Patent ID: 12193939

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

This application is directed to enhanced reversible shoulder implants that better serve patients and the surgeons who implant them. The enhanced reversible shoulder implants can be deployed without a separate tray or adapter in a reverse configuration. The enhanced reversible shoulder implants can be made patient specific in some embodiments such that the implants provide excellent fit and also eliminate the need to size for a specific patient during the surgery. In other embodiments, a portion of a shoulder joint assembly can be fit to a patient by selection or use of a component that can adjust soft tissue tension in one or more directions relative to the shoulder joint. A portion of a shoulder joint assembly can be fit to a patient to increase tension in a medial-lateral direction (e.g., of rotator cuff tissue) without changing tension in an inferior-superior direction (e.g., of the deltoid muscle). A portion of a shoulder joint assembly can be fit to a patient to increase tension in an inferior-superior direction (e.g., of the deltoid muscle) without changing tension in a medial-lateral direction (e.g., of rotator cuff tissue). The tension-adjusting component can be patient generic or patient specific. These improvements can greatly simplify the kits supplied for a surgery as well as reducing waste and systems to recover and refurbish un-used components of kits.

I. Shoulder Anatomy

FIG.1shows anatomy of a glenohumeral joint. The joint is formed in part by a head10of a humerus12and a glenoid18of a scapula14. The head10is located at the superior end the humerus and includes a convex articular structure that is generally spherical. The glenoid18includes a concave articular surface upon which the convex surface of the head10moves.FIG.1Ashows that the humerus has a medial side (right side in the view) and a lateral side (left side in the view). The proximal humerus PH includes the head10and a portion of the humerus distal the neck. The distal humerus D is located between the proximal humerus and the elbow end of the humerus. The proximal humerus is also superior to the distal humerus D. The elbow end of the humerus is also inferior to the proximal humerus PH.

II. Humeral Stem Innovations

Various humeral component and method innovations are discussed herein. Various methods of making humeral components patient specific are discussed below. Embodiments of inventive humeral components that are, in some embodiments, well adapted for patient specific applications are discussed below. As discussed further below, patient specific shoulder, e.g., humeral, components can be made by obtaining imaging of a relevant bone, e.g., of a humerus, a glenoid or other scapular region to be replaced and/or in some cases of a bone being treated on an opposite side of the shoulder joint. That imaging can be obtained any time, such as in a portion of a pre-operative analysis of the patient but even intra-operatively in some cases. The imaging can include 3D imaging as can be captured using MRI, CT scan, X-ray imaging or similar technologies. That imaging can be used to inform the specific configuration of portions of one or more implants as discussed below to provide improved performance including, for example, improved fit, bone integration, soft tissue tensioning, and reduction in dislocation risk. In Sections II(A)-II(D) below, a number of strategies to make a reversible shoulder implant are discussed. In Section III below a number of strategies to make a humeral component patient specific are discussed, with a focus on reversible patient specific humeral implant.

A. Hollow Humeral Stem Improvements

FIG.2shows a humeral implant90according to one embodiment disclosed herein. The humeral implant90includes a humeral stem100and a reverse articular body250. The humeral stem100is shown embedded in the humerus12. An example procedure for positioning the humeral stem100in the humerus12is discussed below in connection withFIGS.16-18. The humeral stem100is generally disposed in a portion of the proximal humerus PH adjacent to a resection surface, which is formed in the method of implanting. The humeral stem100includes an inferior edge108and a mounting end112. The inferior edge108can be sharp to assist in implanting the humeral stem100as discussed further below. The sharp inferior edge108is located at an inferior or distal end of the humeral stem100. Also, the humeral stem100can include a hollow shaft104, which also assist in implanting the humeral stem100.

The mounting end112is located on a superior or proximal end of the humeral stem100. The mounting end112can be generally bowl shaped. In some cases, the mounting end112has an inferior curvature that can be characterized by a radius of curvature. The mounting end112can have a superior end that can be generally planar as indicated byFIG.7. In some cases, the superior end of the humeral stem100is angled medially and the inferior end of the humeral stem100is angled laterally.

The humeral stem100can be made to couple directly with an anatomic articular body and also to directly couple with a reverse configuration articular body.FIG.3shows that in one embodiment the humeral stem100has a mounting hole116and also has a mounting channel120. The mounting hole116is discussed further below. The mounting channel120includes an annular space that is exposed and accessible during the shoulder replacement procedure at the mounting end112.FIG.5shows that the mounting channel120can be disposed between an outer wall121and an inner wall122. In one embodiment, the mounting channel120extends entirely around the inner wall122to include a complete annular space. The mounting channel120can have other shapes, such as having one, two, three, or four discrete arcuate zones that are separated by radial walls. The mounting channel120could be one or more radial spaces rather than a circumferential space as illustrated inFIGS.3-5. As discussed further below, the mounting channel120can include a locking mechanism160. The locking mechanism160can be disposed at the outer wall121, e.g., integrally formed with or extending from the outer wall121as illustrated inFIG.9. In other embodiments the locking mechanism160can be disposed at the inner wall122, e.g., integrally formed with or extending from the inner wall122. The locking mechanism160can be disposed at the outer wall121and at the inner wall122in some embodiments, e.g., integrally formed with or extending from the outer wall121and from the inner wall122.

In some variations, the mounting channel120is disposed around, e.g., surrounds the mounting hole116. The mounting hole116can be defined by a portion of the inner wall122that faces a central zone of the mounting end112. In one embodiment, the outer wall121and the inner wall122comprise circular peripheries that surround a common center. A portion of the inner wall122that faces the common center can surround the mounting hole116. A portion of the inner wall122that faces the common center can define the mounting hole116. In one embodiment, an inside surface122aof the inner wall122is configured for mating with an anatomic articular body208. For example, the inside surface122acan be tapered, e.g., having a progressively smaller diameter along a length between a superior end of the humeral stem100and the inferior end thereof, e.g., from an opening into the mounting hole116to the transverse wall123. Engagement of the anatomic articular body208with the mounting hole116at the mounting end112can be by an interference fit, such as by a Morse taper as discussed further below.

The hollow shaft104can have a form that is suitable for a patient. The form of the hollow shaft104can include a shape as defined along a longitudinal axis124. For example, the hollow shaft104can be elongate along the longitudinal axis124. The hollow shaft104can have a curvature along the longitudinal axis124. As discussed further below a degree of curvature of the longitudinal axis124can be sized for classes of patient or can be patient specific based on an analysis of 3D imaging of a same curvature in the humerus of the patient. A patient specific curvature, e.g., radius, can be defined as corresponding to the curvature between the hollow shaft104and the mounting end112that best fits a characteristic such as providing enhanced bone filling or engagement or providing enhanced range of motion. This fit can be based on 3D imaging of the specific patient for which the humeral stem100is made.

The form of the hollow shaft104also can include a length132and a diameter136. The length132can be a dimension as measured from the inferior edge108to the location of a base133of the mounting end112.FIG.6shows that due to the orientation of the mounting end112relative to the hollow shaft104the length132defined on the inside of the curvature of the longitudinal axis124(also on the medial side of the humeral stem100) is less than a similar length on the outside of the curvature of the longitudinal axis124(also on the lateral side of the humeral stem100). AlthoughFIG.6shows the length132as measured on the medial side of the humeral stem100the length132could be measured on the lateral side. In some techniques, the length on the lateral side is more critical. In some cases, the length on the lateral side follows from defining the orientation of the mounting end112(e.g., of a plane intersecting the superior end of the mounting end112) and by defining the length132on the medial side of the humeral stem100.

The form of the hollow shaft104can also be in part defined by a diameter136of the shaft104. The diameter136can be defined transverse to the longitudinal axis124. The diameter136can vary along the length of the shaft104, e.g., larger toward the mounting end112and smaller toward the sharp inferior edge108. The diameter136can be selected to be patient specific, enabling the hollow shaft104to fill the shaft of the humerus12to a degree that provides advantageous filling of the humerus12. The diameter136can be constant along the length132. The diameter136can be varying along the length132. For example, the diameter136can increase along the longitudinal axis124between the sharp inferior edge108and the base133of the mounting end112. In some embodiments, the diameter136can progressively increase from the sharp inferior edge108of the hollow shaft104to the base133of the mounting end112.

The humeral stem100can have other lengths that are patient specific. For example, a length including the length132and a length of the mounting end112can be provided that is patient specific. The distance from the base133to the superior plane of the mounting end112on the medial side of the head10can be patient specific. The combination of the length132and the distance from the base133to the superior plane of the mounting end112on the medial side of the head10can be patient specific.

In some embodiments, the hollow shaft104is not circular or is not uniformly circular in cross-sections transverse to the longitudinal axis124along the length132of the hollow shaft104. For example, in one embodiment an inferior portion disposed away from the mounting end112can have a flattened portion134. The flattened portion134causes the hollow shaft104to extend outwardly to a lesser extent in the area of the flattened portion134. The lesser extent of the flattened portion134can enable the hollow shaft104to be less close to the exterior surface of the humerus12at the location where the flattened portion134is placed. The flattened portion134can be provided in a specific region for a patient where the specific patient's humerus12is narrower transverse to the longitudinal axis of the humerus12. The flattened portion134can be seen in transverse cross-section were a portion of the outer periphery of the hollow shaft104can be seen to have a circular portion in one region and an adjusted zone adjacent to the circular portion. The adjusted zone can have a non-circular periphery away from the circular portion. The adjusted zone can have a second circular periphery away from the circular portion, the second circular periphery being of a larger radius of curvature to provide a shallower area in the flattened portion134.

Another aspect in which the humeral stem100can be made patient specific is in the mounting end112. For example, the mounting end112can have a metaphyseal shape140that is patient specific. The metaphyseal shape140can be made patient specific with reference to 3D imaging, as discussed elsewhere herein. The metaphyseal shape140can have a patient specific metaphyseal volume with reference to 3D imaging. The metaphyseal shape140can include a radius of curvature of the base133. The metaphyseal shape140can include a depth between the inferior plane of the mounting end112and the apex of the base133at a boundary with the hollow shaft104. Other aspects of the configurations of the mounting end112and of the hollow shaft104that can be made patient specific are discussed below in connection with Section III.

1. Bone Integration Features

The stem embodiments disclosed herein can have various bone integration features formed therein or thereon.FIG.7Ashows that in one embodiment a humeral stem100A includes a bone integration feature182. The humeral stem100A is similar to the humeral stem100except as described differently below. The humeral stem100A can include a hollow shaft104A that is similar to the hollow shaft104but that has the bone integration feature182formed therein. The bone integration feature182can include a plurality of apertures184. The apertures of the plurality of apertures184can be arranged in any suitable manner. In one embodiment, the plurality of apertures184includes apertures that each have an inferior portion186, a superior portion188, and a space189disposed therethrough between the inferior portion186and the superior portion188. The apertures of the plurality of apertures184can be generally aligned the longitudinal axis124of the humeral stem100A. For example, the superior portion188of one of the apertures184can be superior of and medial of the inferior portion186of the aperture. The apertures of the plurality of apertures184can each be angled relative to a longitudinal axis of the hollow shaft104A. The apertures of the plurality of apertures184can each be aligned to a normal to the mounting end112. An angle between the aperture of the plurality of apertures184and a normal to the mounting end112can be less than an angle between the aperture and a longitudinal axis of the hollow shaft104. The apertures can have a tapered end190, e.g., at the superior portion188of the aperture. In other embodiments, the apertures can have a tapered end at the inferior portion186of the aperture. Both ends of the apertures of the plurality of apertures184can be tapered or non-tapered in other embodiments.

In use the humeral stem100A is implanted in cancellous bone of the humerus12distal a resection plane290. When so implanted, bone tissue can grow across the space189in the apertures of the plurality of apertures184. Such bone growth can create a bridge of bone from outside the hollow shaft104to the open area170disposed within the hollow shaft104A. In the illustrated embodiment, the bridged bone is concentrated in, e.g., entirely within a central zone of the hollow shaft104A. The apertures of the plurality of apertures184can be focused in, e.g., only in, the zone between the flattened portion134and the base133of the mounting end112. The plurality of apertures184can extend through the inferior wall168. The plurality of apertures184can extend through a superior portion of the inferior wall168. The plurality of apertures184can extend through an inferior portion of the inferior wall168, e.g., through a zone including the flattened portion134.

Although shown as being on the anterior side of the hollow shaft104A the plurality of apertures184can include apertures formed on posterior side. The plurality of apertures184can include apertures formed on the anterior and posterior sides. The plurality of apertures184can include apertures formed on the medial side. The plurality of apertures184can include apertures formed on the lateral side. The plurality of apertures184can include apertures formed on the medial and lateral sides. The plurality of apertures184can include apertures formed at intervals around the entire outer surface of the inferior wall168in at least one zone, e.g., in a superior portion of the inferior wall168disposed between the flattened portion134and the base133of the mounting end112, in the inferior wall168inferior of the base133of the mounting end112, in an inferior portion of the inferior wall168including being disposed through the flattened portion134.

Other structures can be provided for enhancing bone integration within the cancellous bone inferior of a resection plane. For example, the exterior surface of the inferior wall168can have a rough surface finish or a coating that enhances or hastens bone ingrowth. The interior surface of the inferior wall168can have a rough surface finish or a coating that enhances or hastens bone ingrowth. The exterior surface and the interior surface of the inferior wall168can have a rough surface finish or a coating that enhances or hastens bone ingrowth.

B. Articular Component Retention Configurations

Various advantageous component retention configurations are provided in various embodiments.FIG.8shows an example of a connection between a reverse articular body250and the mounting end112of one variant of the humeral stem100. The mounting end112includes a peripheral wall152that surrounds a space provided in the humeral stem100. The peripheral wall152enables an annular projection254of the reverse articular body250to be inserted into the mounting end112. The insertion of the annular projection254into the mounting end112can be along the direction of the arrow157.FIG.9shows that in some embodiments further insertion of the annular projection254through the peripheral wall152causes the inferior end of the annular projection254to engage one or more flexible flanges162of a locking mechanism160at the mounting end112of the humeral stem100. Following engagement, continued movement along the direction of the arrow157causes the flexible flanges162to move. For example, the flexible flanges162can include a first end164that is coupled with the peripheral wall152and a second end166. The second end166is spaced away from the first end164. The second end166is a free end. The second end166is disposed in a space or an open area170surrounded by the peripheral wall152and located away from the peripheral wall152.

The second end166can have a wedge shape. The second end166can include an inner edge166A and an outer edge166B. A thickness defined between the inner edge166A and the outer edge166B can vary along the length of the flexible flanges162between the first end164and the second end166. The thickness defined between the inner edge166A and the outer edge166B can increase between the first end164and the second end166. The thickness defined between the inner edge166A and the outer edge166B can increase to the second end166from a location between the second end166and the flexible flanges162. In one embodiment, the thickness defined between the inner edge166A and the outer edge166B increases by a first amount in a superior zone and by a second amount in an inferior zone. The first amount can be less than the second amount in various embodiments.

FIG.10shows that the locking mechanism160actuates to a locked configuration upon final advancement of the annular projection254into the space or open area170surrounded by the peripheral wall152. Upon full insertion of the annular projection254the flexible flanges162deflect into the open area170and away from the peripheral wall152. Deflection of the flexible flanges162away from the peripheral wall152preferably results in a locking engagement between the annular projection254and the flexible flanges162. The locking engagement can be provided between an inferior edge of the second end166and a superior facing taper262of the annular projection254. The flexible flanges162can deflect away from the peripheral wall152until the inferior edge of the second end166is disposed over, e.g., facing or in some cases contacting the superior facing taper262. If the inferior edge of the second end166is not touching the superior facing taper262the inferior edge is generally disposed directly above the superior facing taper262such that movement the opposite direction of the arrow157induces such contact which opposes and prevent further movement in the direction opposite the direction of the arrow157.

FIG.11shows a model of the operation of the locking mechanism160. A single one of the flexible flanges162is shown with the second end166thereof in contact with the superior facing taper262of a model of the annular projection254of a reverse articular body250. An arrow267indicated a load being applied in a direction away from the humeral stem100, e.g., superiorly. The first end164is shown in the analysis affixed to a ground surface, which is the peripheral wall152. This is because the flexible flanges162are coupled with the mounting end112and are relatively inflexible in compressive loading. The relative inflexibility of the flexible flanges162causes force from the load along the arrow267to be opposed by an opposing force Fc from the peripheral wall152from which the flexible flanges162extend. The opposing force from the peripheral wall152is applied from the second end166to the superior facing taper262. The opposing force Fc applied to the taper262and a friction force F1are directed inferiorly and combine to a resultant force FR directed inferiorly.FIG.11shows that the inferiorly directed forces can be applied symmetrically on opposite sides of the annular projection254. These forces can be applied all around the projection254. These inferiorly directed forces counteract that force along the arrow267and as resolved result in great security to retain the articular body250.

FIGS.12-15show different combinations of the humeral stem100and various articular bodies.FIG.12show an anatomic articular body200coupled with the humeral stem100. The anatomic articular body200includes a tapered projection204that is configured to mate with the inside surface122adisposed about the mounting hole116. The tapered projection204has a tapered profile that create an interference fit, e.g., a Morse taper, with a tapered profile of the inside surface122a.

For certain patients there is a need to convert the anatomic assembly ofFIG.12to a reverse assembly ofFIG.2. The anatomic articular body200can be removed by a convention technique such as by prying the anatomic articular body200off of the inner wall122of the humeral stem100. After the mounting end112has been exposed by removing the anatomic articular body200, a reverse articular body250illustrated inFIGS.14and15can be coupled with the mounting end112of the humeral stem100. The reverse articular body250can include an annular projection254which is shown schematically inFIGS.8-10. The annular projection254surrounds a space256formed in the reverse articular body250. The space256is configured to receive the inner wall122when the reverse articular body250is coupled with the locking mechanism160. The annular projection254includes an inferior facing taper258. The inferior facing taper258is configured to engage the flexible flanges162to deflect the flexible flanges162away from the inner wall122and toward the outer wall121. The reverse articular body250includes a superior body264that is disposed superiorly of the annular projection254. The superior body264, on one side, encloses the superior end of the space256. The superior body264, on the opposite side provides an articular surface266to engage a glenosphere in a reverse shoulder assembly.

C. Method of Implanting Stem With Patient Specific Metaphysis

FIGS.16-18show steps that can be performed in a method of implanting a humeral stem, e.g., a patient specific variation of the humeral stem100. Prior to the steps illustrated inFIGS.16-18the humerus12can be resected in a convention manner. In some cases, the humerus12can be resected using a patient specific guide to cause the resection plane290to be in a specific location along the length of the humerus12. Another aspect of these methods that can be patient specific is the preparation of the humerus12to receive the humeral stem100.

FIG.16shows a reamer head328that can be coupled with a reamer shaft300in a process for forming the bone inferior of the resection plane290. The reamer head328can be made patient specific to form a concave recess in the humerus12inferior of the resection plane290. For example 3D imaging of the humerus12can be obtained. An appropriate configuration of the humeral stem100can be determined based upon the 3D imaging. For example, the metaphyseal shape140can be determined based on an analysis of the shape, volume, and bone quality of the humerus12. In one example the metaphyseal shape140can include an outer, inferior surface of the mounting end112. The outer, inferior surface of the metaphyseal shape140can be at least partially spherical.

A spherical surface of the metaphyseal shape140of the humeral stem100can be mirrored in the reamer head328. For example, the reamer head328can include an outer surface, e.g., an exterior reaming surface332, configured for reaming the cancellous bone inferior of the resection plane290of the humerus12. The reamer head328can have a patient specific feature336, in one embodiment the reamer head328can have a patient specific curvature340. The radius of curvature of the reamer head328can match a desired radius of curvature of a patient specific recess360. The reamer head328includes an aperture through which a first end304of the reamer shaft300can be inserted.FIG.16shows that the first end304can be inserted into the reamer head328and through the channel as indicated by the arrow344. Thereafter the reamer head328can be secured to the first end304. The reamer head328can be secured to the first end304such that the reamer head328can be rotated by the reamer shaft300. In some methods, a second end308of an elongate body312of the reamer shaft300can be secured to a driver configured to rotate the elongate body312and to thereby rotate the reamer head328. Such rotation can be performed while at the same time advancing the reamer shaft300and the reamer head328along the direction indicted by the arrow348. Further advancement of the reamer shaft300and the reamer head328along the arrow348causes the cancellous bone to be removed. As a result a patient specific recess360is formed in the resection plane290of the humerus12.

In one method the humeral stem100can be advanced into the humerus12at the resection plane290. The humeral stem100can be advanced by securing a stem holder380to the humeral stem100. The stem holder380can include a first end384and a second end388. The first end384can be configured to mate with a portion of the mounting end112. The first end384has a stem interface398D configured to secure to the mounting end112of the humeral stem100. The second end388can have a surgeon interface such as a handle that can be actuated to grasp and, later, release the grasp of the mounting end112of the humeral stem100. The stem holder380includes an elongate body392enabling the surgeon to hold the humeral stem100remotely of the joint space and remotely of the humerus12.

In one method, the stem holder380is advanced as indicated by the arrow394to position the first end384in the mounting end112. The second end388can be actuated to engage a coupler398A including the stem interface398D if the coupler is removable from the stem holder380. The stem holder380can have a stem interface398D at the first end384for connection to the mounting end112of the humeral stem100. The second end388can be manipulated to move the elongate body392and the humeral stem100as indicated by the arrow396to move the humeral stem100into the humerus12. As indicted by the head of the arrow346the humeral stem100can be directed into the humerus12along a longitudinal axis of the humerus12.FIG.18shows that the bone inferior of the patient specific recess360can be un-prepared. In other words, contrary to common practice further steps of preparing the interior of the humerus12inferior of the reamed area are not needed. For example, even though the humeral stem100includes the hollow shaft104the humeral stem100does not require a connection be made to the intramedullary canal of the humerus12.

Rather, the sharp inferior edge108of the humeral stem100is configured to create access as it is being advanced into the cancellous bone. The sharp inferior edge108cuts a pathway for the humeral stem100into the interior of the humerus12.

FIGS.18-18Cshow various aspects of embodiments of the stem holder380and the coupler398A, which can be removable.FIG.18Cshows that removable coupler398A includes a superior end398B that is configured to be coupled with the stem holder380. The superior end398B can include a tooling interface398C. In one embodiment, the tooling interface398C includes two apertures that are oriented away from each other. The stem holder380can have at the first end384prongs corresponding to the apertures. The prongs can be actuated to move into and out of engagement with the apertures in the tooling interface398C of the removable coupler398A.

FIG.18Ashows that the removable coupler398A can have an annular projection398E as part of the tooling interface398C. The annular projection398E can include an outer surface398F and an inner surface398G. The outer surface398F can be configured to be received into the mounting end112such that the outer surface398F is disposed within superior portions of the flexible flanges162by advancing the stem holder380as indicated by the arrow394(seeFIG.18). The outer surface398F can be sized such that the diameter or width of the outer surface398F is larger than the undeflected configuration of the flexible flanges162(e.g., as shown inFIG.8). The outer surface398F can be sized to deflect the flexible flanges162when received therein to the configuration shown inFIG.9. The outer surface398F preferably lacks a structure similar to the superior facing taper262in the annular projection254(SeeFIG.10) such that the removable coupler398A is not trapped inferior to the inferior edge of the flexible flanges162. The outer surface398F is sized such that when received in the flexible flanges162with the flexible flanges162in the deflected state friction between the flexible flanges162and the outer surface398F securely holds the humeral stem100to the removable coupler398A but does not prevent removal of the removable coupler398A from the mounting end112of the humeral stem100.

The inner surface398G of the removable coupler398A is sized to receive or not interfere with the inner wall122. When the annular projection398E is advanced into the mounting end112the annular projection398E is disposed between the outer wall121and the inner wall122. Thus the width of the annular projection398E is less than the distance between the radially inward facing surface of the outer wall121and the radially outward facing surface of the inner wall122. As noted above, the coupler398A can be removable such that the stem holder380can be used with other types of stem or stemless humeral anchors. The coupler398A can in other embodiments be part of the first end384of the stem holder380and not removeable from the inferior portions of the stem holder380.

Although the humeral stem100can be patient specific, e.g., comprising a patient specific metaphyseal shape140, the interior surface of the mounting end112can be generic. Accordingly, the coupler398A can be generic to many or all patients. For example, even if the size and/or the shape of the humeral stem100, e.g., the metaphyseal shape140, is made patient specific, the size and/or the shape of the annular projection398E can be the same for some or all humeral stems100. The outer surface398F can have a diameter that matches an inner diameter of the humeral stem100, which can be generic to all patients even as portions of the humeral stem100to be disposed beneath the resection plane290are made patient specific.

The foregoing apparatuses, systems, and methods together enable placement of the humeral stem100in the humerus12with minimal tools and steps. Also, due to the patient specific nature of one or more aspects of the humeral stem100the stem provides excellent fit in the humerus12even under the streamlined process described above.

D. Patient Specific Shoulder Joint Implantation Kit

FIG.19shows a kit400that includes various inventive components combined in inventive ways. The kit400includes a surgical kit404and a patient kit408in one embodiment. The surgical kit404can be used for more than one patient. The surgical kit404can include, among other components the reamer shaft300and the stem holder380. These components of the surgical kit404can be configured for refurbishment and re-use.

The patient kit408can be a patient specific kit. The patient kit408can include the humeral stem100which can be made patient specific in one more aspects. The patient kit408can also include the reamer head328. The reamer head328can be made patient specific in one or more aspects. For examples,

Current surgical techniques for shoulder articulation replacement include several successive steps including reaming the humeral head, making an entry into the bone, preparing the bone including punching, compacting, fixing an implant, protecting the implant, making a trial articulation mounting and mounting the final implant. This results in a longer and more costly procedure than necessary. Moreover, the known techniques which use patient specific implants or ranges of implants also need patient specific or ancillary tools such as rasps, drills and cutting guides, whose manufacturing and shipping is costly.

A goal of the invention is to provide a new surgical method for shoulder articulation replacement which is more simple, and less costly than the techniques of the prior art.

III. Patient Specific Reverse Shoulder Implant

The foregoing embodiments can be made patient specific in some cases. Patient specific shoulder implants can improve the performance and the longevity of a shoulder replacement. In some cases, it is desirable to provide a reverse shoulder assembly that is not only patient specific in a single aspect but can be made specific and appropriate for a specific patient in a number of relevant aspect. Section III(A) discusses various methods for providing a patient specific reverse should joint humeral implant. Section III(B) discusses various examples of features of reverse should joint humeral implants that can be arranged in a patient specific manner. These sections are relevant to the humeral implants disclosed herein above and claimed herein.

A. Method of Providing Manufacturing Reverse Shoulder Assemblies

FIG.20shows a method500of providing a humeral implant. The method500can be directed to providing a reverse shoulder humeral implant. The reverse shoulder humeral implant can be similar to those discussed above, e.g., to the humeral implant90which includes the hollow humeral stem100. The method500can be used to form a solid humeral anchor or stem as discussed below. The method500can be used to form other anchors. stems, articular bodies and other shoulder assembly components as well.

In an early portion of one embodiment of the method500, a step504is performed in which glenohumeral joint information of a specific patient is obtained. Glenohumeral joint information can be obtained by any imaging modality, such as MRI, CT scan, Xray or other imaging techniques. Glenohumeral joint information can include a wide range of information, such as the size, shape and form of the humerus, the size, shape and form of the glenoid. Glenohumeral joint information can include the relative positions of portions of the humerus (e.g., the greater trochanter, the lesser trochanter, or other prominent landmarks), of portions of the scapula (e.g., the glenoid, the acromion, or other prominent landmarks), and of portions of other bone portions around the shoulder.

Glenohumeral joint information can include range of motion analysis.FIG.20Ashows an example of various forms of range of motion analysis that can be included in the step504. For example, the patient can be instructed to move an arm of an affected shoulder joint to provide shoulder extension. The amount of extension, e.g., the angle between the arm and the medial-lateral-vertical plane of the body, can be determined. The patient can be instructed to move an arm of an affected shoulder joint to provide shoulder abduction and/or adduction. The amount of abduction, e.g., the angle between the arm and the anterior-posterior-vertical plane of the body, can be determined. The patient can be instructed to move an arm of an affected shoulder joint to provide shoulder flexion. The amount of flexion, e.g., the angle between the arm and the medial-lateral-vertical plane of the body, can be determined. The patient can be instructed to move an arm of an affected shoulder joint to provide shoulder internal or external rotation. The amount of internal or external rotation, e.g., the angle swept by the hand moving from a neutral position internally or from a neutral position externally can be determined. The patient can be instructed to move an arm of an affected shoulder joint to provide shoulder horizontal rotation. The amount of horizontal rotation, e.g., the angle swept by the hand moving upward or downward from a laterally extended horizontal position can be determined.FIG.20Aillustrates just some aspects of range of motion analysis that can be included in the step504. For example, range of motion analysis can also be performed at least partially virtually to determine a desired range of motion based on the glenohumeral joint information (e.g., in step512described below). A virtual analysis can be performed iteratively with obtaining glenohumeral joint information in step504.

Glenohumeral joint information can include interactions among, e.g., impingements between, the bones, among components coupled with the bones, or among a component coupled with one bone and a bone portion opposite the component following implantation.

Glenohumeral joint information can include an analysis of tension in soft tissues. For example, the humerus and the scapula are held in adjacency by soft tissues, e.g., muscles, tendons, ligaments and other soft tissues.

The method500can proceed to a step508in which an initial manufacturing plan is provided. The initial manufacturing plan can be based on a subset of glenohumeral joint information. For example, the step508can provide a manufacturing plan that sets the general size and shape of a component of the humeral implant90or another humeral implant. The step508can provide a manufacturing plan that sets the general size and shape of the humeral stem100or of a solid humeral anchor as discussed below in connection withFIGS.21-29. The step508can involve providing an initial manufacturing plan to a surgeon preforming a pre-operative analysis of the patient to assess the proper shoulder implant arrangement. The step508can involve providing an initial manufacturing plan to a display for a user to evaluate the initial manufacturing plan.

FIG.20Bshows an example of some of the analyses that can be conducted to provide an initial manufacturing plan according to the step508. The size of a humerus12can be determined as a width transverse to a central longitudinal axis LA of the humerus12and a size of a humeral anchor550can be determined accordingly. In one embodiment the step508determines a first width W1with reference to a second width W2. The second width W2can be the width of the humerus12in a metaphysis portion of the humerus. The Second width W2can be found at a location superior to the neck of the humerus12. The second width W2can be measured form one edge of a resection plane of the humerus12to an opposite lateral cortical surface of the humerus12. The first width W1can be chosen in the initial manufacturing plan according to step508to not exceed a metaphysis filling ratio FRmetwhich can be calculated as the ratio of first width W1to second width W2as shown. Preferably the metaphysis filling ratio FRmetdoes not exceed 0.95 in some embodiments, does not exceed 0.9 in some embodiments does not exceed 0.85 in some embodiments, does not exceed 0.8 in some embodiments, does not exceed 0.75 in some embodiments, does not exceed 0.7 in some embodiments. The metaphysis filling ratio FRmetpreferably is in a range of 0.5 to 0.95 in some examples. The metaphysis filling ratio FRmetpreferably is in a range of 0.6 to 0.9 in some examples. The metaphysis filling ratio FRmetpreferably is in a range of 0.7 to 0.85 in some examples.

The size of a diaphysis portion of the humeral anchor550can also be specified in an initial manufacturing plan during the step508. A third width W3can be defined in the diaphysis region of the humeral anchor550. The third width W3can be measured transverse to a longitudinal axis of the humeral anchor550at a location spaced form the inferior end o the humeral anchor550. The third width W3can be initially selected during the step508as part of the initial manufacturing plan as a function of the bone of the humerus12. For example, the diaphysis portion of the humerus12can have a fourth width W4transverse to the central longitudinal axis LA of the humerus12. The fourth width W4can be measured at a location where the portion of the humeral anchor550intended to come to rest at the location of the measurement of the fourth width W4is the portion having the third width W3. A diaphysis filling ratio FRdiacan be defined as a ratio of the third width W3to the fourth width W4. The third width W3can be chosen in the initial manufacturing plan according to step508to not exceed a selected diaphysis filling ratio FRdiaPreferably the diaphysis filling ratio FRdiadoes not exceed 0.95 in some embodiments, does not exceed 0.9 in some embodiments does not exceed 0.85 in some embodiments, does not exceed 0.8 in some embodiments, does not exceed 0.75 in some embodiments, does not exceed 0.7 in some embodiments. The diaphysis filling ratio FRdiapreferably is in a range of 0.5 to 0.95 in some examples. The diaphysis filling ratio FRdiapreferably is in a range of 0.6 to 0.9 in some examples. The diaphysis filling ratio FRdiapreferably is in a range of 0.7 to 0.85 in some examples.

Other aspects of size and form can also be determined for at least one component of a humeral implant, such as the humeral implant90.FIG.20Bshows that the humeral anchor550can be shaped to have an angular or an arcuate form. The superior portion can be disposed more medially than the inferior portion thereof when applied to the humerus12. The outer surfaces can be curved. One measure of the degree of curvature of the humeral anchor550is an angle α as measured between the central longitudinal axis LA and a line L1connecting a center of an inferior tip of the humeral anchor550and the geometric center C of a superior face of the humeral anchor550. The greater the angle α the more medially spaced the superior face is from the inferior tip. The greater the angle α the closer the superior face of the humeral anchor550is to the cortical bone at the resection surface of the humerus12. By minimizing exposed cancellous bone at the medial calcar the humeral anchor550can reduce, minimize or eliminate the chance for stress shielding at the medical calcar.

FIG.20Cshows other aspects of the method500. The bones of an affected shoulder joint of a specific patient can be evaluated as part of obtaining glenohumeral joint information in the step504to determine how close the humerus12(or some portion thereof) is to the scapula14(or some portion thereof). For example a bone spacing S1can be determined between the greater tuberosity22of the humerus12and the acromion20of the scapula14. The bone spacing S1gives a sense for the condition of the soft tissue tensioning the shoulder joint. This is just one example of a metric that can be used to assess the bones from preoperative imaging.FIG.20Ccan also inform the step508. Specifically, it may be determined that the bone spacing S1suggests that to achieve improved soft tissue tensioning the humeral anchor550should be able to put more tension on the soft tissue given an anticipated location of a glenosphere in the bone. Then, the imaging illustrated inFIG.20Ccan automatically or by the surgeon's selection begin the method500with a humeral anchor550having a greater thickness metaphysis portion, as discussed further below.

The step508can involve providing an initial manufacturing plan to software able to create a virtual model of a specific patient's shoulder based on the step504of obtaining glenohumeral joint information.FIG.20Dshows an example of a virtual model. The model can include models of the humerus12and the scapula14and relevant portions thereof such as the greater tuberosity22and the acromion20. Virtual components such as a virtual humeral anchor550V can be constructed in the model to enable the method500to generate an initial and/or a final manufacturing plan. The manufacturing plan can take into account the bone spacing S2that is desired as between relevant bone segments as a metric for suitable soft tissue tensions. The manufacturing plan can take into account the spacing S2that is desired as between a bone segment and a component of shoulder implant to reduce, minimize or eliminate bone impingements that could lead to notching.

FIG.20shows that a step512involves performing a virtual glenohumeral joint biomechanical analysis. Software can modify one or all of a variety of parameters discussed below in connection withFIGS.21-31and more. The step512can confirm that the initial manufacturing plan provided in the step508is appropriate for a specific patient. An arrow516shows that if the initial manufacturing plan is confirmed one or more steps of the method500can be skipped. The arrow516shows that a step528can directly follow the step512in some embodiments, where the initial manufacturing plan provided in the step508is confirmed in the step528.

In some variations and for some patients, the initial manufacturing plan provided in step508is not appropriate for the specific patient. As a result the method500involves modifying a humeral joint implant characteristic in a step520. The step520can be followed as indicated by arrow524by repeating the step512in which virtual glenohumeral joint biomechanical analysis is performed on a manufacturing plan as modified from the initial manufacturing plan according to the step520.

The step512can be performed in the same way in connection with the first modification of the initial manufacturing plan provided in the step508as provided in the step520. In some cases the second instance of the step512following the modification of the initial manufacturing plan provided in step508is different potentially focusing on the aspect(s) that was or were modified.

The modification provided in the step520and the virtual analysis conducted in step512can be iterated as many times as beneficial for providing a well configured humeral implant.

An instance of the step512following the modification of the initial manufacturing plan concludes that a well configured virtual humeral implant has been identified. As a result the arrow516shows that the method500can follow to a step528in which a final manufacturing plan is confirmed. The final manufacturing plan provided in the step528can be provided in written or electronic form to enable humeral implant components to be made. The method500can follow to a step532in which one or more patient specific components can be manufactured.

During or after any step of the method500, the method can include a step of outputting an indication to the user that a parameter that is selected or modified is selected or modified to provide a specific performance benefit, e.g., prior to or after the step532.

As discussed further below the method500can be used to cause a humeral anchor, e.g., with a stem, or an articular body to be manufactured for a specific patient that is well configured for one or a number of characteristics of humeral joint implants.

B. Patient Specific Humeral Anchor Structures

As noted above, methods are disclosed herein for creating patient specific shoulder implants and components. The method can be used to create unique humeral anchor structures for specific patients in many different aspects.

1. Humeral Anchors with Patient Specific Inclination Angle Adjustments

FIG.21shows a humeral anchor550that can be applied to a patient at a superior humeral resection plane. The method500includes a stem portion554and a metaphysis portion558. The stem portion554is located inferior of the metaphysis portion558when the humeral anchor550is applied to a humerus. The stem portion554comprises a generally slender member that can be sized as described above according to an analysis of the diaphysis portion of a humerus of a specific patient. The stem portion554can extend along a primary stem axis562. The metaphysis portion558also can be similarly sized. As discussed in connection with the humeral stem100the metaphysis portion558can have a metaphyseal shape that is well suited for the metaphysis of the specific patient humerus. The metaphysis portion558can be oriented medially with a superior face extending transverse to a metaphyseal axis566. An initial inclination angle570can be defined in at least two ways. The initial inclination angle570can be measured between a horizontal axis and an axis572dispose in the plane of the superior face of the metaphysis portion558. The initial inclination angle570can also be defined as the angle between the primary stem axis562and the metaphyseal axis566. In other case, the method500can proceed by defining the initial inclination angle570in the step508. In one embodiment the initial inclination angle570is between 140 and 150 degrees, e.g., 145 degrees. The humeral anchor550can be defined to have the initial inclination angle according to the step508where a surgeon or a virtual analysis identifies the specific patient as benefiting from an initial reverse shoulder procedure. The step512, the step520, and the step520of the method500can modify the inclination angle upward or downward from this starting point for such patients. A surgeon or user of the method may modify the initial inclination angle to higher inclination angles to provide more stability of the implant in the humerus and less humeral lateralization. In some cases this is preferred even though taken alone the higher inclination angles may correspond to a higher risk of scapular notching. As discussed herein, scapular notching can arise from an articular body insert wearing on the scapula. The higher risk of notching arising from higher inclination angles can be countered by any of the other features herein that reduce notching risk, e.g., jump distance configurations. Lower inclination angles, e.g., reduced from an initial angle of 145 degrees in the step520can provide more humeral lateralization. Lower inclination angles can reduce the risk of scapular notching. Lower inclination angles may provide less stability, this potentially lower stability can be addressed by enhancing the humeral head filling configurations.

FIG.21shows that a humeral anchor550A can be provided that has a reduced inclination angle574. The reduced inclination angle574is reduced compared to the initial inclination angle570. The reduced inclination angle574can correspond to a larger angle α as discussed above in connection withFIG.20B. The reduced inclination angle574can be between 120 and 140 degrees, e.g., about 132.5 degrees. The humeral anchor550A can be configured with these the initial inclination angle according to the step508where a surgeon or a virtual analysis identifies the specific patient as potentially needing a reverse shoulder revision procedure in the future, following an initial anatomic shoulder implant. The step512, the step520, and the step528of the method500can modify the inclination angle from this starting point and confirm the final manufacturing plan for such patients.

FIG.21also shows a humeral anchor550B that includes an increased inclination angle578. The increased inclination angle578is greater than that of the humeral anchor550. The increased inclination angle578can be between 150 and 160 degrees, e.g., can be 155 degrees. The increased inclination angle578can correspond to a lesser angle α as discussed above in connection withFIG.20B.

As discussed above, a wide range of flexibility can be provided form a plurality of starting points which can enable much improved fit for a specific patient based on pre-operative imaging. The result takes into account the specific patient's needs with regard to inclination angle and the specific patient anatomy, expedites the process by selecting among categories of patients such as leaving open the possibly of converting from anatomic to reverse or knowing that such conversion is not going to be useful. The result also simplifies the procedure by allowing the humeral anchor produced by the method500to have an inclination angle that well matches the humerus such that less resection and subsequent bone modification, e.g., reaming, is needed.

2. Humeral Anchors with Patient Specific Center of Rotation Offset Adjustment

FIG.22shows that for some patients the humeral anchor550can be adapted to be patient specific with regard to the center of offset of the center of rotation. The humeral anchor550can include the stem portion554and the metaphysis portion558. The metaphysis portion558can be coupled with an articular body559. The stem portion554can extend along the primary stem axis562as discussed above.

The humeral anchor550can be configured such that the center of rotation of the articular body559can be aligned in the posterior-anterior direction with the primary stem axis562. In one embodiment, the metaphysis portion558can be configured with respect to the stem portion554such that the geometric center of the metaphysis portion558is aligned in the posterior-anterior direction with the primary stem axis562. The method500can be used, e.g., in the step520, to modify the humeral anchor to adjust the center of rotation of the articular body559relative to the stem portion554.FIG.22shows that a posterior center of rotation offset590can be provided between the stem portion554and the metaphysis portion558. The posterior center of rotation offset590provides that the center of rotation of the articular body559(large cross) can be disposed in a posterior direction (to the right on the page) relative to the posterior-anterior direction relative to the posterior-anterior location (small cross) of primary stem axis562.

The posterior center of rotation offset590can be approximately 2 mm. The posterior center of rotation offset590can be approximately 4 mm. The posterior center of rotation offset590can be between 1 and 8 mm. The posterior center of rotation offset590can be between 2 and 6 mm.

FIG.23, in the right-most image, shows the center of rotation offset590can also be provided in an anterior direction between the center of rotation of the articular body559and the posterior-anterior location of primary stem axis562. An anterior offset of can be approximately 1 mm, can be approximately 2 mm, can be approximately 3 mm, can be approximately 4 mm in some embodiments. The anterior center of rotation offset590can be between 1 and 5 mm inclusive. The anterior center of rotation offset590can be between 2 and 4 mm inclusive.

FIG.23also shows that a medial center of rotation offset594can be provided that can be adjusted in a patient specific manner as well. The center of rotation of the articular body559can be off-set in a medial direction relative to the primary stem axis562by a first amount (left-most image) and can be off-set in a medial direction relative to the primary stem axis562by a second amount (third-from left image). The first amount can be within a range of 18-26 mm inclusive, or can be within a range of 19-25 mm inclusive, or can be within a range of 20-24 mm inclusive. The first amount can be about 22 mm. The second amount can be within a range of 10-19 mm inclusive, or can be within a range of 12-18 mm inclusive, or can be within a range of scapula 14-17 mm inclusive. The second amount can be about 17 mm.

Providing a patient specific posterior or anterior offset of the center of rotation of the articular body559relative to the primary stem axis562or another part of the stem portion554can advantageously allow the surgeon to better fit the humeral anchor to the specific patient's shoulder. Additional benefits of patient specific posterior-anterior offset adjustment can reduce, minimize or eliminate impingement risk and/or dislocation risk and can optimize range of motion, stability, and soft-tissue tensioning.

3. Humeral Anchors with Patient Specific Patient Specific Version Adjustment

FIG.24show another aspect in which the method500can confirm a manufacturing plan, potentially following a modification of an initial manufacturing plan wherein a patient specific version is provided. The humeral anchor550includes an initial version angle604as defined between the stem portion554and the metaphysis portion558. As with other initial settings of the various parameters described herein the initial version angle604can be selected as a center of a distribution of suitable version settings for an expected population. In one approach the initial version angle604is selected as a neutral setting. This assumes that when the humerus is in a neutral position a scapula side articular surface (e.g., on a glenosphere) with which the articular body interacts will be entered on the articular body.

If the scapula side articular surface is angled anteriorly the initial version angle604can be adjusted in the step520. For example a humeral anchor550E can be provided in which a first version offset608is provided. The first version offset608is offset from the initial version angle604. The first version offset608is well suited to a scapula side articular surface that is oriented anteriorly. For such a scapula side articular surface the first version offset608allows the center of the articular body559to be centered on the center of the scapula side articular surface. This allows for approximately equal amounts of motion in anterior and posterior directions for example. The first version offset608can be between 5 and 50 degrees inclusive, can be between 10 and 45 degrees inclusive, can be between 15 and 40 degrees inclusive, can be between 20 and 35 degrees inclusive, can be approximately 25 degrees in some embodiments. Arriving at a selected first version offset608for a specific patient can be through the iterative method500, e.g., incrementally increasing the first version offset608until a patient specific arrangement is selected.

If the scapula side articular surface is angled posteriorly the initial version angle604can be adjusted in the step520. For example a humeral anchor550F can be provided in which a second version offset612is provided. The second version offset612can be measured in the same direction as the first version offset608, for example a counter-clockwise angle from 12 o'clock. The second version offset612is offset form the initial version angle604. The second version offset612is well suited for a scapula side articular surface that is oriented posteriorly. For such a scapula side articular surface the second version offset612allows the center of the articular body559to be centered on the center of the scapula side articular surface. This allows for approximately equal amounts of motion in anterior and posterior directions for example. The second version offset612can be between reamer shaft300and 355 degrees inclusive, can be between 320 and arrow 355 degrees inclusive, can be between 340 and 355 degrees inclusive, can be approximately 350 degrees in some embodiments. Arriving at a selected second version offset612for a specific patient can be through the iterative method500, e.g., incrementally increasing the first version offset608until a patient specific arrangement is selected.

Additional benefits of patient specific version adjustment can reduce, minimize or eliminate impingement risk and/or dislocation risk and can optimize range of motion and stability.

4. Humeral Implant with Patient Specific Metaphysis Portion Thickness

FIG.25show another aspect in which the method500can confirm a manufacturing plan, potentially following a modification of an initial manufacturing plan wherein a patient specific thickness of a humeral implant, e.g., a metaphyseal portion of a humeral anchor is provided. The humeral anchor550can have a metaphysis bowl thickness622that is initially selected and provided in the step508of the method500. The metaphysis bowl thickness622can be selected initially based upon a relevant population of patients. The metaphysis bowl thickness622can be based on an evaluation such as described in connection withFIG.20C.

FIG.25shows that a humeral implant length620is another parameter that can be made patient specific. In this context, humeral implant length620is defined as the superior-inferior distance from the inferior end556of the humeral anchor550to the initial center of rotation position586. In one variation of the method500the step520adjusts the thickness of the metaphysis bowl. Humeral anchor550G is an embodiment with a first modified metaphysis bowl thickness626. The first modified metaphysis bowl thickness626has a thickness that is less than the thickness of the humeral anchor550. The first modified metaphysis bowl thickness626corresponds to a first modified humeral implant length624, one that is less than the humeral implant length620of humeral anchor550.

In another embodiment, a humeral anchor550H is provided that can be manufactured following the method500. The humeral anchor550H can include a second modified metaphysis bowl thickness630that is greater than the humeral implant length620. The second modified metaphysis bowl thickness630can provide a second modified humeral implant length628.

The second modified humeral implant length628has the benefit of moving the center of rotation of the humerus to which the humeral anchor550H is a part to be moved further away from the mid-line of the patient. This can be useful in addressing a patient with lax soft tissue around the shoulder or with larger patients. The humeral anchor550G has the benefit of moving the center of rotation of the humerus to which the humeral anchor550G is a part to be moved toward the mid-line of the patient. This can be useful in addressing a patient with tight soft tissue around the shoulder or with smaller patients.

Additional benefits of patient specific humeral implant thickness can reduce, minimize or eliminate dislocation risk and optimize stability.

5. Humeral Anchors with Patient Specific Articular Body Lead Angle

FIG.26shows another aspect in which the method500can confirm a manufacturing plan, potentially following a modification of an initial manufacturing plan wherein a patient specific articular body lead angle is provided. In one embodiment the humeral anchor550is coupled with an articular body559. The articular body559has a lead angle642which can be the angle disposed between an outer peripheral surface of the articular body559and a superior side of the articular body559as shown. The lead angle642can be modified in the method500from an initial lead angle642to a modified lead angle646that is advantageous from the perspective of one or more aspects of performance. For example, in the step512of the method500a biomechanical analysis can include confirming whether the articular body559impinges on any bone during the course of movement. If there is bone impingement is likely as indicated in the step512, the method500can follow to the step520in which the lead angle can be modified. The lead angle can be decreased to reduce the likelihood of impingement, e.g., to the modified lead angle646.

In at least one method, the lead angle can initially be defined in the step508as a relatively smaller angle, e.g., similar to the angle modified lead angle646and can be increased following the step512in which a lack of impingement is confirmed. For some patients where impingement is less likely the method500can be shorter if starting with a larger initial lead angle in the step508. For some patients where impingement is more likely the method500can be shorter if starting with a smaller initial lead angle in the step508.

Additional benefits of patient specific articular boy lead angle can reduce, minimize or eliminate notching risk.

6. Humeral Anchors with Patient Specific Metaphysis Portion Width

FIG.27shows another aspect in which the method500can confirm a manufacturing plan, potentially following a modification of an initial manufacturing plan wherein a patient specific metaphyseal portion and/or articular body width is provided. The width of the metaphysis portion558and/or the width of the articular body559can be set as corresponding to a first metaphysis width662. The first metaphysis width662can be the same for the superior face of the humeral anchor550and for the superior edge of the articular body559. The first metaphysis width662can be initially defined in the step508. The initial width can be about 36 mm, and in some embodiments can be from 32-40 mm, in other embodiments between 28 and 44 mm.

In part of the method500the appropriateness of the width can be confirmed in the method500, such as in the step512. If a wider metaphysis portion558and/or a wider articular body559is deemed suitable, the step520can adjust the width upward. A humeral anchor550I can be provided with a second metaphysis width666that is wider than the first metaphysis width662. The second metaphysis width666can be about 42 mm in one embodiment. The second metaphysis width666can be in a range 38-46 mm or 32-50 mm in other embodiments.

To expedite the method500the initial width can be similar to the first metaphysis width662and then adjusted toward the second metaphysis width666or can initially be similar to the second metaphysis width666and adjusted to the first metaphysis width662. Also, a middle width can be initially selected and the method500be used to adjust the width upward or downward.

Providing a patient specific metaphyseal portion and/or articular body width can advantageously allow the surgeon to better fit the humeral anchor to the specific patient's shoulder.

7. Humeral Anchors with Patient Specific Articular Body Center of Rotation Offset

FIG.28shows another aspect in which the method500can confirm a manufacturing plan, potentially following a modification of an initial manufacturing plan wherein a patient specific articular body center of rotation offset is provided. For example, in one variant of the method500the articular body559is configured in the step508with a concave articular recess that is centered relative to, e.g., where a line connecting a center of rotation of the articular body559with the geometric center of the outer periphery of the superior face of the articular body559is normal to the superior face of the articular body559. Said another way, in the step508where the initial manufacturing plan is defined projection of the center of rotation onto the plane of the superior face of the articular body559intersects the geometric center of the superior face of the articular body559.

FIG.28shows an articular body559B that can result from the step512and step520, resulting in the center of rotation being offset from the geometric center of the articular body559B. In particular, a first center of rotation position682can be provided, wherein the center of rotation is offset from the geometric center. The first center of rotation position682is illustrated by a small cross on the face of the articular body559B. The geometric center is illustrated by a large cross on the face of the articular body559B. As can be seen, the small cross is disposed to the left and above the center of the large cross in the figure for the first center of rotation position682. The distance from the geometric center to the first center of rotation position682can be approximately 1 mm, can be approximately 2 mm, can be approximately 3 mm, can be approximately 4 mm in some embodiments. The distance from the geometric center to the first center of rotation position682can be between 1 and 5 mm inclusive. The distance from the geometric center to the first center of rotation position682can be between 2 and 4 mm inclusive.

FIG.28shows an articular body559C that can result from the step512and step520, resulting in the center of rotation being offset from the geometric center of the articular body559C. In particular, a second center of rotation position686can be provided, wherein the center of rotation is offset from the geometric center. The second center of rotation position686is illustrated by a small cross on the face of the articular body559C. The geometric center is illustrated by a large cross on the face of the articular body559C. As can be seen, the small cross is disposed directly to the left of the center of the large cross in the figure for the second center of rotation position686. The distance from the geometric center to the second center of rotation position686can be approximately 1 mm, can be approximately 2 mm, can be approximately 3 mm, can be approximately 4 mm in some embodiments. The distance from the geometric center to the second center of rotation position686can be between 1 and 5 mm inclusive. The distance from the geometric center to the second center of rotation position686can be between 2 and 4 mm inclusive.

In other variations, the center of rotation position can be to the left and below, directly to the right of, to the right and above, or to the right and below, the geometric center.

Providing a patient specific articular body center of rotation offset can advantageously allow the surgeon to better fit the humeral anchor to the specific patient's shoulder. Additional benefits of patient specific articular body center of rotation offset can reduce, minimize or eliminate impingement risk and dislocation risk and can optimize range of motion, stability, and soft tissue tensioning.

8. Humeral Anchors with Patient Specific Metaphysis Portion Inset Depth

FIG.29shows another aspect in which the method500can confirm a manufacturing plan, potentially following a modification of an initial manufacturing plan wherein a patient specific metaphysis portion inset depth is provided. The humeral implant700can have a metaphysis portion708inlay depth724that is initially selected and provided in the step508of the method500. The inlay depth724can be selected initially based upon a relevant population of patients. The inlay depth724can be based on an evaluation such as described in connection withFIG.20C.

FIG.29shows a humeral implant700that can result from the step512and step520, resulting in the metaphysis portion708of the humeral anchor protruding superiorly of a resection surface716when the humeral anchor is implanted within the resected humerus. In particular, an inlay depth724can be provided wherein the metaphysis portion708extends in part above the resection surface716. As can be seen, the inlay depth724relates to the depth that the metaphysis bowl is set into the metaphysis bone and is characterized by the distance from the resection surface716to the superior face720of the metaphysis portion708. The inlay depth724can be between 0 and 20 mm, can be between 5 and 10 mm, can be between 7 and 18 mm, e.g., can be 12 mm.

An inlay depth724of 0 mm places the resection surface716and the superior face720of the metaphysis portion708in alignment. In other variations, the inlay depth724can be a negative value. For example, an inlay depth724can be provided wherein the entire metaphysis portion708sits below the resection surface716. A negative inlay depth724places the superior face720of the metaphysis portion708below the resection surface716. The inlay depth724can be between 0 and −10 mm, e.g. can be −3 mm.

As discussed above in connection withFIGS.16and17, where the outer inferior surface is configured in a patient specific manner, it can be advantageous to provide a patient specific reamer head, such as the reamer head328discussed above.

Providing a patient specific metaphysis portion inset depth can advantageously allow the surgeon to better fit the humeral anchor to the specific patient's shoulder. Additional benefits of patient specific metaphysis portion inset depth can provide more appropriate levels of soft tissue tensioning for the specific patient.

9. Humeral Anchors with Patient Specific Articular Body Jump Distance

FIG.30shows another aspect in which the method500can confirm a manufacturing plan, potentially following a modification of an initial manufacturing plan wherein a patient specific articular body jump distance is provided. The articular body559can have an initial jump distance750that is initially selected and provided in the step508of the method500. The initial jump distance750can be selected initially based upon a relevant population of patients. The initial jump distance750can be based on an evaluation such as described in connection withFIG.20C.

FIG.30shows that an articular body559initial jump distance750is another parameter of a humeral implant that can be made patient specific. In this context, jump distance is defined as the distance from the deepest portion of a concave articular surface748of the articular body559to a superior edge of the articular body559. In part of the method500the appropriateness of the initial jump distance750can be confirmed in the method500, such as in the step512. If a modified jump distance754is deemed suitable, the step520can increase or decrease the initial jump distance750.

In various embodiments, the initial jump distance dimension750can be increased by 1 mm to head 10 mm, can be increased by 2 mm to 8 mm, can be increased by 3 mm to 6 mm. In various embodiments the initial jump distance dimension750can be increased by 2, 4, 8, or 10 mm.

Additional benefits of patient specific articular body jump distance can reduce, minimize, or eliminate dislocation risk and can optimize stability.

10. Humeral Anchors with Patient Specific Articular Body Jump Distance Asymmetry

FIG.31shows another aspect in which the method500can confirm a manufacturing plan, potentially following a modification of an initial manufacturing plan wherein a patient specific articular body jump distance asymmetry is provided. The articular body559C can have jump distance asymmetry that is initially selected and provided in the step508of the method500. The jump distance asymmetry can be selected initially based upon a relevant population of patients. The jump distance asymmetry can be based on an evaluation such as described in connection withFIG.20C. In one variant, the articular body559C can initially be configured in a symmetric manner without any asymmetry in the jump distance. Thereafter, the method500can define asymmetry as discussed below.

FIG.31shows an articular body559C that can result from the step512and the step520, resulting in an articular body559C with patient specific jump distance asymmetry. In particular, an articular body559C can be provided wherein the articular body559C has an increased jump distance portion780and a decreased jump distance portion776. In this context, jump distance asymmetry is defined as the jump distance difference between two portions of a superior edge772of an articular body559C. In part of the method500the appropriateness of the initial jump distance asymmetry can be confirmed in the method500, such as in the step512. If a modified jump distance asymmetry is deemed suitable, the step520can increase or decrease the initial jump distance asymmetry. The methods herein provide for great flexibility in the configuring of the superior edge772to provide optimal jump distance and dislocation control. For example, there can be one high point compared to a neutral (initially defined) jump distance. A high point can be provided at the 12 o'clock position when viewing from the superior side and a low point can be provided at the 6 o'clock position when viewed from the superior side. The position of a high and a low point can be very flexibly defined, such that the high point can be anywhere and the low point also can be anywhere about the superior edge772. Also, the low and high points can be opposite each other, e.g., 180 degrees apart, but can also be closer to each other, such as being 120 degrees from a high point to a low point, 90 degrees from a high point to a low point, 60 degrees from a high point to a low point, 45 degrees from a high point to a low point, or between about 5 degrees and 45 degrees spacing from a high point to a low point. The foregoing angular spacing can be either direction from the 12 o'clock position (e.g., anterior or posterior). Also, more than one high point and/or more than one low point can be provided in certain embodiments. For example, the method500can conclude at the step528with an increased height at the 12 o'clock position, a lower than neutral height at 3 o'clock, an increased height at 6 o'clock, and a lower than neutral height at the 9 o'clock position. Also, where more than one higher or more than one lower position is provided the degree of increase in the height of the superior edge772need not be the same for the portions that are increased. The degree of decrease in height of the superior edge need not be the same for the portions that are decreased. Thus, many adjustments can be made that better configure the articular body559for the specific patient.

Various embodiments can provide different jump distance asymmetry arrangements. For example the increased jump distance portion780can be disposed 1, 2, 4, or 6 mm above a neutral or symmetric jump distance level782. The decreased jump distance portion776can be disposed 1, 2, 4, or 6 mm below a neutral or symmetric jump distance level782. A superior-inferior distance from a decreased portion of the superior edge of the articular body559C and an increased portion of the superior edge can be 1 mm, 2 mm, 4 mm, 8 mm, or 12 mm in various embodiments.

Providing a patient specific articular body jump distance asymmetry can advantageously allow the surgeon to better fit the humeral anchor to the specific patient's shoulder. Additional benefits of patient specific articular body jump distance asymmetry can reduce, minimize, or eliminate dislocation risk and/or notching risk.

IV. Soft Tissue Tension Adapted Humeral Positioning

The foregoing approaches to providing a humeral implant provide many advantages. These approaches can be used in combination with the following humeral positioning system. Likewise, the following systems and methods can be combined with the foregoing systems and methods to provide improved soft tissue tensioning for a patient.

In shoulder arthroplasty, and in particular in reverse shoulder arthroplasty, management of the position of the humerus12in relation to the glenoid18is important to the management of the soft-tissue around the shoulder joint. Soft-tissue management is important for range of motion, stability of the implant (from dislocation), for reducing notching and the chance of acromion stress fractures.FIGS.32and33shows aspects of soft tissue tension management.FIG.32, left image, shows shoulder anatomy prior to surgery, including the center of rotation of the humerus12on the glenoid18. The dimension “A” is a measure of lateral distance that relates to the tension in the rotator cuff bounding the humeral head. The dimension “B” is a measure of arm length or inferior-superior positioning of the humerus relative to the scapula and relates to the tension in the deltoid. Excessive tension in these soft tissues following implantation (e.g., the A′ or B′ dimensions inFIG.32) can result in poor outcomes following the surgery. For example, excessive tension in the deltoid can result in an acromial fracture. A too small A′ dimension (seeFIG.33, left image) may correspond to insufficient tension which can result in a dislocation. A too large A″ dimension (seeFIG.33, right image) may result in excessive cuff tension that would overly restrict range of motion. To provide better outcomes, implant system should be able to adjust position, e.g., of the center of rotation of the humeral system, independently in the medial-lateral direction (e.g., parallel to the dimensions A, A′, A″) and in the inferior-superior direction (e.g., parallel to the dimensions B, B′).

FIGS.34and35illustrate a humeral positioning system800that facilitates managing soft tissue tensioning in a shoulder procedure, such as in reverse shoulder arthroplasty. The humeral positioning system800includes a humeral anchor804and an articular component808. The humeral positioning system800is able to make adjustments in a medial-lateral direction812and to make adjustments in an inferior-superior direction816as discussed further below.

The humeral anchor804includes a stem824that extends to an inferior end828of the humeral anchor804. The humeral anchor804includes a superior end830disposed opposite to the inferior end828. The superior end830includes a mounting portion832disposed at the superior end830. The mounting portion can be enlarged compared to the inferior end828of the stem824. In other embodiments, the humeral anchor804can comprise a stemless anchor which does not include the stem824shown inFIG.34.

The articular component808can include an articular surface850(shown inFIG.34schematically in dashed line). The articular surface850can be curved to have a center of rotation840that can be disposed at a position based on the configuration of the articular component808. In one example, a neutral configuration of the humeral positioning system800can be provided in which a center of rotation840of the articular component808is located on an axis838disposed away from a mounting face836of the humeral anchor804. The mounting face836of the humeral anchor804can be defined at or near the superior end of the mounting portion832and can have a component parallel to the resection surface of the humerus12in one embodiment. The axis838can be disposed perpendicular to the mounting face836in one embodiment. The configuration illustrated inFIG.34can provide a neutral configuration in that the center of rotation840is located on the axis838, perpendicular to the mounting face836. The mounting face836can have a complex structure, e.g., disposed about a mounting channel similar to the mounting channel120discussed above. The mounting face836can have rotational position features disposed therein, as discussed further below and shown schematically inFIG.36.

FIG.34schematically illustrates a matrix M of centers of rotation, with each center of rotation illustrated with a “+” inFIG.34. The matrix M ofFIG.34is also illustrated inFIG.35in table format. The center of rotation840for the selected combination of the humeral anchor804and the articular component808shown inFIG.34is disposed at the lower left-hand portion of the matrix M (see alsoFIG.35). The matrix M has nine positions, but in other embodiments, more or fewer positions may be provided. From the neutral position illustrated inFIG.34an additional configuration can be provided in which the center of rotation is disposed along the axis838farther away from the mounting face836than in the center of rotation840. A first increment along this axis838can provide a second center of rotation840′ (seeFIG.35) of a humeral positioning system800including the humeral anchor804and a second, different articular component808that is thicker (as compared with the articular component that provides the center of rotation40) along the direction of the axis838. For example, the second articular component808can be thicker than the articular component808by the magnitude of the increment from the center of rotation840at the lower left position of the matrix M to a position in the center of the matrix M. A second increment along the axis838can provide a center of rotation840″ (seeFIG.35) of a humeral positioning system800including the humeral anchor804and a third, different articular component808that is thicker along the direction of the axis838by the magnitude of the increment from the center of rotation840at the lower left position of the matrix M to a position at the upper right of the matrix M. The position of the center of rotation840relative to the first and second increments provide simultaneous adjustment in both the medial-lateral direction812and the inferior-superior direction816, as these first and second increments lie along the axis838.

While these adjustments are useful, the matrix M illustrated inFIGS.34and35has additional positions in which the adjustment in the medial-lateral direction812and in the inferior-superior direction816are not one-to-one. For example, the matrix M illustrated inFIGS.34and35has an increment immediately superior to the location of the center of rotation840for the neutral configuration to define a first superior center of rotation841. This increment provides an adjustment in only the inferior-superior direction816and no adjustment in the medial-lateral direction812relative to the position of the center of rotation840. The matrix M can also include a second increment immediately superior to the first superior center of rotation841so as to define a second superior center of rotation841′. The increments to the center of rotation841and the center of rotation841can be equal, e.g., 3 mm. In some embodiments, the increments can be in increments other than 3 mm, but may be in otherwise generally equal increments. In various embodiments, the increments can be in a range of 0.5 mm to 5 mm, in a range of 1 mm to 5 mm, in a range of 1.5 mm to 4.5 mm, or in a range of 2 mm to 4 mm.

Similarly, the matrix M illustrated inFIGS.34and35has a third increment immediately lateral to the location of the center of rotation840for the neutral configuration to define a first lateral center of rotation843. This third increment provides an adjustment in only the medial-lateral direction812and no adjustment in the superior-inferior direction816relative to the position of the center of rotation840. The matrix M can also include a fourth increment immediately lateral to the first lateral center of rotation843to define a second lateral center of rotation843′. Further, as shown in the matrix M, fifth and sixth increments can provide both lateral and superior adjustments relative to the center of rotation840shown inFIG.35, such that centers of rotation845,845′ may be offset along both the lateral-medial axis812and the superior-inferior axis816.FIG.36shows that the increments to the centers845,845′ can be by different amounts in the medial-lateral direction812than in the inferior-superior direction816The center845can be disposed superiorly from the center of rotation840by a greater amount, e.g., by twice as much, in the inferior-superior direction816than in the medial-lateral direction812. The center845′ can be disposed laterally from the center of rotation840by a greater amount, e.g., by twice as much, in the medial-lateral direction812than in the inferior-superior direction816.

As described above, the humeral positioning system800can include a humeral anchor804and an articular component that when mated to the humeral anchor804locates the center of rotation at any one of the increments inFIGS.34and35. The humeral positioning system800can be provided by selecting an articular component that provides the appropriate increment and coupling the selected body with the humeral anchor804to provide an increment that yields the desired soft tissue tension.

FIG.36illustrates a kit890that can include the humeral anchor804(which may be a stemmed or stemless anchor) and one or more of the articular components808. In the illustrated embodiment, the kit890includes the humeral anchor804, the articular component808, a second adjusted articular component894configured for adjustment along the medial-lateral direction812, and a third adjusted articular component898for an adjustment along the inferior-superior direction816. The articular component808includes an engagement portion846and an articular surface850disposed on opposite sides thereof. The engagement portion846is configured to engage the mounting face836of the humeral anchor804in any suitable manner, such as by a c-ring, interference fit or any of the configurations disclosed above, all of which shall supplement the disclosure provided here. Similarly, the second adjusted articular component894can comprise an engagement portion846′ and an articular surface850′ opposite from the engagement portion846′. The articular surface850′ in the second adjusted articular component894is shifted relative to the position of the articular surface850in the articular component808. The shifted position causes the center of rotation of the second adjusted articular component894to be correspondingly shifted. The third adjusted articular component898can comprise an engagement portion846″ and an articular surface850″ opposite from the engagement portion846″. The articular surface850″ in the second adjusted articular component898is shifted relative to the position of the articular surface850in the articular component808. The shifted position causes the center of rotation of the second adjusted articular component898to be correspondingly shifted.

In some embodiments, the number of articular bodies to provide a plurality of increments, such as are illustrated in the matrix M ofFIGS.34and35can be less than the number of increments in the matrix M. In one approach, at least one of the second adjusted articular component894and the third adjusted articular component898can be configured to be coupled with the humeral anchor804in a plurality of (e.g., two) positions to provide two distinct increments in the matrix M ofFIGS.34and35. For example, the second adjusted articular component894can be configured to be coupled with the humeral anchor804in a first position to provide an increment of adjustment in the medial-lateral direction812, such that the center of rotation may correspond to the first lateral center of rotation843ofFIG.35. The humeral anchor804can have a first rotational positioning feature864. The second adjusted articular component894can have a second rotational position feature868. The first rotational positioning feature864and the second rotational position feature868can engage with one another to enable the humeral anchor804to be secured to each other in a discrete pre-defined position. The position can be one that provides a desired position, e.g., a desired increment in the medial-lateral direction812without any adjustment in the inferior-superior direction816. For example, referring to the matrix M ofFIG.35, when the first rotational positioning feature864is engaged with the second rotational position feature868, the center of rotation can correspond to the first lateral center of rotation843, as explained above. Thus, the second and third articular components894,898can include clocking or rotational figures to place one or both of the components894,898in two positions, e.g., two positions 180 degrees apart, so as to provide inferior-superior and lateral-medial adjustment. In other embodiments, however, one or more of the second and third articular components894,898can include clocking or rotational features configured to place the components894,898in more than two positions, e.g., in three, four, five, six, seven, eight, nine, ten, or more positions so as to provide adjustment along interior-superior and lateral-medial directions. In various embodiments, the different clocking positions may be evenly spaced.

In one embodiment, the mounting face836of the humeral anchor804can have a third rotational positioning feature874. The third rotational positioning feature874can be secured or positioned relative to the first rotational positioning feature864such that the second adjusted articular component894is rotated 180 degrees from the position in which the first rotational positioning feature864is coupled to the second rotational position feature868. For example, the second rotational positioning feature868of the second adjusted articular component894can engage with the first rotational positioning feature864of the anchor864to provide the 180 degree rotation. In some embodiments, the second and third rotational positioning features can be disposed 180 degrees circumferentially from one another. The rotation by 180 degrees can enable the second adjusted articular component894to provide an increment in the inferior-superior direction816without providing any increment in the medial-lateral direction812. For example, when the first and third rotational positioning features864are engaged, the center of rotation can correspond to the first superior center of rotation841shown inFIG.35. Thus, one modified embodiment of the kit890provides the second adjusted articular component894able to provide the centers of rotation841,843. In this embodiment, the third adjusted articular component898could be provided to offer the centers of rotation841′,843′.

Because the second adjusted articular component894can have two positions, the second adjusted articular component894can include a marking adjacent to the second rotational position feature868or the third rotational positioning feature874so that the surgeon is advised of whether the adjustment is being made in the medial-lateral direction812or in the inferior-superior direction816by coupling of the second rotational position feature868with the first rotational positioning feature864or by the coupling of the third rotational positioning feature874with the first rotational positioning feature864. The rotational positioning features864,868,874described in connection withFIG.36can comprise any suitable type of rotational orientation device, e.g., a lock-and-key mechanism, a projection-recess mechanism, etc.

In some embodiments, a third adjusted articular component can be shaped to provide a first incremental offset of a center of rotation of the articular surface relative to the center of rotation840of the neutral configuration in a medial-lateral direction812and a second incremental offset of the center of rotation relative to the center of rotation840of the neutral configuration in an inferior-superior direction816when the engagement portion is coupled with the mounting surface836of the humeral anchor804. For example, in some embodiments, the articular surface can be shaped to provide a center of rotation845or845′ (seeFIG.35) that provides rotational offset in both the medial-lateral direction812and the inferior-superior direction816. For example, the thickness and/or curved profile of the articular surface can be designed to provide both lateral and superior offsets, as shown inFIG.35. In one embodiment, the thickness of the articular component808can be increased in a direction corresponding to the axis838and the position of the articular surface850can be shifted as illustrated in the articular surface850′ to provide a greater increment in the medial-lateral direction812than in the inferior-superior direction816. In one embodiment, the thickness of the articular component808can be increased in a direction corresponding to the axis838and the position of the articular surface850can be shifted as illustrated in the articular surface850″ to provide a greater increment in the inferior-superior direction816than in the medial-lateral direction812.

FIG.37provides a cross-section schematic in which three articular surfaces850,850′,850″ and the corresponding centers of rotation are illustrated.FIG.37is schematic only and is intended to show the articular surfaces and their corresponding centers of rotation. The humeral positioning system800and the kit890enable any of these three surfaces850,850′,850″ and centers of rotation to be provided based on selection and, in some cases orientation, of the appropriate articular component808. For example, as explained above, the articular surface850can be disposed such that the center of rotation840is along the axis838. The articular surface850′ can be disposed and shaped such that the first lateral center of rotation843is laterally offset relative to the center of rotation840. Similarly, the articular surface850″ can be disposed and shaped such that the first superior center of rotation841is offset along the superior direction relative to the center of rotation840.

FIG.36also illustrates a method of selecting and implanting a humeral positioning system800in a patient. The method can commence with an assessment of soft tissue of the patient to determine what degrees of off-set should be provided post-operatively in the patient. The surgeon can access a shoulder joint of a patient in any suitable manner and can remove a humeral head from a distal humerus H. The surgeon can secure the humeral anchor840to the distal humerus H. For example, in some embodiments, the surgeon can bore out or compress a portion of the humerus H, and can insert a stem of the anchor840into the opening. In some embodiments, the surgeon can assess a position of the scapula and/or the humerus12to determine a desired position of an articular surface850(or850′ or850″) of the humeral positioning system800.

The surgeon can select an articular component808from a plurality of pre-made humeral components including at least one humeral components capable of independently adjusting medial-lateral and inferior-superior offsets, as explained above in connection withFIG.35, for example. The selected articular component808can provide the desired position of the articular surface850(or850′ or850″) when the articular component808is coupled with the humeral anchor840and is in contact with an articular component808coupled with the scapula.

The surgeon can then bring the selected articular component to the humeral anchor804as indicated by the arrow895. In some embodiments, as explained in connection with, for example,FIG.36, surgeon can align the first rotational position feature864of the humeral anchor840with the second rotational position feature874of the articular component, e.g., by rotating the component about the axis897. The surgeon can secure the engagement portion846of the articular component808(or articular component894or articular component898) to the mounting portion of the humeral anchor840with the first rotation position feature864aligned with the second rotational position feature874.

In some embodiments, assessing the position of the scapula relative to the humerus can be performed pre-operatively on the basis of imaging of the patient.

After the articular component is aligned, e.g., rotationally aligned, with the humeral anchor804the humeral positioning system800can be fully assembled to provide the desired soft tissue tensioning.

Terminology

Although certain embodiments have been described herein, the implants and methods described herein can interchangeably use any articular component, as the context may dictate.

As used herein, the relative terms “proximal” and “distal” shall be defined from the perspective of the humerus. Thus, proximal refers to the direction of the end of the humerus adjacent to the scapula and forming part of the shoulder joint, which may be referred to herein as the superior direction, end or portion, and distal refers to the direction away from proximal, which can be the end of the humerus forming part of the elbow joint and which may be referred to herein as the inferior direction, end or portion of the humerus.

Conditional language, such as “can,” “could,” “might,” or “may,” unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements, and/or steps. Thus, such conditional language is not generally intended to imply that features, elements, and/or steps are in any way required for one or more embodiments.

The terms “comprising,” “including,” “having,” and the like are synonymous and are used inclusively, in an open-ended fashion, and do not exclude additional elements, features, acts, operations, and so forth. Also, the term “or” is used in its inclusive sense (and not in its exclusive sense) so that when used, for example, to connect a list of elements, the term “or” means one, some, or all of the elements in the list. In addition, the articles “a,” “an,” and “the” as used in this application and the appended claims are to be construed to mean “one or more” or “at least one” unless specified otherwise.

The ranges disclosed herein also encompass any and all overlap, sub-ranges, and combinations thereof. Language such as “up to,” “at least,” “greater than,” “less than,” “between,” and the like includes the number recited. Numbers preceded by a term such as “about” or “approximately” include the recited numbers and should be interpreted based on the circumstances (e.g., as accurate as reasonably possible under the circumstances, for example ±5%, ±10%, ±15%, etc.). For example, “about 1” includes “1.” Phrases preceded by a term such as “substantially,” “generally,” and the like include the recited phrase and should be interpreted based on the circumstances (e.g., as much as reasonably possible under the circumstances). For example, “substantially spherical” includes “spherical.” Unless stated otherwise, all measurements are at standard conditions including temperature and pressure.

As used herein, a phrase referring to “at least one of” a list of items refers to any combination of those items, including single members. As an example, “at least one of: A, B, or C” is intended to cover: A, B, C, A and B, A and C, B and C, and A, B, and C. Conjunctive language such as the phrase “at least one of X, Y and Z,” unless specifically stated otherwise, is otherwise understood with the context as used in general to convey that an item, term, etc. may be at least one of X, Y or Z. Thus, such conjunctive language is not generally intended to imply that certain embodiments require at least one of X, at least one of Y and at least one of Z to each be present.

Although certain embodiments and examples have been described herein, it should be emphasized that many variations and modifications may be made to the humeral head assembly shown and described in the present disclosure, the elements of which are to be understood as being differently combined and/or modified to form still further embodiments or acceptable examples. All such modifications and variations are intended to be included herein within the scope of this disclosure. A wide variety of designs and approaches are possible. No feature, structure, or step disclosed herein is essential or indispensable.

Some embodiments have been described in connection with the accompanying drawings. However, it should be understood that the figures are not drawn to scale. Distances, angles, etc. are merely illustrative and do not necessarily bear an exact relationship to actual dimensions and layout of the devices illustrated. Components can be added, removed, and/or rearranged. Further, the disclosure herein of any particular feature, aspect, method, property, characteristic, quality, attribute, element, or the like in connection with various embodiments can be used in all other embodiments set forth herein. Additionally, it will be recognized that any methods described herein may be practiced using any device suitable for performing the recited steps.

For purposes of this disclosure, certain aspects, advantages, and novel features are described herein. It is to be understood that not necessarily all such advantages may be achieved in accordance with any particular embodiment. Thus, for example, those skilled in the art will recognize that the disclosure may be embodied or carried out in a manner that achieves one advantage or a group of advantages as taught herein without necessarily achieving other advantages as may be taught or suggested herein.

Moreover, while illustrative embodiments have been described herein, it will be understood by those skilled in the art that the scope of the inventions extends beyond the specifically disclosed embodiments to any and all embodiments having equivalent elements, modifications, omissions, combinations or sub-combinations of the specific features and aspects of the embodiments (e.g., of aspects across various embodiments), adaptations and/or alterations, and uses of the inventions as would be appreciated by those in the art based on the present disclosure. The limitations in the claims are to be interpreted broadly based on the language employed in the claims and not limited to the examples described in the present specification or during the prosecution of the application, which examples are to be construed as non-exclusive. Further, the actions of the disclosed processes and methods may be modified in any manner, including by reordering actions and/or inserting additional actions and/or deleting actions. It is intended, therefore, that the specification and examples be considered as illustrative only, with a true scope and spirit being indicated by the claims and their full scope of equivalents.

Any methods disclosed herein need not be performed in the order recited. The methods disclosed herein include certain actions taken by a practitioner; however, they can also include any third-party instruction of those actions, either expressly or by implication. For example, actions such as “inserting a humeral stem into a humerus” include “instructing insertion of a humeral head into a humerus.”