Patent Description:
The disclosure relates to the field of medical devices. More particularly, the disclosure relates to the field of orthopedic medical devices. Specific examples relate to bone plates for internal fixation of fractures. The disclosure also relates to bone plate systems, methods of treatment, and methods of manufacturing.

Bone plates have been widely used for internal fixation of fractures for years. Indeed, various bone plate structures are known in the art. For example, some conventional bone plates are constructed from either metal, such as titanium alloys and stainless steel, or polymers, such as carbon fiber or polyethertherketone ("PEEK").

While conventional bone plates are widely used, they do have several drawbacks. For example, while metal plates typically demonstrate adequate wear resistance and strength, conventional solid metal construction hinders a user's ability to visualize the fracture site while using X-ray imaging techniques and equipment. Titanium plates often require the use of a computed tomography (CT) scan to image a fracture site when assessing healing of the bone, which exposes a patient to a higher level of radiation than that involved in a standard X-ray. Moreover, while carbon fiber and PEEK bone plates provide an option for increased visibility of the fracture site using standard X-ray imaging, these plates must be significantly thicker than metal bone plates to achieve desirable strength. Furthermore, PEEK bone plates can also be entirely transparent, which creates additional challenges when attempting to visualize the position of the plate in post-operative evaluations.

<CIT> discloses a bone fixation plate comprising a main body formed of a first material and a support member formed of a second, different material and attached to the main body.

A need exists, therefore, for improved bone plates, and methods of manufacturing bone plates.

Claim <NUM> relates to method of manufacturing the bone plate of claim <NUM>.

Associated methods of treatment are also described herein to aid understanding of the invention.

The embodiments which form part of the invention are illustrated in <FIG> and <FIG>. The examples shown in the other figures do not form part of the invention but represent background that is useful for understanding the invention.

Various methods of manufacturing a bone plate are also described.

An example method of manufacturing comprises forming a main body having a porous portion and a non-porous portion such that the main body defines a plurality of passageways, each of which is bounded at least partially by the porous portion.

Another example method of manufacturing a bone plate comprises 3D printing (not claimed) a main body having a porous portion and a non-porous portion such that the main body defines a plurality of passageways, each of which is bounded at least partially by the porous portion, and a cavity. Another step comprises disposing a support member in the cavity. In one example method, this is accomplished by injection molding the support member into the cavity such that the polymeric material of the support member extends into the passageways of the porous portion of the main body that bounds each of the passageways. In another example, this is accomplished by 3D printing the support member onto the main body such that the support member abuts the porous portion of the main body that bounds each of the passageways. In this example, the support member can be formed to include its own porous portion, such as a porous portion that forms a part of the lower surface of the bone plate that will contact the bone when placed across a fracture in the bone. In another example, this is accomplished by 3D printing the support member simultaneously with the 3D printing of the main body. In this example, the support member can be formed to include its own porous portion, such as a porous portion that forms a part of the lower surface of the bone plate that will contact the bone when placed across a fracture in the bone.

Additional understanding of the inventive bone plates, bone plate systems, methods of treatment, and methods of manufacturing can be obtained by reviewing the detailed description of selected examples, below, with reference to the appended drawings.

The following detailed description and the appended drawings describe and illustrate various example bone plates, bone plate systems, methods of treatment, and methods of manufacturing a bone plate. The description and drawings are provided to enable one skilled in the art to make and use one or more example bone plates and bone plate systems, and to perform one or more example methods of treatment and methods of manufacturing a bone plate. They are not intended to limit the scope of the claims in any manner.

As used herein, the term "porous," and grammatically related terms, refers to a macro structural configuration of a component or portion of a component in which the material of the component or portion of a component defines a series of passageways into which material, such as a liquid, can enter. The passageways can be randomly distributed throughout the component or portion of a component, or can be distributed throughout the component or portion of a component in an ordered fashion. As an example, a lattice structure created during 3D printing of a metal component or portion of a metal component provides a porous structure consistent with this definition of "porous. " The term does not include micro structural pores that naturally occur in the material that comprises the component or portion of a component.

As used herein, the term "non-porous," and grammatically related terms, refers to a macro structural configuration of a component or portion of a component in which the material of the component or portion of a component does not define a series of passageways into which material, such as a liquid, can enter.

<FIG> and <FIG> illustrate an example bone plate <NUM>. The bone plate <NUM> has a main body <NUM> having a first end <NUM>, a second end <NUM>, and a lengthwise axis <NUM> extending between the first end <NUM> and the second end <NUM>. The main body <NUM> has first <NUM> and second <NUM> opposing surfaces, and defines a plurality of passageways <NUM>. Each passageway 120a, 120b, 120c, 120d, 120e, 120f, <NUM> of the plurality of passageways <NUM> extends through the entire thickness of the main body <NUM>, from the first surface <NUM> to the second surface <NUM>. As such, each passageway 120a, 120b, 120c, 120d, 120e, 120f, <NUM> provides a through opening within which another component can be disposed, such as a bone screw useful in securing the bone plate <NUM> across a fracture in a bone as part of a fixation procedure.

The main body <NUM> defines a circumferential wall 122a, 122b, 122c, 122d, 122e, 122f, <NUM> for each passageway 120a, 120b, 120c, 120d, 120e, 120f, <NUM> of the plurality of passageways <NUM>. Each circumferential wall 122a, 122b, 122c, 122d, 122e, 122f, <NUM> bounds a respective passageway 120a, 120b, 120c, 120d, 120e, 120f, <NUM>.

The main body <NUM> includes a non-porous portion <NUM> and a porous portion <NUM>. In the illustrated example, the non-porous portion <NUM> is a continuous portion of the main body <NUM>, while the porous portion <NUM> comprises a plurality of discrete porous portions 150a, 150b, 150c, 150d, 150e, 150f, <NUM>. Each circumferential wall 122a, 122b, 122c, 122d, 122e, 122f, <NUM> is cooperatively formed by the non-porous portion <NUM> and one of the discrete porous portions 150a, 150b, 150c, 150d, 150e, 150f, <NUM>. As best illustrated in <FIG> and <FIG>, circumferential wall <NUM> is recessed within passageway <NUM>, providing a countersink structure for screw <NUM>. Non-porous portion <NUM> of the main body <NUM> defines the upper portion <NUM> of the circumferential wall <NUM>, while porous portion <NUM> defines the lower portion <NUM> of the circumferential wall <NUM>. The lower portion <NUM> forms a part of the lower surface <NUM> of the main body <NUM>. Thus, in this embodiment, lower surface <NUM> is cooperatively formed by the non-porous portion <NUM> and the porous portion <NUM>, via discrete porous portions 150a, 150b, 150c, 150d, 150e, 150f, <NUM>.

This structural configuration of the circumferential wall <NUM> is considered advantageous at least because it positions the porous portion <NUM> of the circumferential wall <NUM> beneath the non-porous portion <NUM> of the circumferential wall <NUM> with respect to the opposing surfaces <NUM>, <NUM>. As best illustrated in <FIG>, with respect to passageway <NUM>, this enables the thread <NUM> of screw <NUM> to deform the structure of the porous portion <NUM> as the screw <NUM> is driven into the passageway <NUM>, effectively forming a thread in the porous portion <NUM> that mates with the thread <NUM> of the screw <NUM>. The non-porous portion <NUM> ensures that the head <NUM> of the screw <NUM> does not pass through the opening, as the non-porous portion <NUM> will resist the deformation that the porous portion <NUM> permits.

In the illustrated example, each circumferential wall 122a, 122b, 122c, 122d, 122e, 122f, <NUM> has a similar structure to that described above for circumferential wall <NUM>, with porous portion 150a, 150b, 150c, 150d, 150e, 150f, <NUM> beneath the non-porous portion <NUM> with respect to the opposing surfaces <NUM>, <NUM>. It is noted, though, that bone plates according to other examples can include circumferential walls having different structures. For example, it may be desirable to include one or more circumferential walls having a thread that is fully formed by the non-porous portion of a bone plate according to an embodiment in addition to a circumferential wall having the structural configuration described above. Inclusion of such a circumferential ensures that at least one thread is available that does not require thread forming action by a screw during placement of the bone plate, which may be desirable. Inclusion of at least one circumferential wall having the structural configuration described and illustrated above is considered advantageous at least because it ensures that at least one screw will be installed with thread forming action, providing desirable securement and bony ingrowth properties for the bone plate.

A bone plate according to an embodiment can include any suitable number of passageways. A skilled artisan will be able to select an appropriate number of passageways for a bone plate according to a particular embodiment based on various considerations, including the anatomical location at which the bone plate is intended to be used. The inclusion of seven passageways in the bone plate <NUM> illustrated in <FIG> is merely an example of a suitable number of passageways. Similarly, a bone plate according to an embodiment can have any suitable overall shape. A skilled artisan will be able to select an appropriate shape for a bone plate according to a particular embodiment based on various considerations, including the anatomical location at which the bone plate is intended to be used. The elongate strip shape of the bone plate <NUM> illustrated in <FIG> is merely an example of a suitable overall shape.

The porous portion in a bone plate according to a particular embodiment can have any suitable dimensions, and a skilled artisan will be able to select appropriate dimensions for a porous portion in a bone plate according to a particular embodiment based on various considerations, including the function of the porous portion. For example, in embodiments in which the porous portion forms a portion of the circumferential wall bounding a screw passageway and is to deform in response to a screw being driven through the passageway, the inventors have determined that a porous portion having a thickness of between about <NUM> and <NUM> is suitable for a passageway having an inner diameter of <NUM>. In embodiments in which the porous portion forms a boundary for a cavity into which a support member is to be formed, such as by injection molding, the inventors have determined that a porous portion having a thickness of between about <NUM> and <NUM> is suitable.

<FIG> illustrates another example bone plate <NUM>. The bone plate <NUM> is similar to the bone plate <NUM> illustrated in <FIG> and described above, except as detailed below. Thus, bone plate <NUM> has a main body <NUM> having a first end <NUM>, a second end <NUM>, and a lengthwise axis <NUM> extending between the first end <NUM> and the second end <NUM>. The main body <NUM> has first <NUM> and second <NUM> opposing surfaces, and defines a plurality of passageways <NUM>. For illustrative purposes only, the bone plate <NUM> is positioned in the opposite orientation of the bone plate <NUM> in <FIG>, such that the second surface <NUM> is upright and the first surface <NUM> is downward. Each passageway 220a, 220b, 220c of the plurality of passageways <NUM> extends through the entire thickness of the main body <NUM>, from the first surface <NUM> to the second surface <NUM>. As such, each passageway 220a, 220b, 220c provides a through opening within which another componentcan be disposed, such as a bone screw useful in securing the bone plate <NUM> across a fracture in a bone as part of a fixation procedure.

The main body <NUM> defines a circumferential wall 222a, 222b, 222c for each passageway 220a, 220b, 220c of the plurality of passageways <NUM>. Each circumferential wall 222a, 222b, 222c bounds a respective passageway 220a, 220b, 220c.

The main body <NUM> includes a non-porous portion <NUM> and a porous portion <NUM>. The non-porous portion <NUM> is a continuous portion of the main body <NUM>. In this example, and in contrast to first example bone plate <NUM>, porous portion <NUM> is also a continuous portion of the main body <NUM>. Each circumferential wall 222a, 222b, 222c is cooperatively formed by the non-porous portion <NUM> and the porous portion <NUM>. Each circumferential wall 222a, 222b, 222c is recessed within a respective passageway 220a, 220b, 220c, providing a countersink structure for a bone screw. Non-porous portion <NUM> of the main body <NUM> defines the upper portion 224a, 224b, 224c of each circumferential wall 222a, 222b, 222c, while porous portion <NUM> defines the lower portion 226a, 226b, 226c of each circumferential wall 222a, 222b, 222c. The lower portion 226a, 226b, 226c of each circumferential wall 222a, 222b, 222c is continuous and flush with the lower surface <NUM> of the main body <NUM>. Lower surface <NUM> is cooperatively formed by the non-porous portion <NUM> and the porous portion <NUM>. In this example, non-porous portion <NUM> forms a perimeter edge <NUM> of the lower surface <NUM>.

This structural configuration is considered advantageous at least because it provides the desirable thread forming capability of the porous portion <NUM> in the passageways while also positioning the porous portion <NUM> on the majority of the lower surface <NUM> of the main body <NUM>, which is the bone-contacting surface of the bone plate <NUM>. The porous structure of the porous portion <NUM> provides structure that is advantageous for bony ingrowth following securement of the bone plate <NUM> to a bone. Taken together, the thread forming capability provided by the porous portion <NUM> positioned within the passageways 220a, 220b, 220c and the advantageous bony ingrowth structure provided by the porous portion positioned on the majority of the lower surface <NUM>, the porous portion <NUM> provides desirable securement properties for the bone plate <NUM>.

The porous portion can comprise any suitable portion of the lower surface in a bone plate according to a particular embodiment, and a skilled artisan will be able to select a suitable portion, based on percentage of total surface area of the lower surface, for a bone plate according to a specific embodiment based on various considerations, including the anatomical location at which the bone plate is intended to be used. Examples of suitable percentages of total surface area of the lower surface that the porous portion comprises include, but are not limited to, at least about <NUM>% of the total surface area of the lower surface, greater than <NUM>% of the total surface area of the lower surface, between about <NUM>% and about <NUM>% of the total surface area of the lower surface, between about <NUM>% and about <NUM>% of the total surface area of the lower surface, between about <NUM>% and about <NUM>% of the total surface area of the lower surface, and between about <NUM>% and about <NUM>% of the total surface area of the lower surface.

While the bone plate illustrated in <FIG> and the bone plate <NUM> illustrated in <FIG> are monolithic structures, bone plates according to some examples include multiple components. Indeed, hybrid bone plates, which include components of different materials, such as a metal component and a polymeric component, provide certain advantages, as described below.

<FIG> illustrates another example bone plate <NUM>. Bone plate <NUM> has a main body <NUM> and a support member <NUM>. Main body <NUM> defines a cavity <NUM> in which support member <NUM> is disposed.

Main body <NUM> has a first end <NUM>, a second end <NUM>, and a lengthwise axis <NUM> extending between the first end <NUM> and the second end <NUM>. The main body <NUM> has first <NUM> and second <NUM> opposing surfaces. The main body <NUM> and support member <NUM> cooperatively define a plurality of passageways <NUM>. Each passageway 320a, 320b, 320c of the plurality of passageways <NUM> extends through the entire thickness of the bone plate <NUM>, from the first surface <NUM> to the second surface <NUM>. As such, each passageway 320a, 320b, 320c provides a through opening within which another component can be disposed, such as a bone screw useful in securing the bone plate <NUM> across a fracture in a bone as part of a fixation procedure.

The main body <NUM> and support member <NUM> cooperatively define a circumferential wall 322a, 322b, 322c for each passageway 320a, 320b, 320c of the plurality of passageways <NUM>. Each circumferential wall 322a, 322b, 322c bounds a respective passageway 320a, 320b, 320c.

The main body <NUM> includes a non-porous portion <NUM> and a porous portion <NUM>. The non-porous portion <NUM> is a continuous portion of the main body <NUM> while the porous portion <NUM> comprises a plurality of discrete porous portions 350a, 350b, 350c. Each circumferential wall 322a, 322b, 322c is cooperatively formed by the non-porous portion <NUM>, one of the discrete porous portions 350a, 350b, 350c, and the support member <NUM>. Each circumferential wall 322a, 322b, 322c is recessed within a respective passageway 320a, 320b, 320c, providing a countersink structure for a bone screw. Non-porous portion <NUM> of the main body <NUM> defines the upper portion <NUM> of each circumferential wall 322c, while the support member <NUM> defines the lower portion <NUM> of the circumferential wall 322c. Porous portion 350c provides an intermediate 328c portion of the circumferential wall 322a. In this example, lower surface <NUM> is cooperatively formed by the non-porous portion <NUM> of the main body <NUM>, the porous portions 350a, 350b, 350c of the main body <NUM>, and the support member <NUM>.

In this example, the porous portion <NUM> provides boundaries for the cavity <NUM> of the main body <NUM>. This is particularly advantageous for bone plates in which the support member is formed by injection molding, as the porous portion <NUM> permits polymer to enter the passageways of the porous portion, enhancing fixation between the main body <NUM> and support member <NUM>. Furthermore, positioning of the porous portion <NUM> in the circumferential walls 322a, 322b, 322c also provides the thread forming capability described above, providing additional advantage to this structural configuration.

Alternatively, as illustrated in <FIG>, the support member <NUM>' can abut the porous portion <NUM>' of the main body <NUM>, such that the polymer of the support member <NUM>' does not extend into the passageways of the porous portion <NUM>'. Also alternatively, support member <NUM>' can include a porous portion <NUM>' as well. In this alternative example, porous portion <NUM>' of the support member <NUM>' forms a portion of lower surface <NUM>', providing beneficial bony ingrowth properties for the bone plate <NUM>'. This structural configuration is considered particularly advantageous for bone plates in which the support member is formed by 3D printing, either onto the main body or simultaneously with the main body.

<FIG>, <FIG>, and <FIG> illustrate a bone plate <NUM> according to the invention. The bone plate <NUM> is similar to the bone plate <NUM> illustrated in <FIG> and described above, except as detailed below. Thus, bone plate <NUM> has a main body <NUM> having a first end <NUM>, a second end <NUM>, and a lengthwise axis <NUM> extending between the first end <NUM> and the second end <NUM>. The main body <NUM> has first <NUM> and second <NUM> opposing surfaces, and defines a plurality of passageways <NUM>. Each passageway 420a, 420b, 420c, 420d, 420e, 420f of the plurality of passageways <NUM> extends through the entire thickness of the main body <NUM>, from the first surface <NUM> to the second surface <NUM>. As such, each passageway 420a, 420b, 420c, 420d, 420e, 420f provides a through opening within which another component can be disposed, such as a bone screw useful in securing the bone plate <NUM> across a fracture in a bone as part of a fixation procedure. Main body <NUM> defines a cavity <NUM> in which support member490 is disposed. Support member <NUM> defines a circumferential wall 422a, 422b, 422c, 422d, 422e, 422f for each passageway 420a, 420b, 420c, 420d, 420e, 420f of the plurality of passageways <NUM>. Each circumferential wall 422a, 422b, 422c, 422d, 422e, 422f bounds a respective passageway 420a, 420b, 420c, 420d, 420e, 420f. As best illustrated in <FIG>, lower surface <NUM> is cooperatively formed by the main body <NUM> and the support member <NUM>. Upper surface <NUM> of main body <NUM> defines first 430a and second 432a depressions disposed adjacent passageway 420a, first 430b and second 432b depressions disposed adjacent passageway 420b, first 430c and second 432c depressions disposed adjacent passageway 420c, first 430d and second 432d depressions disposed adjacent passageway 420d, first 430e and second 432e depressions disposed adjacent passageway 420e, and first 430f and second 432f depressions disposed adjacent passageway 420f.

In this embodiment, main body <NUM> defines an upper circumferential recess and a lower circumferential recess around each passageway 420a, 420b, 420c, 420d, 420e, 420f of the plurality of passageways <NUM>. <FIG> and <FIG> illustrate the upper circumferential recess 442c and the lower circumferential recess 444c that are disposed around passageway 420c. In this example, an upper circumferential recess that is identical to upper circumferential recess 442c and a lower circumferential recess that is identical to lower circumferential recess 442d is disposed around each of the other passageways 420a, 420b, 420d, 420e, 420f defined by the main body <NUM>, but are not visible in the drawings.

In the illustrated embodiment, the upper circumferential recess 442c extends radially inward from the central axis of the passageway 420c and generally in an upward direction toward the upper surface <NUM> of the main body <NUM>. The lower circumferential recess 444c also extends radially inward from the central axis of the passageway 420c and generally in an upward direction toward the upper surface <NUM> of the main body <NUM>. The lower circumferential recess 444c extends further radially inward relative to the central axis of the passageway 420c than the upper circumferential recess 442c.

Main body <NUM> defines first 446c and second 448c circumferential projections that are disposed between the upper circumferential recess 442c and lower circumferential recess 444c. In this example, first and second projections that are identical to first 446c and second 448c projections are disposed around each of the other passageways 420a, 420b, 420d, 420e, 420f defined by the main body <NUM>, but are not visible in the drawings. As best illustrated in <FIG> and <FIG>, the inclusion and structural arrangement of first 446c and second 448c projections accommodates the thread <NUM> of a bone screw <NUM> disposed through the passageway 420c at multiple angles relative to the central axis of the passageway 420c, such as a coaxial arrangement illustrated in <FIG> and an arrangement in which the bone screw <NUM> is disposed through the passageway 420c at an angle to the central axis of the passageway 420c, as illustrated in <FIG>. The inclusion and structural arrangement of first 446c and second 448c projections also provides a structure against which the support member <NUM> can be urged during insertion of the bone screw <NUM>.

As indicated above, support member <NUM> defines a circumferential wall 422a, 422b, 422c, 422d, 422e, 422f for each passageway 420a, 420b, 420c, 420d, 420e, 420f of the plurality of passageways <NUM>. As best illustrated in <FIG> and <FIG>, the first 446c and second 448c projections are disposed entirely within the support member <NUM>. This structural arrangement allows the thread <NUM> of a bone screw <NUM> to extend into the support member when the bone screw <NUM> is disposed through the passageway 420c, as illustrated in <FIG> and <FIG>. The material is the support member <NUM> is relatively softer than the material of the main body <NUM>, allowing the support member <NUM> to be disrupted upon entry of the thread <NUM>. This structural arrangement and composition of the circumferential wall 422c, along with the presence and structural arrangement of the first 446c and second 448c projections, provides for desirable engagement with the thread <NUM> of a bone screw <NUM>. In one particular example, the second projection disposed around each passageway comprises a circumferential thread itself, which is considered particularly advantageous at least because it further enhances the engagement of a bone screw passed through the passageway.

It is noted that, while not illustrated in <FIG>, <FIG>, and <FIG> does not include a porous portion, bone plate <NUM> can include one or more porous portions, as described in detail above in connections with example bone plate <NUM>, <NUM>, <NUM>, and <NUM>', for example.

Bone plates according to embodiments can be made from any material suitable for use in medical devices intended for orthopedic use, including use as a long-term implant. Examples of suitable materials include metals, metal alloys, and polymeric materials. Inclusion of a porous portion is critical to achieving the desired properties of the inventive bone plates. Accordingly, use of a material that enables formation of a porous portion using appropriate techniques is appropriate. Examples of suitable materials for which appropriate porous portions can be formed using conventional techniques, such as 3D printing, include, but are not limited to, Titanium, Magnesium, and other suitable materials. Examples of suitable metal alloys include stainless steel (<NUM>), cobalt alloys, pure titanium, titanium alloys, magnesium alloys, molybdenum alloys, zirconium alloys, Ti6Al4V, <NUM> LVM, <NUM>. 4441Ti-13Nb-13Zr, Ti-12Mo-6Zr-2Fe, Ti-15Mo-5Zr-3Al, Ti15Mo, Ti-35Nb-7Zr-5Ta and Ti-29Nb-13Ta-<NUM>. 6Zr Ti-6Al-7Nb and Ti-15Sn-4Nb-2Ta-<NUM>. 2Pd Co-Cr-Mo alloys.

Non-metal materials are also considered suitable for use in bone plates according to embodiments, both as a main body component and, if included, as a support member component. Examples of suitable non-metal materials include polymeric materials, including plastic metals currently considered suitable for use in medical devices, carbon fiber, polyaryletherketone (PAEK), polyether ether ketone (PEEK), PEEK (<NUM>, <NUM>, I2, I4), Polyamid, PA66, carbon fiber reinforced polyaryletherketone (CFR PAEK), polyethere ketone ketone (PEKK), carbon fiber reinforced polyether ketone ketone (CFR PEKK), carbon fiber reinforced polyether ether ketone (CFR PEEK), CFR PEEK (<NUM> CA30, <NUM> CA20, <NUM> CA30, <NUM> CA20 , I2 CF20, I2 CF30, I4 CF30, I4 CF20), Polyamid CFR, PA66 CFR, and any other materials considered suitable for a bone plate. The inventors have determined that, for embodiments in which the support member includes carbon fiber, it is considered advantageous to include carbon fiber in the material of the support member at an amount that represents a balance between the desirable strength carbon fiber provides and any offsets it contributes to the contourability of the bone plate due to the brittleness of the material. For plates that include a support member comprising carbon fiber reinforced polyether ether ketone (CFR PEEK), it is considered advantageous to include carbon fiber in PEEK at an amount that is less than <NUM>% on a volume basis. It is also considered advantageous to include carbon fiber in PEEK at an amount that is less than <NUM>% on a volume basis. It is also considered advantageous to include carbon fiber in PEEK at an amount that is less than <NUM>% on a volume basis. It is also considered advantageous to include carbon fiber in PEEK at an amount that is less than <NUM>% on a volume basis. It is also considered advantageous to include carbon fiber in PEEK at an amount that is less than <NUM>% on a volume basis.

<FIG> illustrates according to the invention a bone plate system <NUM>. The bone plate system <NUM> includes a bone plate <NUM> according to an embodiment, such as the examples described and illustrated herein, and a plurality of bone screws <NUM>. The plurality of bone screws <NUM> includes a number of bone screws that is at least the same as the number of passageways in the bone plate <NUM>. Also, each bone screw of the plurality of bone screws <NUM> is adapted to be disposed in one of the passageways of the bone plate <NUM>. The bone plate <NUM> and the plurality of bone screws <NUM> can be disposed within or on a container <NUM>. One or more documents <NUM> containing instructions for using the bone plate <NUM> and plurality of bone screws <NUM> together can be included in the container <NUM>.

<FIG> is a flowchart representation of an example method of treatment <NUM> (not being part of the invention). The method <NUM> is suitable for treatment of a bone fracture. A first step <NUM> comprises placing a bone plate according to an embodiment across a fracture in a bone such that the lower surface of the bone plate is in contact with the bone. A second step <NUM> comprises driving a bone screw through a passageway of the bone plate such that the thread of the bone screw deforms the porous portion of the bone plate that comprises a portion of the circumferential wall of the passageway to form a mating thread in the circumferential wall. The second step can be repeated a suitable number of times until a bone screw is driven through each passageway of the bone plate and into the bone.

<FIG> is a flowchart representation of an example method of manufacturing a bone plate <NUM>. A first step <NUM> comprising 3D printing a main body having a porous portion and a non-porous portion such that the main body defines a plurality of passageways, each of which is bounded at least partially by the porous portion, and a cavity. A second step <NUM> comprises disposing a support member in the cavity. In one example, the second step <NUM> is accomplished by injection molding the support member into the cavity such that the polymeric material of the support member extends into the passageways of the porous portion of the main body that bounds each of the passageways. In another example, the second step <NUM> is accomplished by 3D printing the support member onto the main body such that the support member abuts the porous portion of the main body that bounds each of the passageways. In this example, the support member can be formed to include its own porous portion, such as a porous portion that forms a part of the lower surface of the bone plate that will contact the bone when placed across a fracture in the bone. In another example, the second step <NUM> is accomplished by 3D printing the support member simultaneously with the 3D printing of the main body. In this example, the support member can be formed to include its own porous portion, such as a porous portion that forms a part of the lower surface of the bone plate that will contact the bone when placed across a fracture in the bone.

<FIG> is a flowchart representation, according to the invention of a method of manufacturing a bone plate <NUM>. A first step <NUM> comprises forming a bone plate precursor that includes a main body that defines a plurality of passageways, each of which is blocked by a sacrificial wall, and a cavity. <FIG> illustrates an example bone plate precursor <NUM> formed by performance of step <NUM>. The bone plate precursor <NUM> includes a plurality of passageways <NUM>, each passageway 920a, 920b, 920c, 920d, 920e, 920f of the plurality of passageways <NUM> is blocked by a sacrificial wall 938a, 938b, 938c, 938d, 938e, 938f. In one example, the first step <NUM> is accomplished by 3D printing the bone plate precursor <NUM>. In one particularly advantageous method, the first step is performed such that the bone plate precursor <NUM> is formed to have a pair of depressions 930a, 932a, 930b, 932b, 930c, 932c, 930d, 932d, 930e, 932e, 930f, 932f formed in an upper surface <NUM> of the main body <NUM> adjacent to each passageway 920a, 920b, 920c, 920d, 920e, 920f of the plurality of passageways <NUM>.

A second step <NUM> comprises disposing a support member in the cavity of the bone plate precursor to form a bone plate intermediate that includes a main body that defines a plurality of passageways, each of which is blocked by a sacrificial wall, and a cavity, and a support member disposed within the cavity such that the support member abuts each of the sacrificial walls. <FIG> illustrates an example bone plate intermediate <NUM> formed by performance of step <NUM>. The bone plate intermediate <NUM> includes a main body <NUM> that defines a plurality of passageways (not visible in the figure), each passageway of which is blocked by a sacrificial wall (not visible in the figure), and a cavity <NUM>, and a support member <NUM> disposed within the cavity <NUM> such that the support member <NUM> abuts each of the sacrificial walls. In one example, the second step <NUM> is accomplished by injection molding the support member <NUM> into the cavity <NUM> of a bone plate precursor, such as bone plate precursor <NUM>. In another example, the second step <NUM> is accomplished by 3D printing the support member onto the bone plate precursor. In another example, the second step <NUM> is accomplished by 3D printing the bone plate precursor simultaneously with the 3D printing of the support member.

Claim 1:
A bone plate (<NUM>, <NUM>), comprising:
a main body (<NUM>, <NUM>, <NUM>) formed of a first material and having a first surface (<NUM>) and a second surface (<NUM>) opposite the first surface, the main body (<NUM>, <NUM>, <NUM>) defining a plurality of main body openings, a plurality of main body circumferential walls, and a cavity (<NUM>, <NUM>) that is continuous with the plurality of main body openings, each main body circumferential wall bounding a main body opening of the plurality of main body openings and defining a first circumferential recess (442c) and a second circumferential recess (444c) disposed around each main body opening of the plurality of main body openings; and
a support member (<NUM>, <NUM>) formed of a second, different material and disposed in the cavity (<NUM>, <NUM>) of the main body (<NUM>, <NUM>, <NUM>), the support member (<NUM>, <NUM>) defining a plurality of support member openings and a plurality of support member circumferential walls (422a-f), each support member circumferential wall (422a-f) bounding a support member opening of the plurality of support member openings, a portion of the support member (<NUM>, <NUM>) disposed in the first circumferential recess (442c) and the second circumferential recess (444c) of each main body opening of the plurality of main body openings;
wherein each main body opening of the plurality of main body openings is coaxial with a support member opening of the plurality of support member openings to form a passageway (<NUM>, 420a-f, <NUM>, 920a-f, 1020a) partially bounded by a main body circumferential wall of the plurality of main body circumferential walls and a support member circumferential wall (422a-f) of the plurality of support member circumferential walls (422a-f).