Tissue implant and uses thereof

Abstract

Provided herein are methods and devices for the implantation of tissue implant to repair osteochondral or chondral defects.

Description

[0001] WSGR Docket No. 52715-711.601

[0002] TISSUE IMPLANT AND USES THEREOF

[0003] CROSS REFERENCE

[0004]

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 716,542, filed on November 5, 2024, which is incorporated herein by reference in its entirety.

[0005] BACKGROUND

[0006]

[0002] Tissue implants are vital in regenerative medicine for the repair of damaged tissues. The disclosed implant is designed to mimic natural tissue properties and promote cell attachment and growth. Focal and full-thickness cartilage lesions can be a significant source of pain and impairment to a patient's quality of life. Over 250,000 patients undergo surgical treatment for cartilage lesions each year, which is often associated with a low rate of treatment success (-60% treatment failure) due to the complex nature of the tissue. The present disclosure aims to address the limitations of current treatments by enhancing the safety, adaptability, durability and ease of use.

[0007] SUMMARY

[0008]

[0003] There is an unmet need for improving clinical outcomes with a more mechanically and biologically stable implant, while also addressing manufacturing costs. This application provides meets this unmet need by providing devices and methods directed towards tissue implants and methods of implantation.

[0009]

[0004] In one aspect, provided herein is a tissue implant comprising: a first region comprising a plurality of layers arranged in a lattice structure, the plurality of layers comprising a bottom layer, a plurality of middle layers, and a top layer, wherein the plurality of layers has an infill density of at least about 20%; and a second region having at least one layer with an infill density of at least about 75%, adjacent to the top layer of the first region. In some embodiments, the infill density of the first region of the tissue implant may be from about 50% to about 65%. In some embodiments, the infill density of the first region can range from about 55% to about 60%. In some embodiments, the infill density of the first region may be about 58%. In some embodiments, the infill density of the second region can range from about 85% to about 100%. In some embodiments, the infill density of the second region can be about 90%. In some embodiments, each layer of the first region may have a thickness ranging from about 0.05 mm to about 1 mm. In some embodiments, each layer of the first region can be about 0.2 mm in thickness. In some embodiments, the at least one layer of the second region can have a thickness ranging from about 0.1 mm to about 0.4 mm. In some embodiments, the single layer of the WSGR Docket No. 52715-711.601 second region can be about 0.2 mm in thickness. In some embodiments, each layer of the plurality of layers of the first region may be composed of a polymer material. In some embodiments, the at least one layer of the second region can be composed of a polymer material. In some embodiments, the polymer material may comprise a thermoplastic polymer. In some embodiments, the thermoplastic polymer can comprise resorbable materials. In some embodiments, the thermoplastic polymer may comprise non-resorbable materials.

[0010]

[0005] In some embodiments, the polymer material can comprise polyvinyl alcohol (PVA). In some embodiments, the polymer material can comprise greater than about 30% PVA. In some embodiments, each layer of the plurality of the layers of the first region may be arranged in a discontinuous unidirectional or continuous serpentine configuration. In some embodiments, each layer of the plurality of the layers of the first region can be at a rotational offset relative to an adjacent layer. In some embodiments, the rotational offset can be from about 5 to about 175 degrees. In some embodiments, the at least one layer of the second region may comprise a reinforcing circumferential ring outlining a perimeter of the second region. In some embodiments, the at least one layer of the second region can be arranged in a linear, a serpentine, or a radial configuration. In some embodiments, the tissue implant can be sized and shaped for implantation into an articular surface of bone. In some embodiments, the tissue implant may be cylindrical in shape. In some embodiments, the implant can be at least about 10 mm in diameter. In some embodiments, the implant may be from about 10 mm to about 20 mm in diameter. In some embodiments, the tissue implant can be from about 2 mm to about 10 mm in thickness. In some embodiments, the tissue implant may be about 4 mm in thickness. In some embodiments, the tissue implant may have a compressibility of at least about 200 1 / kPa. In some embodiments, the first region can have a porosity of at least about 58%. In some embodiments, the bottom layer and a periphery of the first region may comprise a porosity configured to engraftment of the tissue implant into the tissue. In some embodiments, the bottom layer and at least an adjacent layer of the plurality of middle layers can be non-continuous layers defining a cylindrical pocket disposed within the first region. In some embodiments, the cylindrical pocket may be configured to accept a bone post in the tissue. In some embodiments, the tissue implant can further comprise a third region having a ring-like structure and disposed along the outer circumference of the tissue implant. In some embodiments, the third region may have an infill density of about 100%. In some embodiments, the third region can be composed of a polymer material. In some embodiments, the third region may be composed of the same polymer material as the first region and the second region. In some embodiments, the polymer material can be a composite of nylon 12 and PVA. WSGR Docket No. 52715-711.601

[0011]

[0006] In some embodiments, the third region of the tissue implant may be integrated with the tissue implant. In some embodiments, the third region can be at least about 0.5 mm in thickness. In some embodiments, the third region may be about 1 mm in thickness. In some embodiments, the third region can comprise a press-fit ring configured to hold the implant in a tissue cavity. In some embodiments, the third region may comprise two press-fit rings. In some embodiments, the two press-fit rings may be separated by a distance of at least 0.05mm. In some embodiments, the third region can comprise a press-fit ring disposed at or near the bottom layer of the first region of the tissue implant. In some embodiments, the press-fit ring disposed at or near the bottom layer of the first region of the tissue implant may have a beveled edge. In some embodiments, the tissue implant can be configured to be compressed to fit into a tissue cavity, and to expand after implantation such that the press-fit ring engages with a surface of the tissue cavity and holds the tissue implant in place. In some embodiments, the third region can be at least about 1 mm larger in diameter than a diameter of the tissue cavity. In some embodiments, the third region of the tissue implant may have a higher rigidity than the first region. In some embodiments, the first region of the tissue implant can have an elastic modulus comparable to native cartilage.

[0012]

[0007] In some embodiments, an elastic modulus of the first region can be from about 200 kPa to about 0.5 GPa. In some embodiments, an elastic modulus of the third region can be from about 200 kPa to about 4 GPa. In some embodiments, the tissue implant may be configured to be implanted into a tissue by arthroscopic implantation or by a mini-open procedure. In some embodiments, the tissue implant can be an osteochondral implant. In some embodiments, the tissue implant may be configured to withstand mechanical loading of 334N for 20,000 cycles. In some embodiments, the average pull-out force of the tissue implant, when implanted into a tissue cavity, can be greater than 20 N. In some embodiments, the tissue implant may be configured to be implanted into the articular surface of the trochlea. In some embodiments, the tissue implant can be configured to be implanted into the articular surface of the medial condyle. In some embodiments, the tissue implant may be configured to be implanted into the articular surface of the lateral condyle.

[0013]

[0008] In some embodiments, the tissue implant may have a shelf-life of at least 12 months when stored in water at a room temperature. In some embodiments, the tissue implant may be used in a method of treating a tissue defect in a subject. In some embodiments, the tissue defect treated by this method may be a critical-sized tissue defect. In some embodiments, the tissue defect treated can be an osteochondral defect or a chondral defect. In some embodiments, the method may be applied if the subject has damaged knee articular cartilage with osteoarthritis graded as Kellgren-Lawrence 0-3. In some embodiments, the subjects treated with the tissue WSGR Docket No. 52715-711.601 implant can have medial or lateral femoral condyle and / or trochlea articular cartilage lesions of about 4 cm2 or less. In some embodiments, the subjects treated with the tissue implant may have a Visual Analog Scale (VAS) score of greater than or equal to 30 mm pain and less than or equal to 100 mm at baseline. In some embodiments, the tissue defect treated by the tissue implant can have an International Cartilage Repair Society (ICRS) of less than or equal to Grade 3C. In some embodiments, the subject treated with the tissue implant may not have one of the following conditions or treatments: rheumatoid arthritis, inflammatory joint disease, avascular necrosis, osteoarthritis Grade 4 according to Kellgren-Lawrence grading, flexion contracture of more than 10 degrees, more than 8 degrees of physiologic vagus or varus based on leg length (hip to ankle) AP weight bearing x-ray, prior arthroscopy within 3 months prior to the implanting for joint lavage, chondral debridement, and / or loose body removal, meniscal transplantation within 6 months prior to the implanting, ligamentous repair or malalignment correction within 6 months prior to the implanting, treated for cartilage repair prior to the implanting, intra-articular steroid therapy or intra-articular hyaluronic acid therapy within 6 months prior to the implanting, kissing lesions determined by MRI as Modified Outerbridge Grade IV patellar facet lesions in direct contact with Grade III or IV trochlea lesions or Grade III or IV femoral condyle lesions in direct contact with Grade IV tibial plateau lesions, bone edema at lesion location on MRI, active local infection, sepsis, osteomyelitis, tumor, advanced degenerative joint changes (joint space narrowing more than 50%), any known systemic cartilage and / or bone disorder, such as, but not limited to, osteoporosis, chondrodysplasia or osteogenesis imperfecta, requires bilateral knee surgery, Body Mass Index more than 40 (BMI=kg / m2), known insulin dependent diabetes mellitus, steroid treatment (oral or IV) within 6 months prior to the implanting. In some embodiments, the subject treated with the tissue implant may be between 22 and 60 years of age. In some embodiments, the implant can be implanted using an arthroscopic or a mini-open procedure. In some embodiments, the implanting may comprise preparing a cylindrical cavity at an implantation site and inserting the tissue implant into the cylindrical cavity. In some embodiments, a kit comprising a packaging containing therein a tissue implant may be provided. In some embodiments, the packaging can comprise the tissue implant submerged in water. In some embodiments, the tissue implant within the kit may not be sterile. In some embodiments, the packaging can be capable of being autoclaved. In some embodiments, the kit may further comprise instructions for implanting the tissue implant into a tissue.

[0014]

[0009] Additional aspects and advantages of the present disclosure will become readily apparent to those skilled in this art from the following detailed description, wherein only illustrative embodiments of the present disclosure are shown and described. As will be realized, the present disclosure is capable of other and different embodiments, and its several details are capable of WSGR Docket No. 52715-711.601 modifications in various obvious respects, all without departing from the disclosure. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive.

[0015] BRIEF DESCRIPTION OF THE DRAWINGS

[0016]

[0010] A better understanding of the features and advantages of the present subject matter will be obtained by reference to the following detailed description that sets forth illustrative embodiments and the accompanying drawings of which:

[0017] [Oil] FIGS. 1A-1C illustrate several embodiments of a tissue implant comprising tissue implant regions.

[0018]

[0012] FIG. 2 illustrates a cross section of a tissue implant comprising tissue implant regions including a press-fit ring configuration.

[0019]

[0013] FIG. 3 illustrates drilling a socket into a bone of a patient.

[0020]

[0014] FIGS. 4A and 4B illustrate a tool for insertion of a tissue implant into a tissue of a patient.

[0021]

[0015] FIG. 5 illustrates a tissue implant insertion tool configured to compress a tissue implant.

[0022]

[0016] FIGS. 6A and 6B illustrates the Post-Insertion Positioning of the Tissue Implant in the Patient's Bone.

[0023]

[0017] FIG. 7 illustrates an instrument set designed for surgical procedures.

[0024]

[0018] FIGS. 8A-8E illustrates the sequential use of the instrument set from FIG. 7 in a surgical procedure.

[0025] INCORPORATION BY REFERENCE

[0026]

[0019] All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference. To the extent publications and patents or patent applications incorporated by reference contradict the disclosure contained in the specification, the specification is intended to supersede and / or take precedence over any such contradictory material.

[0027] DETAILED DESCRIPTION

[0028]

[0020] While preferred embodiments of the present subject matter have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions may occur to those skilled in the art without departing from the present subject matter. It should be understood WSGR Docket No. 52715-711.601 that various alternatives to the embodiments of the present subject matter described herein may be employed in practicing the present subject matter.

[0029]

[0021] Whenever the term “at least,” “greater than,” or “greater than or equal to” precedes the first numerical value in a series of two or more numerical values, the term “at least,” “greater than” or “greater than or equal to” applies to each of the numerical values in that series of numerical values. For example, greater than or equal to 1, 2, or 3 is equivalent to greater than or equal to 1, greater than or equal to 2, or greater than or equal to 3.

[0030]

[0022] Whenever the term “no more than,” “less than,” or “less than or equal to” precedes the first numerical value in a series of two or more numerical values, the term “no more than,” “less than,” or “less than or equal to” applies to each of the numerical values in that series of numerical values. For example, less than or equal to 3, 2, or 1 is equivalent to less than or equal to 3, less than or equal to 2, or less than or equal to 1.

[0031]

[0023] Certain inventive embodiments herein contemplate numerical ranges. When ranges are present, the ranges include the range endpoints. Additionally, every sub range and value within the range is present as if explicitly written out. The term “about” or “approximately” may mean within an acceptable error range for the particular value, which will depend in part on how the value is measured or determined, e.g., the limitations of the measurement system. For example, “about” may mean within 1 or more than 1 standard deviation, per the practice in the art. Alternatively, “about” may mean a range of up to 20%, up to 10%, up to 5%, or up to 1% of a given value. Where particular values are described in the application and claims, unless otherwise stated the term “about” meaning within an acceptable error range for the particular value may be assumed.

[0032] Detailed Description

[0033]

[0024] The invention is a tissue implant made of a polymer material, intended for implantation into an articular surface of bone. The implant comprises multiple regions with different infill densities. The materials that can be used in the implant may include a variety of thermoplastic polymers, which can be either resorbable or non-resorbable. The design of the implant also includes a third region with a ring-like structure, which can be integrated into the implant to help secure it in place after implantation. The implant is designed to have an elastic modulus that is comparable to that of native cartilage and can withstand mechanical loading.

[0034]

[0025] In some embodiments, a tissue implant may comprise five regions. In some embodiments, the first region may comprise a top layer which can be more than 75% solid, with a reinforcing ring serving as a circumferential reinforcement. In some embodiments, the second region can comprise a lattice structure, a carryover of our previous design. In some WSGR Docket No. 52715-711.601 embodiments, the third region can include the first ring, which can be 0.4mm thick and printed as a series of concentric circles radially extending outward. In some embodiments, the fourth region may involve a hollow-lattice structure, with boundaries equal to the wall thickness of the ring. In some embodiments, the fifth region may incorporate the second ring, which can be a bottom-most region and has a beveled edge to minimize tissue disruption upon placement. In some embodiments, a tissue implant may comprise three regions. The first region may comprise numerous layers arranged in a lattice structure. The lattice structure refers to a pattern of layers or compartments, like a grid or a framework, which is repeated throughout the structure. This region can include a bottom layer, several middle layers, and a top layer, with all these layers having an infill density of at least about 20%. In some other embodiments, the second region can comprise at least one layer adjacent to the top layer of the first region, with an infill density of at least about 75%. In still other embodiments, a third region can comprise a ring-like structure situated along the outer circumference of the tissue implant. In some embodiments, the layers of each region can be stacked on top of each. This arrangement can be similar to a sandwich or a stack of papers, where each layer has a specific place, with each one residing on top of the previous layer. The phrase "at least about 20%" means that the infill density of the layers in the first region is no less than approximately 20%. Infill density refers to the amount of material in the interior of each layer. A higher infill density indicates more material and less empty space in each layer, resulting in a denser and potentially stronger layer. The phrase "at least about 75%" indicates that the infill density of the at least one layer in the second region is no less than approximately 75%. This suggests that the second region can be denser than the first region. The densities could possibly vary within a certain range depending on physical characteristics of the implant. For example, the infill density of the first region could potentially range about 20% to about 25%, about 25% to about 30%, about 30% to about 35%, about 35% to about 40%, about 40% to about 45%, about 45% to about 50%, about 50% to about 55%, about 55% to about 60%, about 60% to about 65%, about 65% to about 70%, about 70% to about 75%, and so on, up to about 95% to about 100%. The infill density of the second region could range bout 75% to about 80%, about 80% to about 85%, about 85% to about 90%, about 90% to about 95%, and about 95% to about 100%. These ranges allow for the customization of the implant properties as per specific requirements. In some embodiments, the infill density of the first region of the tissue implant may be from about 50% to about 65%. In some embodiments, the infill density of the first region can range from about 55% to about 60%. In some embodiments, the infill density of the first region may be about 58%. In some embodiments, the infill density of the second region can range from about 85% to about 100%. In some embodiments, the infill density of the second region can be about 90%. WSGR Docket No. 52715-711.601

[0035]

[0026] In some embodiments, each layer of the first region may have a thickness ranging from about 0.05 mm to about 0.10 mm, about 0.10 mm to about 0.15 mm, about 0.15 mm to about 0.20 mm, about 0.20 mm to about 0.25 mm, about 0.25 mm to about 0.30 mm, about 0.30 mm to about 0.35 mm, about 0.35 mm to about 0.40 mm, about 0.40 mm to about 0.45 mm, about 0.45 mm to about 0.50 mm, about 0.50 mm to about 0.55 mm, about 0.55 mm to about 0.60 mm, about 0.60 mm to about 0.65 mm, about 0.65 mm to about 0.70 mm, about 0.70 mm to about 0.75 mm, about 0.75 mm to about 0.80 mm, about 0.80 mm to about 0.85 mm, about 0.85 mm to about 0.90 mm, about 0.90 mm to about 0.95 mm, and about 0.95 mm to about 1 mm. In some embodiments, each layer of the first region can be about 0.2 mm in thickness. In some embodiments, the at least one layer of the second region can have a thickness ranging from about 0.1 mm to about 0.4 mm. In some embodiments, the single layer of the second region can be about 0.2 mm in thickness.

[0036]

[0027] In some embodiments, each layer of the plurality of layers of the first region may be composed of a polymer material. The polymer material can vary and may include a wide range of materials. Examples of these materials may include but are not limited to polyvinyl alcohol (PVA), Nylon, or polyamide, Polyether Ether Ketone (PEEK), Polylactic Acid (PLA), Poly caprolactone (PCL), Polylactic-co-glycolic acid (PLGA), Polyethylene Terephthalate Glycol (PETG), Polyglycolic Acid (PGA), Polyhydroxyalkanoates (PHAs), Polycarbonates, Polyamides, Polyurethanes, Poly (methyl methacrylate) (PMMA), and Polystyrene, Polyvinyl Chloride (PVC), Polypropylene (PP), Polyethylene (PE), Acrylonitrile Butadiene Styrene (ABS), Polyoxymethylene (POM), Polytetrafluoroethylene (PTFE), Poly etherimide (PEI), and Thermoplastic Polyurethane (TPU), among others. In some embodiments, the at least one layer of the second region can be composed of a polymer material. In some embodiments, the polymer material may comprise a thermoplastic polymer. In some embodiments, the thermoplastic polymer can comprise resorbable materials. The resorbable, or biodegradable, materials are designed to break down within the body over time, after they have served their purpose. This breakdown can happen through various biological processes, and the material's degradation products are typically excreted from the body naturally. Examples of such resorbable materials can include Polylactic Acid (PLA), Polycaprolactone (PCL), Polylactic-co-glycolic acid (PLGA), and Polyglycolic Acid (PGA), among others. In some embodiments, the thermoplastic polymer may comprise non-resorbable materials. The non-resorbable, or non-degradable, materials do not break down over time within the body and are intended to be permanent. These materials are typically used when long-term structural support is needed. Examples of non- resorbable materials can include Polyvinyl Alcohol (PVA), Nylon, Polyether Ether Ketone WSGR Docket No. 52715-711.601

[0037] (PEEK), Polyethylene Terephthalate Glycol (PETG), Polypropylene (PP), Polyethylene (PE), and Polyvinyl Chloride (PVC), among others.

[0038]

[0028] In some embodiments, the polymer material can comprise polyvinyl alcohol (PVA). In some embodiments, the polymer material may comprise a composite of nylon and PVA. In some embodiments, the polymer material can comprise greater than about 30% PVA. In some embodiments, the polymer material can comprise of about 30% to about 35%, about 35% to about 40%, about 40% to about 45%, about 45% to about 50%, about 50% to about 55%, about 55% to about 60%, about 60% to about 65%, about 65% to about 70%, about 70% to about 75%, about 75% to about 80%, about 80% to about 85%, about 85% to about 90%, about 90% to about 95%, and about 95% to about 100% PVA. In some cases, the polymer material can comprise less than about 30% PVA, for example, less than about 25% PVA, less than about 20% PVA, less than aobut 15% PVA%, less than about 10% PVA, less than about 5% PVA, less than about 4% PVA, less than about 3% PVA, less than about 2% PVA, less than about 1% PVA, or about 0% PVA. In some cases, the polymer material comprises more than about 70% nylon, more than about 75% nylon, more than about 80% nylon, more than about 85% nylon, more than about 90% nylon, more than about 95% nylon, more than about 96% nylon, more than about 97% nylon, more than about 98% nylon, more than about 99% nylon, or about 100% nylon. In some embodiments, each layer of the plurality of the layers of the first region may be arranged in a discontinuous unidirectional or continuous serpentine configuration. A discontinuous unidirectional configuration may refer to a pattern where each layer is oriented in the same direction (unidirectional), but there are gaps or breaks within the layer. On the other hand, a continuous serpentine configuration may refer to a pattern where each layer follows a curving, winding path without any breaks or gaps. In some embodiments, each layer of the plurality of the layers of the first region can be at a rotational offset relative to an adjacent layer. In some embodiments, the rotational offset can be from about 5 to about 175 degrees. In some embodiments, the rotational offset can be from about 5 degrees to about 10 degrees, about 10 degrees to about 15 degrees, about 15 degrees to about 20 degrees, about 20 degrees to about 25 degrees, about 25 degrees to about 30 degrees, about 30 degrees to about 35 degrees, about 35 degrees to about 40 degrees, about 40 degrees to about 45 degrees, about 45 degrees to about 50 degrees, about 50 degrees to about 55 degrees, about 55 degrees to about 60 degrees, about 60 degrees to about 65 degrees, about 65 degrees to about 70 degrees, about 70 degrees to about 75 degrees, about 75 degrees to about 80 degrees, about 80 degrees to about 85 degrees, about 85 degrees to about 90 degrees, about 90 degrees to about 95 degrees, about 95 degrees to about 100 degrees, about 100 degrees to about 105 degrees, about 105 degrees to about 110 degrees, about 110 degrees to about 115 degrees, about 115 degrees to about 120 degrees, about 120 WSGR Docket No. 52715-711.601 degrees to about 125 degrees, about 125 degrees to about 130 degrees, about 130 degrees to about 135 degrees, about 135 degrees to about 140 degrees, about 140 degrees to about 145 degrees, about 145 degrees to about 150 degrees, about 150 degrees to about 155 degrees, about 155 degrees to about 160 degrees, about 160 degrees to about 165 degrees, and about 165 degrees to about 170 degrees, about 170 degrees to about 175 degrees.

[0039]

[0029] In some embodiments, the at least one layer of the second region may comprise a reinforcing circumferential ring outlining a perimeter of the second region. In some embodiments, the at least one layer of the second region can be arranged in a linear, a serpentine, or a radial configuration. In some embodiments, the tissue implant can be sized and shaped for implantation into an articular surface of bone. As depicted in FIGS. 1A-1C, the tissue implant may comprise a region of press fit rings 101 which can be a rigid region of the implant designed to achieve press fit fixation when implanted into a prepared socket in the patient’s tissue or bone, a region of porous lattice 102 which can be a porous region of the implant designed to fill and support a cartilage lesion while facilitating the engraftment of the repair tissue to the underlying bone, and a region of top layer 103 which can be a non-porous top layer designed to help encapsulate cells. A shape may comprise a cylinder, sphere, rectangular prism, hollow tube, toroid, or combinations thereof. In some embodiments, the tissue implant may be cylindrical in shape. FIG. 2 illustrated a cross-sectional view of the tissue implant. As shown in FIG. 2, the tissue implant may comprise three regions including a region of press fit rings 201, a region of porous lattice 202, a region of top layer 203. In some embodiments, the design of the tissue implant may include an empty space 204. This space facilitates contact between the inner surface of the tissue implant and the patient's tissue or bone. The direct interaction between the implant and the patient's own tissues can enhance integration of the implant and promote healing and tissue regeneration in the area.

[0040]

[0030] In some embodiments, the implant can be at least about 10 mm in diameter. In some embodiments, the implant may be from about 10 mm to about 20 mm in diameter. In some embodiments, the implant may be from about 10 mm to about 11 mm, about 11 mm to about 12 mm, about 12 mm to about 13 mm, about 13 mm to about 14 mm, about 14 mm to about 15 mm, about 15 mm to about 16 mm, about 16 mm to about 17 mm, about 17 mm to about 18 mm, about 18 mm to about 19 mm, and about 19 mm to about 20 mm. In some embodiments, the tissue implant can be from about 2 mm to about 10 mm in thickness. In some embodiments, the tissue implant can be from about 2 mm to about 3 mm, about 3 mm to about 4 mm, about 4 mm to about 5 mm, and about 5 mm to about 6 mm, about 6 mm to about 7 mm, about 7 mm to about 8 mm, about 9 mm to about 10 mm. In some embodiments, the tissue implant may be about 4 mm in thickness. WSGR Docket No. 52715-711.601

[0041]

[0031] In some embodiments, the tissue implant may have a compressibility of at least about 200 1 / kPa. In some embodiments, the tissue implant may have a compressibility of about 200 1 / kPa to about 300 1 / kPa, about 300 1 / kPa to about 400 1 / kPa, about 400 1 / kPa to about 500 1 / kPa, about 500 1 / kPa to about 600 1 / kPa, about 600 1 / kPa to about 700 1 / kPa, about 700 1 / kPa to about 800 1 / kPa, about 800 1 / kPa to about 900 1 / kPa, about 900 1 / kPa to about 1000 1 / kPa, about 1000 1 / kPa to about 1100 1 / kPa, about 1100 1 / kPa to about 1200 1 / kPa, about 1200 1 / kPa to about 1300 1 / kPa, about 1300 1 / kPa to about 1400 1 / kPa, about 1400 1 / kPa to about 1500 1 / kPa, about 1500 1 / kPa to about 1600 1 / kPa, about 1600 1 / kPa to about 1700 1 / kPa, about 1700 1 / kPa to about 1800 1 / kPa, about 1800 1 / kPa to about 1900 1 / kPa, and about 1900 1 / kPa to about 2000 1 / kPa. In some embodiments, the first region can have a porosity of at least about 58%. In some embodiments, the first region can have a porosity of at least about 58% to about 63%, about 63% to about 68%, about 68% to about 73%, about 73% to about 78%, about 78% to about 83%, about 83% to about 88%, about 88% to about 93%, about 93% to about 98% and about 98% to about 100%.

[0042]

[0032] In some embodiments, the bottom layer and a periphery of the first region may comprise a porosity configured to engraftment of the tissue implant into the tissue. In some embodiments, the bottom layer and at least an adjacent layer of the plurality of middle layers can be non- continuous layers defining a cylindrical pocket disposed within the first region. In some embodiments, the cylindrical pocket may be configured to accept a bone post in the tissue. In some embodiments, the tissue implant can further comprise a third region having a ring-like structure and disposed along the outer circumference of the tissue implant. In some embodiments, the third region may have an infill density of about 100%. In some embodiments, the third region can be composed of a polymer material. In some embodiments, the third region may be composed of the same polymer material as the first region and the second region. In some embodiments, the polymer material can be a composite of nylon 12 and PVA.

[0043]

[0033] In some embodiments, the third region of the tissue implant may be integrated with the tissue implant. In some embodiments, the third region can be at least about 0.5 mm in thickness. In some embodiments, the third region may be about 1 mm in thickness. In some embodiments, the third region can comprise a press-fit ring configured to hold the implant in a tissue cavity. In some embodiments, the third region may comprise two press-fit rings. In some embodiments, a separation distance of two press-fit rings can be from about 0.05mm to about 5mm. In some embodiments, the separation distance can be about 0.05mm to about 0.10mm, about 0.10mm to about 0.15mm, about 0.15mm to about 0.20mm, about 0.20mm to about 0.25mm, about 0.25mm to about 0.30mm, about 0.30mm to about 0.35mm, about 0.35mm to about 0.40mm, about 0.40mm to about 0.45mm, about 0.45mm to about 0.50mm... continue this pattern to about WSGR Docket No. 52715-711.601

[0044] 4.95mm to about 5mm. In some embodiments, the two press-fit rings may be separated by a distance of at least 0.05mm. In some embodiments, the two press-fit rings may be separated by a distance of at least 0.4mm. In some embodiments, the third region can comprise a press-fit ring disposed at or near the bottom layer of the first region of the tissue implant. In some embodiments, the press-fit ring disposed at or near the bottom layer of the first region of the tissue implant may have a beveled edge. In some embodiments, the tissue implant can be configured to be compressed to fit into a tissue cavity, and to expand after implantation such that the press-fit ring engages with a surface of the tissue cavity and holds the tissue implant in place. In some embodiments, the third region can be at least about 1 mm larger in diameter than a diameter of the tissue cavity. In some embodiments, the third region of the tissue implant may have a higher rigidity than the first region. In some embodiments, the first region of the tissue implant can have an elastic modulus comparable to native cartilage.

[0045] 1034] In some embodiments, an elastic modulus of the first region can be from about 200 kPa to about 0.5 GPa. In some embodiments, the elastic modulus can be about 200 kPa to about 400 kPa, about 400 kPa to about 600 kPa, about 600 kPa to about 800 kPa, about 800 kPa to about 1 MPa, about 1 MPa to about 100 MPa, about 100 MPa to about 200 MPa, about 200 MPa to about 300 MPa, about 300 MPa to about 400 MPa, and finally about 400 MPa to about 500 MPa. In some embodiments, the first region of the tissue implant may have an elastic modulus of about 200 IkPa. In some embodiments, an elastic modulus of the third region can be from about 200 kPa to about 4 GPa. In some embodiments, the elastic modulus can be about 200 kPa to about 400 kPa, about 400 kPa to about 600 kPa, about 600 kPa to about 800 kPa, about 800 kPa to about 1 MPa, about 1 MPa to about 100 MPa, about 100 MPa to about 200 MPa, about 200 MPa to about 300 MPa, about 300 MPa to about 400 MPa, about 400 MPa to about 500 MPa, about 500 MPa to about 1 GPa, about 1 GPa to about 2 GPa, about 2 GPa to about 3 GPa, and finally about 3 GPa to about 4 GPa. In some embodiments, the third region of the tissue implant can have an elastic modulus of greater than about 200 IkPa. In some embodiments, the tissue implant may be configured to be implanted into a tissue by arthroscopic implantation or by a mini-open procedure. In some embodiments, the tissue implant can be an osteochondral implant. In some embodiments, the tissue implant may be configured to withstand mechanical loading of 334N for 20,000 cycles. In some embodiments, the average pull-out force of the tissue implant, when implanted into a tissue cavity, can be greater than 20 N. In some embodiments, the tissue implant may be configured to be implanted into the articular surface of the trochlea. In some embodiments, the tissue implant can be configured to be implanted into the articular surface of the medial condyle. In some embodiments, the tissue implant may be configured to be implanted into the articular surface of the lateral condyle. WSGR Docket No. 52715-711.601

[0046]

[0035] In some embodiments, the tissue implant may have a shelf-life of at least 12 months when stored in water at a room temperature. In some embodiments, a room temperature range can be from about 15degC to about 35degC. In some embodiments, the room temperature range can be about 15degC to about 20degC, about 20degC to about 25degC, about 25degC to about 30degC, and finally about 30degC to about 35degC.

[0047]

[0036] FIG. 3 illustrates drilling a socket into a bone of a patient. A guide pin 301 may be drilled into a tissue of a patient 302. The tissue can comprise cartilage, bone, or a combination thereof. A tissue may comprise a femur, tibia, patella, acetabulum, or other bones. A reamer 303 may then drill a socket 304 into the tissue. The reamer may be guided by the guide pin. In some embodiments, a punch can be used to prepare the implantation site. This step involves sliding the punch over the Guide Pin to score the implantation site tissue, thereby separating it from the adjacent cartilage prior to reaming. In some embodiments, the reamer may comprise teeth at a plurality of cutting depths. The reamer may comprise teeth at 1, 2, 3, 4, or more cutting depths. The reamer may comprise 1, 2, 3, 4, or more cutting teeth. In some embodiments, the reamer has 4 cutting teeth: two outer teeth, and two inner teeth. The outer teeth may prepare an annular (ring shaped) socket at a first depth. The inner teeth may prepare a flat inner region at a second depth. The first depth may be deeper that the second depth. In some embodiments the reamer comprises a depth stop. The depth stop may correspond to the tissue implant. The socket may be shaped to receive the tissue implant. The tissue implant and socket may comprise matching geometries.

[0048]

[0037] FIG. 4A and FIG. 4B illustrates an example tool 400 for insertion of a tissue implant into a tissue of a patient. The insertion tool may comprise a cylindrical shaft 401 comprising: an inner pushing portion 402; a hollow distal end comprising a pocket 403 wherein the pushing portion 402 contacts the pocket; and a button 404 mechanically connected to the hollow distal end. The pocket may be configured to receive a tissue implant 405. In some embodiments, the pocket can be cylindrical. The pocket can be about 1, 2, 3, 4, 5 or 6 mm deep. The pocket can be at most as deep as the length of a tissue implant. The pocket may hold the top half of a tissue implant. The tissue implant may comprise an attachment element in a press-fit ring configuration. The pushing portion may contact the tissue implant when inserted into the pocket. In some embodiments, the hollow distal end may comprise a tube 406. The tube may comprise 1, 2, 3, 4, or more relief flutes 407. The tube may flex and receive the implant while applying a clamping force to hold the implant. In some embodiments, pushing the button retracts the tube. The retraction of the tube may cause the tissue implant to be pushed out of the hollow distal end by the pushing portion. A surgeon can place the implant into a socket, press the button to retract the tube, and then place the implant all the way in. In some embodiments, the surgeon may place WSGR Docket No. 52715-711.601 the implant halfway into the socket, or about 2mm into the socket. In some embodiments, the surgeon may place the implant with one hand while holding an arthroscopic camera (or other instrument) with their other hand.

[0049]

[0038] FIG. 5 illustrates an example of the tissue implant insertion tool 500 configured to compress a tissue implant 501. In some embodiments, the insertion tool comprises tips or tines 502 that are optimized for the shape of a tissue implant. In some embodiments, the tissue implant insertion tool comprises: a first lever portion 503 comprising a first distal end 504, a first middle portion 505, and a first proximal end 506, wherein the first distal end comprises a first compression tine 507; and a second lever portion 508 comprising a second distal end 509, a second middle portion 510, and a second proximal end 511, wherein the second distal end comprises a second compression tine 512; wherein the first lever portion 503 and second lever portion 508 are pivotally coupled at the first middle portion 504 and the second middle portion 510, wherein the first compression tine 507 and the second compression tine 512 are configured to engage a portion of a tissue implant 501. In some embodiments, the tissue implant is compressible.

[0050]

[0039] In some embodiments, FIG. 6A and FIG. 6B may provide visual representations of the tissue implant 601, after it has been inserted into a patient's bone 602. The figures can potentially show the tissue implant's position relative to the surrounding bone and how it is seated within the prepared socket. The figures may illustrate the top region of the tissue implant inside the cylindrical pocket. The figures may illustrate an integration of the implant with the surrounding bone tissue and some example design features of the implant, such as its shape, size, and porosity.

[0051]

[0040] FIG. 7 illustrates an example of an instrument set used for surgical procedures. In some embodiments, the instrument set comprises a Sizing / Alignment Guide 701. This tool can assist in determining the appropriate dimensions for an implant and ensuring the correct positioning during the procedure. In some embodiments, the instrument set also includes a Guide Pin 702. This tool can be used to assist with aligning the surgical instruments and establishing a pathway for the procedure. The instrument set also features a Punch 703 in some embodiments. This tool may be used for creating an opening in the tissue or bone to facilitate implant insertion. In certain embodiments, the instrument set comprises a Reamer 704. This tool can be utilized to smooth or enlarge the created opening to fit the implant accurately. In some embodiments, a Depth Stop 705 is also included in the instrument set. This component is employed to limit the depth of penetration of other instruments to ensure accurate positioning and prevent damage to surrounding structures. Lastly, in some embodiments, the instrument set includes an Insertion WSGR Docket No. 52715-711.601

[0052] Tube 706. This tool is used to guide the implant into the prepared opening in a controlled and precise manner.

[0053]

[0041] FIGS. 8A-8E depict the steps involved in using the instrument set from FIG. 7 for surgical procedures. In FIG. 8A, in some embodiments, the Sizing / Alignment Guide 801 is first used to determine the appropriate dimensions for the implant and to confirm its proper positioning. Following this, in FIG. 8B, in some embodiments, the Guide Pin 802 is inserted to establish a pathway for the upcoming procedure. Then, in FIG. 8C, in some embodiments, the Punch 803 is applied to create an opening in the tissue or bone where the implant will be placed. Next, in FIG. 8D, in some embodiments, the Reamer 804 is used to smooth or widen the opening to ensure the implant fits accurately. Simultaneously, the Depth Stop 805, in some embodiments, is implemented to control the depth of penetration and to safeguard surrounding structures from potential damage. Finally, in FIG. 8E, in some embodiments, the Insertion Tube 806 is used to guide and insert the implant into the opening in a precise and controlled manner. This concludes the steps of using the instrument set in the depicted surgical procedure.

[0054] Examples

[0055]

[0042] In some embodiments, the tissue implant may be used in a method of treating a tissue defect in a subject, as an example. The method can involve implanting the tissue implant into the tissue defect, thereby treating the tissue defect in the subject. In some embodiments, the tissue defect treated by this method may be a critical-sized tissue defect. In some embodiments, the tissue defect treated can be an osteochondral defect or a chondral defect. In some embodiments, the method may be applied if the subject has damaged knee articular cartilage with osteoarthritis graded as Kellgren-Lawrence 0-3. In some embodiments, the subjects treated with the tissue implant can have medial or lateral femoral condyle and / or trochlea articular cartilage lesions of about 4 cm2 or less. In some embodiments, the subjects treated with the tissue implant may have a Visual Analog Scale (VAS) score of greater than or equal to 30 mm pain and less than or equal to 100 mm at baseline. In some embodiments, the tissue defect treated by the tissue implant can have an International Cartilage Repair Society (ICRS) of less than or equal to Grade 3C.

[0056]

[0043] In some embodiments, the subject treated with the tissue implant may not have one of the following conditions or treatments: rheumatoid arthritis, inflammatory joint disease, avascular necrosis, osteoarthritis Grade 4 according to Kellgren-Lawrence grading, flexion contracture of more than 10 degrees, more than 8 degrees of physiologic vagus or varus based on leg length (hip to ankle) AP weight bearing x-ray, prior arthroscopy within 3 months prior to the implanting for joint lavage, chondral debridement, and / or loose body removal, meniscal transplantation within 6 months prior to the implanting, ligamentous repair or malalignment correction within 6 months prior to the implanting, treated for cartilage repair prior to the WSGR Docket No. 52715-711.601 implanting, intra-articular steroid therapy or intra-articular hyaluronic acid therapy within 6 months prior to the implanting, kissing lesions determined by MRI as Modified Outerbridge Grade IV patellar facet lesions in direct contact with Grade III or IV trochlea lesions or Grade III or IV femoral condyle lesions in direct contact with Grade IV tibial plateau lesions, bone edema at lesion location on MRI, active local infection, sepsis, osteomyelitis, tumor, advanced degenerative joint changes (joint space narrowing more than 50%), any known systemic cartilage and / or bone disorder, such as, but not limited to, osteoporosis, chondrodysplasia or osteogenesis imperfecta, requires bilateral knee surgery, Body Mass Index more than 40 (BMI=kg / m2), known insulin dependent diabetes mellitus, steroid treatment (oral or IV) within 6 months prior to the implanting.

[0057]

[0044] In some embodiments, the subject treated with the tissue implant may be between 22 and 60 years of age. In some embodiments, the implant can be implanted using an arthroscopic or a mini-open procedure. In some embodiments, the implanting may comprise preparing a cylindrical cavity at an implantation site and inserting the tissue implant into the cylindrical cavity. In some embodiments, a kit comprising a packaging containing therein a tissue implant may be provided. In some embodiments, the packaging can comprise the tissue implant submerged in water. In some embodiments, the tissue implant within the kit may not be sterile. In some embodiments, the packaging can be capable of being autoclaved. In some embodiments, the kit may further comprise instructions for implanting the tissue implant into a tissue.

[0058]

[0045] As another example, a patient is selected for surgery based on specific criteria related to the type, location, and extent of the cartilage damage, as well as the patient's overall health status and suitability for the procedure. The selected patient may, for instance, have a damaged knee articular cartilage with osteoarthritis graded as Kellgren-Lawrence 0-3, and a VAS pain score greater than or equal to 30 mm but less than or equal to 100 mm. The lesion might be about 4 cm2 or less in size. The surgical procedure begins with a standard diagnostic knee arthroscopy or mini arthrotomy procedure. The chondral lesion in the patient's knee is then measured with a Sizing / Alignment Guide to determine the appropriate size of the tissue implant needed. Following this, a Guide Pin is placed into the Sizing / Alignment Guide to establish the orientation of the implant. The Guide Pin is drilled into the bone until the depth stop line reaches the alignment guide. In some embodiments, the depth stop can be in a size of 10, 15, or 20. If desired, the surgeon can choose to use an optional punch supplied with the instrument set to prepare the implantation site. This step involves sliding the punch over the Guide Pin to score the implantation site tissue, thereby separating it from the adjacent cartilage prior to reaming. The appropriately sized reamer is used to drill or prepare a cylindrical socket in the bone to receive the tissue implant. This socket is designed such that the 4 mm thick tissue implant sits WSGR Docket No. 52715-711.601 flush or slightly recessed in the prepared socket. Once the socket is ready, an insertion tool or tube is used to place the tissue implant into the prepared defect. The tissue implant is then press- fit into the defect. Device fixation is achieved via two integrated press-fit rings. Once properly seated, all edges of the implant should be flush or recessed at the cartilage, ensuring a smooth transition between the implant and the surrounding natural tissue.

[0059]

[0046] To carry out the surgical procedure mentioned in the example, several types of surgical instruments and equipment are required. The process would first call for standard instruments needed for either a knee arthroscopy or a mini arthrotomy procedure. These could include an arthroscope, which is a type of endoscope inserted into the joint through a small incision, a trocar for creating the pathway to the joint, and a cannula which serves as a portal through which the arthroscope and other instruments are inserted. Next, a Sizing / Alignment Guide is used, which serves two essential functions. Firstly, it is used to measure the chondral lesion, providing the surgeon with the necessary information to choose an appropriately sized implant. Secondly, it aids in establishing the orientation of the implant, ensuring its correct positioning. In some embodiments, the alignment guide can be in a size of 10, 12.5, 15, 17.5 or 20. A Guide Pin is another crucial tool used in this surgery. The Guide Pin is placed into the Sizing / Alignment Guide and then drilled into the bone. This pin acts as a guide, helping the surgeon maintain the correct alignment while preparing the implant site. An optional tool is the punch, which can be used when the surgeon decides to separate the implantation site cartilage from the adjacent cartilage prior to reaming. The punch, slid over the Guide Pin, scores the implantation site tissue creating a small grove or depression. In some embodiments, the punch can be in a size of 10, 15, or 20. The reamer, which is selected based on the size determined by the Sizing / Alignment Guide, is used to prepare a cylindrical socket in the bone to receive the tissue implant. In some embodiments, the reamer can be in a size of 10, 15, or 20. This socket is designed such that the implant fits snugly and is either flush or slightly recessed compared to the surrounding bone. Finally, an insertion tool or tube is used to place the tissue implant into the prepared defect. In some embodiments, the insertion tube can be in a size of 10, 15, or 20. The tissue implant is loaded into the tube, which is then used to guide the implant into the exact position within the prepared socket. After this step, the implant is then press-fit into the defect. The press-fit rings on the implant help to achieve the fixation of the device. As part of the process, a variety of other standard surgical tools may also be used, including surgical drapes, sutures, forceps, surgical gloves, antiseptic solutions, and dressings. Moreover, an imaging system such as an arthroscopic camera system may also be required to visualize the surgical area during the procedure.

Claims

WSGR Docket No. 52715-711.601CLAIMSWHAT IS CLAIMED IS:

1. A tissue implant comprising:(a) a first region comprising a plurality of layers arranged in a lattice structure, the plurality of layers comprising a bottom layer, a plurality of middle layers, and a top layer, wherein the plurality of layers has an infill density of at least about 20%; and(b) a second region having at least one layer with an infill density of at least about 75%, adjacent to the top layer of the first region.

2. The tissue implant of claim 1, wherein the infill density of the first region is from about 50% to about 65%.

3. The tissue implant of claim 1 or 2, wherein the infill density of the first region is from about 55% to about 60%.

4. The tissue implant of any one of claims 1-3, wherein the infill density of the first region is about 58%.

5. The tissue implant of any one of claims 1-4, wherein the infill density of the second region is from about 85% to about 100%.

6. The tissue implant of any one of claims 1-5, wherein the infill density of the second region is about 90%.

7. The tissue implant of any one of claims 1-6, wherein each layer of the first region is from about 0.05 mm to about 1mm in thickness.

8. The tissue implant of any one of claims 1-7, wherein each layer of the first region is about 0.2 mm in thickness.

9. The tissue implant of any one of claims 1-8, wherein the at least one layer of the second region is from about 0.1 mm to about 0.4 mm in thickness.

10. The tissue implant of claim 1, wherein the single layer of the second region is about 0.2 mm in thickness.

11. The tissue implant of any one of claims 1-10, wherein each layer of the plurality of layers of the first region are composed of a polymer material.WSGR Docket No. 52715-711.60112. The tissue implant of any one of claims 1-11, wherein the at least one layer of the second region is composed of a polymer material.

13. The tissue implant of claim 11 or 12, wherein the polymer material comprises a thermoplastic polymer.

14. The tissue implant of claim 13, wherein the thermoplastic polymer comprises resorbable materials.

15. The tissue implant of claim 14, wherein the thermoplastic polymer comprises non- resorbable materials.

16. The tissue implant of any one of claims 11-15, wherein the polymer material comprises polyvinyl alcohol (PVA).

17. The tissue implant of any one of claims 1-16, wherein the polymer material comprises a composite of nylon and PVA.

18. The tissue implant of claim 17, wherein the polymer material comprises greater than about 30% PVA.

19. The tissue implant of any one of claims 1-18, wherein each layer of the plurality of the layers of the first region is arranged in a discontinuous unidirectional or continuous serpentine configuration.

20. The tissue implant of any one of claims 1-19, wherein each layer of the plurality of the layers of the first region is at a rotational offset relative to an adjacent layer.

21. The tissue implant of claim 20, wherein the rotational offset is from about 5 to about 175 degrees.

22. The tissue implant of any one of claims 1-21, wherein the at least one layer of the second region comprises a reinforcing circumferential ring outlining a perimeter of the second region.

23. The tissue implant of any one of claims 1-22, wherein at least one layer of the second region is arranged in a linear, a serpentine, or a radial configuration.

24. The tissue implant of any one of claims 1-23, wherein the tissue implant is sized and shaped for implantation into an articular surface of bone.WSGR Docket No. 52715-711.60125. The tissue implant of any one of claims 1-24, wherein the tissue implant is cylindrical in shape.

26. The tissue implant of any one of claims 1-25, wherein the implant is at least about 10 mm in diameter.

27. The tissue implant of any one of claims 1-26, wherein the implant is from about 10 mm to about 20 mm in diameter.

28. The tissue implant of any one of claims 1-27, wherein the tissue implant is from about 2 mm to about 10 mm in thickness.

29. The tissue implant of any one of claims 1-28, wherein the tissue implant is about 4 mm in thickness.

30. The tissue implant of any one of claims 1-29, wherein the tissue implant has a compressibility of at least about 200 1 / kPa.

31. The tissue implant of any one of claims 1-30, wherein the first region has a porosity of at least about 58%.

32. The tissue implant of any one of claims 1-31, wherein the bottom layer and a periphery of the first region comprise a porosity configured to engraftment of the tissue implant into the tissue.

33. The tissue implant of any one of claims 1-32, wherein the bottom layer and at least an adjacent layer of the plurality of middle layers are non-continuous layers defining a cylindrical pocket disposed within the first region.

34. The tissue implant of claim 33, wherein cylindrical pocket is configured to accept a bone post in the tissue.

35. The tissue implant of any one of claims 1-34, further comprising a third region having a ring-like structure and disposed along the outer circumference of the tissue implant.

36. The tissue implant of claim 35, wherein the third region has an infill density of about 100%.

37. The tissue implant of claim 35 or 36, wherein the third region is composed of a polymer material.WSGR Docket No. 52715-711.60138. The tissue implant of claim 37, wherein the third region is composed of the same polymer material as the first region and the second region.

39. The tissue implant of claim 37 or 38, wherein the polymer material is a composite of nylon 12 and PVA.

40. The tissue implant of any one of claims 35-39, wherein the third region is integrated with the tissue implant.

41. The tissue implant of any one of claims 35-40, wherein the third region is at least about 0.5 mm in thickness.

42. The tissue implant of any one of claims 35-41, wherein the third region is about 1 mm in thickness.

43. The tissue implant of any one of claims 35-42, wherein the third region comprises a press-fit ring configured to hold the implant in a tissue cavity.

44. The tissue implant of claim 43, wherein the third region comprises two press-fit rings.

45. The tissue implant of claim 44, wherein the two press-fit rings are separated by a distance of at least 0.05mm.

46. The tissue implant of claim 44 or 45, wherein one of the two press-fit rings is disposed at or near the bottom layer of the first region of the tissue implant.

47. The tissue implant of claim 46, wherein the press-fit ring disposed at or near the bottom layer of the first region of the tissue implant has a beveled edge.

48. The tissue implant of any one of claims 1-47, wherein the tissue implant is configured to be compressed to fit into a tissue cavity, and to expand after implantation such that the press-fit ring engages with a surface of the tissue cavity and holds the tissue implant in place.

49. The tissue implant of claim 48, wherein the third region is at least about 1 mm larger in diameter than a diameter of the tissue cavity.

50. The tissue implant of any one of claims 35-49, wherein the third region has a higher rigidity than the first region.WSGR Docket No. 52715-711.60151. The tissue implant of any one of claims 1-50, wherein the first region has an elastic modulus comparable to native cartilage.

52. The tissue implant of any one of claims 1-51, wherein the first region has an elastic modulus of about 200 kPa to about 0.5GPa.

53. The tissue implant of any one of claims 35-52, wherein the third region has an elastic modulus of about 200 kPa to about 4GPa.

54. The tissue implant of any one of claims 1-53, wherein the tissue implant is configured to be implanted into a tissue by arthroscopic implantation or by a mini-open procedure.

55. The tissue implant of any one of claims 1-54, wherein the tissue implant is an osteochondral implant.

56. The tissue implant of any one of claims 1-55, wherein the tissue implant is configured to withstand mechanical loading of 334N for 20,000 cycles.

57. The tissue implant of any one of claims 1-56, wherein the average pull-out force of the tissue implant, when implanted into a tissue cavity, is greater than 20 N.

58. The tissue implant of any one of claims 1-57, wherein the tissue implant is configured to be implanted into the articular surface of the trochlea.

59. The tissue implant of any one of claims 1-58, wherein the tissue implant is configured to be implanted into the articular surface of the medial condyle.

60. The tissue implant of any one of claims 1-59, wherein the tissue implant is configured to be implanted into the articular surface of the lateral condyle.

61. The tissue implant of any one of claims 1-60, wherein the tissue implant has a shelf-life of at least 12 months when stored in water at a room temperature.

62. A method of treating a tissue defect in a subject, the method comprising: implanting a tissue implant of any one of claims 1-61 into the tissue defect, thereby treating the tissue defect in the subject.

63. The method of claim 62, wherein the tissue defect is a critical-sized tissue defect.WSGR Docket No. 52715-711.60164. The method of claim 62 or 63, wherein the tissue defect is an osteochondral defect or a chondral defect.

65. The method of any one of claims 62-64, wherein the subject has damaged knee articular cartilage with osteoarthritis graded as Kellgren-Lawrence 0-3.

66. The method of any one of claims 62-65, wherein the subject has medial or lateral femoral condyle and / or trochlea articular cartilage lesions of about 4 cm2or less.

67. The method of any one of claims 62-66, wherein the subject has a VAS score of greater than or equal to 30 mm pain and less than or equal to 100 mm at baseline.

68. The method of any one of claims 62-67, wherein the tissue defect has an ICRS of less than or equal to Grade 3C.

69. The method of any one of claims 62-68, wherein the subject does not have one of the following: rheumatoid arthritis, inflammatory joint disease, avascular necrosis, osteoarthritis Grade 4 according to Kellgren-Lawrence grading, flexion contracture of >10 degrees, >8 degrees of physiologic vagus or varus based on leg length (hip to ankle) AP weight bearing x-ray, prior arthroscopy within 3 months prior to the implanting for joint lavage, chondral debridement, and / or loose body removal, meniscal transplantation within 6 months prior to the implanting, ligamentous repair or malalignment correction within 6 months prior to the implanting, bone edema at lesion location on MRI, active local infection, sepsis, osteomyelitis, tumor, advanced degenerative joint changes (joint space narrowing >50%), any known systemic cartilage and / or bone disorder, such as, but not limited to, osteoporosis, chondrodysplasia or osteogenesis imperfecta, requires bilateral knee surgery, Body Mass Index >40 (BMI=kg / m2), known insulin dependent diabetes mellitus, steroid treatment (oral or IV) within 6 months prior to the implanting.

70. The method of any one of claims 62-69, wherein the subject is between 22 and 60 years of age.

71. The method of any one of claims 62-70, wherein the implant is implanted using an arthroscopic or a mini-open procedure.

72. The method of any one of claims 62-71, wherein the implanting comprises preparing a cylindrical cavity at an implantation site and inserting the tissue implant into the cylindrical cavity.WSGR Docket No. 52715-711.60173. A kit comprising a packaging containing therein a tissue implant of any one of claims 1- 61.

74. The kit of claim 73, wherein the packaging comprises the tissue implant submerged in water.

75. The kit of claim 73 or 74, wherein the tissue implant is not sterile.

76. The kit of any one of claims 73-75, wherein the packaging is capable of being autoclaved.

77. The kit of any one of claims 73-76, further comprising instructions for implanting the tissue implant into a tissue.

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