Patent ID: 12208011

DETAILED DESCRIPTION

The embodiments described herein are directed to implants including portions for insertion within recesses in bone. The portions configured for insertion within the recesses each include a body having a substrate or central portion and a multi-layer bone interfacing lattice. The layers of the bone interfacing lattice may include elongate curved structural members. Such structural members may have any of a variety of curved configurations. For example, the structural members may include portions that are helical, spiraled, coiled, sinusoidal, arched, or otherwise curved. Examples of such curved configurations are provided in the following applications.

In addition to the various provisions discussed below, any of the embodiments disclosed herein may make use of any of the body/support structures, frames, plates, coils or other structures disclosed in McShane III et al., U.S. Pat. No. 10,478,312, issued on Nov. 19, 2019, and titled “Implant with Protected Fusion Zones,” and which is incorporated herein by reference in its entirety. For purposes of convenience, this application will be referred to throughout the present application as “The Protective Fusion Zones application.”

Also, any of the embodiments disclosed herein may make use of any of the body/support structures, elements, frames, plates or other structures disclosed in McShane III et al., U.S. Publication Number 2017/0042697, published on Feb. 16, 2017, and titled “Implant with Arched Bone Contacting Elements,” and which is incorporated herein by reference in its entirety.

Also, any of the embodiments disclosed herein may make use of any of the body/support structures, elements, frames, plates or other structures disclosed in Bishop et al., U.S. Pat. No. 10,512,549, issued on Dec. 24, 2019, and titled “Implant with Structural Members Arranged Around a Ring,” and which is incorporated herein by reference in its entirety and referred to herein as “The Ring application.”

Also, any of the embodiments disclosed herein may make use of any of the body/support structures, elements, frames, plates, or other structures disclosed in Morris et al., U.S. Publication Number 2016/0324656, published on Nov. 10, 2016, and titled “Coiled Implants and Systems and Methods of Use Thereof,” and which is incorporated herein by reference in its entirety and referred to herein as “The Coiled Implant Application.”

Also, any of the embodiments disclosed herein may make use of any of the body/support structures, elements, frames, plates, or other structures disclosed in Nyahay et al., U.S. Pat. No. 10,357,377, issued on Jul. 23, 2019, and entitled “Implant with Bone Contacting Elements Having Helical and Undulating Planar Geometries,” and which is incorporated herein by reference in its entirety.

Also, any of the embodiments disclosed herein may make use of any of the body/support structures, elements, frames, plates, or other structures disclosed in Nyahay et al., U.S. Pat. No. 10,667,924, issued on Jun. 2, 2020, and entitled “Corpectomy Implant,” and which is incorporated herein by reference in its entirety.

Also, any of the embodiments disclosed herein may make use of any of the body/support structures, elements, frames, plates, or other structures disclosed in Bishop et al., U.S. Pat. No. 10,213,317, issued Feb. 26, 2019, and entitled “Implant with Supported Helical Members,” and which is incorporated herein by reference in its entirety.

As used herein, the term “fixedly attached” shall refer to two components joined in a manner such that the components may not be readily separated (for example, without destroying one or both components).

For purposes of clarity, reference is made to various directional adjectives throughout the detailed description and in the claims. As used herein, the term “anterior” refers to a side or portion of an implant that is intended to be oriented towards the front of the human body when the implant has been placed in the body. Likewise, the term “posterior” refers to a side or portion of an implant that is intended to be oriented towards the back of the human body following implantation. In addition, the term “superior” refers to a side or portion of an implant that is intended to be oriented towards a top (e.g., the head) of the body while “inferior” refers to a side or portion of an implant that is intended to be oriented towards a bottom of the body. Reference is also made herein to “lateral” sides or portions of an implant, which are sides, or portions, facing along a lateral direction of the body (and which correspond with the left or right sides of a patient).

An implant may also be associated with various reference planes or surfaces. As used herein, the term “median plane” refers to a vertical plane which passes from the anterior side to the posterior side of the implant, dividing the implant into right and left halves, or lateral halves. As used herein, the term “transverse plane” refers to a horizontal plane that divides the implant into superior and inferior portions. As used herein, the term “coronal plane” refers to a vertical plane located in the center of the implant that divides the implant into anterior and posterior halves. In some embodiments, the implant is symmetric about one or more of these planes.

FIG.1is a schematic cutaway cross-sectional view of a bone having a recess and a longitudinal cross-sectional view of a portion of an implant configured to be inserted into the recess in the bone. As shown inFIG.1, a portion of an implant100may include a body105. Body105may include a substrate110and a bone interfacing lattice115disposed on substrate110.

Bone interfacing lattice115may be fixedly attached to substrate110in any suitable manner. For example, in some embodiments, body105may be 3D printed, such that substrate110and bone interfacing lattice115are a continuous unitary structure. In other embodiments, bone interfacing lattice115may be sintered, welded, thermally bonded, or otherwise joined to substrate115.

FIG.1also shows a portion of a bone200, illustrated in a cutaway cross-sectional view. As shown inFIG.1, bone200includes a recess205. In some cases, recess205may be substantially naturally occurring in the bone. For example, in some cases, recess205may be a medullary cavity. In order prepare a medullary cavity for insertion of an implant, bone marrow may be removed from the medullary cavity. In addition, portions of the cancellous bone lining the medullary cavity may also be removed, to provide an inner bone surface that is primarily cortical bone. In other cases, recess205may be wholly formed by surgical tools. For example, in some cases, a recess may be bored, reamed, or otherwise surgically formed in cortical bone or trabecular bone.

Portions of implants configured to be inserted into recesses in bone may include provisions to promote bone ingrowth. For example, bone interfacing surfaces of implants may include porous structures, such as a lattice of elongate curved structural members. In some embodiments, the porous structures may include provisions to maximize the amount of surface contact between the porous bone interfacing lattice of the implants and the bone. For example, in some embodiments, the bone interfacing lattice may include portions that are conformable to the interior wall of the recess in the bone.

As shown inFIG.1, in some embodiments, body105of implant100may have a substantially elongate shape configured to be inserted into recess205in bone200. For example, body105may be elongate along a central longitudinal axis135. Body105of implant100is illustrated as being a substantially conical shape. Other elongate shapes are also envisioned, including substantially cylindrical rods or posts. Further, any suitable cross-sectional shape may be used, including circular, oval, square, rectangular, triangular, and any other suitable shape.

The bone interfacing lattice may include at least two layers having differing deformabilities. For example, inner layers (positioned closer to the substrate) may have a low deformability (or even substantially no deformability in practical use). Outer layers (positioned further from the substrate) may have greater deformability. Accordingly, these outer layers may deform in order to conform to the inner wall of the recess in the bone. The bone interfacing lattice includes at least two layers of elongate curved structural members. In some embodiments, the bone interfacing lattice may have three or more layers of elongate curved structural members, wherein the three or more layers have differing deformabilities.

As shown inFIG.1, bone interfacing lattice115may include three layers. For example, a first layer120may be disposed adjacent substrate110. In addition, lattice115may include a second layer125disposed adjacent first layer120outward of first layer120relative to central longitudinal axis135. Also, lattice115may include a third layer130adjacent second layer125and outward of second layer125.

The layers of bone interfacing lattice115may be fixedly attached to one another in any suitable manner. For example, in some embodiments, body105may be 3D printed, such that the layers form a continuous unitary structure. In other embodiments, the layers may be sintered, welded, thermally bonded, or otherwise joined to one another. In addition, first layer120may be fixedly attached to substrate110.

First layer120may have a first deformability, second layer125may have a second deformability, and third layer130may have a third deformability. In some embodiments, the second deformability of second layer125may be greater than the first deformability of first layer120. In addition, the third deformability of third layer130may be greater than the second deformability of second layer125.

Each layer of the lattice structure may include a plurality of elongate curved structural members. The configuration of the elongate curved structural members may vary from layer to layer in order to provide the respective layers with differing amounts of deformability. The layers can be deformable in any of a variety of ways (e.g., elastic vs. plastic deformation) described in more detail below. In addition, the configuration of the elongate curved structural members can differ in a variety of ways to provide the variance in deformability.

In some embodiments, the respective layers may be provided with differing amounts of elastic deformability. In some embodiments, the respective layers may be provided with differing amounts of plastic deformability. In some embodiments, a given layer may be configured to maintain its thickness but deform by bending as a whole. In other cases, a layer may be configured to collapse, for example, by compressing. Thus, in some embodiments, the layers of the lattice may have different compressibilities. For example, in some embodiments, outer layers may be more compressible than inner layers. That is, the outer layers may have a greater capacity for the thickness of the layers to collapse. In some embodiments, the further the layer is from the substrate of the implant, the greater the compressibility, with the outermost (i.e., bone contacting) layer being the most compressible.

In some embodiments, a combination of varying compressibility and varying deformability may be utilized. For example, in some embodiments, an innermost layer may be substantially non-deformable, an outermost layer may be deformable by bending, but may maintain its thickness despite deforming. That is, the outermost layer may deflect inward in order to conform to the inner surface of the bone recess. In order to permit the inward deflection of the outermost layer, an intermediate layer between the innermost layer and the outermost layer may be relatively compressible. Thus, the compressible intermediate layer may collapse in various locations to accommodate the inward deflection of the outermost layer. However, since the outermost layer does not collapse to reduce its thickness, the porosity of the outermost layer may be preserved in deflected areas, which may maximize the capacity of the outermost bone contacting layer to permit bone ingrowth. Other arrangements of layers having differing deformabilities are also possible. Among other alternatives, more than three layers may be used to form the lattice. In some embodiments, different portions of the same lattice layer may have different deformabilities.

In some embodiments, the densities of the elongate curved structural members may vary. For example, outer layers may have lower densities than inner layers. For purposes of this disclosure, the term densities shall refer to ratio of open space to volume occupied by elongate curved structural members. A lower density of structural members provides a layer with greater porosity. Thus, lower densities in the outer layers provide a more porous bone contacting surface. The greater porosity may facilitate bone ingrowth. In addition, the greater porosity may enable the outer layers to maintain a desired level of porosity even when the layers are partially compressed upon implantation.

In some embodiments, the outer layers may be formed of different materials than the inner layers. For example, in some embodiments, the outer layers may be formed of more flexible or more deformable materials than the inner layers.

In some embodiments, the gauge of the elongate curved structural members may differ from layer to layer. That is, the cross-sectional size of the elongate curved structural members may be larger in some layers and smaller in other layers. For example, in some embodiments, the further from the substrate a layer is disposed, the smaller the gauge of the elongate curved structural members in the layer. The smaller gauge renders the structural members to be more deformable (plastically or elastically).

As shown inFIG.1, each of first layer120, second layer125, and third layer130are formed of elongate curved structural members. Such structural members may have any of a variety of curved configurations. For example, the structural members may include portions that are helical, spiraled, coiled, sinusoidal, arched, or otherwise curved.

The configuration of curved structural members may be regular or irregular. That is, the members may be arranged in a regular pattern or in a random arrangement. Some of the structural members within each layer may overlap or intersect with one another. In some cases, the cross-sectional size and/or shape of a structural member could vary along its length (e.g., the diameter could change along the length of a structural member).

Embodiments can include provisions for protecting bone growth along and adjacent to elongate curved structural members of an implant. In some embodiments, an elongate curved structural member can be configured with a geometry that helps to protect new bone growth in selected regions or “protected fusion zones.” In some embodiments, an elongate curved structural member can have a spiral, helical or twisted geometry that provides a series of such protected fusion zones for enhanced bone growth.

Some elongate curved structural members may have a generalized helical geometry. As used herein, a “generalized helical geometry” or “spiraling geometry” refers to a geometry where a part (portion, member, etc.) winds, turns, twists, rotates or is otherwise curved around a fixed path. In some cases, the fixed path could be straight. In other cases, the fixed path can be curved. In the present embodiments, for example, the fixed path is generally a combination of straight segments and curved segments.

Curves having a generalized helical geometry (also referred to as generalized helical curves) may be characterized by “coils,” “turns,” or “windings” about a fixed path. Exemplary parameters that may characterize the specific geometry of a generalized helical curve can include coil diameter (including both a major and minor diameter) and the pitch (i.e., spacing between adjacent coils). In some cases, the “amplitude” of a coil or loop may also be used to describe the diameter or widthwise dimension of the coil or loop. Each of these parameters could be constant or could vary over the length of a generalized helical curve.

Generalized helical curves need not be circular or even round. In some embodiments, for example, a generalized helical curve could have linearly-segmented shape (or locally polygonal shape) such that each “coil” or “turn” is comprised of straight line segments rather than arcs or other curved segments. Generalized helical curves may also include combinations of curved and straight segments.

The arrangement of elongate curved structural members may be designed to achieve a desired total open volume. As used herein a total open volume is the combined volume of any openings between structural members or between structural members and the substrate. This open configuration may facilitate bone growth in and through the implant. A portion, or substantially all of, the open spaces may be filled with a bone graft or bone growth promoting material prior to insertion of the implant to facilitate bone growth.

The implantation process may begin with the application of a bone growth promoting material, also referred to as a BGPM, to the implant. As used herein, a “bone growth promoting material” is any material that helps bone growth. Bone growth promoting materials may include provisions that are freeze dried onto a surface or adhered to the metal through the use of linker molecules or a binder. Examples of bone growth promoting materials are any materials including bone morphogenetic proteins (BMPs), such as BMP-1, BMP-2, BMP-4, BMP-6, and BMP-7. These are hormones that convert stem cells into bone forming cells. Further examples include recombinant human BMPs (rhBMPs), such as rhBMP-2, rhBMP-4, and rhBMP-7. Still further examples include platelet derived growth factor (PDGF), fibroblast growth factor (FGF), collagen, BMP mimetic peptides, as well as RGD peptides. Generally, combinations of these chemicals may also be used. These chemicals can be applied using a sponge, matrix or gel.

Some bone growth promoting materials may also be applied to an implantable prosthesis through the use of a plasma spray or electrochemical techniques. Examples of these materials include, but are not limited to, hydroxyapatite, beta tri-calcium phosphate, calcium sulfate, calcium carbonate, as well as other chemicals.

A bone growth promoting material can include, or may be used in combination with a bone graft or a bone graft substitute. A variety of materials may serve as bone grafts or bone graft substitutes, including autografts (harvested from the iliac crest of the patient's body), allografts, demineralized bone matrix, and various synthetic materials.

Some embodiments may use autograft. Autograft provides the implantation site with calcium collagen scaffolding for the new bone to grow on (osteoconduction). Additionally, autograft contains bone-growing cells, mesenchymal stem cells and osteoblast that regenerate bone. Lastly, autograft contains bone-growing proteins, including bone morphogenic proteins (BMPs), to foster new bone growth in the patient.

Bone graft substitutes may comprise synthetic materials including calcium phosphates or hydroxyapatites, stem cell containing products which combine stem cells with one of the other classes of bone graft substitutes, and growth factor containing matrices such as INFUSE® (rhBMP-2-containing bone graft) from Medtronic, Inc.

It should be understood that the provisions listed here are not meant to be an exhaustive list of possible bone growth promoting materials, bone grafts, or bone graft substitutes.

In some embodiments, BGPM may be applied to one or more outer surfaces of an implant. In other embodiments, BGPM may be applied to internal volumes within an implant. In still other embodiments, BGPM may be applied to both external surfaces and internally within an implant.

As shown inFIG.1, the elongate curved structural members of first layer120may have a first gauge, the elongate curved structural members of second layer125may have a second gauge, and the elongate curved structural members of third layer130may have a third gauge. As further shown inFIG.1, the second gauge may be smaller than the first gauge, and the third gauge may be smaller than the second gauge. This difference in gauges may provide each of the layers with a different deformability.

Accordingly, the dimensions of the elongate curved structural members can vary. In some embodiments, the elongate curved structural members can have cross-sectional diameters ranging between 0.2 and 3 mm. For example, in some embodiments the elongate curved structural members of first layer120may be approximately 1.0 mm in diameter, the elongate curved structural members of second layer125may be approximately 0.6 mm in diameter, and the elongate curved structural members of third layer130may be approximately 0.3 mm in diameter.

FIG.2is a schematic transverse cross-sectional view of the implant shown inFIG.1. As shown inFIG.2, first layer120may have a first thickness that is substantially consistent such that an outer shape of first layer120is substantially the same as the outer shape of substrate110. In addition, second layer125may have a second thickness that is substantially consistent such that the outer shape of second layer125is substantially the same as the outer shape of first layer120. Further, third layer130may have a third thickness that is substantially consistent such that the outer shape of third layer130is substantially the same as the outer shape of second layer125. In other words, in some embodiments, the interfaces between layers may be concentric.

In some embodiments, the interface between layers may have a substantially negligible thickness. In other embodiments, the interface between the first layer and the second layer is a transition region having a thickness within which the elongate curved structural members of the first layer are intermingled with the elongate curved structural members of the second layer. Similarly, the interface between the second layer and the third layer may also be a transition region having a thickness, within which the elongate curved structural members of the second layer are intermingled with the elongate curved structural members of the third layer.

Implant100may be configured to be implanted within any of a variety of bones within the body of a human or animal. In some embodiments, body105of implant100may be configured for implantation into the medullary cavity of long bones, such as the femur or humerus. In some embodiments, body105of implant100may be configured for implantation into a drilled or reamed recess in cortical or trabecular bone.

FIG.3is a schematic cross-sectional view of bone200ofFIG.1with body105of implant100inserted into recess205. In addition,FIG.4is a schematic transverse cross-sectional view of bone200and implant100inserted as shown inFIG.3. As shown inFIGS.3and4, portions of third layer130and portions of second layer125may be deformed to conform with irregularities in the inner surface of recess205. In an area where bone200protrudes into recess205, such as protrusion210inFIG.4, one or more layers of implant100may deform as shown by a deformed area140inFIG.4.

FIG.5is a schematic enlarged cross-sectional view of bone200and implant100.FIG.5generally illustrates the different gauges of the elongate structural members in first layer120, second layer125, and third layer130. It will be noted that depiction of the size, shape, and general configuration of these layers is intended to be schematic. The elongate curved structural members can have any suitable shape and arrangement. The present disclosure is directed to the properties of the multi-layer lattice in terms of the relative deformabilities of the layers.

As shown inFIG.5, one or more layers of the lattice of implant100are deformable. Protrusion210of bone200represents an irregularity in a bone recess. While surgical tools are generally able to prepare a bone recess with minimal irregularities, the relative size of protrusion210is exaggerated inFIG.5for purposes of illustration. As shown inFIG.5, two of the layers of the lattice are deformed by protrusion210, resulting in a reduction in the thickness of the two deformed layers at the location of protrusion210. In particular, first layer120has a first undeformed thickness of145, second layer125has a second undeformed thickness150, and third layer130has a third undeformed thickness155. In the deformed area, third layer130has a deformed thickness160that is smaller than third undeformed thickness155. In addition, second layer125has a deformed thickness165that is smaller than second undeformed thickness150. In some embodiments, the deformability of the layers may differ. For example, in some embodiments, third layer130may deform more than second layer125.

FIG.6is a schematic enlarged view of three layers of elongate curved structural members. In some embodiments, the layers may be formed as a single unitary structure, for example, by 3D printing. As shown inFIG.6, in some embodiments, the transition between one layer to the next layer may occur in two dimensions. That is, the transition may have no thickness, such that adjacent layers are completely discreet. For example, as shown inFIG.6, a first transition170between first layer120and second layer125may have no thickness. Similarly, a second transition170between second layer125and third layer130may also have no thickness. This configuration may ensure that the deformabilities of the respective layers remain unchanged by the transitions between layers.

FIG.7is a schematic enlarged view of three layers of elongate curved structural members wherein the layers intermingle with one another at the respective boundaries.FIG.8is a schematic further enlarged view of the three layers of elongate curved structural members shown inFIG.7. As shown inFIG.8, in some embodiments, the transitions between layers may have a thickness. That is, there is a portion of the lattice where elongate curved structural members from one layer intermingle with the elongate curved structural members of the adjacent layer.FIG.8illustrates first layer120as having a first thickness180, second layer125as having a second thickness185, and third layer130as having a third thickness190. As further shown inFIG.8, first layer120and second layer125may intermingle to form a transition region195, which has a thickness, and therefore a volume. Similarly, second layer125may intermingle with third layer130to form a second transition region198, which has a thickness, and therefore a volume. This configuration may provide the lattice with additional strength, and prevent delamination of layers.

In some embodiments, some layer transitions may have a thickness, and others may not. For example, in some embodiments, the transition between the first (innermost) layer and the second layer may have a thickness, whereas the transition between the second (middle) layer and the third (outermost) layer may not have a thickness. In such embodiments, since the first layer may not deform much, if at all, having a transition with thickness to the second layer may not unduly alter the deformability of the first layer. Whereas, for the transition between the second layer and the third layer, a transition without thickness may be preferred in order to maintain the relative deformability properties of the respective layers and the lattice as a whole.

FIGS.3-5are schematic illustrations intended to generally illustrate a portion of an implant having a multi-layer bone interfacing lattice inserted into a portion of a bone.FIGS.3-5are not intended to be specific to a particular type of implant or a particular type of bone.FIGS.9-16illustrate exemplary embodiments in which such a multi-layer bone interfacing lattice may be implemented.

FIG.9is a schematic exploded view of a knee replacement implant system according to an exemplary embodiment. There are multiple components of a knee replacement system that can implement a multi-layer bone interfacing lattice. As shown inFIG.9, a knee replacement implant system900may include a femoral component905and a tibial component910. Femoral component905may be configured for mounting onto the distal end of a femur915. Femoral component905may include one or more posts920configured to be inserted into holes925in femur915which are drilled by the surgeon. Posts920may include a multi-layer bone interfacing lattice to facilitate maximum bone contacting surface within holes925. Stippling indicates general areas of posts920that may include a multi-layer bone interfacing lattice. Tibial component910may also include a post930configured for insertion into a recess935in the proximal end of a tibia940. Recess935may include a portion of the medullary cavity within the tibia, and may also be at least partially formed by the surgeon via cutting, drilling, reaming, or other bone shaping processes. Post930may also include a multi-layer bone interfacing lattice to facilitate maximum bone contacting surface within recess935. Stippling indicates general areas of post930that may include a multi-layer bone interfacing lattice.

In some embodiments, a multi-layer bone interfacing lattice may be implemented on metaphyseal sleeves. Such sleeves are utilized, for example, during revision surgeries when a significant amount of bone resorption has taken place. The sleeves take up the space between an implant post and the inner surface of the bone recess, which has become enlarged due to bone resorption and/or further reaming performed to prepare the recess for a new implant.

FIG.10is a schematic exploded view of a metaphyseal sleeve1000and a tibial plateau implant1005. As illustrated inFIG.10, metaphyseal sleeve1000may include a central hole1007configured to receive a post1008of tibial plateau implant1005. In addition, sleeve1000may include a bone interfacing lattice configured for implantation in a proximal end of a tibia1015. The lattice may include a plurality of concentric layers formed of elongate curved structural members. As shown inFIG.10, the lattice may include a first layer1020, a second layer1025, and a third layer1030.

As further shown inFIG.10, first layer1020may include elongate curved structural members having a first gauge. Second layer1025may include elongate curved structural members having a second gauge. Third layer1030may include elongate curved structural members having a third gauge. As shown inFIG.10, the second gauge may be smaller than the first gauge, and the third gauge may be smaller than the second gauge.

As also shown inFIG.10, in some embodiments, implant1000may include an inner sleeve1050. Inner sleeve1050may provide a substrate layer upon which first layer1020of elongate curved structural members may be formed. In addition, the inner surface of inner sleeve1050may be configured to mate with the surface of post1008of tibial plateau implant1005. For example, the two surfaces may have textures or other features to prevent or otherwise minimize the likelihood that post1008comes out of central hole1007.

FIG.11is a schematic view of a hip replacement implant system according to an exemplary embodiment. As shown inFIG.11, a hip replacement implant system1100may include a femoral component1105and pelvic component1106. Femoral component1105may be configured for mounting onto the proximal end of a femur1110. Femoral component1105may include a post1115configured to be inserted into a recess in femur1110. The recess may include a portion of the medullary cavity within femur1110, and may also be at least partially formed by the surgeon via cutting, drilling, reaming, or other bone shaping processes. Post1115may include a multi-layer bone interfacing lattice to facilitate maximum bone contacting surface within the recess of femur1110. Stippling indicates general areas of post1115that may include a multi-layer bone interfacing lattice.

As shown inFIG.11, pelvic component1106may be an acetabular cup configured for implantation in an acetabulum1120of a patient's pelvis1125. Pelvic component1106may include a substantially spherical outer surface1107. Outer surface1107may be configured to interface with acetabulum1120. Pelvic component1106may be affixed to acetabulum1120with several mechanisms. For example, pelvic component1106may be affixed to acetabulum1120with one or more screws.

In addition, the screw fixation of pelvic component1106may be supplemented with bone ingrowth into outer surfaces of pelvic component1106. For example, as shown inFIG.11, in some embodiments, outer surface1107of pelvic component1106may include a multi-layer bone interfacing lattice similar to that described in other embodiments discussed herein. The multi-layer bone interfacing lattice of outer surface1107may promote bone ingrowth into outer surface1107. Stippling indicates general areas of outer surface1107that may include a multi-layer bone interfacing lattice.

Additionally, in some embodiments, pelvic component1106may include one or more posts, such as a first post1108and a second post1109. Upon implantation of pelvic component1106, first post1108may be inserted into a first hole1130, which may be drilled into acetabulum1120. Similarly, upon implantation of pelvic component1106, second post1109may be inserted into a second hole1130, which may be drilled into acetabulum1120. In some embodiments, first post1108and second post1109may have outer surfaces including a multi-layer bone interfacing lattice similar to that described in other embodiments discussed herein. The multi-layer bone interfacing lattice of first post1108and second post1109may promote bone ingrowth into the surfaces of these posts, and thus, provide additional fixation of pelvic component1106to pelvis1125. Stippling indicates general areas of first post1108and second post1109that may include a multi-layer bone interfacing lattice.

FIG.12Ais a schematic view of a shoulder replacement implant system according to an exemplary embodiment. As shown inFIG.12A, a shoulder replacement implant system1200may include a humoral component1205and a glenoid component1220. Humoral component1205may be configured for mounting onto the proximal end of a humerus1210. Humoral component1205may include a post1215configured to be inserted into a recess in humerus1210. The recess may include a portion of the medullary cavity within humerus1210, and may also be at least partially formed by the surgeon via cutting, drilling, reaming, or other bone shaping processes. Post1215may include a multi-layer bone interfacing lattice to facilitate maximum bone contacting surface within the recess of humerus1210. Stippling indicates general areas of post1215that may include a multi-layer bone interfacing lattice.

FIG.12Bis a schematic exploded view of the glenoid side of the shoulder replacement implant system shown inFIG.12A. Glenoid component1220may be configured to be implanted in glenoid cavity1225of a patient's shoulder1230. Glenoid component1220may include a base component1235and a liner1240. Liner1240may be a low friction material, such as plastic, which may facilitate motion against humeral component1205(seeFIG.12A). Liner1240may be attached to base component1235, for example using a snap-in configuration.

Base component1235may be affixed within glenoid cavity1225with several mechanisms. For example, base component1235may be affixed within glenoid cavity1225by bone ingrowth into outer surfaces of base component1235. For example, as shown inFIG.12B, in some embodiments, a bone contacting surface1242of base component1235may include a multi-layer bone interfacing lattice similar to that described in other embodiments discussed herein. The multi-layer bone interfacing lattice of bone-contacting surface1242may promote bone ingrowth into outer surface1242. Stippling indicates general areas of bone-contacting surface1242that may include a multi-layer bone interfacing lattice.

Additionally, in some embodiments, base component1235may include one or more posts, such as a first post1245and a second post1250. Upon implantation of base component1235, first post1245may be inserted into a first hole1255, which may be drilled into glenoid cavity1225. Similarly, upon implantation of base component1235, second post1250may be inserted into a second hole1260, which may be drilled into glenoid cavity1225. In some embodiments, first post1245and second post1250may have outer surfaces including a multi-layer bone interfacing lattice similar to that described in other embodiments discussed herein. The multi-layer bone interfacing lattice of first post1245and second post1250may promote bone ingrowth into the surfaces of these posts, and thus, provide additional fixation of base component1235to glenoid cavity1225. Stippling indicates general areas of first post1245and second post1250that may include a multi-layer bone interfacing lattice.

FIG.13is a schematic assembled view of an ankle replacement implant system according to an exemplary embodiment. There are multiple components of an ankle replacement system that can implement a multi-layer bone interfacing lattice. As shown inFIG.13, an ankle replacement implant system1300may include a tibial component1305and a talar component1310. Tibial component1305may be configured for mounting onto the distal end of a tibia1315. Tibial component1305may include a baseplate1318and one or more posts1320extending from baseplate1318and configured to be inserted into one or more recesses in tibia1315. The recesses in tibia1315may include a portion of the medullary cavity within the tibia, and may also be at least partially formed by the surgeon via cutting, drilling, reaming, or other bone shaping processes. Posts1320may include a multi-layer bone interfacing lattice to facilitate maximum bone contacting surface within the recesses. Stippling indicates general areas of posts1320that may include a multi-layer bone interfacing lattice.

Baseplate1318may include a bone contacting surface having one or more recesses1340. Recesses1340may be at least partially filled with a multi-layer bone interfacing lattice to promote bone ingrowth.

Talar component1310may also include one or more posts1330configured for insertion into one or more recesses in the proximal end of a talus1335. The one or more recesses may be at least partially formed by the surgeon via cutting, drilling, reaming, or other bone shaping processes. Posts1330may also include a multi-layer bone interfacing lattice to facilitate maximum bone contacting surface within the recess. Stippling indicates general areas of posts1330that may include a multi-layer bone interfacing lattice.

FIG.14is a schematic assembled view of an ankle fusion implant system according to an exemplary embodiment. As shown inFIG.14, an ankle fusion implant system1400may include an intramedullary rod1405. Intramedullary rod1405may be configured for mounting onto the distal end of a tibia1410. As shown inFIG.14, intramedullary rod1405may also be inserted through a talus1415and a calcaneus1420. Intramedullary rod1405may be inserted within a recess in tibia1410that may include a portion of the medullary cavity within tibia1410. In addition, intramedullary rod1405may be inserted into recesses in talus1415and calcaneus1420that may be at least partially formed by the surgeon via cutting, drilling, reaming, or other bone shaping processes. Intramedullary rod1405may include a multi-layer bone interfacing lattice to facilitate maximum bone contacting surface within the recesses within the tibia and ankle bones. Stippling indicates general areas of intramedullary rod1405that may include a multi-layer bone interfacing lattice.

FIG.15is a schematic perspective view of an alternative intramedullary rod embodiment for an ankle fusion implant system.FIG.15shows an intramedullary rod1500. Intramedullary rod1500may include a plurality of elongate curved structural members1505. As shown inFIG.15, structural members1505may intersect at junctions1510that are recessed from the outermost envelope of intramedullary rod1500. Accordingly, the support member junctions are generally not located at the bone-implant interface when rod1500is implanted.

FIG.16is a schematic view of a hammertoe correction implant according to an exemplary embodiment. As shown inFIG.16, a hammertoe correction implant1600may be implanted into adjacent phalanges to fuse an interphalangeal joint. The outer surface of implant1600may include a multi-layer bone interfacing lattice of elongate curved structural members to facilitate bone ingrowth. For example, as shown inFIG.16, implant1600may include a first layer1620, a second layer1625, and a third layer1630. In some embodiments, implant160may have a central hole1607. Bone graft material may be placed in central hole1607to facilitate fixation and bone ingrowth.

FIG.16depicts a substantially cylindrical embodiment having a three layer lattice. This configuration may be used for any of a number of different intramedullary rods. In some embodiments, such cylindrical implants may be used to join adjacent bones, such as phalanges in the foot (as shown inFIG.16) or the hand. In other cases, such implants may be used to repair long bones, such as the humerus, femur, tibia, and other such bones. For severe breaks, long bones may be repaired by placing a rod inside the substantially hollow bone. The three layer lattice discussed herein may facilitate fixation and bone ingrowth for such intramedullary rods.

In addition, other intramedullary implants are also possible. For example, in some embodiments, an implant having dual, concentric helical members may be utilized.

FIG.17is a schematic perspective view of another substantially cylindrical implant configured for intramedullary implantation. As shown inFIG.17, an implant1700may include a first outer spiral1705and first inner spiral1710. In addition, implant1700may include a second outer spiral1715and a second inner spiral1720. This dual, concentric spiral configuration may provide structural support, while maintaining a substantially hollow inner volume to receive bone graft material and/or bone ingrowth.

The inner and outer spirals may have separate starting points akin to a dual-start thread. In addition, the inner and outer spirals may be joined to one another at the ends. For example, as shown inFIG.17, first outer spiral1705and first inner spiral1710may be joined by a first connecting portion1725. As also shown inFIG.17, second outer spiral1715and second inner spiral1720may be joined by a second connecting portion1730.

FIGS.18-20illustrate other views of implant1700. As shown inFIG.19, longitudinal spacing1750may be provided between spirals. Ain addition, as shown inFIG.20, the outer and inner spirals may be concentric. In addition, first inner spiral1710and second inner spiral1720may define a cylindrical central opening1735. In addition, the inner spirals and outer spirals may define an annular space1740between the inner spirals and the outer spirals. Central opening1735, annular space1740, and longitudinal spacing1750may be configured to receive bone graft material and/or bone ingrowth.

FIG.21is a schematic perspective view of a substantially cylindrical intramedullary implant according to another exemplary embodiment.FIG.21shows an implant2100being formed of a plurality of criss-crossing support members2105forming a substantially cylindrical grid or cage having a longitudinal axis2108. As shown inFIG.21, implant2100may have a bend in it, such that longitudinal axis2108has a curved portion. This bend may facilitate implantation into separate pieces of bone that are intended to be maintained at an angle with respect to one another.

Implant2100may be configured to be placed within elongate bones, such as phalanges of the hand or foot. In some cases, implant2100may be configured to be implanted in the intramedullary space of larger bones, such as the femur or humerus. In some embodiments a first end2110of implant2100may be inserted into a first bone or first piece of bone, and a second end2115of implant2100may be inserted into a separate bone or piece of bone. By inserting opposing ends of implant2100into separate bones (e.g., phalanges) or pieces of bones (e.g., broken long bones), implant2100may stabilize these bones to facilitate fusion of separate bones or healing of separate broken bone pieces.

In order to prevent egress of implant2100after implantation, implant2100may include one or more spikes2120. Spikes2120may be configured to facilitate insertion of implant2100but prevent removal of implant2100as well as preventing rotation of implant2100about longitudinal axis2108. For example, implant may include a first spike2125located proximate first end2110of implant2100. First spike2125may include a first surface2130facing away from first end2110and extending substantially perpendicularly with respect to longitudinal axis2108. First spike2125may also include a second surface2135facing toward first end2110of implant2100and extending at a non-zero angle with respect to longitudinal axis2108. That is, as second surface2135extends away from the surface of support members2105, second surface2135slopes away from first end2110of implant2100. The slope of second surface2135may facilitate insertion of implant2100and the perpendicular configuration of first surface2130may prevent removal of implant2100from within a bone into which it has been implanted.

As shown inFIG.21, spikes2120at opposing ends of implant2100may have sloped surfaces facing in opposite directions. That is, the spikes closest to first end2110may have sloped surfaces facing toward first end2110, as with first spike2125. And the spikes closest to second end2115may have sloped surfaces facing toward second end2115. For example, implant may include a second spike2140proximate to second end2115of implant2100. Second spike2140may include a first surface2145facing away from second end2115and extending substantially perpendicularly from longitudinal axis2108. In addition, second spike2140may include a second surface2150facing toward second end2115and extending at a non-zero angle with respect to longitudinal axis2108.

FIG.22is a schematic lateral view of the implant shown inFIG.21. As shown inFIG.22, in some embodiments, spikes2120may be disposed on opposing sides of implant2100. For example, implant2100may include a third spike2155disposed opposite first spike2125. Similarly, implant2100may include a fourth spike2160disposed opposite second spike2140. Accordingly, in at least one plane, implant2100may be substantially symmetrical about longitudinal axis2108.

FIG.23is a schematic perspective view of a substantially cylindrical intramedullary implant according to another exemplary embodiment. As shown inFIG.23, an implant2300may be formed of a plurality of spiral members2305extending about a central longitudinal axis2310. To support spiral members2305, implant2300may include a framework. The framework may be formed from a first substantially circular end member2315and a second substantially circular end member2320. A plurality of longitudinal members2325may extend between first substantially circular end member2315and second substantially circular end member2320. Spiral members2305may be supported by longitudinal members2325. Implant2300may have any suitable longitudinal length and radial diameter with respect to longitudinal axis2310. For example, implant2300may have a suitable size for implantation within small bones like phalanges or large bones such as the humerus or femur.

As illustrated inFIG.23, spiral members2305may have a substantially sinusoidal configuration, deviating in and out radially with respect to longitudinal axis2310. In addition, spiral members2305may include a plurality of flattened surfaces2335that collectively form at least a portion of the outer surface of implant2300. The structural members of implant2300define a central hollow cavity in the interior of implant2300. The central hollow cavity may be configured to receive bone graft material.

FIG.24is another schematic perspective view of the implant shown inFIG.23.FIG.24better shows the central hollow cavity, as well as the sinusoidal configuration of spiral members2305, as seen from the inside of implant2300.

FIG.25is a schematic lateral view of the implant shown inFIG.23.FIG.25illustrates the angle or pitch of spiral members2305.FIG.25also shows that flattened surfaces2335of spiral members2305alternate as to which side of longitudinal members2325they are disposed. This may provide an even distribution of surface area for the outer (bone contacting) surface of implant2300.

The various components of an implant may be fabricated from biocompatible materials suitable for implantation in a human body, including but not limited to, metals (e.g. titanium or other metals), synthetic polymers, ceramics, and/or their combinations, depending on the particular application and/or preference of a medical practitioner.

Generally, the implant can be formed from any suitable biocompatible, non-degradable material with sufficient strength. Typical materials include, but are not limited to, titanium, biocompatible titanium alloys (e.g. γTitanium Aluminides, Ti6—Al4—V ELI (ASTM F 136 and F 3001), or Ti6—Al4—V (ASTM F 2989, F 1108 and ASTM F 1472)) and inert, biocompatible polymers, such as polyether ether ketone (PEEK) (e.g. PEEK-OPTIMA®, Invibio Inc and Zeniva Solvay Inc.). Optionally, the implant contains a radiopaque marker to facilitate visualization during imaging.

In different embodiments, processes for making an implant can vary. In some embodiments, the entire implant may be manufactured and assembled via readditional/CNC machining, injection-molding, casting, insert-molding, co-extrusion, pultrusion, transfer molding, overmolding, compression molding, 3-Dimensional (3-D) printing (including Direct Metal Laser Sintering and Electron Beam Melting), dip-coating, spray-coating, powder-coating, porous-coating, milling from a solid stock material and their combinations. Moreover, the embodiments can make use of any of the features, parts, assemblies, processes and/or methods disclosed in the “The Coiled Implant Application.”

While various embodiments have been described, the description is intended to be exemplary, rather than limiting, and it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible that are within the scope of the embodiments. Although many possible combinations of features are shown in the accompanying figures and discussed in this detailed description, many other combinations of the disclosed features are possible. Any feature of any embodiment may be used in combination with or substituted for any other feature or element in any other embodiment unless specifically restricted. Therefore, it will be understood that any of the features shown and/or discussed in the present disclosure may be implemented together in any suitable combination. Accordingly, the embodiments are not to be restricted except in light of the attached claims and their equivalents. Also, various modifications and changes may be made within the scope of the attached claims.