Humeral fixation plate guides

An anchor trajectory guide and methods of use thereof are provided. The guide includes a body that has a medial side. The medial side can be placed over a lateral side of a fixation plate. The anchor trajectory guide also includes a locator and a plurality of guide apertures. The locator is disposed on or through the medial side of the body. The locator can be mated with the fixation plate. The guide apertures are disposed through the body at positions corresponding to define anchor locations and orientations to provide good purchase adjacent to or in cortical bone around a medial side of a humerus.

INCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATIONS

BACKGROUND OF THE INVENTION

Field of the Invention

This application is directed to guides for controlled insertion of fasteners into bone fracture plates, e.g., for the humerus, and for fracture repair and methods of using the same.

Description of the Related Art

Humeral fractures arise from serious injuries and other causes. One approach to repairing fracture involves attaching a fracture plate to an outside surface of the humerus to fix exposed sides of the facture onto or adjacent to one another to facilitate the process of fusing these exposed sides together. The fracture plate assures that the multiple pieces of the fractured bone remain in a prescribed position or orientation to each other and do not move relative to each other so that the fusion process is not continually disrupted and so that the bones do not migrate to and fuse in misaligned positions.

Humeral bone has several layers. An outer layer called the cortical layer is a relatively dense portion of the humerus that is most capable of bearing loads absent other bone considerations. Inward of the cortical layer is cancellous bone matter. This bone matter is less dense and is not as capable of bearing loads. A number of screws can be used to secure a fracture plate to the humerus. These screws should be lodged in the cortical bone or in a transition between cancellous and cortical bone to provide good fixation of the fracture plate to the bone, and thereby of the multiple pieces of the fractured humerus to each other.

Because fracture plates are typically coupled with the lateral side of the humerus and the screws are typically directed into the humeral head, it is important to control the final location of the tips of the screws.

SUMMARY OF THE INVENTION

It would be desirable to provide improved apparatuses and methods for securing a fracture plate to a humerus. It would be advantageous to provide a guide that can be used to direct fasteners into the humeral bone in a way that provides robust connection of the fasteners to strong bone, e.g., to cortical bone, of the humerus. In some applications the guides can be configured to provide a prescribed pattern of fasteners projecting from a fracture plate. The prescribed pattern can be controlled by a guide that is appropriate for the humerus, e.g., appropriate for the size and location (left, right) of the humerus. The prescribed pattern could be unique to a specific patient based on pre- or intra-operative imaging. The guides can enable a non-patient specific fracture plate to be used with humerus bones of different size and in some cases in patient specific method, e.g., resulting in proper placement of the fracture plate and of a plurality of fasteners.

In one embodiment, an anchor trajectory guide is provided that includes a body that has a medial side. The medial side is configured to be placed over a lateral side of a fixation plate. The anchor trajectory guide also includes a locator and a plurality of guide apertures. The locator is disposed on or through the medial side of the body. The locator is configured to mate with the fixation plate. The guide apertures are disposed through the body at positions corresponding to define anchor locations and orientations to provide good fixation in bone around a medial portion of a humerus.

In another embodiment an anatomical guide is provided. The anatomical guide is configured to be coupled with a sleeve and a visual guide member. The sleeve is configured to mate with a guide aperture of an anchor trajectory guide or with a fixation plate. The sleeve can have a lumen that is disposed therethrough. The lumen can be used to advance a K-wire or other pin through the anatomical guide. The visual guide member is configured to extend from the anchor trajectory guide or the fixation plate to an anterior side or a posterior side of the humerus.

In another embodiment a method is provided. In the method, a medial side of a fixation plate is placed on a lateral surface of a humerus. The fixation plate is placed in contact with the lateral surface. The fixation plate is coupled with the humerus spanning a fracture. A medial side of an anchor trajectory guide is coupled with a lateral side of the fixation plate. An anchor channel is formed in the humerus from the lateral side of the humerus toward an opposing cortical bone region. The anchor channel can be formed, through a guide aperture in the anchor trajectory guide and an anchor aperture in the fixation plate. An anchor is advanced through the anchor aperture and the anchor channel, which is formed in the bone, to secure the anchor and the fixation plate to the humerus. The anchor follows a trajectory defined by the anchor trajectory guide. A medial end of the anchor is embedded in or adjacent to the opposing cortical bone while a proximal end of the anchor is embedded in lateral cortex of the humerus. When the medial end is embedded adjacent to opposing cortical bone the medial end can be lodged in cancellous bone. When the medial end is embedded adjacent to opposing cortical bone the medial end can be lodged in a transitional bone matter between the cancellous bone and the cortical bone.

In another embodiment, a slot anchor guide is provided that includes a medial portion and a lateral portion. The medial portion has a medial projection configured to span a slot of a fixation plate. The slot anchor guide is configured to guide an anchor through a predetermined position of a slot of the fixation plate. The slot anchor guide is configured to mate with the fixation plate to allow a surgeon to place the fixation plate on a bone face by manipulating the lateral portion.

In another embodiment, a tuberosity fracture plate is provided. The tuberosity fracture plate has a tuberosity end, a distal portion, a first screw hole and a second screw hole. The tuberosity end has a first portion configured to overlay a first tuberosity and a second portion opposite the first portion. The distal portion is coupled with and extends away from the tuberosity portion. The first screw hole is disposed in the tuberosity end. The second screw hole is disposed in the distal portion. The tuberosity fracture plate has a bend zone disposed between the first screw hole and the second screw hole. The bend zone is configured to locate a bend in the tuberosity fracture plate between the first screw hole and the second screw hole upon application of a load to the tuberosity end, to the distal portion or to both the tuberosity end and the distal portion.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

This application is directed to a guide for attaching a fixation plate to a humerus of a patient and to plates that can be so attached. The guide could be used following a fracture. The fracture can be between the metaphysis and the diaphysis of the humerus or along a prominence of a proximal portion of a humerus, such as a tuberosity. Although the guides and methods are described in connection with the humerus the guides and methods can be used for other bones, such as any long bone fracture or for other orthopedic plate fixation procedures.

FIG. 1shows anatomy of a glenohumeral joint. The joint is formed in part by a head10of a humerus H and a glenoid18of a scapula14. The head10is a convex structure that is generally spherical. The glenoid18includes a concave articular surface upon which the head10moves.FIG. 1Ashows that the humerus H has a medial side (right side in the view) and a lateral side (left side in the view). The medial calcar MC is located at the inferior edge of the head10on the medial side of the humerus. A lateral cortex LC extends along the lateral side of the bone generally opposite to the medial calcar MC. An anterior-superior region AS of the humerus H is located on the lateral side and superior to the distal-proximal location of the medial calcar MC.

As discussed above, the humerus has a proximal portion that is the portion of the humerus adjacent to the glenoid18and forming part of the shoulder joint. The proximal humerus is sometimes referred to herein as the superior humerus. Proximal and distal in this sense are shown onFIG. 1Awith reference to the humerus. In this application a location that is distal to another location refers to being closer to an inferior or elbow-adjacent end of the humerus. A distal portion of the humerus is sometimes referred to herein as an inferior portion of the humerus.

FIG. 1Ashows a fracture F which is one simple form of fracture that can be treated by the apparatuses and methods discussed below. In many cases the fracture F is accompanied by additional fractures around the humeral head10. These additional fractures can be treated as well, as discussed further below.

FIGS. 1B and 1Cshow an example of a tuberosity fracture TF that can be treated as discussed below with a plate that is suitable for repairing the tuberosity fracture TF. The tuberosity fracture TF is of a greater tuberosity GT but could be of the lesser tuberosity LT or another prominence of a long bone.

FIG. 2shows how a fracture F in a humerus H can be treated using a fixation plate assembly90. The fixation plate assembly90includes a fixation plate100and a plurality of polyaxial anchors130in one embodiment. The fixation plate100can have a lateral side108configured to face away from the humerus H and a medial side112(seeFIG. 7) configured to face the humerus H. The medial side112can be in direct contact with a lateral surface LS of the humerus H in some applications. The fixation plate100preferably is configured to work well for an entire population of patients. The proximal-distal dimensions enable the fixation plate100to span a wide range of neck fractures. The anterior-posterior dimensions allow the fixation plate100to be placed on the lateral surface LS of a wide range of bone sizes.

The fixation plate100can include a distal portion116and a proximal portion118. In some methods, the distal portion116is disposed between the humeral neck and the end of the humerus H forming a portion of the elbow joint. In some methods, the distal portion116is disposed between the fracture F and the end of the humerus H forming a portion of the elbow joint. In some methods the proximal portion118is positioned proximal of the humeral neck or of the fracture F. The proximal portion118can be configured to be secured to the lateral surface LS of the humerus H in the region of the head of the humerus H. For example, the proximal portion118can include an array of anchor apertures134. The anchor apertures134can be disposed about the periphery of the proximal portion118of the fixation plate100. In one embodiment, there are four anchor apertures134on an anterior side of the proximal portion118and there are an additional four anchor apertures134on a posterior side of the proximal portion118of the fixation plate100. In some variations there can be more than four anchor apertures134on the anterior and posterior sides. In some variations there can be more anchor apertures134on the anterior than on the posterior side. In some variations there can be more anchor apertures134on the posterior than on the anterior side.

One or more or all of the anchor apertures134can be suited to mate with polyaxial anchors130. The engagement between the polyaxial anchor130and the anchor aperture134allow the anchor to be directed along a range of directions rather than just being directed along a single axis as is provided with a more simple thread arrangement. As discussed further below, the fixation plate100enables a medial end142of the polyaxial anchors130to span across cancellous bone of the humerus H to engage an opposing cortical bone region CB. A lateral end146of the polyaxial anchors130is configured to engage cortical bone at or adjacent to the lateral surface LS of the humerus H. The lateral end146also has a head portion134A that is configured to engage a corresponding one of the anchor apertures134.

FIG. 2andFIG. 27show that when the fixation plate100is coupled with a humerus H the polyaxial anchors130are generally splayed out. In this specification two anchors are splayed when they are disposed in space along longitudinal axes that are not parallel to each other.FIGS. 2 and 27show that the anchors130are generally splayed out with respect to a medial-lateral and proximal-distal plane PL of the humerus H. That is, a plurality of, e.g., four, polyaxial anchors130can be secured through an anterior portion of the fixation plate100to the lateral surface LS of the humerus H. Another plurality of, e.g., four, polyaxial anchors130can be secured to a posterior portion of the fixation plate100to the lateral surface LS of the humerus H. The polyaxial anchors130can be oriented such that medial ends142thereof are more anterior or more posterior than are lateral ends146thereof. Described another way, the lateral ends146can be located closer to the medial-lateral and proximal-distal plane PL than are the medial ends142thereof.FIG. 2andFIG. 27also show that the fixation plate100can be configured to engage some anchors along the medial-lateral and proximal-distal plane PL. For example, one polyaxial anchor130can be disposed on the medial-lateral and proximal-distal plane PL in a central portion of the fixation plate100. Also, one or a plurality of, e.g., two, polyaxial anchors130can be secured to anchor apertures134in the distal portion116of the fixation plate100and therethrough to a portion of the humerus H distal to the head10or distal to the fracture F.

Some advantageous methods discussed herein aid in initial placement of the fixation plate100such that the initial placement normally does not require repositioning and thus is normally the final placement. The fixation plate100includes a slot160in the distal portion116that facilitates some of these methods. The slot160can extend along a length of the distal portion116. In some embodiments the slot160is aligned with a longitudinal axis of the fixation plate100and so can be positioned to symmetrically straddle the medial-lateral and proximal-distal plane PL. The slot160can have a smooth inner surface161to engage with a non-locking anchor132(seeFIG. 2). The slot160allows the fixation plate100to move in a proximal-distal direction and also to rotate about the non-locking anchor132prior to placement of other anchors through the fixation plate100.

The fixation plate100can have one or a plurality of suture apertures164disposed about the periphery thereof. The suture apertures164enable a surgeon to secure fracture portions to the fixation plate100. In some cases fractured portions of the head can include the greater and/or the lesser tuberosities. These bone portions are usually attachment points for soft tissue, e.g., rotator cuff portions. The soft tissue tends to pull these fractured pieces medially. The suture apertures164can be used to pull these fracture pieces back laterally to engagement with the rest of the head10of the humerus H such that the humerus can heal properly. In the illustrated embodiment there are four suture apertures164on each of the anterior and posterior side of the fixation plate100. Also, there can be one or two suture apertures164on the proximal end of the fixation plate100. In some embodiments, the suture apertures164on the anterior side of the fixation plate100are oriented anteriorly. In some embodiments, the suture apertures164on the posterior side of the fixation plate100are oriented posteriorly. The suture apertures164can be oriented away from the center of the fixation plate100.

Certain embodiments are configured to keep the fixation plate100on a small surface area. Accordingly, the fixation plate100can be located on the lateral surface LS and not extend around to the anterior surface or the posterior surface of the humerus H. In some cases, the fixation plate100includes scallops168that are located between the suture apertures164. The scallops168reduce the anterior and posterior extent of the fixation plate100, keeping the plate as low profile in the anterior and posterior directions.

The fixation plate100can be configured to mate with an anchor trajectory guide200, which is discussed below inFIGS. 3-6. For example, the fixation plate100can have a locating aperture120. The locating aperture120can extend from the lateral side108toward the medial side112. The locating aperture120can extend from the lateral side108to an end portion within the thickness of the fixation plate100, e.g., as a blind hole. The locating aperture120can extend entirely through the thickness of the fixation plate100from the lateral side108to the medial side112. Other approaches can be provided to mate the anchor trajectory guide200with the fixation plate100can include providing a protrusion on the lateral side108of the fixation plate100that extends laterally toward and into the anchor trajectory guide200. In some cases, the lateral side108has contours that mate in a positive-negative manner with a medial side208of the anchor trajectory guide200. In this sense positive-negative manner refers to a concavity in one of the lateral and medial sides108208being configured to be received in a convexity formed at a corresponding location of the other of the lateral and medial sides108,208.

The fixation plate100can also include a coupling aperture172that can used to further secure the fixation plate100to the anchor trajectory guide200. The coupling aperture172can also be seen inFIG. 7F. The coupling aperture172can be a through-hole or a blind recess. The coupling aperture172can include threads to engage a screw that is advanced through the anchor trajectory guide200as discussed further below.

In some cases, it may be beneficial to form the fixation plate100as a patient specific device. For example the medial side112of the fixation plate100in the proximal portion118can be formed with a curvature matching the curvature of the head10of the humerus H of the specific patient being treated. Also, the location of a change in curvature or profile from the proximal portion118to the distal portion116can be selected to match the location of the transition from the long shaft portion of the humerus H to the head10thereof. Also, although the anterior-posterior coverage of the fixation plate100is generally kept as small as possible, the curvature in this direction on the medial side112of the fixation plate100can be configured to match that of the lateral surface LS of the humerus H. An anterior-posterior curvature of the medial side112in the proximal portion118can be different from, e.g., larger than, that of the distal portion116of the fixation plate100.

A process for forming a patient specific version of the fixation plate100can include obtaining imaging of (e.g., pre- or intra-operative imaging) a humerus. The imaging can be that of the humerus H that is affected and to be treated. In certain fractures portions of the lateral surface LS are not altered by the fracture. For example, the fracture illustrated inFIG. 3does not affect the lateral surface LS of the head10of the humerus H. So, the curvature thereof can be obtained even from an image of the fractured humerus H. Similarly the curvature of the humerus H distal the fracture F may be unaffected by the fracture. In other cases the fracture is such that the form of the lateral surface LS of the humerus H in the fracture state does not provide good information about the proper shape of the fixation plate100. In such cases, imaging (either pre-operative or intra-operative) of the contralateral humerus H can provide a good approximation of patient specific features discussed above. Once the form of the fixation plate100is determined from the imaging the fixation plate100can be formed using additive manufacturing techniques, such as3D printing, DMLS, and other similar techniques.

FIG. 2Aillustrates a humeral fixation plate100A that is similar to the humeral fixation plate100except as described differently above or elsewhere herein. The disclosure of the humeral fixation plate100can supplement the disclosure of the humeral fixation plate100A. The disclosure of the humeral fixation plate100A can supplement the disclosure of the humeral fixation plate100

The humeral fixation plate100A includes a lateral side108and a medial side112. The lateral side108is the portion of the humeral fixation plate100A that faces away from the humerus H when the humeral fixation plate100A is applied thereto. The medial side112is the portion of the humeral fixation plate100A that contacts the humerus H when the humeral fixation plate100A is applied thereto. The humeral fixation plate100A has a thickness between the lateral side108and medial side112that can be uniform such that the plate is generally uniformly stiff along a longitudinal axis159thereof. For example, the humeral fixation plate100A can respond to typical load in surgery by not preferentially bending at any particular location there. In a modified embodiment, the humeral fixation plate100A can have a bend zone, e.g., a thinner region as discussed below in connection with the tuberosity fracture plate600such that the humeral fixation plate100A can be shaped intra-operatively.

The humeral fixation plate100A can have a distal portion116and a proximal portion118. The proximal portion118generally can be configured to overlay a proximal portion of the humerus H when applied thereto. The distal portion116can be configured to extend distal of the metaphysis of the humerus H and can overlay a portion of a diaphysis of the humerus H when applied thereto. In some applications the distal portion116can be disposed across a fraction of the humerus H, e.g., as shown inFIGS. 1A and 2. The proximal portion118can be configured to be connected to a head portion of the humerus H. The proximal portion118can be wider in a direction transverse to the longitudinal axis159and to the thickness of the humeral fixation plate100A than is the distal portion116.

The humeral fixation plate100A can have a slot160A that is similar to the slot160except as described differently. The slot160A can be disposed through the distal portion116from the lateral side108to the medial side112of the humeral fixation plate100A. The slot160A can extend along the longitudinal axis159. The slot160A can extend from a first end162to a second end163along the longitudinal axis159. The first end162can be disposed adjacent to the proximal portion118. The second end163can be disposed adjacent to the distal end of the humeral fixation plate100A. The slot160A enables the surgeon to adjust the position of the humeral fixation plate100A relative to the humerus H along a proximal-distal (or inferior-superior) direction.

The slot160A can have a plurality of discrete position sites167that assist in the process of placing the humeral fixation plate100A. The plurality of discrete position sites167are useful when the humeral fixation plate100A is repositioned during the use thereof, as discussed further below. The plurality of discrete position sites167can include a plurality of concavities167A. The concavities167A can include scallop disposed along the length of the slot160A. A non-locking anchor132can be placed in the slot160A (seeFIGS. 2B-C).

The slot160A also can include a visual spacing indicator169disposed along the slot160A. The visual spacing indicator169can include one or a plurality of lines171. The lines171can be formed transverse to the longitudinal axis159. The lines171can extend away from the slot160A toward a perimeter of the distal portion116. In one embodiment, each of the lines171extends from a central portion of one of the concavities167A. The lines171can be provided on one side of the slot160A or on both sides of the slot160A.

The spacing between the lines171can be provided to assure that repositioning of the humeral fixation plate100A is successful. For example, the spacing between the lines171can assure that a K-wire296placed through a positioning channel296A of the humeral fixation plate100A will not be in a same bone location after repositioning the plate100A as when the K-wire296was initially placed through the positioning channel296A of the plate100A.

II. Anchor Trajectory Guides and Methods

As noted above it is desired to have the polyaxial anchors130extend through the humerus H such that the medial ends142thereof extend to and are lodged in opposing cortical bone region CB. The cortical bone region CB of the head10of the humerus H is an outer shell of the head. It is desired that the contact surface between the medial side112of the fixation plate100and the lateral surface LS of the humerus H be bounded by a smaller area than an area bounding all of the medial ends142of the polyaxial anchors130. As noted above, the polyaxial anchors130generally are implanted in a splayed orientation to achieve this. Because the bone of the humerus H is irregular it is not a simple task to assure that the medial ends142of the polyaxial anchors130reach the opposing cortical bone region CB through the anchor apertures134of the fixation plate100while, in some applications, at the same time achieving a high degree of splaying. Furthermore, because patients are of different sizes, a proper splayed arrangement for a large patient may result in exposed screw tips on the medial side of the humerus which could even be exposed in the articular surface. This result would be disadvantageous as potentially resulting in scoring of or otherwise damaging the articular surface of the glenoid. The anchor trajectory guide200helps to solve these problems.

The anchor trajectory guide200includes a body204that has a medial side208and lateral side212. The medial side208is a first side and the lateral side212is a second side. The medial side208is configured to mate with, e.g., to be in direct contact with, the lateral side108of the fixation plate100as discussed above and further below. The lateral side212is exposed when the anchor trajectory guide200is coupled with the fixation plate100such that access can be provided to a plurality apertures, including a plurality of guide apertures232, a pin aperture236, and a fastener aperture237(seeFIG. 4). In one embodiment a plurality of, e.g., six, guide apertures232are provided in a proximal portion218of the anchor trajectory guide200and a plurality of, e.g., three, guide apertures232are provided in a distal portion216of the anchor trajectory guide200. The guide apertures232can extend from a first opening on the medial side208to a second opening on the lateral side212.

The proximal portion218of the anchor trajectory guide200is configured to be disposed over the proximal portion118of the fixation plate100when the fixation plate100and the anchor trajectory guide200are coupled together. At least the medial side112and in some cases both the medial side112and the lateral side108of the proximal portion118are arcuate in form. The fixation plate100preferably has a concavity on the medial side112such that the convexity of the humerus H can be received in or accommodated in the proximal portion118of the fixation plate100. The concavity on the medial side112may be generic or patient specific. The distal portion116of the fixation plate100generally extends along the neck region and distal of the neck region of the humerus H and thus has less or no concavity in the proximal-distal direction. The distal portion116extends from an end of the proximal portion118.

Due to the shape of the fixation plate100and the configuration of the anchor trajectory guide200to nest in or on the fixation plate100, the proximal portion218is gradually thinner in the medial-lateral direction toward the proximal terminal end of the anchor trajectory guide200. Thus, the proximal portion218is gradually thicker in the medial-lateral direction toward the distal portion216. The variation in thickness is due to the configuration of the anchor trajectory guide200to accommodate the arcuate shape of the lateral side108of the proximal portion118of the fixation plate100. The thickness of distal portion216of the anchor trajectory guide200in the medial-lateral direction is less variable. The distal portion216can have a generally constant thickness in the medial-lateral direction between the distal end of proximal portion218and the distal terminal end of the anchor trajectory guide200.

As is discussed in greater detail below, the guide apertures232are arranged to provide anchorage to cortical bone portions dispersed around the head10of the humerus H. For example, one or more, e.g., two, superior guide apertures232S can be provided to direct creation of probe channel PC and thereby anchor channels toward a superior portion of the head10. A plurality of, e.g., four, central guide apertures232C can be provided in a central portion of the proximal portion218of the anchor trajectory guide200. The central guide apertures232C can be used to form probe channel PC and thereby anchor channels for directing anchors into cortical bone regions in a central portion of the head10. Finally, a plurality of, e.g., three, inferior guide apertures232I can be provided to enable formation of probe channel PC and thereby anchor channels that are directed form the lateral surface LS of the humerus H to the medial calcar MC thereof.

FIG. 6shows that the pin aperture236can extend from the lateral side212to the medial side208along a longitudinal axis238. The longitudinal axis238preferably is non perpendicular to the lateral side212but rather is disposed at an acute angle to the lateral side212. For example, an angle of between 30 and 60 degrees, e.g., about 50 degrees can be provided between a longitudinal axis213of the lateral side212and the longitudinal axis238.

The anchor trajectory guide200also includes a locator220provided on the medial side208that can be used to couple the anchor trajectory guide200to the fixation plate100. The locator220can be configured as a protrusion with a fixed end disposed at or coupled with the medial side208and a free end disposed away from the medial side208. The free end of the locator220can be disposed medially of the medial side208. The free end of the locator220can be disposed along a longitudinal axis222of the locator220that extends through the free end of the locator and that intersects the lateral side212. The longitudinal axis222of the locator220can be disposed perpendicular to the lateral side212in one embodiment. The longitudinal axis222of the locator220can be disposed non-parallel to the longitudinal axis238. An angle of between 5 degrees and about 60 degrees, e.g., about 15 degrees, about 25 degrees or about 35 degrees can be provided between the longitudinal axis222of the locator220and the longitudinal axis238of the pin aperture236.

The locator220and the fastener aperture237can work together to secure the anchor trajectory guide200to the fixation plate100as discussed further below. For example, after the locator220is received in the locating aperture120a screw or other fastener can be advanced through the fastener aperture237and into the coupling aperture172. The coupling aperture172can be threaded to engage threads of the screw. A friction or interference fit could be used to couple the anchor trajectory guide200to the fixation plate100via the fastener aperture237and the coupling aperture172.

FIG. 3Aillustrates a anchor trajectory guide200A that is a modified example or embodiment of the anchor trajectory guide200. The anchor trajectory guide200A can include any of the features of the anchor trajectory guide200and such descriptions will not be repeated here. Also, structurally compatible features of the anchor trajectory guide200A can be incorporated into the anchor trajectory guide200. The anchor trajectory guide200A includes an perimeter along which a number of concavities are provided. The concavities include suture slots233that are disposed along an anterior side and a posterior side of the anchor trajectory guide200A. In the image, the anterior side of the anchor trajectory guide200A is generally to the left and the posterior side is generally to the right. The anchor trajectory guide200A can also include a superior suture slot233disposed at a superior location of the anchor trajectory guide200A. In one embodiment, the suture slots233align with the suture apertures164on the fixation plate100. This allows the surgeon to perform any soft tissue or bone fragment suture anchoring to the fixation plate100without interference from the anchor trajectory guide200A.

The anchor trajectory guide200A can include the guide apertures232disposed in inferior, central and superior locations as discussed above in connection with the anchor trajectory guide200. The guide apertures232can include an anterior superior guide aperture232A and a posterior superior guide aperture232B. The guide apertures232can include a plurality of, e.g., two, anterior central guide apertures232D, a plurality of, e.g., two, posterior central guide apertures232E. The guide apertures232can include an inferior guide aperture232H. The inferior terminal end of the anchor trajectory guide200can be configured to receive a portion of another guide. For example, the anchor trajectory guide200A can include a guide groove234disposed in the inferior terminal end.

One or more, e.g. all of the guide apertures232can include structures for mating with guide sleeves, which are discussed below. The guide apertures232of the anchor trajectory guide200A can include internal threads235disposed through the length of the guide apertures232. The threads235are configured such that the direction of advancing an anchor130therethrough is fixed and the threading axis is suitable for the size of the humerus being repaired. In contrast the axis of advancing the poly axial anchors130through the fixation plate100can vary. This can be made possible by any suitable structure in the polyaxial apertures134of the plate100. The threads235can retain their configuration as the anchors130are being advanced therethrough. The apertures134can allow the anchors130to be advanced in a range of directions therethrough. For example, the apertures134can have a limited number of thread features (e.g., three or less, two or less, or just one arcuate thread) from the medial to the lateral side of the plate100. Threads through the apertures134can be soft enough to allow cross-threading when the anchors130are advanced to modify an initial trajectory defined by the threads. The threads through the apertures134can comprise helical or annular arc segments that can be threaded in different directions or axes. Threads through the apertures134could also be eliminated by providing an inner surface of the apertures134that can yield as the anchor130is being advanced along a selected trajectory. These polyaxial apertures features can be imposed on the apertures134of the fixation plate100by the configuration of the threads235of the anchor trajectory guide200or the guide200A or of other variants disclosed herein. The guide apertures232can have tapered configurations, slots, or other structures for mating with the sleeves, as discussed further below.

FIGS. 7-26illustrate various fixation plate methods.FIG. 7shows that in one technique the fixation plate100is initially placed in contact with the lateral surface LS of the humerus H. A medial side112of the fixation plate100can be placed on the lateral surface LS of the humerus H. In so placing the fixation plate100, the distal portion116can be aligned with the lateral surface LS distal of the fracture F, which will usually be distal of the neck of the humerus H. Thereafter a non-locking anchor132can be placed in the slot160(seeFIG. 2) of the fixation plate100in the distal portion116. The non-locking anchor132can be placed approximately in the center of the slot160or can be guided to the center (or another initial position) by a slot anchor guide assembly239including a slot anchor guide240as shown in one embodiment inFIGS. 7A-7E. The slot anchor guide assembly239also includes a drill sleeve260. The drill sleeve260can be configured to control advancement of a drill but also can be used to couple the slot anchor guide240to the fixation plate100as discussed further below.

The slot anchor guide240includes a lateral portion242and a medial portion244. The lateral portion242is the portion that is farther away from the lateral surface LS of the humerus H when the slot anchor guide assembly239is coupled with the humerus. The medial portion244is the portion that is closer to the lateral surface LS of the humerus H when the slot anchor guide assembly239is coupled with the humerus. The lateral portion242includes an elongate cylinder246that projects between the terminal lateral end of the slot anchor guide240and the medial portion244. The elongate cylinder246can be configured with a ribbed outer surface along a portion thereof to help the surgeon grasp the slot anchor guide240.FIG. 7Fshows that in another embodiment a slot anchor guide280can be configured with a handle282as discussed further below. The lateral portion242also can include a lumen248(seeFIG. 7D) disposed therethrough. The lumen248can be accessed at a terminal lateral end of the slot anchor guide240. The lumen248can extend through the lateral portion242adjacent to the medial portion244.

The medial portion244can include a medial projection250. The medial projection250can be configured to mate with the slot160. For example, if the slot is oval shaped the medial projection250can have the same oval shape. The inferior-superior extent250L of the medial projection250can be slightly smaller than the inferior-superior extent of the slot160. As a result, the medial projection250can slip into the slot160. The slot anchor guide240is coupled with the fixation plate100using a threaded interface of the drill sleeve260, as discussed further below. In other embodiments the slot anchor guide240can be configured for positioning the fixation plate100. The medial projection250can be made to have a small amount of interference fit with the slot160so that the fixation plate100can be held on the slot anchor guide240as the surgeon moves the slot anchor guide240around. This can reduce the amount of direct handling of the fixation plate100that is needed during the procedure.

The medial portion244can also include one or more anterior-posterior projections252. The anterior-posterior projections252are configured to nest over the portions of the fixation plate100that are disposed anterior and posterior of the slot160. Although the drill sleeve260can be used to engage the slot anchor guide240to the fixation plate100by a threaded interface, in one embodiment the anterior-posterior projections252have a smaller radius of curvature than does the slot160in the anterior and posterior directions on the anterior and posterior sides of the slot160and/or mating ridges on these surfaces can be provided for the anterior-posterior projection252to grip the fixation plate100. The anterior-posterior projections252can flex to grip the fixation plate100in the area anterior and posterior of the slot160.

The slot anchor guide240also can include one or more cleats254. The cleats254provide for at least a temporary footing or connection to the lateral surface LS of the humerus H. The cleats254can be configured as short spikes that project medially of the medial projection250. The cleats254can be configured to project medially of the medial side112of the fixation plate100when the slot anchor guide assembly239is assembled. When the combination of the fixation plate100and the slot anchor guide240are brought into initial contact with the lateral surface LS of the humerus H the cleats254can be pressed into the cortical bone on the lateral surface LS which will hold the fixation plate100in place as the surgeon holds the slot anchor guide240.

The lumen248can be configured to couple with a guide sleeve, such as any of those disclosed herein. For example, the lumen248can have threads249disposed adjacent to the terminal lateral end of the lateral portion242. When a guide sleeve is disposed in the lumen248and mated with the threads249a medial end of the sleeve can be disposed adjacent to the lateral surface LS of the humerus H to provide access for a non-locking anchor132advanced through the sleeve.

As discussed above, the slot anchor guide assembly239can be coupled together using the drill sleeve260. The drill sleeve260can have a lateral portion262, a medial portion264, and a lumen268disposed through the lateral and medial portions262,264through an elongate cylinder266. The medial portion264can include a transverse projection270. The transverse projection270can include a short cylindrical shoulder that is configured to mate with a superior-inferior projection257. The transverse projection270can have a planar side that contacts a planar lateral side of the superior-inferior projection257.FIG. 7Ashows the superior-inferior projection257in a superior orientation relative to the fixation plate100. As discussed above, the anchor trajectory guide200and the anchor trajectory guide200A can be configured with a guide groove234. The guide groove234can be configured to receive the curved free end of the superior-inferior projection257so that the slot anchor guide240and the anchor trajectory guides200,200A can nest together in an assembly. The slot anchor guide240can also be oriented 180 degrees from the orientation inFIG. 7Awith the superior-inferior projection257aligned with and coupled to the inferior-most anchor aperture134. In either orientation a medial end of the drill sleeve260can be coupled to one of the anchor aperture134in the fixation plate100by way of threads disposed on an outside surface of the drill sleeve260. The medial end of the drill sleeve260can be advanced through an anchor hole258in the slot anchor guide240until threads thereon mate with threads in the anchor aperture134. Thereafter the lateral portion242and/or the lateral portion262can be used to manipulate any or all of the slot anchor guide assembly239.

FIG. 7Fillustrate a slot anchor guide assembly279that is similar to the slot anchor guide assembly239except as described differently below. The slot anchor guide assembly279includes a slot anchor guide280and the drill sleeve260. The slot anchor guide280includes a handle282. The handle282has a fixed end284that is coupled with and extends from one side of a cylindrical body in a lateral portion of the slot anchor guide280. The handle282extends longitudinally between a free end286and the fixed end284. The handle282is configured to enable the surgeon to move the slot anchor guide280and thereby the fixation plate100.

FIG. 7Fshows the slot anchor guide assembly279coupled with the fixation plate100in an opposite orientation to that ofFIG. 7A. The superior-inferior projection257of the slot anchor guide280is oriented inferiorly. The anchor hole258in the superior-inferior projection257is aligned with the distal or inferior-most anchor aperture134in the fixation plate100. Thereafter, the drill sleeve260is aligned with and advanced through the superior-anchor hole258and into the anchor aperture134. Threads on the medial portion264of the drill sleeve260are advanced into the threads in the anchor aperture134until the transverse projection270comes into contact with the lateral side of the superior-inferior projection257.

Both the superior and the inferior orientations of the slot anchor guides240,280allow the anchor trajectory guide200to be coupled with the fixation plate100at the same time as the guides240,280. The orientation ofFIG. 2Fadvantageously provides more clearance between the inferior end of the anchor trajectory guide200and the slot anchor guides240,280.

In one method the anchor trajectory guide200is coupled with the fixation plate100. For example, the medial side208of the anchor trajectory guide200can be placed up against the lateral side108of the fixation plate100. The locator220anchor trajectory guide200can be aligned with the corresponding locating aperture120of the fixation plate100and inserted into the aperture.FIG. 7shows that the profile of the medial side208is matched to the profile of the lateral side108of the fixation plate100. As such the fixation plate100can nest into the concavity of the medial side208in the proximal portion218of the anchor trajectory guide200.

Although the locator220holds the position of the anchor trajectory guide200on the fixation plate100a more complete coupling of the anchor trajectory guide200can be provided. A screw can be advanced through the fastener aperture237and into the coupling aperture172as discussed above to provide a secure connection that will persist through the procedure. In another approach, the fixation plate100can be secured by advancing a K-wire296through the pin aperture236. Because the pin aperture236and the locator220converge toward the bone and are on diverging axes away from the bone, e.g., the longitudinal axis222and the longitudinal axis238are converging toward other another toward the bone, the anchor trajectory guide200is held in place relative to the fixation plate100. The fixed position of the anchor trajectory guide200relative to the fixation plate100allows probe channel PC and corresponding anchor channels to be reliably formed in the correct locations. Prior to forming such channels, however, the location of the fixation plate100and the size of the anchor trajectory guide200can be confirmed.

FIG. 8shows that once the anchor trajectory guide200is secured to the fixation plate100and the non-locking anchor132is advanced into the bone through the slot160. The slot160advantageously allows distal-proximal motion of the fixation plate100after the non-locking anchor132is placed but before the plate is fully fixed to the humerus H. If either of the slot anchor guides240,280is used to place the fixation plate100initially such guides240,280can be removed allowing for inferior-superior adjustment of the fixation plate100relative to the lateral surface LS of the humerus H. The humeral fixation plate100A facilitates a convenient method of confirming the inferior-superior position of the humeral fixation plate100A. The K-wire296is advanced through an aperture in a guide200,200A and further through the positioning channel296A at a first position of the non-locking anchor132along the slot160A. As shown inFIG. 2Bthe non-locking anchor132can be advanced until a head portion thereof is in contact with one of the plurality of discrete position sites167, e.g., with one of the concavities167A. The K-wire296can be removed from the humerus H. The position of the humeral fixation plate100A can be evaluated. If the position is not as desired, the non-locking anchor132can be retracted sufficiently to out of engagement with the discrete position site167in which it was initially positioned. The humeral fixation plate100A can be shifted relative to the non-locking anchor132to a plurality of discrete position sites167proximal or distal of the initial site, e.g., to a concavity167A proximal or distal to the initial concavity. The non-locking anchor132can be advanced into the concavity167A at the new position. Then, the K-wire296can be advanced through the guide200,200A into the humerus H through the positioning channel296A. The spacing between two adjacent concavities of the concavities167A can be enough to assure that the K-wire296is not in the same position, e.g., in the channel that was formed in the humerus H in the first insertion. For example, the spacing between plurality of discrete position sites167can be one-half the diameter of the K-wire296, e.g., about 1 mm in one embodiment. In other embodiment, the spacing is less or greater. For example, the spacing can be about 2 mm, about 3 mm or about 4 mm in various modified embodiments. The visual spacing indicator169, e.g., the lines171, can be positioned at each or at alternating concavities167A. The spacing indicator169, e.g., the lines171, can be at greater intervals, e.g., every third or fourth concavity. In one method, after advancing the K-wire296through the aperture positioning channel296A at a first position of the slot160A relative to the anchor non-locking anchor132, the K-wire is removed from the humerus H. The position of the humeral fixation plate100A is shifted proximally or distally (e.g., inferiorly or superiorly) to a second position of the slot relative to the anchor132. The second position is spaced from the first position by an amount greater than the one-half of or the diameter of the K-wire296. The second position is provided by advancing the non-locking anchor132into a discrete position site of the plurality of discrete position sites167spaced along the slot160A from the initial site of the plurality of discrete position sites167. The slot160A enables the non-locking anchor132to be retracted out to the concavities167A without having to remove the non-locking anchor132from the humerus H when shifting among these and other positions that are defined along the slot160A.

The plurality of discrete position sites167and the visual spacing indicator169enhance the usefulness of the humeral fixation plate100A by allowing the surgeon to be certain that second and subsequent positions are spaced apart from an initial position. By providing this guidance, the surgeon can more quickly, accurately and confidently proceed through the stages of methods involving the humeral fixation plate100A.

If the inferior-superior position is initially confirmed, K-wires can be advanced into the head10of the humerus H. A first K-wire296can be advanced toward the medial calcar MC region. Thereafter the appropriate size anchor trajectory guide200can be confirmed by advancing a second K-wire296into a superior anterior guide aperture232S. With these K-wires296placed, the size of the anchor trajectory guide200can be confirmed. For example, if the proximal end of the anchor trajectory guide200is a prescribed distance, e.g., 10 mm, from a proximal aspect of the head10then the size of the anchor trajectory guide200is appropriate. The proximal aspect from which the distance to the anchor trajectory guide200is measured can be the greater tuberosity GT. If the proximal end of the anchor trajectory guide200is less than about 10 mm from the proximal aspect of the head10then a smaller anchor trajectory guide200can be selected. If the proximal end of the anchor trajectory guide200is more than about 10 mm from the proximal aspect of the head10then a larger anchor trajectory guide200can be selected.

In another embodiment, the size of the head10of the humerus H can be estimated by providing a scale on a K-wire296to be inserted into the pin aperture236in the center of the anchor trajectory guide200after the non-locking anchor132has secured the fixation plate100to the humerus H. The trajectory of the K-wire296is aligned with the center of the articular surface of the head10. The scale can include markings that indicate the length of the K-wire296inserted into pin aperture236, across the cancellous portion of the head10into contact with the cortical bone region CB. From this dimension, the size of the anchor trajectory guide200to be used can be determined. In some cases the K-wire296can indicate a size (small, medium, large, etc.) of the anchor trajectory guide200to be used. The K-wire296can indicate both a dimension and a size in some embodiments.

After the size and placement of the anchor trajectory guide200are confirmed the fixation plate100can be secured to the humerus H to prevent movement therebetween.FIG. 9shows that securing the fixation plate100to the humerus H can be achieved by inserting a polyaxial anchor130into an anchor aperture134in the distal portion116of the fixation plate100. The method can then proceed to forming probe channels PC and thereafter to implanting anchors as discussed further below.

FIGS. 8-18show that guide sleeves can be used in the formation of an inferior probe channel PC. A sleeve300can be mated to the anchor trajectory guide200. In one technique, a medial end of the sleeve300can be inserted into one of the inferior guide apertures232I and advanced from the lateral side212toward the medial side208of the anchor trajectory guide200. The sleeve300can be seated in the anchor trajectory guide200by engaging threads on the outside surface of the sleeve300with internal threads in the inferior guide aperture232I. For example, the anchor trajectory guide200can have, as illustrated above inFIG. 3Ain connection with the anchor trajectory guide200A, internal threads235disposed in an anterior inferior guide aperture232F and in a posterior inferior guide aperture232G that can be engaged by threads on the exterior surface of the sleeve300. In other embodiments the sleeve300can be mated with a slip fit inside the inferior guide aperture232I or any of the other guide apertures232. Once the sleeve300is seated it can be an outer sleeve to receive other structures and devices. An inner sleeve320can be inserted into the sleeve300. The inner sleeve320can be inserted by advancing a medial end of the inner sleeve320into a lateral end of the sleeve300until flanges or hubs300a,320aat the lateral ends of the sleeve300and of the inner sleeve320are coupled, e.g., are adjacent to or abutting each other. The inner sleeve320can be seated in or mated to the sleeve300by engaging threads on an outside surface of the inner sleeve320with internal thread disposed in the inside of the sleeve300. The inner sleeve320can be configured to direct a K-wire296through the anchor trajectory guide200along a guide axis that is pre-defined to an axis in the humerus H to begin the formation of the probe channel PC in a desired location as shown inFIG. 8. The inner sleeve320can have an inner diameter that is closely matched to an outer diameter of the K-wire296such that the trajectory of the K-wire296is controlled by the location and orientation of the inferior guide aperture232I indirectly, which controls the position and orientation of the sleeves300,320.

After the inner sleeve320has been mated with the sleeve300and the sleeve300has been mated with the anchor trajectory guide200the K-wire296can be advanced into the humerus H through the cortical bone at the lateral surface LS and into the cancellous bone within the cortical bone. The trajectory of the K-wire296is pre-defined by the location and orientation of the mating of the fixation plate100with the humerus H and by the orientation of the guide apertures232as described above. Advancing the K-wire296into the humerus H defines the direction along with the probe channel PC will be formed.

FIG. 8also shows a K-wire296can be inserted into a superior portion of the head10of the humerus H through the superior guide apertures232S. Inserting the K-wire296through the superior guide apertures232S can include mating sleeve300with the superior guide apertures232S and inserting the inner sleeve320into the sleeve300. For example, the anchor trajectory guide200can have, as illustrated above inFIG. 3Ain connection with the anchor trajectory guide200A, internal threads235disposed in an anterior superior guide aperture232A and a posterior superior guide aperture232B that can be engaged by threads on the exterior surface of the sleeve300. As noted above the position of the fixation plate100and the anchor trajectory guide200are confirmed following insertion of the inferior and superior guide apertures. If the position is confirmed insertion of the K-wires296through the superior guide apertures232S defines the trajectory of the probe channel PC to be formed later the procedure.

FIG. 9shows that in some techniques the fixation plate100is secured to the humerus H by inserting the polyaxial anchor130through the fixation plate100as discussed above. The distal portion116can include a polyaxial aperture134disposed distally of the slot160. The polyaxial aperture104at this location is advantageous for providing enhanced security of the fixation plate100because it is farthest from the proximal portion118through which one or a plurality, e.g., two as illustrated inFIG. 9, K-wires296can be advanced.FIGS. 2 and 9shows a configuration in which the non-locking anchor132is fully advanced in the slot160(SeeFIG. 2) and the polyaxial anchor130is fully advanced into the distal polyaxial aperture134to immobilize the fixation plate100against the lateral surface LS of the humerus H.

FIGS. 10-16Aillustrate additional approaches to orient the anchor trajectory guide200and the fixation plate100on the humerus H.FIG. 10shows an anatomical alignment guide400that can be mated to the anchor trajectory guide200. The anatomical alignment guide400can include a sleeve404that is configured to mate with one of the guide apertures232, e.g., one of the inferior guide apertures232I. The sleeve404includes a lumen408that extends from a lateral side of the sleeve404, e.g., from a flange or hub406, to a medial side thereof. The lumen408is configured to slideably receive a K-wire296as discussed below. The anatomical alignment guide400also includes a visual alignment member412disposed away from the sleeve404. The visual alignment member412can include an arcuate member418that is coupled at a first end with a lateral end of the sleeve404. The arcuate member418can extend in a first portion418A away from the sleeve404, e.g., in a direction substantially perpendicular to the orientation of the lumen408. The first portion418A can extend sufficiently from the sleeve404to provide clearance between the head10of the humerus H and a second portion418B of the arcuate member418that extends from the first portion418B when the anchor trajectory guide200is coupled with the fixation plate100and thereby with the lateral surface LS of the humerus H. The second portion418B can be substantially parallel to the sleeve404in one embodiment. The arcuate member418is configured in the second portion418B to extend sufficiently to be positioned or aligned with, e.g., in front of, pre-defined anatomy to which the K-wire296disposed through the sleeve404is to be aligned. As discussed further below, the arcuate member418is configured to extend away from the sleeve404to a position in front of (either on the anterior or posterior side of the humerus H) so as to be between the surgeon's eye and the an anatomical landmark. Thus the arcuate member418can provide a visual alignment device for visually aligning the anatomical alignment guide400with the landmark. When so aligned the surgeon knows that a K-wire296placed through the lumen408and through the inferior guide apertures232I extends in a direction toward the landmark, e.g., toward the medial calcar.FIGS. 13-16Aillustrate this method with the anatomic alignment guide400and with an anatomic alignment guide400A discussed further below. The guide400A is similar to the guide400except as described differently below.

In the flow of the methods discussed above,FIGS. 13 and 14are alterative techniques to that shown inFIGS. 7-9.FIG. 13shows the fixation plate100mated with the lateral surface LS of the humerus H. The anchor trajectory guide200A is mated with the lateral side108of the fixation plate100. The anchor trajectory guide200could be used, as is illustrated in some of the figures. One K-wire296is placed through the pin aperture236into the head10of the humerus H. The anatomical alignment guide400A is mated with the anchor trajectory guide200A. For example, the sleeve404can be inserted into the inferior guide aperture232H. In one example, the connection between the sleeve404and the inferior guide aperture232H can be a slip fit, although other connections are possible as well. The fixation plate100can be mated to the humerus H by the non-locking anchor132inserted into the slot160, which permits the fixation plate100to be moved proximally and distally on the humerus H. The movement of the fixation plate100can be until the anatomical alignment guide400A is aligned with a predefined anatomical landmark, such as the medial calcar MC. Aligning the anatomical alignment guide400A with the medial calcar MC can include viewing the anterior surface of the head10of the humerus H head on and moving the assembled fixation plate100, anchor trajectory guide200A, and anatomical alignment guide400proximally or distally until the second portion418B of the arcuate member418is aligned with the medial calcar MC. In the case of the guide400A, the guide400A can be moved proximally and distally until a K-wire422is aligned to the medial calcar MC

Following alignment of the arcuate member418or the K-wire422with the medial calcar MC one or both of the K-wires296can be placed through the anchor trajectory guide200or the guide200A. A superior K-wire296can be placed through the pin aperture236in the anchor trajectory guide200or the guide200A. An inferior K-wire296can be placed through the inferior guide aperture232I to which the anatomical alignment guide400or the guide400A is mated. The K-wire296can be inserted through the sleeve404or through the inner sleeve320disposed in the sleeve404. As illustrated above inFIG. 3Athe anchor trajectory guide200A shows that anterior inferior guide aperture232F and the posterior inferior guide aperture232G have internal threads235disposed therein that can be engaged by threads on the exterior surface of the inner sleeve320. In some embodiments, the size of the anchor trajectory guide200or the guide200A is confirmed by measuring a distance from a proximal landmark such as the greater tuberosity to the proximal edge of the anchor trajectory guide200or the guide200A. A distance of about 10 mm indicates proper sizing of the anchor trajectory guide200or the guide200A. A smaller distance between the proximal landmark and the proximal edge of the anchor trajectory guide200or the guide200A suggests a smaller humerus for which a smaller anchor trajectory guide200or guide200A is appropriate. A larger distance between the proximal landmark and the proximal edge of the anchor trajectory guide200or the guide200A suggests a larger humerus for which a larger anchor trajectory guide200or guide200A is appropriate.

Other methods of sizing the anchor trajectory guide200or guide200A can include placing K-wires296in an inferior guide aperture232I and in a superior guide aperture232S. When the K-wire296is properly placed using the anatomical alignment guide400or the guide400A, e.g., extending to the medial calcar MC the position of the K-wire296in the inferior guide aperture232I can be confirmed to not be too far proximally suggesting that the anchor trajectory guide200or the guide200A is too large and not too far distally suggesting that the anchor trajectory guide200or the guide200A is too small. As noted above, the size of the humerus H can also be assessed by the depth into the head10that a K-wire296inserted into the pin aperture236extends. Other methods for sizing the anchor trajectory guide200or guide200A can include measuring an external dimension of the head10of the humerus H or analyzing imaging data (pre-operative or intra-operative).

FIG. 16shows an alternate method in which after the K-wires296have been placed a polyaxial anchor130can be advanced through the fixation plate100through the guide aperture232disposed in the distal portion216of the anchor trajectory guide200or guide200A. The combination of the polyaxial anchor130and the non-locking anchor132in the slot160secures the fixation plate100to the lateral surface LS of the humerus H. This provides a fully secure position for the remaining portions of the procedure. After the fixation plate100is fixed to the lateral surface LS distal of the fracture F, a first polyaxial anchor130can be secured to the head10of the humerus H through the anatomical alignment guide400as shown inFIG. 16Aor through the guide400A. Placing the polyaxial anchor130through the anatomical alignment guide400or the guide400A can be directly into the small channel formed by the K-wire296or can be following further bone preparation discussed below. If a polyaxial anchor130is placed through the anatomical alignment guide400or the guide400A, following such placement the anatomical alignment guide400or guide400A can be removed from the anchor trajectory guide200or the guide200A.

FIGS. 10 and 16Ashow that one variation of the anatomical alignment guide400provides a secondary sleeve426in addition to the arcuate member418. The secondary sleeve426is disposed between the sleeve404and the arcuate member418. Like the arcuate member418, the secondary sleeve426is disposed anteriorly of the anterior face of the humerus H when the sleeve404is mated with the inferior guide aperture232I. In being so placed, the secondary sleeve426can receive a K-wire296which can slide medially until the K-wire296is in front of a relevant landmark, e.g., the medial calcar. The secondary sleeve426can be used when the arcuate member418is not in a good position for visualizing the landmark of interest. In some variations, the secondary sleeve426and the arcuate member418extend along planes or longitudinal axes that are not aligned. This enables the arcuate member418to be configured to visually align with one anatomical landmark, e.g., the medial calcar MC, and the secondary sleeve426to be configured to visually align with a different anatomical landmark.

FIGS. 11 and 12illustrate the anatomical alignment guide400A in more detail. The anatomical alignment guide400A is a streamlined form of visual alignment aid. The anatomical alignment guide400A has a sleeve404as is described above. Coupled with and disposed to the side of the sleeve404is a secondary sleeve426. The secondary sleeve426is located at a free end of a transverse projection428of the anatomical alignment guide400A. The transverse projection428can have a first end couple with the sleeve404and a second end disposed away from the sleeve404and coupled with the secondary sleeve426. The secondary sleeve426can be disposed to the side of (and in use generally anteriorly of) the sleeve404and at the end of the free end of the transverse projection428.FIG. 12shows that the secondary sleeve426of the anatomical alignment guide400A is disposed entirely to the side of the medial side208of the anchor trajectory guide200. This allows the secondary sleeve426to be medial of the fixation plate100and of the lateral surface LS of the humerus H when applied to the patient. This allows the anatomical alignment guide400A to be out of the field of view of the head10of the humerus H during portions of the method, as illustrated byFIG. 13. The anatomical alignment guide400A is thus lower profile than the anatomical alignment guide400so that the anatomical alignment guide400A is less obstructive when mated with the lateral surface LS of the humerus H by way of the anchor trajectory guide200and the fixation plate100.

The secondary sleeve426of the anatomical alignment guide400A is configured to be coupled with a wire422. The wire422can be inserted through a lumen in the secondary sleeve426. Preferably the transverse projection428is long enough that when the sleeve404is mated with the inferior guide apertures232I the wire422can be inserted through the secondary sleeve426at a location spaced anterior of an anterior side or posterior of a posterior side of the head10of the humerus H. Thus, the wire422can be advanced through the secondary sleeve426without entering the humerus H but rather being disposed away from and along-side the bone.

In use, the wire422can be inserted into the secondary sleeve426along-side the head10of the humerus H, as shown inFIGS. 13-16. The fixation plate100and the anchor trajectory guide200can be aligned to the bone (e.g., by sliding slot160along the non-locking anchor132) until the wire422is aligned with a selected anatomical landmark or locations, such as with the medial calcar MC (seeFIGS. 13-16). The transverse projection428is configured such that the sleeve404and the secondary sleeve426are aligned and the longitudinal axes of the lumens formed therethrough also are aligned. As such, the K-wire296can be inserted into the sleeve404and into the lateral surface LS of the humerus H with confidence that the K-wire296will be directed to the medial calcar MC when the wire422is directed along the side of the head10of the humerus H toward the medial calcar MC.

The anatomical alignment guide400A also provides a simple visual confirmation at least on the anterior side thereof. A lateral length of the wire422should cover up and prevent a viewer from seeing a lateral length of the K-wire296disposed through the lumen408of the sleeve404when the alignment of the fixation plate100and anchor trajectory guide200A or200is proper, as seen in comparingFIGS. 13 and 14. In other words, a viewer seeing the wire422head-on should only see one wire and should not see the K-wire296disposed immediately posterior or behind the wire422.

The anatomical alignment guides400,400A provide convenient way to confirm the fixation plate100is properly aligned to the lateral surface LS of the humerus H can be fully secured by inserting the polyaxial anchor130into the distal guide aperture232.

FIGS. 17 and 17Ashow a portion of a method that can follow any of the alignment techniques discussed above to form the probe channels PC through the properly sized anchor trajectory guide200or guide200A. In one step, the inner sleeve320disposed in the inferior guide aperture232I can be exchanged for an inner sleeve340that is configured to receive a drill bit344. In some cases, the drill bit344can be configured with the same diameter as the K-wire296so this exchange is not necessary in all cases. In many circumstances, the drill bit344has a larger diameter than the diameter of the K-wire296. In some instances, the drill bit344can be directly inserted into the sleeve300such that the inner sleeve320configured for the K-wire296can simply be removed and the drill bit344can be advanced directly through the sleeve300. Where the inner sleeve340configured for the drill bit344is needed, the inner sleeve340can be advanced such that the medial end thereof is advanced into an aperture at the lateral end of the sleeve300. The inner sleeve340can be docked with the sleeve300in any suitable manner, e.g., using a threaded connection, slip fit or friction fit. Thereafter, the drill bit344can be advanced into the humerus H through the lateral surface LS thereof as shown inFIG. 17A. The drill bit344can have a smooth and tapered tip that can be configured to initially enter the lateral surface LS enlarging the hole therethrough formed by the K-wire296. A length of the drill bit344between the tapered tip and the opposite end of the drill bit344can be threaded to enlarge the small passage formed by the K-wire296between the lateral surface LS and the cortical bone region CB opposite the lateral surface LS on the medial side of the head10in some techniques. In other embodiments the drill bit344is used to enlarge the opening through the lateral surface LS of the humerus H but not to enlarge the passage formed by the K-wire296all the way to the cortical bone region CB.

FIGS. 18 and 19show that after the drill bit344is removed the inner sleeve340can be exchanged for a probe360. The probe360can be configured to perform multiple functions. The probe360can provides a basis for choosing an appropriate polyaxial anchor130from a plurality of anchors, e.g., for choosing the polyaxial anchor130that has a length that will result in a medial portion of the polyaxial anchor130being embedded in the cortical bone region CB and a lateral portion of the polyaxial anchor130engaging one of the locating apertures120of the fixation plate100.FIG. 18shows that the probe360can be inserted into the lateral end of the sleeve300and the probe360can dock with the sleeve300. When the probe360is docked with the sleeve300, an inner member of the probe360can be inserted all the way across the head10to the cortical bone region CB. At that point, the indicia362at the lateral end of the probe360indicate which of the polyaxial anchor130is suitable for the particular locating aperture120.

Another function of the probe360can be to enlarge the channel formed by the K-wire296from the lateral surface LS of the humerus H to the cortical bone region CB to fully form the probe channel PC.FIG. 19shows that a blunt tip361can be provided that is well suited for pushing through the cancellous bone matter within the head10of the humerus H to formed the probe channel PC. The blunt tip361preferably is rounded to displace but not attach to tissue that is engaged thereby.

FIGS. 20-21show one embodiment of the probe360in more detail. The probe360includes an outer member364and an inner member365. The outer member364includes a medial portion366and a lateral portion368. The medial portion366includes a slender cylindrical portion with a lumen formed therein. The lateral portion368includes an outer surface that can have ribs for gripping by the surgeon and an inner lumen formed therein. A shoulder370can be formed between the medial portion366and the lateral portion368. The shoulder370can be used in docking the probe360to the sleeve300. For example, the probe360can be inserted into the sleeve300until the shoulder370abuts a lateral surface of the probe360. The lateral portion368can have an aperture372at a lateral end thereof.

The inner member365can have a cylindrical medial portion374and a graduated lateral portion376. The cylindrical medial portion374can be configured to slide within the lumen of the medial portion366. The cylindrical medial portion374can be rigid to push cancellous matter aside to form the probe channel PC in some embodiments and can be configured with the blunt (e.g. rounded) tip361that can be atraumatic (e.g., configured not to hook or otherwise attach to bone matter). The tip361is configured to be inserted into the bone to enlarge the channel formed by the K-wire296to form the probe channel PC. When the tip361contacts the cortical bone region CB opposite the lateral surface LS the probe channel PC has been formed. The graduated lateral portion376can be configured to move into or out of the lateral portion368of the probe360. The graduated lateral portion376can include the indicia362formed along a side surface thereof. The indicia362can include numbers indicating the length of the medial portion374spanning the cancellous bone to the cortical bone region CB. The same length can inform the choice of a polyaxial anchor130to be used in the particular probe channel PC. The indicia362can include any other marking that conveys to the surgeon which of a plurality of different length polyaxial anchor130to select (e.g., small, medium, and large).

FIG. 22shows that in a technique after the size of the polyaxial anchor130to be used is selected, the appropriately sized polyaxial anchor130can be inserted into the sleeve300and advanced into the probe channel PC through one of the inferior guide apertures232I. After the polyaxial anchor130is fully inserted the medial tip of the polyaxial anchor130is lodged in the opposing cortical bone region CB and the lateral end is engaged with one of the distal locating apertures120of the fixation plate100, as shown inFIG. 23. Using the probe360ensures that the medial end of the polyaxial anchor130when fully advanced does not breach the cortical bone on the medial side of the humerus H, e.g., is not exposed on the articular surface of the humerus H. This is important because it prevents the polyaxial anchor130from contacting the articular surface at or on the glenoid of the scapula as discussed above.

FIG. 23also shows that a technique can continue with using the drill bit344to facilitate enlarging an opening through the lateral surface LS of the humerus H formed by a K-wire296to enable the probe360to be used to aid in selection of an appropriately sized polyaxial anchor130and/or to form a probe channel PC through the head10of the humerus H. The drill bit344is advanced through the superior guide apertures232S guided by the sleeve300and the inner sleeve320.

FIGS. 24 and 25show that the processes of forming and probing the probe channels PC and selecting appropriate sized polyaxial anchors130and thereafter inserting the polyaxial anchor130into the humerus H can be continued until a sufficient number of polyaxial anchor130are implanted, e.g., more than half of the anchor aperture134and some cases all of the anchor aperture134have a polyaxial anchor130secured therein. Thereafter the anchor trajectory guide200can be undocked form the lateral side108of the fixation plate100. In one embodiment, a screw is removed from coupling aperture172and the fastener aperture237and the locator220can be removed from the locating aperture120to permit the anchor trajectory guide200to be removed from the fixation plate100.

FIG. 26shows that in some techniques at least one of the polyaxial anchors130can be implanted after the anchor trajectory guide200is removed. In one technique a polyaxial anchor130can be implanted on the distal side of the neck of the humerus H, e.g., distal of the fracture F without any guidance from the anchor trajectory guide200.

FIG. 27shows that in some techniques a great deal of splaying is provided among the polyaxial anchor130. For example, some, more or all of the polyaxial anchor(s)130on an anterior side of the medial-lateral and proximal-distal plane PL can be oriented to diverge from the medial-lateral and proximal-distal plane PL at their medial tips. Some, more or all of the polyaxial anchor130on a posterior side of the medial-lateral and proximal-distal plane PL can be oriented to diverge from the medial-lateral and proximal-distal plane PL at their medial tips. Providing at least some splaying creates excellent security and force spreading to assure strong connection of the fixation plate100to bone portions located proximal and distal of the fracture F. Greater splaying also assures that the medial end142of the non-locking anchor132will be outside of or around the periphery of the articular surface of the head10. This peripheral positioning of the medial end142provides an enhanced degree of safety for the patient.

As discussed above the anchor trajectory guide200can be provided in a range of sizes. For example, the anchor trajectory guide200can have a small size, a medium size, and a large size. The large size anchor trajectory guide200can provide a greater amount of splaying than illustrated inFIG. 27such that the polyaxial anchor tips are secured in the cortical bone. In the larger size the medial ends142can be disposed outside of a boundary500that is more anterior on one of the medial-lateral and proximal-distal plane PL and more posterior on the opposite side of the medial-lateral and proximal-distal plane PL than is the illustrated by the medial ends142shown inFIG. 27. The smaller size anchor trajectory guide200can provide a lesser amount of splaying than illustrated inFIG. 27. In the smaller size, the medial ends142will be disposed inside a boundary504that is less anterior on one of the medial-lateral and proximal-distal plane PL and less posterior on the opposite side of the medial-lateral and proximal-distal plane PL than is the illustrated by the medial ends142shown inFIG. 27. Of course the bone will also be smaller for patient for which the boundary504is appropriate. As such the location of the medial ends142will generally stay peripheral of the articular surface of the humerus H regardless of the size of the anchor trajectory guide200. The polyaxial anchor130enable the same fixation plate100to be used with a range of sizes, including enabling the medial end142to reach the position shown or either one of the boundaries500,504. This advantageously simplifies the number of kits and the inventory needed to provide great outcomes for a wide range, if not the entire population, of patients. As discussed above the anchor trajectory guide200can be patient specific to provide the maximal amount of splaying possible in the bone of the specific patient or to target maximal amount of splaying into good bone and minimize splaying into weakened bone. In that case, the amount of splaying is specific to the patient and can be different for each anchor aperture134and for each polyaxial anchor130.

FIG. 28shows an example of a kit550that can be provided in some embodiments. The kit550includes a plurality of anchor trajectory guides200. Each of the anchor trajectory guide200can include a different size. For example, one of the anchor trajectory guide200can be suitable for an average size humerus, one of the anchor trajectory guide200can be suitable for larger humerus sizes, and one can be suitable for smaller humerus sizes. The periphery of the anchor trajectory guide200are generally not different, but the locations, positions, orientations, and/or trajectories of the guide apertures232through the anchor trajectory guide200will be different to assure the medial end142are splayed to an appropriate degree. The kit550can also include the fixation plate100. The kit550also can include the humeral fixation plate100A. The kit550also can include a tuberosity fracture plate600discussed further below. Further, the kit550can include a plurality of polyaxial anchor130. The polyaxial anchor130will be provided in a range of sizes to facilitate the above methods which provide the distal (medial) tips of the anchors to be lodged in opposing cortical bone but not breaching the opposite (medial) side of the humerus while the proximal (lateral) ends of the polyaxial anchor130are engaged with the lateral side108of the fixation plate100. This requires a range of sizes for the polyaxial anchor130disposed in the neck region and in various regions of the head10portion of the humerus H, as indicated by the probe360. The kit550can also include one or a plurality of non-locking anchor132configured for engaging the slot160of the fixation plate100. The kit550can also include a plurality of surgical tools, including K-wires296, outer sleeves300, inner K-wire sleeves320, inner probe and screw sleeves340, and probe360. The kit550can comprise a kit of implantable components and a kit of surgical components.

IV. Tuberosity Plates and Methods

FIGS. 1B, 1C, and 29-30Dillustrate a tuberosity fracture plate600and the use thereof to repair a tuberosity fracture TF in the humerus. The tuberosity fracture plate600includes a tuberosity end604and a distal portion608. A distance between the tuberosity end604and the opposite end of the distal portion608can be between about 40 mm and about 70 mm, e.g., between 45 mm and 65 mm. The distance between the tuberosity end604and the opposite end of the distal portion608can be between 50 mm and 60 mm, e g., about 53 mm. The tuberosity end604includes a first portion612and a second portion616. The first portion612can be a portion that will overlay a first tuberosity, e.g., a greater tuberosity GT. The first portion612can be used to secure one side of a fractured first tuberosity GT to the rest of the humerus H. The second portion616can be used to secure the other side of a fractured first tuberosity GT to the rest of the humerus H.

The first portion612can be used to secure one side of a second tuberosity, e.g., a lesser tuberosity LT to the rest of the humerus H. The second portion616can be used to secure the other side of a fractured second tuberosity LT to the rest of the humerus H. A distance between a portion of the first portion612disposed opposite the longitudinal axis648and a portion of the second portion616disposed opposite the longitudinal axis648can be between about 15 mm and about 45 mm, e.g., between about 20 mm and about 40 mm. In some cases, a distance between a portion of the first portion612disposed opposite the longitudinal axis648and a portion of the second portion616disposed opposite the longitudinal axis648can be between about 25 mm and about 35 mm, e.g., about 29 mm.

The first portion612and the second portion616can both be used to secure a greater tuberosity, e.g., the first portion612can be used on a left humerus H to secure the greater tuberosity GT and the second portion616can be used on a right humerus H to secure the greater tuberosity GT of the right arm.

The tuberosity fracture plate600can have a plurality of screw holes. For instance, a first screw hole624can be provided on the tuberosity end604. The first screw hole624can be disposed in the first portion612to hold a polyaxial screw130to secure a first tuberosity GT. A second screw hole628can be provided on the tuberosity fracture plate600. For example the second screw hole628can be provided on the distal portion608. The second screw hole628also can engage a polyaxial screw130to secure the tuberosity fracture plate600to the humerus H, e.g., to a portion of the humerus H not on fractured fragment, e.g., the fragment including the first tuberosity GT. The tuberosity fracture plate600can include additional screw holes, e.g., a screw hole640can be provided in the distal portion608. A plurality of screw holes640can be provided in the distal portion608. A screw hole644can be provided in the tuberosity end604. A plurality of screw holes644can be provided in the tuberosity end604. The screw hole or holes644can be disposed away from the first screw hole624. The screw hole644can secure a portion of the humeral head when the first screw hole624is secured to the fractured and fragmented first tuberosity GT. Usually all of the screw holes624,644, will be engaged with a screw130.FIG. 299shows that screws130can be placed in each of the screw holes of the plate600.FIG. 30Ashows that the plate600can have a relief625formed in the screw holes624,644that are off-set from the longitudinal axis648. The relief625is formed to allow the screw130be inserted into the plate600along a trajectory that is perpendicular to a plane tangent to the lateral side of the plate600at the longitudinal axis648. The relief625can enable a screw139to be disposed along a trajectory that is parallel to the trajectory of one or more screws130disposed through the screw holes that are on the longitudinal axis648, e.g., extending perpendicular to the axis648through the holes640. In other techniques the first screw hole624is used to secure the fragmented portion of the humerus H, e.g., the first tuberosity GT and the screw hole or holes644is left without any screws in it to minimize the invasiveness of the procedure in the humerus H.

The tuberosity fracture plate600can include a bend zone632disposed along the length there. The bend zone632can be a portion that is configured to preferentially bend. For example, when a load is applied to the ends of the tuberosity fracture plate600the plate bend in the bend zone632. In one embodiment a bend zone632is provided between the tuberosity end604and the distal portion608. In one embodiment, a plurality of bend zones632are provided along the length of the tuberosity fracture plate600. A bend zone632can be provided between each pair of a plurality of adjacent screw holes640. The bend zone632enable a plate that initially disposed along a straight longitudinal axis648to be shaped to match the shape of the lateral side of the humerus H. The shaped form of the tuberosity fracture plate600can be adjusted from straight along the longitudinal axis648to one or a plurality of curves along the length from the proximal to the distal end of the tuberosity fracture plate600.

The bend zone632can be formed in any suitable way. For example, the tuberosity fracture plate600can have a portion with a first thickness654at one or all of the screw hole640and a second thickness656in the bend zone632. The second thickness656can be less than the first thickness654. The second thickness656can be less than 50% of the thickness of the tuberosity fracture plate600outside the bend zone632. The thickness656can be between 0.5 mm and 1.5 mm, e g., about 1 mm in various embodiments. The thickness656can be between 0.5 mm and 1.5 mm, e.g., about 1 mm Without the bend zone632the location of the screw hole640would be the location most likely to localize bending. The location of the screw hole640would correspond to a bending location. However, because the bend zone632has a second thickness656that is less than the first thickness654the bending of the tuberosity fracture plate600is focused at the bend zone632. The second thickness656can be one-half or less than the first thickness654. The second thickness656can be about one-half the first thickness654. The second thickness656can be about one-third the first thickness654. The second thickness656can be about one-quarter the first thickness654.

FIG. 30Cshows that the tuberosity fracture plate600can be pre-formed with transverse curvature. The tuberosity fracture plate600can be curved in the tuberosity end604transverse to the longitudinal axis648. The tuberosity fracture plate600can be curved in the distal portion608transverse to the longitudinal axis648.

FIG. 30Dshows that one or more of the first screw hole624, the second screw hole628, the screw holes640, and the screw hole644can be threaded. The threaded holes624,628,640,644can be configured to receive polyaxial screw130. The threaded holes624,628,640,644can thus enable the polyaxial screw130to be targeted to safe anatomy of the humerus H, e.g., away from the articular surface thereof.

FIG. 29illustrates the method of securing a fracture of a first, e.g., a greater tuberosity GT. The first tuberosity GT is brought into place on the remainder of the humerus H. The tuberosity fracture plate600is placed over the humerus H and the first tuberosity GT. A polyaxial screw130is advanced through the first screw hole624and into the first tuberosity GT. One or more, e.g., all of the screw hole640receive a polyaxial screw130. Prior to placing some or all of the polyaxial screw130the tuberosity fracture plate600can be shaped to match the shape of the humerus H. The tuberosity fracture plate600can be bent along one or more of the bend zones632to create curvature along the longitudinal axis648that matches that of the particular patient's humerus H. The tuberosity fracture plate600can be fully secured to the one once shaped. In some methods, gross shaping is performed by the surgeon. The very act of advancing the polyaxial screw130into the tuberosity fracture plate600can cause additional bending to further match the tuberosity fracture plate600to the shape of the humerus H of the patient.

The tuberosity fracture plate600can have one or a plurality of suture apertures652. The plurality of suture apertures652can receive a suture to secure one or more bone fragment to the tuberosity fracture plate600. For example, in some cases the first tuberosity GT is too fragmented to allow the polyaxial screw130to secure the first tuberosity GT to the tuberosity fracture plate600. In that case, one or more sutures can secure the fragment(s) of the first tuberosity GT to the tuberosity fracture plate600and/or to the rest of the humerus H.

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.

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.

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.”