously existing rotator cuff and maintain a humeral head in a depressed position relative to the acromion.

[0014] In certain examples, the articular surface includes at least three regions: a medial regionconfigured for smooth cartilage transition, a superior region forming a peak, and a lateral region, each having distinct radii of curvature. The medial region may include a distal portion and a proximal portion, the proximal portion configured to be disposed underneath a cartilage that is proximate to the superior aspect of the native articular region of the humerus, wherein the articular surface of the proximal portion tapers at a greater rate relative to the articular surface of the distal portion.

[0015] In some implementations, the implant is configured such that a transition from a lateralportion of a cartilage proximate to the superior aspect is a gradual incline relative to the articularSpecification 263679-573249 surface of the distal portion of the body, and a superior region of the body provides a humeral head depressor effect to prevent superior migration of the humerus. The lateral extension of the body may be dimensioned to increase a resting length of a deltoid muscle, thereby improving deltoid lever arm in the absence of a functional rotator cuff.

[0016] Optionally, the body is configured to be inset below a cartilage at a medial aspect,wherein the cartilage is proximate to the superior aspect, and wherein the body is dimensioned to rise smoothly to a peak at the superior aspect, with a lateral extension projecting beyond a native humeral margin.

[0017] In another aspect, an implant for attachment to a bone is provided. The implantincludes a body having an articular surface and an undersurface configured to attach to the bone. The body includes at least one attachment point configured to receive a suture. The attachment point is a through-hole extending from the articular surface to the undersurface along a curve.

[0018] In such an aspect the implant may include any one of the following features. Forinstance, the one attachment point may extend from one of an anterior aspect and a posterior aspect to the undersurface of the body. Optionally, the body may further include at least one cutout, the cutout is disposed underneath the attachment point. Additionally, the undersurface may include a bone growth-promoting coating on a portion of the undersurface of the body and the cutout is free of the bone growth-promoting coating.

[0019] In some implementations, the body further includes at least one cutout disposedunderneath the attachment point and the body is ovoid in shape, having a mediolateral dimension greater than an anteroposterior dimension. In such an implementation, the bone is a humerus and the implant is configured such that, when attached to the humerus, the articular surface of the body retains a space between the humerus and an acromion. The articular surface may have a continuous, smooth rise from a medial aspect to a superior peak, without any concavity or abrupt contour change.

[0020] A method of repairing a shoulder is also provided. The method includes providing animplant, the implant including a body having an articular surface configured to engage an acromion and an undersurface configured to attach to a superior aspect of a humerus at a lateral portion of the superior aspect, wherein the articular surface is ovoid in shape, having a mediolateral dimension greater than an anteroposterior dimension. The method further includes performing twoSpecification 263679-573249 reamings on a superior surface of a humerus and fixing the undersurface of the implant to the superior surface of the humerus at the two reamings.

[0021] In some implementations, the articular surface includes at least three regions: a medialregion configured for smooth cartilage transition, a superior region forming a peak, and a lateral region, each having distinct radii of curvature, and the method further includes the step of inserting the medial region of the body underneath a cartilage proximate the superior aspect.

[0022] In other examples, the implant includes a fixation member extending from theundersurface, the fixation member includes a shaft and a fin, the fin extending radially from the shaft and tapering from the undersurface of the body to a distal end of the shaft, and the method further includes the step of preparing the superior aspect by drilling a hole having a diameter smaller than a diameter of the shaft. Optionally, the articular surface has a continuous, smooth rise from a medial aspect to a superior peak, without any concavity or abrupt contour change. Optionally, the method may further include the step of forming a slit in a cortical of the humerus. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIG. 1 is a depiction of a healthy human shoulder joint;

[0024] FIG. 2 is a depiction of a human shoulder joint after rotator cuff tear and superiortranslation of humerus;

[0025] FIG. 3 is a view of a first aspect of a shoulder implant taken from an anterior aspect;

[0026] FIG. 4 is a top-down view of the implant shown in FIG. 3;

[0027] FIG. 5 is a perspective view of the undersurface of the implant shown in FIG. 3;

[0028] FIG. 6 is a plan view of the undersurface of the implant shown in FIG. 3;

[0029] FIG. 7A is view showing a human shoulder with the implant shown in FIG. 3;

[0030] FIG. 7B is a view of FIG. 7A with the arm raised to shoulder height;

[0031] FIG. 7C is a view of FIG. 7B with the arm raised above the shoulder;

[0032] FIG. 8A is a perspective view of the humeral head having a pair of reamings;

[0033] FIG. 8B is a lateral view of the humeral head with the implant shown in FIG. 3 fixedwithin the pair of reamings;

[0034] FIG. 9 is a cross-sectional view of FIG. 8B, taken along line 9-9 showing the implantpositioned underneath native cartilage;Specification 263679-573249

[0035] FIG. 10A is a view of a first aspect of a shoulder implant having suture holes takenfrom an anterior perspective;

[0036] FIG. 10B is a plan view of the undersurface of the implant shown in FIG. 10B;

[0037] FIG. 10C is a view of a first aspect of a shoulder implant having suture holes takenfrom a posterior and superior perspective;

[0038] FIG. 11 is a diagram showing the steps for a repairing a shoulder;

[0039] FIG. 12 is a bottom-up perspective view of a second aspect of an implant;

[0040] FIG. 13 is a top-down perspective view of the second aspect of an implant;

[0041] FIG. 14A is a view showing a human shoulder with the implant shown in FIG. 12;

[0042] FIG. 14B is a view of FIG. 14A with the arm raised to shoulder height;

[0043] FIG. 14C is a lateral view of the humeral head with the implant shown in FIG. 12;

[0044] FIG. 15 is a perspective view of a third aspect of an implant;

[0045] FIG. 16 is a cross-sectional view of the implant shown in FIG. 15 taken along line 16-16;

[0046] FIG. 17 is a perspective view of a fourth aspect of an implant attached to a glenoidtaken from a lateral aspect;

[0047] FIG. 18 is a perspective view the implant shown in FIG. 17 taken from a superioraspect;

[0048] FIG. 19 is a view of a fifth aspect of an implant configured to attach to a glenoid;

[0049] FIG. 20 is a view of FIG. 19 showing the implant in a closed position;

[0050] FIG. 21 is a view of the fifth aspect of an implant attached to a humeral head;

[0051] FIG.22 is a view of the fifth aspect of an implant having a clamping screw and attachedto a humeral head;

[0052] FIG. 23 is a view of the fifth aspect of an implant wherein the first and second arcuatemembers are elongated;

[0053] FIG. 24 is a view of FIG. 23 showing the operation of the clamping screw;

[0054] FIG. 25 is a view of the fifth aspect of an implant having a gripping feature;

[0055] FIG. 26 is a view of a sixth aspect of the implant attached to the glenoid taken from alateral aspect;

[0056] FIG. 27 is a view of FIG. 26 taken from a superior aspect;Specification 263679-573249

[0057] FIG. 28 is a perspective view of a seventh aspect of an implant taken from an inferioraspect;

[0058] FIG. 29 is a perspective view of the implant shown in FIG. 28 taken from a superioraspect;

[0059] FIG. 30 a perspective view of the implant shown in FIG. 28 taken from an anterioraspect;

[0060] FIG.31 is a perspective view of a seventh aspect of an implant having attachment pointstaken from an inferior aspect;

[0061] FIG. 32 is a perspective view of the implant shown in FIG. 31 taken from a superioraspect;

[0062] FIG. 33 a perspective view of the implant shown in FIG. 31 taken from an anterioraspect;

[0063] FIG.34 is a view of the implant shown in FIG.28 positioned to be attached to a humeralhead;

[0064] FIG. 35 is a top-down perspective view of an eighth aspect of an implant;

[0065] FIG. 36 is a plan view of the implant shown in FIG. 35;

[0066] FIG. 37 is a side view of the implant shown in FIG. 35;

[0067] FIG.38 is a view of the implant shown in FIG.35 positioned to be attached to a humeralhead;

[0068] FIG. 39 is a view of an eighth aspect of an implant taken from an inferior aspect;

[0069] FIG. 40 is a side view of the implant shown in FIG. 39;

[0070] FIG. 41 is a perspective view of the implant shown in FIG. 39;

[0071] FIG.42 is a view of the implant shown in FIG.39 positioned to be attached to a humeralhead;

[0072] FIG. 43 is a view of the implant shown in FIG. 39 attached to the humeral head;

[0073] FIG. 44 is an exploded view of a ninth aspect of an implant;

[0074] FIG. 45 is view of the implant shown in FIG. 44 in an assembled state;

[0075] FIG. 46 is a perspective view of the body of the implant shown in FIG. 44;

[0076] FIG. 47 is bottom-up view of FIG. 46;

[0077] FIG.48 is a view of the implant shown in FIG.44 positioned to be attached to a humeralhead; andSpecification 263679-573249

[0078] FIG. 49 is a view of the implant shown in FIG. 44 attached to the humeral head.

[0079] Corresponding reference numerals indicate corresponding parts throughout thedrawings. DETAILED DESCRIPTION

[0080] Example configurations will now be described more fully with reference to theaccompanying drawings. Example configurations are provided so that this disclosure will be thorough, and will fully convey the scope of the disclosure to those of ordinary skill in the art. Specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of configurations of the present disclosure. It will be apparent to those of ordinary skill in the art that specific details need not be employed, that example configurations may be embodied in many different forms, and that the specific details and the example configurations should not be construed to limit the scope of the disclosure.

[0081] The terminology used herein is for the purpose of describing particular exemplaryconfigurations only and is not intended to be limiting. As used herein, the singular articles “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. Additional or alternative steps may be employed.

[0082] When an element or layer is referred to as being “on,” “engaged to,” “connected to,”“attached to,” or “coupled to” another element or layer, it may be directly on, engaged, connected, attached, or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” “directly attached to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directlySpecification 263679-573249 between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items.

[0083] The terms “first,” “second,” “third,” etc. may be used herein to describe variouselements, components, regions, layers and / or sections. These elements, components, regions, layers and / or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example configurations.

[0084] The term “medial” is a directional term used to describe a position or direction towarda midline of the body, wherein the midline is an imaginary line that divides the body vertically into equal left and right halves. The term “lateral” is a direction away from the midline of the body. The term “Anterior” is a direction towards the front of the body. For example, a sternum a(breastbone) is anterior to a spine, and the kneecaps are on the anterior side of the legs. The term posterior is a direction opposite of the anterior. The term “Superior” means toward the head or the upper part of a structure and the term “inferior” is opposite of “superior”.

[0085] The present disclosure is directed to an orthopedic implant and associated surgicalmethod for treating shoulder instability, particularly in cases of irreparable rotator cuff tears. The implant is designed to be attached to the superior aspect of the humerus and to engage the acromion, thereby maintaining a subacromial space and preventing painful impingement.

[0086] With reference now to FIGS. 1-2, the implant 10 is configured to provide treatment ofa shoulder joint 100, which includes a humerus 102, an acromion 104, and a humeral-acromial space 106 which is the native space between a humeral head 108 and the acromion 104. FIG.1 depicts a healthy shoulder. Injury to the shoulder may cause the humerus 102 to move superiorly, resulting in a reduced humeral-acromial space 106 and impingement between the humerus 102 and acromion 104, as shown in FIG. 2. The implant 10 is configured to maintain the healthy humeral-acromial space 106 between the humerus 102 and the acromion 104.

[0087] With reference first to Figures 3-11, a first aspect of the implant 10 is provided. Theimplant 10 is configured to be fixed to the humerus 102. In particular, the implant 10 is configured to be attached to a superior-lateral aspect of the humeral head 108. The implant 10 includes a bodySpecification 263679-573249 12 formed of a material suitable and approved for medical use, such as a titanium or a metallic alloy such as cobalt-chromium, and a titanium alloy. The body 12 includes an articular surface 14 and an undersurface 16 opposite of the articular surface 14. The body 12 may be coated with a coating 34 formed of a material to promote osseointegration such as porous titanium, titanium nitrate, hydroxyapatite, ceramic coatings and the like. As shown in FIG.5, the coating 34 may be formed on the articular surface 14 and the undersurface 16. In some aspects, the coating 34 on the articular surface 14 is different than the coating on the undersurface 16. The body 12 may be formed as a solid unit. The articular surface 14 may be formed of a cobalt-chrome-molybdenum alloy, and the undersurface 16 may include a titanium plasma spray coating.

[0088] FIG. 3 is a side view of the implant 10 showing the anterior side of the implant 10.FIG. 4 is a top-down view of the implant 10 showing the articular surface 14. The body 12 is ovoid in shape, with a mediolateral dimension greater than its anteroposterior dimension as shown when viewing FIGS. 3 and 4 collectively. As used herein, the term “mediolateral” means a direction from the midline of a human body towards the outside of the human body and the term “anteroposterior” means a direction from the front of the human body towards the back of the human body, e.g. from the sternum at the front to the spine at the back. The articular surface 14 is convex with no concavities.

[0089] With reference now to FIGS. 7A-7C, the articular surface 14 is configured to engagethe acromion 104 and the undersurface 16 is designed to attach to the superior aspect of the humerus 102 at a lateral portion thereof. The articular surface 14 may be inset into the humerus 102 to provide a smooth transition from the undersurface 16 native cartilage 110 (shown in FIG. 9) to the implant 10, avoiding abrupt steps or contour changes. As used herein, the term “smooth” means that there are no abrupt deviations in the dimension of the surface which would result in structures such as an edge or a bump, thus the dimensions of the body 12 may change and still be “smooth”.

[0090] With reference again to FIG. 3, the articular surface 14 has a continuous, smooth risefrom a medial aspect to the lateral aspect, without concavity or abrupt contour change. The articular surface 14 may include at least three regions which are demarcated by lines 1-1 and 2-2. The area from line 2-2 to the medial aspect of the implant 10 is a medial region 18 for smooth cartilage 110 transition. The area between lines 1-1 and 2-2 is a superior region 20, and the area from line 1-1 to a lateral aspect is a lateral region 24. The superior peak 22 of the superior regionSpecification 263679-573249 20 when the implant 10 is implanted is configured to engage a proximal surface of the acromion 104 as shown in FIG. 7A. Each of the medial region 18, the superior region 20 and the lateral region 24 has a distinct radii of curvature about a longitudinal axis “A1” of the body 12 bisecting the body 12 into an anterior portion 26 and a posterior portion 28 as shown in FIG.4. The radii of curvature of each region may vary while maintaining the smooth and continuous surface of the body 12.

[0091] With reference again to FIG. 4, top-down view of the implant 10 is provided. The body12 is generally symmetrical about the longitudinal axis “A1” of the body 12, that is, the anterior portion 26 of the body 12 is symmetrical to the posterior portion 28 of the body 12. The proximal end of the medial region 18 and the distal end of the lateral region 24 are rounded. The proximal end of the medial region 18 has an edge that follows a radius that gradually increases from the anterior and lateral aspect of the proximal end to a midpoint of the medial region 18 so as to be generally hemi-spherical. The anterior and lateral aspect of the distal end of the lateral region 24 are arcuate and a middle portion of the distal end extends along an axis orthogonal to the longitudinal axis “A1” of the body 12 so as to form a flattened end with rounded corners. The width of the articular surface 14, measured from the anterior aspect to the posterior aspect, is smaller than the width of the humerus 102, as shown in FIG. 8B, allowing preservation of the anterior and posterior rotator cuff muscles by minimizing required bone resection in those regions. The width of the implant (medial to lateral) may be between 25% and 80% of the width of the humeral head for any patient, and 40% to 60% for most adult patients. The width may be between 10 and 4 millimeters, with the upper limit reflecting the largest practical tear size that the implant would address. The width of the implant 10 is selected to optimize the lever arm for the deltoid muscle. This allows the deltoid to function more effectively in the absence of a functional rotator cuff, improving the patient’s ability to lift and move the arm. Thus, in the case of a large tear, an implant 10 having a width at the greater range would be selected.

[0092] With reference again to FIG. 3 and now to FIG. 9, the medial region 18 may include adistal portion 30 and a proximal portion 32. The distal portion 30 is further away from the midline of the body 12 relative to the proximal portion 32. The proximal portion 32 is configured to be disposed underneath cartilage 110 proximate to the superior aspect of the native articular region of the humerus 102. FIG.9 shows the proximal portion 32 of the implant seated beneath the native cartilage 110 and an outer surface of the cartilage 110 and the outer surface of the proximal portionSpecification 263679-573249 32 of the body 12 form a contiguous and smooth transition. Thus, as the arm is moved, the cartilage 110 is not worn down or otherwise weakened during the movement of the arm.

[0093] The articular surface 14 of the proximal portion 32 tapers at a greater rate relative tothe articular surface 14 of the distal portion 30 so as to provide a transition from the lateral portion of the cartilage 110 to the articular surface 14 of the body 12 that is a gradual incline resulting in a smooth transition between the cartilage 110 and the articular surface 14 of the body 12. For example, the proximal portion 32 has an incline between 45 to 70 degrees relative to a plane of the undersurface 16 of the medial region 18 as indicated by Line A2 shown in FIG. 3, whereas the distal portion has an incline between 118 to 150 degrees relative to line A2. The articular surface of the lateral region 24 at the lateral aspect has an incline between 45 to 66 degrees relative to a plane of the undersurface 16 of the lateral region 24 as indicated by Line A3. The superior region 20 of the body 12 provides a humeral head depressor effect to prevent superior migration of the humerus 102. In particular, as shown in FIG. 7A, the superior peak 22 engages the proximal surface of the acromion 104 when the arm is in a resting position, e.g. hanging along the side of the body which prevents the acromion 104 from be depressed relative to a healthy human shoulder joint 100.

[0094] The superior region 20 of the body 12 has a lateral extension and a superior extensionthat is dimensioned to increase the resting length of the deltoid muscle, thereby improving the deltoid lever arm in the absence of a functional rotator cuff. That is, a width and a height of the superior region 20 of the body 12 is dimensioned to minimize the space that the body 12 occupies within the humeral-acromial space 106. The body 12 may be inset below the cartilage 110 at a medial aspect and rise smoothly to the superior peak 22 at the superior aspect, with a lateral extension projecting beyond the native humeral margin. The body 12 may extend laterally beyond the native bony margin of the humerus 102 to increase the lateral offset, thereby enhancing the deltoid muscle lever arm. In other words, a lateral portion of the body 12 projects outwardly from the natural dimension of the humerus 102 to occupy the humeral-acromial space 106. The body 12 is dimensioned such that, when attached, the body 12 increases the height of the superior aspect of the humerus 102 to simulate the thickness of a previously existing rotator cuff and maintain the humeral head 108 in a depressed position relative to the acromion 104.

[0095] With reference now to FIGS. 5 and 6, a depiction of the undersurface 16 of the body12 is provided. The undersurface 16 of the body 12 is preferably concave to match a convex,Specification 263679-573249 prepared surface of the humerus 102, enhancing stability and seating of the implant 10. The implant 10 may include a bone growth-promoting coating 34, such as an ingrowth or ongrowth surface, on at least a portion of the undersurface 16. The implant 10 may include a fixation member 36 fixedly attached to the undersurface 16. The fixation member 36 extends from the undersurface 16 and is configured to be inserted into the superior aspect of the humerus 102. The fixation member 36 includes a shaft 38 and a fin 40. The shaft 38 may be a generally conical member and is shown disposed on the undersurface 16 of the medial region 18 of the body 12. However, it should be appreciated that the shaft 38 may be disposed on the undersurface 16 of the superior region 20 or the lateral region 24. The fin 40 extends radially from the shaft 38 and tapers in a direction from the undersurface 16 of the body 12 to a free end of the shaft 38. In one aspect, the fin 40 ends at midpoint of the shaft 38. However, it should be appreciated that the fin 40 may be dimensioned to extend all the way to the free end of the shaft 38. In one aspect, the shaft 38 has a length dimensioned not to extend beyond a metaphysis of the humerus 102.

[0096] With reference now to FIGS. 7A-7C a description of the operation of the implant 10 isprovided. FIG.7A depicts the humerus 102 in a position where the arm is at the side of the body 12, illustrating the humeral head depressor effect. In particular, The superior peak 22 of the implant 10 is designed to maintain the humeral-acromial space 106, compensating for the loss of the rotator cuff (specifically the supraspinatus tendon). In the absence of the supraspinatus tendon, the humeral head 108 tends to migrate superiorly toward the acromion 104, leading to impingement and loss of function. The height and convexity of the implant is configured to act as a spacer, preventing this migration and maintaining joint congruity. Thus, it should be appreciated that a height of the implant 10 is designed to extend from the superior surface of the humeral head 108 to the acromion 104 between 3 to 10 millimeters, and thus the height (superior to inferior) of the implant 10 as measured from the superior peak 22 to the undersurface 16 may be between 4 and 15 millimeters. In other words, the thickness of the implant 10 to be implanted in a patient is selected to account for the depth of a reaming made during the preparation of the humeral head 108, as discussed in greater detail below.

[0097] FIG. 7B depicts the arm moved to shoulder height and FIG. 7C shows the arm raisedabove the shoulder. FIGS. 7A-7C illustrate how the superior region 20 of the implant 10 cooperates with the acromion 104 to maintain the humeral-acromial space 106, that is to keep the humeral head 108 spaced apart from the acromion 104. When the arm is positioned at the side ofSpecification 263679-573249 the body 12, the proximal end of the superior region 20 abuts against the acromion 104. As the arm is abducted (raised away from the body), the articular surface 14 allows for a smooth transition of contact from the superior peak 22 toward the lateral region 24 of the implant 10. The thickness of the articular surface 14 from the superior peak 22 to a lateral peak 24a declines at a first rate and the radius from the lateral peak 24a to the distal end of the lateral region declines at a second rate that is greater than the first rate. As shown in FIGS. 7B-7C, the implant 10 engages the acromion 104 along an area of the articular surface 13 from the superior peak 22 to the lateral peak 24a. The gradual decline in thickness, e.g. radius, from the superior peak 22 to the lateral peak 24a ensures that the humeral head 108 remains depressed and does not impinge on the acromion 104 throughout the range of motion. The thickness from the superior peak 22 to the lateral peak 24a also provides a predictable and stable articulation as the arm moves, facilitating natural shoulder kinematics. Further, the gradual decline in thickness avoids abrupt changes in curvature, which could otherwise lead to abnormal joint mechanics or increased wear.

[0098] With reference now to FIGS. 10A-10C, the implant 10 may further include anattachment point 46, the attachment point 46 is configured to receive a suture (not shown). In one aspect, the implant 10 includes at least a pair of attachment points 46 wherein one attachment point 46 is disposed on an anterior aspect of the implant 10 and the other attachment point 46 is disposed on the posterior aspect of the implant 10. For illustrative purposes, the implant 10 is shown as having six (6) attachment points 46, with three (3) attachment points on both the medial and lateral aspects of the implant 10. Each of the attachment points may be identical to the other. The attachment points are through-holes which are curved from a respective medial and lateral aspect to the undersurface 16 of the implant 10. The curvature of the attachment points 46 are configured to facilitate the introduction and reception of a curved needle for use in the suture process.

[0099] Underneath each of the attachment points 46 is a cutout 48. The cutout 48 is a recessformed to assist in passing sutures through or around the implant during fixation. In other words, the cutouts 48 provide a dedicated space for suture loops, making it easier for the surgeon to thread and secure sutures, whether they are placed before or after the implant 10 is seated. This feature is particularly valuable in complex shoulder repairs where secure fixation of soft tissue to the implant is critical for stability and healing. Further, the cutouts 48 help prevent suture damage. If sutures are placed before the implant 10 is impacted onto the bone, the cutouts 48 ensure that the sutures are not pinched, frayed, or severed by the edge of the implant 10 as it is seated. In oneSpecification 263679-573249 aspect, the cutouts 48 are intentionally left uncoated or clear of any surface treatments, such as a bone growth-promoting coating 34 that might otherwise abrade or cut the sutures to protect the integrity of the sutures, ensuring that the sutures remain strong and intact throughout the healing process. As shown in FIG.10B, the undersurface 16 includes bone growth-promoting coating 34 with the exception of an area surrounding each of the cutouts 48.

[0100] With reference now to FIG. 11, a method for repairing a shoulder is provided. Themethod begins at step 200 where an implant 10 is provided. The implant 10 includes a body 12that is ovoid in shape and includes an articular surface 14 for engaging the acromion 104 and an undersurface 16 configured for attachment to the superior aspect of the humerus 102. The method proceeds to step 202 where an incision is made at the shoulder to access a superior surface 112 of the humerus 102. This may be performed in a shoulder arthroscopic procedure. At step 202, two reamings, a medial reaming 42 and a lateral reaming 44, are made on the superior surface 112 of the humerus 102 to prepare the bone for implant 10 seating and fixation. As shown in FIG.8A, each of the medial reaming 42 and the lateral reaming 44 is generally circular and form a recess into the superior surface 112 to provide a shape of a snowman. The medial reaming 42 and the lateral reaming 44 may be recessed relative to the superior surface of the humeral head 108 a depth between 1 to 5 millimeters, thus the implant 10 may be selected based upon the height of the implant 10 or the depth of the reamings 42, 44 to achieve a desired extension beyond the superior aspect of the humeral head 108. For instance, should the reamings 42, 44 may be made at a depth of 3 millimeters, the implant 10 may be designed to have a height of 11 millimeters where the humeral-acromial space is 8 millimeters.

[0101] At step 204, the method includes fixing the undersurface 16 of the implant 10 to thesuperior surface 112 of the humerus 102 at the medial reaming 42 and the lateral reaming 44. The articular surface 14 has a continuous, smooth rise from the medial aspect of the medial region 18 to the superior peak 22 of the superior region 20, without any concavity or abrupt contour change.

[0102] At step 204, the medial region 18 of the body 12 is implanted onto the medial andlateral reamings 42, 44 as shown in FIG.9 and is inserted underneath the cartilage 110 proximate to the superior aspect of the humeral head 108 at the medial reaming 42 (as shown in FIG. 9), wherein the undersurface 16 of the body 12 may be attached to the humeral head 108 using any conventional attachment means currently known and later developed to include sutures, a combination of sutures and bone growth-promoting coating 34. The medial aspect of the medialSpecification 263679-573249 region 18 is positioned underneath the cartilage 110 that is proximate to the superior aspect of a native articular region of the humerus 102. As the proximal portion 32 tapers at a greater rate relative to the articular surface 14 of the proximal portion 32, a smooth transition is made between the outer surface of the cartilage 110 and the articular surface 14 of the proximal portion 32.

[0103] In aspects, where the implant 10 includes a fixation member 36 with a shaft 38 and afin 40, the method may include step 206, wherein the superior surface 112 of the humeral head 108 is prepared to receive the fixation member 36 by drilling a hole 43 having a diameter smaller than the diameter of the shaft 38 to ensure a secure press-fit. The hole 43 may include a slit portion 43a and a cylindrical portion 43b formed on the undersurface 16 of the medial region 18 of the body 12, as shown in FIG.8.

[0104] The method allows for the preservation of the anterior and posterior rotator cuffmuscles by minimizing bone resection and provides a stable, functional construct that maintains the humeral head 108 in a depressed position relative to the acromion 104.

[0105] With reference now to FIGS. 12-14C, a second aspect of an implant 10a is provided.The implant 10a has a body 12a having an undersurface 16a and an articular surface 14a. The body 12a is a disc shaped member wherein the articular surface 14a includes a transitional edge 50 extending along a periphery of the body 12a and the superior surface of the body 12a is generally planar. The transitional edge 50 has a constant radius along the periphery of the body 12a. Protruding from the undersurface 16a is a fixation member 36a. The fixation member 36a includes a central shaft 52 and two peripheral pegs 54. The central shaft 52 is disposed at a center of the undersurface 16a of the body 12a and the peripheral pegs 54 extend equidistant from the central shaft 52. The central shaft 52 and the peripheral pegs 54 are configured to anchor the implant 10a to the humeral head 108. As shown in FIG.13, the transitional edge 50 that enables smooth articulation with the acromion 2.

[0106] FIGS. 14A-14C show the implant 10a is fixed to the humeral head 108. Bone cementmay be used to enhance fixation. Alternatively, the undersurface 16 may be porous and facilitate biologic fixation. As shown in FIG.14B, when the arm is raised, the implant 10a remains fixed to the humerus 102 and maintains a space between the humerus 102 and the acromion 104. The implant 10a increases the humeral-acromial space 106 and eliminates painful bone-on-bone impingement. FIG.14C shows the implant 10a covers a region of the humerus 102 known as theSpecification 263679-573249 greater tuberosity and prevents impingement with the acromion 2 by maintaining the humeral- acromial space 106.

[0107] With reference now to FIGS. 15-16, a third aspect of the implant 10b is provided. Inthe second aspect, the implant 10b is also configured to be fixed to the humerus 102. In such an aspect, the implant 10b the body 12b includes a thin region 56A and a thick region 56B. The thick region 56B has a generally cuboidal shape. The articular surface 14b of the body 12b is arcuate and extends along a generally constant radius from the medial aspect to the lateral aspect of the body 12b. The thin region 56A defines a lip that extends around a periphery of the thick region 56B. The thick region 56B protrudes upwardly relative to the thin region 56A and is configured to engage the acromion 104 (not shown) while the thin region 56A is configured to be fixed to the humerus 102. The implant 10b may include at least one attachment point 46 for fixing the implant 10b to the humerus 102. The attachment points 46 may be circular shaped through holes configured to accommodate a bone screw or sutures.

[0108] With reference now to FIG. 16 is a cross-sectional view of the implant 10b attached tothe humeral head 108. The attachment points 46 are fixed by sutures 114 and suture anchors 116 to the humerus 102. The implant 10b may be formed of a flexible material so as to conform to the humerus 102. Any flexible material suitable for surgical procedures currently known or later developed may be used herein, illustratively including a medical grade titanium steel or polymeric materials such as polyethylene, Polyetheretherketone, Polycarbonate urethane, or polypropylene.

[0109] With reference now to FIGS. 17 and 18, a fourth aspect of the implant 10c is provided.In the fourth aspect, the implant 10c is configured to be fixed to the glenoid 118. The implant 10c has a body 12c that is a plate of material having a thickness configured to maintain a predetermined space between the acromion 104 and the humerus 102, wherein the articular surface 14c of the body 12c is configured to engage the acromion 104 and the undersurface 16c of the body 12c is fixed to the glenoid 118. The implant 10c includes a pair of attachment points 46 configured to receive a pair of fasteners 58 configured to be screwed into the glenoid 118. The implant 10c may be formed as a rigid or flexible member. For instance, the implant 10c may be made of a medical grade titanium steel or polymeric materials such as polyethylene, Polyetheretherketone, Polycarbonate urethane, or polypropylene. Materials are selected based on their known long term implantation performance, and material characteristics in arthroplasty implant systems. In suchSpecification 263679-573249 an aspect, the implant includes at least one attachment point 46 configured to receive an attachment device such as a bone screw or sutures for fixing the implant to the glenoid.

[0110] With reference now to FIGS. 19-25, a fifth aspect of the implant 10d is provided. Inthe fifth aspect, the implant 10d includes a first arcuate member 60 rotatably attached to a second arcuate member 62 so as to define a clamp. FIGS. 19-25 illustrate an aspect where the implant 10d is attached to the glenoid 118. FIGS.19-25 illustrate that the shape of the first arcuate member 60 and the second arcuate member 62 are generally arcuate but may have different shapes. For instance, FIGS.19-22 show an aspect where the first and second arcuate members 60, 62 form a circle when closed onto each other. FIGS.23-25 provide an example where the first and second arcuate members 60, 62 are elongated and flattened relative to the first and second arcuate members 60, 62 shown in FIGS.19-22 so as to form a generally horseshoe shape when closed onto the glenoid 118. It should be appreciated that the implant 10d may be attached using a fastener 58 (not shown) such as a bone screw or sutures and that any fastener 58 currently known or later developed may be modified for use herein. For instance, a suture may be in the form of an infinity loop to close the ends of the first and second arcuate members 60, 62 onto the glenoid 118. That is to say, any fastener currently known or later developed may be modified for use with any aspects of the implant 10d described herein.

[0111] FIGS. 19-21 illustrate an aspect where the implant 10d includes a pin 64 pivotablycoupling a first end 60a of the first arcuate member 60 to a second end 62b of the second arcuate member 62. A second end 60b of the first arcuate member 60 is configured to grip to a second end 62b of the second arcuate member 62. FIG.19 shows the first and second arcuate members 60, 62 in an open position. The second end 62b of the second arcuate member 62 has a tooth 66 and the second end 60b of the first arcuate member 60 includes a groove (hidden from view) which is configured to lock with the tooth 66 as shown in FIGS. 20 and 21. FIG. 20 shows the first and second arcuate members 60, 62 closed onto the glenoid 118 and FIG.21 shows the first and second arcuate members 60, 62 closed onto the humeral head 108.

[0112] FIGS. 22-25 illustrate an aspect where the implant 10d is using a clamping screw 68.The first end 60a, 62a of the first and second arcuate members 60, 62 are pivotably connected to each other about the pin 64. The clamping screw 68 is connected to the first end 60a, 62a of the first and second arcuate members 60, 62 wherein a rotation of the clamping screw 68 in a first direction cooperates with the pin 64 to pull the first ends 60a, 62a together so as to push the secondSpecification 263679-573249 ends 60b, 62b away from each other opening the first and second arcuate members 60, 62. A rotation of the clamping screw 68 in a second direction, opposite of the first direction cooperates with the pin 64 to draw the first ends 60a, 62a of the first and second arcuate members 60, 62 away from each, pulling the second ends 60b, 62b towards each other, closing the first and second arcuate members 60, 62 onto each other so as to secure the implant 10d onto the humeral head 108 as shown in FIG.22 and onto the glenoid 118 as shown in FIG.23.

[0113] In accordance with the fifth aspect of the implant 10d, the first and second arcuatemembers 60, 62 may be closed onto each other using the concept of a tooth 66 and a groove, or a clamping screw 68. However, it should be appreciated that the implant 10d may be attached to the humeral head 108 using a suture. For instance, the suture may be sewn on using an infinity loop. Further it should be appreciated that the first and second arcuate and may be shaped so as to approximate the humeral anatomy. FIG.25 depicts an example where the undersurface 16d of the first and second arcuate members 60, 62 includes a gripping feature 70 configured to engage the humeral head 108 or the glenoid 118 as the case may be. The gripping feature 70 may be a set of teeth or otherwise jagged edges configured to find purchase with the corresponding humeral head 108 or the glenoid 118.

[0114] With reference now to FIGS. 26 and 27, a sixth aspect of the implant 10e is providedwherein the implant 10e is configured to be attached to a neck 120 of the glenoid 118. In such an aspect, the implant 10e has a body 12e that is a plate shaped member having a first contact member 72 and a second contact member 74 that are interconnected to each other by a neck portion 76. The implant 10e may be formed of a rigid and durable material suitable for interbody use, such as medical grade titanium or stainless steel. The neck portion 76 is arcuate so as to position the first contact member 72 into engagement with the acromion 104 and the second contact member 74 is attached to the neck 120 of the glenoid 118. The second contact member 74 may include attachment points 46 configured to receive fastener 58 so as to secure the second contact member 74 to the glenoid 118. Though the second contact member 74 is shown as having a generally planar surface that contacts the glenoid 118, it should be appreciated that the surface of the second contact member 74 contacting the glenoid 118 may be shaped to conform to the surface of the glenoid 118 such as the neck 120 of the glenoid 118, that is to say the undersurface 16e may be formed to be arcuate and / or undulating.Specification 263679-573249

[0115] With reference now to FIGS. 28-34, a seventh aspect of the implant 10f is provided.The implant 10f has a body 12f that is arcuate along a direction from a medial to a lateral aspect of the body 12f to form an undersurface 16f for attachment to the humerus as shown in FIG. 34 and an articulate surface 14f for engagement with the acromion 104 (not shown). The body 12f has a width as defined by an axis “A3” (shown in FIG.29) extending from an anterior aspect to a posterior aspect of the body 12f that tapers from the medial aspect to the lateral aspect of the body 12f. In one example, the implant 10f includes a fixation member 36f disposed on the undersurface 16f of the body 12f. For illustrative purposes, the fixation member 36f are three pegs for anchoring the implant 16f onto the humerus 102. It should be appreciated that the concave surface need not be uniform or need not have a constant radius but may be dimensioned to conform to the superior surface of the humerus 102. FIG.34 depicts the superior surface of the humeral head 108 without any preparation. However, it should be appreciated that the superior surface of the humeral head 108 may be prepared by a resection and holes may be drilled into the humeral head 108 to receive the fixation member 36f. In another example, ss shown in FIGS.31-33, the implant 10f does not include the fixation member 36f but includes a plurality of attachment points 46f for receiving an attachment mechanism 68f. FIGS.31-33 depict an aspect where five (5) attachment points 46f are formed on the body 10f; however, it should be appreciated that the number of positions of the attachment points 46f are provided for illustrative purposes and are not limiting to the scope of the appended claims.

[0116] With reference now to FIGS. 35-38 an eighth aspect of the implant 10g is provided.The implant 10g is configured to attach to the humerus 102. In such an aspect, the implant 10g has a body 12g that is a disk-shaped member having a thickness configured to retain a predetermined humeral-acromial space 106. The implant 10g is illustratively shown as being attached to the greater tuberosity of the humerus 102. However, it should be appreciated that the implant 10g may be attached to other locations of the humerus 102. Though the implant 10g is shown as having a pair of attachment points 46f for receiving a fastener 58, it should be appreciated that the implant 10g may be configured to include a fixation member 36f, such as a peg, instead of attachment points 46f.

[0117] With reference now to FIGS. 39-43, a nineth aspect of an implant 10h configured toattach to the humerus 102 is provided. In such an aspect, the implant 10h is configured to attach to the greater tuberosity of the humerus 102. The humerus 102 may be prepared by resection (asSpecification 263679-573249 shown in FIG.42) wherein a portion of the greater tuberosity of the humerus is excised to form a depression configured to receive the implant 10h, allowing the implant 10h to be seated within the depression. The implant 10h includes a body 12h that is a disk-shaped member. The implant 10h includes a seat portion 78 that protrudes from the undersurface 16h. The seat portion 78 has a diameter “D1” that is smaller than a diameter “D2” of the body 12h. The seat portion 78 is illustratively shown as a cylindrical member, but may be shaped otherwise, such as cuboidal or an irregular three-dimensional shape. A peripheral surface of the seat portion 78 may include a radial slit 80 configured to help retain purchase within the humeral head 108 when implanted.

[0118] The implant 10h includes a fixation member 36h, such as a peg which is integrallyformed or otherwise fixed to the undersurface 16h of the seat portion 78. The fixation member 36h may include a protrusion 82 extending along a longitudinal axis of the fixation member 36h. The protrusion 82 is disposed on the outer surface of the fixation member 36h and assists with finding purchase within the humeral head 108. In one aspect, the fixation member 36h includes a plurality of protrusions 82, each equidistant from each other and may have a uniform thickness along the outer surface of the fixation member 36h.

[0119] With reference now to FIGS.42 and 43, a description of the implantation of the implant10h is provided. The humeral head 108 is prepared by performing a resection wherein a first recess 84 is formed in the humeral head 108 and a second recess 86 is formed within the first recess 84. The second recess 86 may be centered within the first recess 84. The first recess 84 has a diameter “D3” that is slightly smaller than the diameter “D2” of the body 12h of the implant 10h and the second recess 86 has a diameter “D4” that is slightly smaller than the diameter “D1” of the seat portion 78, so as to receive the body 12h and the seat portion 78 in a tight-fit manner. In one aspect, a bore (not shown) having a diameter slightly smaller than the diameter of the fixation member 36h is drilled into the humeral head 108.

[0120] As shown in FIGS. 42 and 44, the fixation member 36h is inserted into bore drilled intothe second recess 86, and the seat portion 78 is fitted into the second recess 86 placing the body 12h into the first recess 84 so as to secure the implant 10h to the humeral head 108 and the articular surface 14h of the implant 10h extends beyond the superior surface of the humerus 102 so as to retain a predetermined humeral-acromial space 106. It should be appreciated that the implant 10h may be modified to replace the fixation member 36h with fastener 58h (not shown), in which case, the implant 10h would include an attachment point 46h (not shown). That is, the attachment pointSpecification 263679-573249 46h is a through-hole configured to accommodate the fastener 58h, such as a bone screw or a suture.

[0121] With reference now to FIGS.44-49 a tenth aspect of an implant 10i configured to attachto the humerus 102 is provided. The implant 10i is modular component and includes a fixation member 36i and a body 12i. In such an aspect, fixation member 36i is configured as a screw-in- anchor that is configured to attach to superior aspect of the humeral head 108, wherein an outer surface of the fixation member 36i is threaded. The body 12i is detachably connected to the fixation member 36i. A diameter of the body “D2” is larger than a diameter “D5” of the superior end of the fixation member 36i. The superior end of the fixation member 36i includes at least one stud 88 and the undersurface 16i of the body 12i includes an aperture 90 (shown in FIG. 47) configured to receive the stud 88 in a tension-fit manner. In one aspect, a free end of the studs 88 are bulbous and has a diameter that is slightly larger than shaft of the stud and slightly larger than a diameter of the aperture to which it is configured to be seated in. For illustrative purposes, the implant 10i is shown as having three studs 88 on the superior end of the fixation member 36i and the body 12i includes three apertures 90 on the undersurface 16i of the body 12i.

[0122] With reference now to FIGS.48 and 49, a description of the implantation of the implant10i is provided. The humeral head 108 is prepared by performing a resection wherein a first recess 84 is formed in the humeral head 108 and a second recess 86 is formed within the first recess 84. The second recess 86 may be centered within the first recess 84. The first recess 84 has a diameter “D3” that is slightly smaller than the diameter “D2” of the body 12h of the implant 10h and the second recess 86 has a diameter “D4” that is slightly smaller than the diameter “D5” of the fixation member 36i, so as to receive the body 12i and the fixation member 36i in a tight-fit manner. The implant 10i is implanted in a fully assembled state wherein the studs 88 of the fixation member 36i are inserted into the apertures 90 of the body 12i and the implant 10i is screwed into the second recess 86 until the undersurface 16i of the body 12i is pressed against the first recess 84, as shown in FIG.49.

[0123] A number of implementations have been described. Nevertheless, it will be understoodthat various modifications may be made without departing from the spirit and scope of the disclosure. Accordingly, other implementations are within the scope of the following claims.

[0124] The foregoing description has been provided for purposes of illustration anddescription. It is not intended to be exhaustive or to limit the disclosure. Individual elements orSpecification 263679-573249 features of a particular configuration are generally not limited to that particular configuration, but, where applicable, are interchangeable and can be used in a selected configuration, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.

Claims

Specification 263679-573249 CLAIMS1. An implant for attachment to a humerus and configured to retain a space between the humerusand an acromion, the implant comprising: a body having an articular surface configured to engage the acromion and an undersurface configured to attach to a superior aspect of the humerus at a lateral portion of the superior aspect; wherein the body is ovoid in shape, having a mediolateral dimension greater than an anteroposterior dimension; and wherein the implant is configured such that, when attached, it retains a space between the humerus and the acromion.

2. The implant as set forth in claim 1, wherein the articular surface is inset into the humerus toprovide a smooth transition from a cartilage to the implant, without an abrupt step, wherein the cartilage is proximate to the superior aspect of the humerus.

3. The implant as set forth in claim 1, wherein the articular surface has a continuous, smooth risefrom a medial aspect to a superior peak, without any concavity or abrupt contour change.

4. The implant as set forth in claim 1, wherein the body extends laterally beyond a native bonymargin of the humerus to increase the lateral offset and thereby enhance deltoid muscle lever arm.

5. The implant as set forth in claim 1, wherein the undersurface of the body is concave andconfigured to match a convex, prepared surface of the humerus, thereby enhancing stability and seating of the implant.

6. The implant as set forth in claim 1, further including a bone growth-promoting coating on atleast a portion of the undersurface of the body, wherein the bone growth-promoting coating is one of an ingrowth and an ongrowth.

7. The implant as set forth in claim 1, further including a fixation member extending from theundersurface and configured to be inserted into the superior aspect of the humerus.Specification 263679-5732498. The implant as set forth in claim 7, wherein the fixation member includes a shaft and a fin, thefin extending radially from the shaft and tapers in a direction from the undersurface of the body to a distal end of the shaft.

9. The implant as set forth in claim 8, wherein the shaft does not extend past a metaphysis of thehumerus.

10. The implant as set forth in claim 1, wherein a width, measured from an anterior to a posteriorof a human body, of the body is smaller than a width of the humerus to allow preservation of an anterior and a posterior rotator cuff muscles by minimizing a required bone and / or soft tissue resection in those regions.

11. The implant as set forth in claim 1, wherein the articular surface is formed of a cobalt-chrome-molybdenum alloy and the undersurface includes a titanium plasma spray coating.

12. The implant as set forth in claim 1, wherein the body is dimensioned such that, when attached,the body has a height that increases a height of the superior aspect of the humerus to simulate a thickness of a previously existing rotator cuff and maintain a humeral head in a depressed position relative to the acromion.

13. The implant as set forth in claim 1, wherein the articular surface includes at least three regions:a medial region configured for smooth cartilage transition, a superior region forming a peak, and a lateral region, each having distinct radii of curvature.

14. The implant as set forth in claim 13, wherein the medial region includes a distal portion and aproximal portion, the proximal portion configured to be disposed underneath a cartilage that is proximate to the superior aspect of a native articular region of the humerus, wherein the articular surface of the proximal portion tapers at a greater rate relative to the articular surface of the proximal portion.Specification 263679-57324915. The implant as set forth in claim 14, wherein the implant is configured such that a transitionfrom a lateral portion of a cartilage proximate to the superior aspect is a gradual incline relative to the articular surface of the distal portion of the body, and a superior region of the body provides a humeral head depressor effect to prevent superior migration of the humerus.

16. The implant as set forth in claim 1, wherein a lateral extension of the body is dimensioned toincrease a resting length of a deltoid muscle, thereby improving deltoid lever arm in an absence of a functional rotator cuff.

17. The implant as set forth in claim 1, wherein the body is configured to be inset below a cartilageat a medial aspect, wherein the cartilage is proximate to the superior aspect, and wherein the body is dimensioned to rise smoothly to a peak at the superior aspect, with a lateral extension projecting beyond a native humeral margin.

18. An implant for attachment to a bone, the implant comprising:a body having an articular surface and an undersurface configured to attach to the bone; and wherein the body includes at least one attachment point, the attachment point configured to receive a suture, wherein the attachment point is a through-hole extending from the articular surface to the undersurface along a curve.

19. The implant as set forth in claim 18, wherein the at least one attachment point extends from one of an anterior aspect and a posterior aspect to the undersurface of the body.

20. The implant as set forth in claim 19, wherein the body further includes at least one cutout, the at least one cutout disposed underneath the at least one attachment point.

21. The implant as set forth in claim 20, wherein the undersurface includes a bone growth- promoting coating on at least a portion of the undersurface of the body and the at least one cutout is free of the bone growth-promoting coating.Specification 263679-573249 22. The implant as set forth in claim 18, wherein the body further includes at least one cutout, the at least one cutout disposed underneath the at least one attachment point and the body is ovoid in shape, having a mediolateral dimension greater than an anteroposterior dimension; and wherein the bone is a humerus and the implant is configured such that, when attached to the humerus, the articular surface of the body retains a space between the humerus and an acromion.

23. The implant as set forth in claim 22, wherein the articular surface has a continuous, smooth rise from a medial aspect to a superior peak, without any concavity or abrupt contour change.

24. A method of repairing a shoulder comprising the steps of: providing an implant, the implant including a body having an articular surface configured to engage an acromion and an undersurface configured to attach to a superior aspect of a humerus at a lateral portion of the superior aspect, wherein the articular surface is ovoid in shape, having a mediolateral dimension greater than an anteroposterior dimension; performing two reamings on a superior surface of a humerus; and fixing the undersurface of the implant to the superior surface of the humerus at the two reamings.

25. The method as set forth in claim 24, wherein the articular surface includes at least three regions: a medial region configured for smooth cartilage transition, a superior region forming a peak, and a lateral region, each having distinct radii of curvature, and further including the step of inserting the medial region of the body underneath a cartilage proximate the superior aspect.

26. The method as set forth in claim 25, wherein the implant includes a fixation member extending from the undersurface, the fixation member includes a shaft and a fin, the fin extending radially from the shaft and tapers from the undersurface of the body to a distal end of the shaft, the method further including the step of preparing the superior aspect by drilling a hole having a diameter smaller than a diameter of the shaft.Specification 263679-573249 27. The method as set forth in claim 26, wherein the articular surface has a continuous, smooth rise from a medial aspect to a superior peak, without any concavity or abrupt contour change.

28. The method as set forth in claim 26, further including the step of forming a slit in a cortical of the humerus.

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