INTRAOPERATIVE CUSTOM VOID FILLING METHODS, SYSTEMS AND APPARATUSES

Methods, systems and apparatuses for treating a defect in a bone that forms at least a portion of a joint of a patient are disclosed. According to one example, a system including a first prosthesis, a second prosthesis and an alignment guide is disclosed. The first prosthesis can comprise a formable material. The second prosthesis can have a stock construction and can be configured to be implanted in the joint on at least a portion of the first prosthesis once the first prosthesis is formed to take a shape of and substantially fill a volume of the defect. The alignment guide can be configured to couple to the second prosthesis to retain the second prosthesis in a desired position and a desired orientation in the joint on the at least the portion of the first prosthesis.

FIELD

The present subject matter relates to an orthopedic devices, systems and methods, and specifically to combinations of devices that can be used to treat a defect in a patient's anatomy.

BACKGROUND

In a healthy shoulder, the proximal humerus is generally ball-shaped, and articulates within a socket formed by the scapula, called the glenoid, to form the shoulder joint.

Patients may require joint repair in various anatomical areas to restore natural joint movement and reduce pain. Shoulder joint reconstruction may require repairing a defect in a shoulder joint such as a void in the glenoid resulting from severe wear.

Current methods for reconstructing the shoulder joint are sometimes not sufficiently accurate to reproduce the natural joint movement of the shoulder joint such as glenoid version without excessive time, trial and/or expense. One of the challenges when installing an implant in the glenoid relates to the positioning of the implant. Due to the presence of soft tissue such as ligaments, the positioning of the implant must be planned to replicate as much as possible the normal bio-mechanical movements of the humerus relative to the scapula. For patients with severe joint damage (e.g. as a result of a defect), obtaining a desired placement and orientation of the implant can be even more challenging.

Considering these and other challenges, patient specific implants and instrumentation (hereinafter “PSI”) has been used in some cases. PSI pertains to the creation of implants and instruments that are made specifically for the individual patient. PSI are typically manufactured from data using imagery to model bone geometry. Therefore, PSI have surfaces that may contact the bone in a predictable way as such contact surfaces are specifically manufactured to match the surface of a bone. It would be desirable to use PSI technology in shoulder surgery. However, PSI can be cost prohibitive, complex and/or too time consuming to implement for mass production.

By way of example, some digital reconstruction systems used can be used in cases of severe bone loss, such as to the glenoid. With digital reconstruction systems, a patient-matched implant is created to fill bone voids. This requires work to be done by engineers and other personnel at a dedicated manufacturing facility in advance of surgery, and requires a custom implant to be sent to the surgical facility prior to surgery.

OVERVIEW

Examples of the present application are described in reference to the shoulder joint of a patient. However, it should be recognized that the techniques, methods, systems and prostheses described can be applicable to any anatomical feature including any joint of the patient. The anatomical feature can also include a non-joint portion of a bone or other anatomy of the patient (e.g., soft tissue) in some cases.

According to some examples of the present application, a combination of a first prosthesis, a second prosthesis and an alignment guide are disclosed. The first prosthesis can be a material configured to substantially take a shape of and substantially fill a volume of a defect in a bone of the patient. The second prosthesis can have a stock construction (i.e. can come in various predetermined standard sizes and can have a predetermined shape that is common to all the prostheses produced—these and other characteristics are not changed on a patient by patient basis in view of imaging data obtained using a medical imaging technique on a specific patient). According to one example, the second prosthesis can be implanted in the joint on at least a portion of the first prosthesis once the first prosthesis is formed to substantially take the shape of and substantially fill the volume of the defect. The alignment guide can be configured to couple to the second prosthesis to retain the second prosthesis in a desired position and a desired orientation in the joint on the at least the portion of the first prosthesis (e.g., while the first prosthesis cures).

According to the disclosed examples, one or both of the alignment guide and the first prosthesis can treat the defect in the bone and can allow a stock implant (the second prosthesis) to be provided with the desired position and the desired orientation. In this manner, the present disclosed devices, systems and methods can avoid the use of PSI for the second prosthesis, as the second prosthesis can be implanted in the desired position and the desired orientation despite being stock. As such, the additional costs and additional time that would otherwise be incurred had a PSI prosthesis been utilized (rather than the stock prosthesis) can be avoided.

To further illustrate the apparatuses, systems and methods disclosed herein, a non-limiting list of examples is provided here:

Example 1 is a system for treating a defect in a bone that forms at least a portion of a joint of a patient, the system can optionally include: a first prosthesis comprising a formable material; a second prosthesis having a stock construction, the second prosthesis configured to be implanted in the joint on at least a portion of the first prosthesis once the first prosthesis is formed to take a shape of and substantially fill a volume of the defect; and an alignment guide configured to couple to the second prosthesis to retain the second prosthesis in a desired position and a desired orientation in the joint on the at least the portion of the first prosthesis.

In Example 2, the subject matter of Example 1 can optionally include the first prosthesis comprises one or more of a bone graft, bone, and a synthetic bone putty.

In Example 3, the subject matter of any one or more of Examples 1-2 can optionally include the first prosthesis in combination with the alignment guide provide for the desired position and the desired orientation of the second prosthesis relative to the joint.

In Example 4, the subject matter of any one or more of Examples 1-3 can optionally include a first mold configured to form the first prosthesis, wherein the first mold is formed based on imaging data obtained using a medical imaging technique performed on the joint of the patient, and wherein the first mold includes a cavity that replicates the volume of the defect.

In Example 5, the subject matter of Example 4 can optionally include the first mold includes one or more of a surface and a second cavity configured to replicate an articular surface of the joint.

In Example 6, the subject matter of any one or more of Examples 1-5 can optionally include a resection guide configured to position a cutting tool at the joint to perform a resection to remove at least a portion of joint including the defect to create a void with a desired shape in the joint.

In Example 7, the subject matter of Example 6 can optionally include the first prosthesis is configured to substantially take a shape of the void either by insertion into the joint and the void or by being formed in a second mold having a cavity that replicates a volume of the void.

In Example 8, the subject matter of any one or more of Examples 1-7 can optionally include wherein the alignment guide has one of a stock construction or a patient specific construction.

In Example 9, the subject matter of Example 8 can optionally include wherein the patient specific construction includes a guide surface configured to nest and closely conform to a first surface such that the guide surface mates with the first surface when the alignment guide is in only one orientation.

In Example 10, the subject matter of Example 9 can optionally include wherein the first surface comprises at least one of a surface or an edge of the first mold or the second mold, a surface of the bone that forms the joint, a second surface of the bone that forms the joint the second surface external of the joint, and a surface of a second bone.

In Example 11, the subject matter of Example 10 can optionally include wherein the joint comprises a shoulder and the bone comprises a scapula, and wherein the defect is in a glenoid of the scapula but the first surface comprises a second portion of the scapula external of the glenoid.

Example 12 is an assembly for treating a defect in a bone that forms at least a portion of a joint of a patient, the assembly can optionally include: a first prosthesis comprising a formable material that is formed to take a shape of and substantially fill a volume of the defect; a second prosthesis having a stock construction, the second prosthesis implanted in the joint on at least a portion of the first prosthesis; and an alignment guide connected to the second prosthesis to retain the second prosthesis in a desired position and a desired orientation in the joint on the at least the portion of the first prosthesis.

In Example 13, the subject matter of Example 12 can optionally include wherein the first prosthesis comprises one or more of a bone graft, bone, and a synthetic bone putty.

In Example 14, the subject matter of any one or more of Examples 12-13 can optionally include wherein the first prosthesis in combination with the alignment guide provide for the desired position and the desired orientation of the second prosthesis.

In Example 15, the subject matter of any one or more of Examples 12-14 can optionally include wherein the first prosthesis substantially takes the shape of the defect either by insertion into the defect or by being formed in a mold prior to insertion into the joint.

In Example 16, the subject matter of Example 15 can optionally include wherein the mold is inserted into the joint and the alignment guide is connected to the mold.

In Example 17, the subject matter of any one or more of Examples 12-16 can optionally include wherein the alignment guide has one of a stock shape or a patient specific shape.

In Example 18, the subject matter of Example 17 can optionally include the patient specific shape includes a guide surface configured to nest and closely conform to a first surface such that the guide surface mates with the first surface when the alignment guide is in only one orientation.

In Example 19, the subject matter of Example 18 can optionally include the first surface comprises at least one of a surface or an edge of the mold, a surface of the bone that forms the joint, a second surface of the bone that forms the joint the second surface external of the joint, or a surface of a second bone.

Example 20 is a method of repairing a defect in a bone that forms at least a portion of a joint of a patient, the method can optionally include: receiving imaging data obtained using a medical imaging technique, the imaging data representing the joint of the patient; creating a three-dimensional model of the joint including the defect based on the imaging data; implanting a first prosthesis in the joint, the first prosthesis formable to take a shape of and substantially fill a volume of the defect; implanting a second prosthesis in the joint, the second prosthesis disposed on at least a portion of the first prosthesis; and coupling an alignment guide to the second prosthesis to retain the second prosthesis in a desired position and a desired orientation in the joint on the at least the portion of the first prosthesis.

In Example 21, the subject matter of Example 20 can optionally include forming a mold based upon the imaging data, the mold including a cavity that replicates the volume of the defect; and shaping the first prosthesis within the cavity.

In Example 22, the subject matter of any one or more of Examples 19-21 can optionally include providing a patient specific guide surface for the alignment guide based upon the imaging data, the guide surface configured to nest and closely conform to a first surface such that the guide surface mates with the first surface when the alignment guide is in only one orientation.

In Example 23, the subject matter of Example 22 can optionally include the first surface comprises at least one of a surface or an edge of the mold, a surface of the bone that forms the joint, a second surface of the bone that forms the joint the second surface external of the joint, or a surface of a second bone.

In Example 24, the subject matter of any one or more of Examples 20-23 can optionally include creating a three-dimensional model comprising a virtual resection guide based on the imaging data; fabricating a resection guide configured to guide a cutting tool in resecting the portion of the joint that includes the defect to create a void with a desired shape; and shaping the first prosthesis to substantially take a shape of the void either by insertion into the joint and the void or by being formed in a second mold having a cavity that replicates a volume of the void.

In Example 25, the apparatuses, system and/or method of any one or any combination of Examples 1-24 can optionally be configured such that all elements or options recited are available to use or select from.

These and other examples and features of the present apparatuses, systems and methods will be set forth in part in the following Detailed Description. This Overview is intended to provide non-limiting examples of the present subject matter—it is not intended to provide an exclusive or exhaustive explanation. The Detailed Description below is included to provide further information about the present systems and methods.

DETAILED DESCRIPTION

Example apparatuses, systems and methods are described including those for treating a defect in a bone that forms at least a portion of a joint of a patient are disclosed. The disclosed instruments and prostheses are for use in shoulder joint replacement, shoulder resurfacing procedures and other procedures related to the shoulder joint or the various bones of the shoulder joint, including the scapula (specifically the glenoid) and adjacent shoulder bones. The present techniques can be applied to anatomic shoulder replacement and reverse shoulder replacement.

As previously discussed, according to some examples a combination of a first prosthesis, a second prosthesis and an alignment guide are disclosed. The alignment guide and/or the first prosthesis can be used with the second prosthesis, which can have a stock construction. According to the disclosed examples, one or both of the alignment guide and the first prosthesis can treat the defect in the bone and can allow the second prosthesis (of stock construction) to be provided with the desired position and the desired orientation. As such, the present disclosure can achieve additional cost and time savings as the second prosthesis need not be PSI. For example, the first prosthesis can accurately conform to the defect and substantially fill the defect to provide a continuous surface with the bone surface surrounding the defect. Additionally, the alignment guide can at least initially provide the desired position and the desired orientation for the second prosthesis. Thus, the natural movement of the shoulder joint, including glenoid version, may be reproduced.

According to some examples of the present disclosure and for various instruments and prostheses, PSI can be utilized. PSI can include, for example, molds, molding guides, cutting/resection guides or alignment guides. However, according to other examples various of the instruments and prostheses disclosed may not be PSI in nature but rather of stock or other construction. Indeed, the prostheses described in many of the examples provided comprise stock (conventional) prostheses. However, in other cases one or more of the prostheses can be PSI that can be prepared using computer-assisted image methods.

The term “PSI”, “custom-made” or “customized” are defined herein to apply to components, including tools (e.g., guides), molds, prostheses, portions or combinations thereof, which include geometric features, including surfaces, curves, or other lines that are made to closely conform as mirror-images or negatives to corresponding anatomical landmarks (features, surfaces, voids, etc.) of an individual patient's anatomy. In some examples, the geometric features, including surfaces, curves, or other lines can only mate with the corresponding anatomical landmark when the tool, mold, prosthesis, etc. is oriented in a single position. In the case of a PSI surface, such surface can be complementary to a corresponding surface of a patient's anatomy.

Imaging data used for PSI can be obtained or gathered during a pre-operative planning stage based on three-dimensional computer images of the corresponding anatomy reconstructed from image scans of the patient by computer imaging methods. Such images scans can be gathered using any known imaging modality including x-ray, ultrasound, magnetic resonance imaging (MRI) or a computed tomography (CT scan) of the individual patient's anatomy, for example. Further, PSI features can include guiding surfaces, guiding apertures, guiding slots, or other holes or openings. Such PSI features can be included in prostheses, alignment guides, resection guides, rasps or other instruments. These PSI features can be constructed (via use of three-dimensional modeling) to have positions, orientations, dimensions, shapes and/or define cutting planes and axes specific to the particular patient's anatomy including various anatomic or mechanical axes based on the computer-assisted pre-operative plan associated with the individual patient.

PSI should be contrasted with “stock”, “conventional”, “non-custom” or “off-the-shelf”, which are defined herein to apply to components (e.g., tools (such as guides), molds, prostheses) that come in various predetermined standard sizes and, in some cases, have a predetermined shape that is common to all the prostheses produced. These and other characteristics are not changed on a patient by patient basis in view of imaging data obtained using a medical imaging technique on a specific patient.

Referring to the drawings, and more particularly toFIG. 1, a medical imaging technique for obtaining imaging data representing a shoulder joint10is illustrated. The shoulder joint10includes a clavicle12, a scapula14having a glenoid16, and a humerus18having a head20that articulates within the glenoid16. Medical imaging techniques that can be employed to obtain imaging data include, but are not limited to CT scan, MRI, x-ray, and ultrasound. An imaging device21, such as a scanner, scans the shoulder joint10to generate imaging data representing the shoulder joint10. The imaging data may represent two-dimensional or three-dimensional images of the shoulder joint10. In one example, the imaging data represents two-dimensional sliced images of the shoulder joint10depicting cross-sections of the shoulder joint10that can be approximately a same distance apart from each other.

InFIGS. 2A and 2B, a three-dimensional model22of the scapula14, including the glenoid fossa16, is illustrated. The three-dimensional model22can be generated based on the imaging data obtained using a medical imaging technique such as illustrated inFIG. 1. The three-dimensional model22can be generated using software that generates three-dimensional models of an anatomical feature based on two-dimensional or three-dimensional imaging data corresponding to the anatomical feature. In one example, the three-dimensional model22can be generated using a process referred to as segmentation in which two-dimensional sliced images are converted into the three-dimensional model.

The scapula14can include an articular surface24, which the humeral head20(FIG. 1) articulates relative to. Additionally, the scapula14can have a non-articular or perimeter surface26that surrounds the articular surface24. The articular surface24forms the concave glenoid16(also referred to as the glenoid fossa) that receives the humeral head20(FIG. 1). In the example ofFIGS. 2A and 2B, the glenoid16includes a defect28, such as a void in the articular surface24. This defect28can be the result of severe wear. The defect28can make it difficult to mount a conventional prosthesis, or indeed PSI prosthesis, on the glenoid16to achieve a proper position and orientation for the prosthesis for proper joint kinematics.

The articular surface24can include an outer surface30. Such outer surface30can surround the defect28completely in some examples. The articular surface24can also include an irregular surface32at the location of the defect28. The irregular surface32can define at least a portion of the volume of the defect28. The irregular surface32can be recessed relative to the outer surface30, as shown, which results in the void (depression) in the glenoid16.

FIG. 3shows placement of a first prosthesis150onto the defect28in the glenoid16. Additionally,FIG. 3shows placement of a second prosthesis200on the glenoid16, such placement can be at least partially on the first prosthesis150, which can be implanted prior to the second prosthesis200. The second prosthesis200can include a body202and fasteners204.

The first prosthesis150can comprise of a formable material so as to substantially take the shape of and substantially fill a volume of the defect28. Thus, the first prosthesis150can be malleable and/or compressible according to some examples. More particularly, the first prosthesis150represents the final product after the formable material is shaped to match the surface of the defect28(e.g., the irregular surface32ofFIGS. 2A and 2B) and to form a continuous surface with the surface surrounding the defect (e.g., the outer surface30ofFIGS. 2A and 2B). The first prosthesis150can be formed using a mold such as the mold subsequently described in reference to ofFIGS. 4A and 4B. Alternatively, the first prosthesis150can be shaped in vivo by being inserted into the defect28and can be formed by hand or tool.

According to some examples, the first prosthesis150can include at least two distinct surfaces—a first surface152, which can nest with the irregular surface32and substantially fill the volume of the defect28, and a second surface154, which matches the surrounding articular surface. The first prosthesis150can be formed from many different formable materials such as, bone graft, autologous bone, allograft bone, xenograft bone, cortical bone, cancellous bone, and/or synthetic bone. In some cases, one or more of these can be provided in the form of a putty. Synthetic bone can include porous ceramic, such as Cerament™, having a density similar to that of cortical or cancellous bone. Alternatively, the first prosthesis150can be formed from a porous metal and a surgeon may insert growth factor and/or cancellous bone into the first prosthesis150. As such, before placing the first prosthesis150onto the defect28, a surgeon can apply growth factor to the first prosthesis150to facilitate formation of a bond between the first prosthesis150and the glenoid16.

If a mold is utilized to pre-form the first prosthesis150prior to placing the first prosthesis150in the defect28, the surgeon can align an outer perimeter156of the first prosthesis150with an outer perimeter158of the defect28. The first surface152of the first prosthesis150can be designed to match the irregular surface32of the defect28such that there can be only one orientation for the first prosthesis150to mate with the defect28. Once the first prosthesis150is in position, the second surface154can cooperate with the outer surface30surrounding the defect28to form a continuous articular surface. According to some examples, the surgeon can secure the first prosthesis150to the glenoid fossa16using fasteners or Kirschner wires (K-wires).

After implantation of the first prosthesis150, the second prosthesis200can be installed. Thus, the second prosthesis200can be configured to be implanted in the joint once the first prosthesis150is formed to take the shape of and substantially fill the volume of the defect28. In some examples, the second prosthesis200can be implanted on at least a portion of the first prosthesis150in addition to the glenoid16. The second prosthesis200can include the body202, which extends outward from the bone. The fasteners204or another type of fixation feature (e.g., pins, bone cement, K-wires, etc.) can retain the second prosthesis200in the joint. In some examples, the second prosthesis200can be retained in the joint by the first prosthesis150once the first prosthesis150has cured. The body202can be configured to connect to another implant (not shown) or another portion of the second prosthesis200(not shown). The shape of this portion can depend upon whether the second prosthesis200is being used as part an anatomic shoulder replacement or a reverse shoulder replacement, for example.

According to the example ofFIG. 3, the second prosthesis200can have a stock construction. As will be discussed and illustrated subsequently in reference toFIG. 5, the second prosthesis200can be retained on the glenoid16and on at least a portion of the first implant150in a desired position and a desired orientation by an alignment guide.

FIGS. 4A and 4Bshow a mold50for creating the first prosthesis150(shown formed inFIG. 4B) for repairing the defect28in the glenoid16(shown inFIGS. 1, 2A and 2B).FIG. 4Ashows the first prosthesis150prior to being formed in the mold50.FIG. 4Bshows the first prosthesis150after being formed in the mold50.

The mold50can be created based on a three-dimensional model such as the three-dimensional model22ofFIG. 2A. The mold50can be formed from a material such as a plastic, metal, other material or combination thereof, for example. In some examples, a manufacturing process such as machining, molding, and/or additive manufacturing can be used to create the mold50.

As shown inFIG. 4A, the mold50can include a cavity52that replicates the volume of the defect28. The cavity52also can include a first surface54that matches an actual surface of the defect28such as the irregular surface32ofFIGS. 2A and 2B. The cavity52can include a second surface56that can be configured to match an outer surface of the anatomical feature surrounding the defect such as the outer surface30(FIGS. 2A and 2B). Thus, the second surface56can be configured to match a portion of the articular surface24of the glenoid16that surrounds the defect28in the glenoid16.

The mold50can have an open design (i.e. have two parts), or can be a closed design with a riser that allows insertion of formable material102(shown inFIG. 4A), into the cavity52. By having the first and second surfaces54,56in the mold50, the first prosthesis150can be precisely made to fit the defect volume, as well as match the articular surface.

According to some examples, a three-dimensional model of the mold (not shown) can be provided to a surgeon as part of a preoperative plan. Thus, the three-dimensional model can be provided to the surgeon before the mold50is formed. The surgeon can review the three-dimensional model and can provide direction via electronic input regarding the mold50construction. Additionally or alternatively, the surgeon can alter the three-dimensional model to communicate design changes via the electronic input. The mold50can then be formed based on the original three-dimensional model and/or the further input the surgeon provides.

As shown inFIG. 4B, the surgeon can use the mold50to form the first prosthesis150for repairing the defect, for example, by filling the three-dimensional volume of the mold50. Once formed in the mold50, the surgeon can remove the first prosthesis150therefrom and transfer the first prosthesis150to the joint to fill the defect28as previously shown and discussed in reference toFIG. 3.

FIG. 5shows a system230that includes the combination of the first prosthesis150and the second prosthesis200as previously described in reference toFIG. 3with the first prosthesis150and the second prosthesis200installed in the joint. In particular,FIG. 5shows the patients' shoulder joint10including the glenoid16with the first prosthesis150and the second prosthesis200implanted thereon.FIG. 5also shows additional features of the scapula14. In the example ofFIG. 5, the first prosthesis150is implanted into the defect28(not shown) to substantially fill the defect28. As previously described inFIG. 3, the second prosthesis200can be implanted over the first prosthesis150. In some cases, the second prosthesis200can extend to be implanted into other portions of the glenoid16and/or scapula14.

As show inFIG. 5, the system230(shown as an assembly232) can include the first prosthesis150and the second prosthesis200and additionally an alignment guide250. According to the example ofFIG. 5, the alignment guide250can be configured to couple to the second prosthesis200to retain the second prosthesis200in a desired position and a desired orientation in the joint on the at least the portion of the first prosthesis150. Coupling of the alignment guide250with the second prosthesis200can be accomplished with a mechanical connection such as a pin252. According to some examples, the coupling of the alignment guide250with the second prosthesis200can be temporary, and the alignment guide250can be decoupled from the second prosthesis200and removed from the patient once the second prosthesis200is securely implanted (e.g., by curing of the first prosthesis150).

As previously discussed in reference toFIG. 3, according to some examples the second prosthesis200can have a stock construction. This can save costs and preoperative planning time v. if the second prosthesis were PSI. However, even with the second prosthesis200comprising a stock implant, the desired position and the desired orientation for the second prosthesis200can still be achieved with the aid of the alignment guide250. Additionally or alternatively, the first prosthesis150in combination with the alignment guide250can provide for the desired position and the desired orientation of the second prosthesis200in the joint. The desired position and the desired orientation can be determined preoperatively, for example, with the aid of three-dimensional model22ofFIGS. 2A and 2B. Furthermore, the desired position and the desired orientation for the second prosthesis200can be measured relative to any one or any combination of one or more articular surfaces of the joint, a center point of an anatomic feature (e.g., a center point of the glenoid), anatomic axes, anatomic features, a desired version (can be based upon a natural version), a desired inclination (can be based upon a natural inclination), or the like.

The alignment guide250can have one of a stock construction or a patient specific (i.e. PSI) construction. For example, the alignment guide250can include at least one guide surface254that is PSI in nature so as to be configured to nest and closely conform to a first surface (e.g., surface256of the scapula14) such that the at least one guide surface254mates with the first surface256when the alignment guide250is in only one orientation. Thus, the alignment guide250can reference a surface or portion of the scapula14in order to position and orient the alignment guide250to achieve the desired position and the desired orientation for the second prosthesis200.

More particularly, the alignment guide250can further include an arm260that extends away from a guide portion262, and a head264that can be fixed to an end of the arm260opposite the guide portion262. The head264can include the at least one guide surface254that can be PSI as discussed above. The guide portion262can be configured to connect to the second prosthesis200(e.g., via a pin252). In some examples, the guide portion262and the arm260and/or the guide portion262and the head264can be moveably attached. For instance, in some embodiments, the alignment guide200can include a movable coupling, such as a pivoting joint, that moveably couples the guide portion262and the arm260. Thus, in some examples the alignment guide200can move between a collapsed position and an extended position to engage with the surface256of the scapula15as shown.

The alignment guide200is illustrated as engaging the acromion of the scapula14external to the shoulder joint12inFIG. 5. However, in other examples the alignment guide200can contact any surface of the scapula14external of or within the shoulder joint12including one or more surfaces of features such as the scapular spine, a face and/or rim of the glenoid16, the coronoid process, scapular notch, scapular fossa, scapular border, etc.

FIG. 6shows a highly schematic view of a system300arranged as an assembly302on the glenoid16according to another example of the present application. The system300can include the first prosthesis150and the second prosthesis200as previously described. The first prosthesis150can be formed and implanted to fill the defect28in the glenoid16and the second prosthesis200can be implanted on at least a portion of the first prosthesis150as shown inFIG. 6. InFIG. 6, the first prosthesis150is illustrated as only partially filling the defect28in the glenoid16for demonstration purposes in order to also illustrate defect28. It is understood that in most examples the first prosthesis150would entirely fill the defect28. In some examples, the first prosthesis150could be allowed to cure prior to, during or after implantation of the second prosthesis200on the first prosthesis150.

The example ofFIG. 6also includes a mold304that can be used to create a level edge/surface to seat the first prosthesis150into the defect28. In some examples, the mold304can be removed prior to implantation of the second prosthesis200. However, in other examples the mold304or portions of the mold304can be retained on the glenoid16upon implantation of the second prosthesis200on the glenoid16(and on at least a portion of the first prosthesis150). The mold304can be constructed and designed in a manner previously discussed with regard to mold50ofFIGS. 4A and 4B.

The example ofFIG. 6also includes alignment guides306A,306B and306C configured to connect to at least a first surface (e.g., at least one of a surface or an edge of the mold, a surface of the bone that forms the joint, a second surface of the bone that forms the joint the second surface external of the joint, and a surface of a second bone). Two or more of the alignment guides306A,306B and306C can be used together in some cases. According to other examples the alignment guides306A,306B and306C can be used singularly as alternatives to one another. As shown inFIG. 6, the alignment guide306A can connect to the second prosthesis200and can additionally extend to connect to at least one of a surface308or an edge310of the mold304. The alignment guide306B can connect to the second prosthesis200and can additionally extend to connect to a surface of the glenoid16(i.e. a surface of the bone that forms the joint). The alignment guide306C can connect to the second prosthesis200and can additionally extend to connect to a second bone312(e.g., a clavicle, a rib, etc.).

The alignment guides306A,306B and306C can be used to orient the second prosthesis200, which can be a stock prosthesis, in a desired anatomical orientation. Additionally, the alignment guides306A,306B and306C can optionally be used to retain the second prosthesis200only while the first prosthesis150is curing. After curing of the first prosthesis150, the second prosthesis200can be coupled to the first prosthesis150in a desired anatomical orientation. In such instances, the alignment guides306A,306B and306C can then be removed. Furthermore, although the second prosthesis200is illustrated as larger than the first prosthesis150in the example provided inFIG. 6, it is contemplated that in many instances the second prosthesis200will be smaller than the first prosthesis150such that the second prosthesis200can fit within the bounds of the first prosthesis150. In other words, a stock implant (the second prosthesis200) can be entirely or at least partially surrounded by PSI surfaces created by the mold304.

FIG. 7shows a resection guide400fixed to the glenoid16near a defect401such as a void in the glenoid16. The defect401can occur due to severe wear. The resection guide400can be created based on a three-dimensional model of the glenoid16similar to the three-dimensional model22ofFIGS. 2A and 2B. The resection guide400can be formed from a material such as plastic, metal or another material or combination of materials. Fabrication of the resection guide400can be via machining, molding, and/or additive manufacturing, for example.

The resection guide400can include a handle402, a locating member404, and a guide member406. The locating member404can engage an irregular surface207A of the defect401to locate the resection guide400relative to the glenoid16. As such, the locating member404can include a nesting surface407B that is configured to mirror and nestingly engage the irregular surface407B or volume of the defect401. The nesting surface407B can be configured such that there is only one way for the resection guide400to mate and fit onto the scapula14. Once located, the resection guide400can be fixed to the glenoid16using fasteners408such as screws. A cutting tool can then be inserted into elongated cutting slots410,412in the guide member406. The slots210,212can be configured to guide the cutting tool along cut lines214,216, respectively. The cutting tool may be inserted into the glenoid16at a desired depth using, for example, depth markings.

Resection of the glenoid16facilitated by the resection guide400to remove the defect401can then occur leaving linear surfaces418A,418B and edges as wells as a void450as shown inFIG. 8. The resection guide400can then be removed.

A first prosthesis150A can then be formed either in vivo or with a mold as previously discussed. Thus, the first prosthesis150A can match the surface of the void450and can form a continuous surface with the articular surface surrounding the void450according to some examples. As the void450has a known shape with substantially smoother surfaces than would otherwise be the case with defect401present, the first prosthesis150A can be constructed to conform to and substantially fill the void450more easily. For example, the void450and the first prosthesis150A can have the shape of a wedge, with an angle θ between surfaces454,456of the first prosthesis150A and between respective surfaces418A and418B on the void450. In some cases, the first prosthesis150A can have an angle θ that is slightly different than that of the void450to exert a pressure on the surfaces418A and418B to facilitate integration of the first prosthesis150A. The second prosthesis200can then be implanted over at least a portion of the first prosthesis150A.

ADDITIONAL NOTES