Patent Description:
The present description relates to the field of implants, and in particular to implants for insertion into a patient, and a method for forming an implant.

The insertion of implants into patients is performed in surgeries worldwide. Depending on the required use of the implant, an implant may be required to meet certain criteria. Such criteria may relate to the geometry of the implant and/or the mechanical stability of the implant. In some instances, such as wherein an implant may be used in reconstructive surgery, the implant may have to be handled by a surgeon before, during and/or after the implant is inserted into a patient. It is desirable to have an implant which meets the geometrical and mechanical criteria required by the patient, and which is easily handled and/or manipulated by surgeons performing implant surgery.

European application no. <CIT> discloses an implant for tissue reconstruction which comprises a scaffold structure that includes a void system for the generation of prevascularized connective tissue with void spaces for cell and/or tissue transplantation and a method of manufacturing such an implant, to the internal architecture of such an implant, to a removal tool for mechanical removal of space-occupying structures from such an implant, to a kit comprising such an implant and such a removal tool, to a removal device for the removal of superparamagnetic or fenomagnetic space-occupying structures from such an implant.

US patent application no. <CIT> discloses a three-dimensional tissue engineering scaffold device and related methods are disclosed herein. The tissue engineering scaffold includes a plurality of polymers sheets. Each polymer sheet includes a plurality of micro-scale pores defined through the polymer sheet. The polymer sheets of the tissue engineering scaffold are aligned and stacked such that some of the pores of neighboring sheets are offset along at least one axis of the pores. The offset pores create features within the tissue engineering scaffold.

Various embodiments relate to providing an implant which may be flexibly tailored to meet criteria required of a reconstruction to a patient's body part, and which also enhances and improves the handleability and manipulability of the implant by surgeons performing surgery.

The implant may be used for guiding a needle through the implant for implant surgery.

Various embodiments relate to a three-dimensional implant for tissue reconstruction or tissue augmentation for insertion into a patient. The implant comprises a plurality of planar layers. A first group of sublayers comprises a plurality of strands oriented in first direction. A second group of sublayers comprises a plurality of strands oriented in a second direction. The sublayers of the first group of sublayers and the sublayers of the second group of sublayers are arranged alternatingly in a third direction. The plurality of layers forming a three-dimensional structure comprising a plurality of hollow channels extending in the third direction, wherein the implant is compressible at least along the third direction. Each hollow channel comprises a first sidewall extending in the third direction and comprises a plurality of strand segments oriented in a first direction and a plurality of gaps arranged alternatingly, and a second sidewall extending in the third direction and comprising a plurality of strand segments oriented in the second direction and a plurality of gaps arranged alternatingly. At least one of the first sidewall and the second sidewall of the hollow channel is an undulating sidewall. The plurality of strand segments of the undulating sidewall belong to different layers of the implant. Adjacent strand segments of the undulating sidewall are separated by a gap. The adjacent strand segments have a lateral offset with respect to each other to create a pattern of a plurality of peaks and a plurality of troughs of the undulating sidewall.

Although not being part of the invention, further disclosed herein is a method of tissue reconstruction or tissue augmentation, wherein the method comprises implanting into the body of a subject an implant as defined herein.

The foregoing and other features of the present disclosure will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. It is understood that the accompanying drawings depict only several embodiments in accordance with the present disclosure and are, therefore, not to be considered limiting of its scope. The disclosure will be described with additional specificity and detail through use of the accompanying drawings, such that the advantages of the present disclosure can be more readily ascertained, in which:.

In the following detailed description, reference is made to the accompanying drawings that show, by way of illustration, specific embodiments in which the claimed subject matter may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the subject matter. It is to be understood that the various embodiments, although different, are not necessarily mutually exclusive. For example, a particular feature, structure, or characteristic described herein, in connection with one embodiment, may be implemented within other embodiments without departing from the spirit and scope of the claimed subject matter. References within this specification to "one embodiment" or "an embodiment" mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one implementation encompassed within the present description. Therefore, the use of the phrase "one embodiment" or "in an embodiment" does not necessarily refer to the same embodiment. In addition, it is to be understood that the location or arrangement of individual elements within each disclosed embodiment may be modified without departing from the spirit and scope of the claimed subject matter. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the subject matter is defined only by the appended claims, appropriately interpreted, along with the full range of equivalents to which the appended claims are entitled. In the drawings, like numerals refer to the same or similar elements or functionality throughout the several views, and that elements depicted therein are not necessarily to scale with one another, rather individual elements may be enlarged or reduced in order to more easily comprehend the elements in the context of the present description.

The terms "over", "to", "between" and "on" as used herein may refer to a relative position of one layer with respect to other layers. One layer "over" or "on" another layer may be directly in contact with the other layer or may have one or more intervening layers. One layer "between" layers may be directly in contact with the layers or may have one or more intervening layers. The phrase "A, B and/or C" as used herein may mean "A", "B", "C", "A and B", B and C", "A and C", and "A and B and C".

<FIG> and <FIG> show respectively perspective and cross-sectional side-view illustrations of an implant <NUM> for insertion into a patient.

As shown in <FIG>, the implant <NUM> comprises a plurality of strands <NUM> forming a three-dimensional structure <NUM>. The three-dimensional structure <NUM> comprises a plurality of hollow channels <NUM>. Each hollow channel <NUM> comprises a plurality of sidewalls <NUM>. A sidewall <NUM> comprises a plurality of strand segments <NUM> and a plurality of gaps <NUM> (shown in <FIG>) arranged alternatingly so that a gap <NUM> is formed between adjacent strand segments <NUM> of the sidewall <NUM>. The plurality of gaps <NUM> are reversibly expandable gaps.

Generally, a hollow channel <NUM> may be formed by at least three sidewalls contiguous with each other (or e.g. intersecting each other) so that a hollow space is enclosed by the sidewalls. In the example of <FIG>, a plurality of hollow channels <NUM>, each having a square cross-section is shown. A (or each) hollow channel <NUM> with a square cross-section may have four intersecting sidewalls <NUM>.

<FIG> shows a cross-sectional side view illustration of the implant <NUM> through the line A-A'. The side-view illustration shows a plurality of strands (also referred to as filaments) <NUM> of the three-dimensional structure <NUM>, wherein the plurality of (parallel) strands <NUM> form sidewalls <NUM>, 104A of two adjacent (e.g. directly adjacent) channels <NUM>, 103A of the three-dimensional structure <NUM>. As shown in <FIG>, and taking hollow channel 103A as an example, the hollow channel 103A may include a first sidewall 104A (shown as a sidewall parallel to the page) formed from the plurality of parallel strands <NUM>. The hollow channel 103A my further include a second sidewall 104B (shown as strands going into and/or out of the page), a third sidewall 104C (shown as strands going into and/or out of the page) and a fourth sidewall (not shown). The third sidewall 104C may be an opposite facing sidewall to the second sidewall 104B. Both the second sidewall 104B and the third sidewall 104C may be contiguous to the first sidewall 104A and the fourth sidewall. The fourth sidewall may be an opposite facing sidewall to the first sidewall 104A. Where the sidewalls intersect, their strands may be cross-cross each other in an alternating fashion.

A (or each) sidewall <NUM> of a channel <NUM>, such as the sidewall 104A of the hollow channel 103A may include a plurality of consecutive strand segments 105A arranged consecutively in the z-direction (vertical). Each strand segment 105A may be a portion (or segment) of a longer continuous strand <NUM> forming parts of other sidewalls <NUM> or channels <NUM>. Optionally, the plurality of consecutive strand segments 105A forming the sidewall 104A of the hollow channel 103A may be substantially parallel to each other. Each sidewall 104A may further include a plurality of gaps 106A.

The plurality of gaps 106A and the plurality of strand segments 105A of the hollow channel 103A may be arranged alternatingly, such that a (e.g. one) gap 106A may be located between adjacent (e.g. directly consecutive) strand segments 105A of the sidewall 104A (e.g. between two successive strand segments 105A of the sidewall 104A). Adjacent (e.g. directly adjacent, or e.g. successive) strand segments may be separated by a gap 106A.

<FIG> shows a gap 106A between two adjacent strand segments 105A of a (one, single) sidewall 104A of the hollow channel 103A of the implant <NUM>.

The gap 106A may also be referred to as a slit and/or a spacing, and refers to a blank space between the lengths of two adjacent strand segments 105A. The gap 106A may be defined by two pairs of intersecting strands <NUM> forming a perimeter of the gap 106A (e.g. bordering, or e.g. enclosing the gap 106A). The first pair of strands segments 105A (parallel to the y-direction) of the first sidewall 104A may be opposite facing strands and/or may optionally be substantially parallel to each other. The second pair of strand segments 105B, 105C may be opposite facing strands of the second sidewall 104B and the third sidewall 104C and may be substantially parallel to each other. The gap 106A may be the area enclosed by the two pairs of intersecting strands. The first pair of strand segments 105A forming the gap 106A may be adjacent strand segments 105A of the same (first) sidewall 104A of the hollow channel 103A. The second pair of strand segments may be opposite strands of the second sidewall 104B and the third sidewall 104C.

The gap 106A may have, or may be defined by a baseline gap height, h. The baseline (or resting) gap height, gh, may be a minimal (or smallest) height between the two adjacent strand 105A when the implant <NUM> is at rest. Additionally, or alternatively, the baseline gap height, gh, may be a height of the gap 106A at a mid-point region of the gap 106A (e.g. at a mid-point region of the strand segments 105A of the gap 106A. Additionally or alternatively, the baseline gap height may be an average (mean) gap height of more than <NUM> % of the gaps of the implant when the implant is at rest. Additionally, the gap 106A may have, or may be defined by a baseline gap length, gl, which is the maximal (or largest) dimension of the gap 106A. Additionally, the base line gap length, gl, may be the length of the strand segment between the second pair of strands 105B, 105C, such as between the two closest edges of the first strand 105B and the second strand 105C (<FIG>), or alternatively, from center of the first strand 105B to the center of the second strand 105C (<FIG>). The second pair of strands may be fused to the first pair of strand segments where the two pairs intersect, and the second pair of strands may form a simple support for the first pair of strand segments at opposite ends of the gap length, gl.

The two pairs of intersecting strands <NUM> may be fused or joined at the intersection areas. Additionally or optionally, opposite facing strand segments 105A may have some sag or droop so that the baseline gap height, gh, is equal to or less than the average strand diameter, d. When the gap height is expanded, (e.g. by inserting a needle through the gap) the shape of the gap <NUM> may be changed, or modified. Optionally, the area enclosed by the two pairs of intersecting strand segments 105A, 105B, 105C may remain unchanged. Alternatively or optionally, the area enclosed by the two pairs of intersecting strands <NUM> may increase to more than <NUM> % (or e.g. more than <NUM> %, or e.g. more than <NUM> %, or e.g. more than <NUM> %, or e.g. between <NUM> % and <NUM> %, or e.g. between <NUM> % and <NUM> %) of the originally enclosed area.

<FIG> also illustrates a spring-like character of a reversibly expandable gap <NUM> (such as gap 106A). If a tension force (indicated by the opposing arrows <NUM>, <NUM>) is applied to the opposite facing strand segments 105A of the gap 106A, the gap height, gh, increases. Additionally, each of the opposite facing strand segments 105A of the gap 106A may experience opposing tensional forces. When the tension forces are applied to the strand segments 105A of the gap 106A, the gap 106A may be configured to be expandable with respect to the baseline gap height, gh. For example, the reversibly expandable gap <NUM> may be expandable to more than <NUM> % (or e.g. more than <NUM> %, or e.g. more than <NUM> %, or e.g. more than <NUM> %, or e.g. between <NUM>% and <NUM>%, or e.g. between <NUM> % and <NUM> %, or e.g. between <NUM> % and <NUM> %) of the baseline gap height, gh and/or average strand diameter, d. The reversibly expandable gap 106A may recover or return to its original (resting) gap height after the tension forces (<NUM>, <NUM>) are removed from the strands 105A of the gap 106A (even at the same ambient pressure and temperature). For example, the reversibly expandable gap <NUM> may be configured to recover or return to less than <NUM> % (or e.g. to less than <NUM> %, or e.g. to <NUM> %, or e.g. between <NUM> % and <NUM> %, or e.g. between <NUM> % and <NUM> %) of its original gap height, gh, and/or average strand diameter, d, after the tension forces exerted on the strands 105A has been removed.

Optionally, the baseline gap length, gl may be more than <NUM> times (or e.g. more than <NUM> times, or e.g. more than <NUM> times) larger than the baseline gap height, gh. Optionally, a baseline gap height, gh, may lie between <NUM> and <NUM> (or e.g. between <NUM> and <NUM>, or e.g. between <NUM> and <NUM>). Optionally, an average thickness of the plurality of strands <NUM> may lie between <NUM> and <NUM> (or e.g. between <NUM> and <NUM>, or e.g. between <NUM> and <NUM>). Optionally, the baseline gap length, gl may be more than <NUM> times (or e.g. more than <NUM> times, or e.g. more than <NUM> times) larger than the diameter, d, (or thickness) of the strands <NUM>. For example, the baseline gap length, gl may be less than <NUM> (or e.g. between <NUM> and <NUM>). Optionally a baseline gap height, gh, may lie between <NUM> % to <NUM> % (or e.g. between <NUM> % and <NUM> %, or e.g. between <NUM> % and <NUM> %) of the average (mean) strand diameter, d, of the strands <NUM> of the implant. It may be understood that although <FIG> shows only one respective strand segment 105B, 105C of each of the second sidewall 104B and the third sidewall 104C, more than one strand of each of the second sidewall 104B and the third sidewall 104C may be arranged between the first pair of strand segments 105A of the first sidewall 104A. In which case, the baseline gap height, gh, may depend on the total thickness in the z-direction of the second pair of strands. For example, the baseline gap height, gh, may lie between <NUM> % to <NUM> % (or e.g. between <NUM> % and <NUM> %, or e.g. between <NUM> % and <NUM> %) of the total thickness in the z-direction of the second pair of strands.

As shown in <FIG>, each hollow channel <NUM>, 103A may include at least the first sidewall 104A comprising a first plurality of consecutive strand segments 105A and a first plurality of reversibly expandable gaps <NUM>. The hollow channel 103A may further include a second sidewall 104B comprising a second plurality of consecutive strand segments and a second plurality of reversibly expandable gaps. The second sidewall 104B may be contiguous to the first sidewall 104A. The strand segments 105A of the first plurality of consecutive strand segments 105A and strand segments 105B of the second plurality of consecutive strand segments 105B may be arranged alternatingly in a direction between a first end <NUM> of a longitudinal axis of the hollow channel 103A and second end <NUM> of the longitudinal axis of the hollow channel 103A.

The two sidewalls <NUM>, 104A of the adjacent channels <NUM>, 103A may be separated (or divided) by the further sidewall 104B. The further sidewall 104B may comprise a plurality of strands (shown in <FIG> to be going into the page). The strands of the further sidewall 104B may intersect the strands <NUM> forming the sidewalls 104A, 104A. The channels of the plurality of hollow channels <NUM> may be arranged adjacently (e.g. directly adjacently) to each other. The adjacent channels 103A, 103B may share the common sidewall 104B.

The implant <NUM> may have different sizes depending on the purpose of the implant. In the x-direction, the implant may have a dimension of up to <NUM> (or e.g. between <NUM> and <NUM>, or e.g. between <NUM> and <NUM>). In the y-direction, the implant may have a dimension of up to <NUM> (or e.g. between <NUM> and <NUM>, or e.g. between <NUM> and <NUM>). In the x-direction, the implant may have a dimension of up to <NUM> (or e.g. between <NUM> and <NUM>, or e.g. between <NUM> and <NUM>).

The plurality of strands <NUM> of the three-dimensional structure <NUM> of the implant <NUM> may constitute (or may make up) a material volume of the implant. The material volume occupied by the plurality of strands <NUM> may lie between <NUM> % and <NUM> % (or e.g. between <NUM> % and <NUM> %, or e.g. between <NUM> % and <NUM> %) of the total resting implant volume. Additionally, or optionally, the gaps <NUM> of the implant may constitute (or may include) between <NUM> % and <NUM> % (or e.g. between <NUM> % and <NUM> %, or e.g. between <NUM> % and <NUM> %) of the total resting implant volume. Of the material volume of the three-dimensional structure <NUM> of the implant, the plurality of sidewalls <NUM> of the implant may constitute (or may include) between <NUM> % to <NUM> % of the material volume. The rest of the material volume of the implant <NUM> which is not formed by the plurality of sidewalls <NUM> may be contributions from contouring lines and/or surface filler lines, for example. Optionally, the strand segments <NUM> of a sidewall <NUM> may constitute (or may make up) less than <NUM> % (or e.g. less than <NUM> %, or e.g. between <NUM> % and <NUM> %, or e.g. between <NUM> % and <NUM> %) of the sidewall <NUM>, with the rest being of the sidewall <NUM> being occupied by the gaps <NUM>. Optionally, at least <NUM> % (or e.g. at least <NUM> % or e.g. <NUM> %) of all the sidewalls <NUM> of the plurality of sidewalls <NUM> may include the reversibly expandable gaps <NUM>. Additionally or optionally, at least <NUM> % (or e.g. at least <NUM> %, or e.g. at least <NUM> %) of all the gaps <NUM> of the implant <NUM> are reversibly expandable gaps.

As shown in <FIG>, the implant <NUM> may form (or may be) a three-dimensional structure <NUM>, which may be a mesh-like structure or scaffold structure. For example, the plurality of strands <NUM> (or lines) may be configured to form the mesh-like three-dimensional structure <NUM>. The three-dimensional structure <NUM> may define (or may have) the resting volume of the implant <NUM>. The resting volume (cm<NUM>) of the implant <NUM> may be the volume of the implant <NUM> before inserting the implant <NUM> into the patient to construct and/or reconstruct soft tissue. The resting volume of the implant <NUM> may be the volume of the implant <NUM> at rest. An implant <NUM> at rest may be the state of the implant wherein only one outer surface (e.g. outer surface <NUM>) of the implant <NUM> experience an external force, such as when the implant <NUM> is at rest on (or in contact with, or seated on) a carrier surface (e.g. a table surface, or e.g. a board). For example, an implant <NUM> at rest may mean that a first outer surface <NUM> of the implant may be in contact with the carrier surface, and a second (opposite facing) outer surface <NUM> may be free from any tensional and/or compressive forces. In other words, the resting volume of the implant <NUM> may be the volume of the implant <NUM> without opposing compressive or tensional forces acting on the surfaces of the implant. The resting volume of the implant <NUM> may be derived based on a construction volume (the desired or required volume) of the implant <NUM> to be inserted into the patient. For example, optionally, the implant <NUM> may be configured to be compressible to less than the construction volume, so that the implant <NUM> comprises or attains the construction volume after insertion into the patient.

The plurality of strands <NUM> may be a plurality of lines, or string-like material. A strand <NUM> (or line, or filament) may have a length and a cross-sectional diameter, d. The diameter of the strand <NUM> may be the average dimension of the strand <NUM>, such as the smallest cross-sectional dimension of the strand <NUM>. Optionally, the length of the strand <NUM> may be larger (e.g. at least <NUM> times larger, or e.g. at least <NUM> times larger, or e.g. at least <NUM> times larger) than the diameter of the strand <NUM>. The strand diameter may optionally be between <NUM> and <NUM>, for example.

The term hollow channel <NUM> may refer to a channel wherein at least <NUM> % (or e.g. at least <NUM> %, or e.g. at least <NUM> %) of the channel volume enclosed by the sidewalls of that channel is unfilled or unoccupied by any material such as strand segments or strands. For example, the hollow channel <NUM> may not necessarily be limited to being a completely (<NUM> %) unfilled channel.

The three-dimensional structure <NUM> may include a plurality of substantially planar layers (e.g. parallel to the x-y plane) arranged or stacked successively over (on top of) each other in the z-direction <NUM> (e.g. vertical direction). Optionally, each planar layer may include a plurality of strands <NUM> forming a two-dimensional lattice arrangement of unit cells. The individual layers of the implant <NUM> may be arranged successively (stacked and/or one above the other), such that the unit cells of successive layers (formed on top of each other) may form the plurality of hollow channels <NUM>. Each channel <NUM> may be formed from (or may include) a column of unit cells from successive layers stacked on top of each other. For example, in the implant <NUM> shown in <FIG>, the implant <NUM> may include predominantly square-shaped unit cells of a plurality of layers arranged on top of each other to form hollow channels <NUM> having a square-shaped cross-section. Optionally, the unit cells may be repeated regularly throughout more than <NUM> % (or e.g. more than <NUM> %, or e.g. more than <NUM> %, or e.g. more than <NUM> %) of the resting volume of the three-dimensional lattice structure <NUM>. The lattice structure <NUM> may thus include a plurality of adjacent (e.g. directly adjacent) unit cells, connected to each other throughout the lattice structure <NUM>. A unit cell may be the smallest and most basic unit of the three-dimensional lattice structure <NUM>.

Optionally, each planar layer of unit cells may include a first sublayer (or a first group of sublayers) including strands oriented in a first direction, and an adjacent second sublayer (or second group of sublayers) of strands oriented in a second direction different to the first direction.

<FIG> show a first sublayer of an implant <NUM>, the first sublayer <NUM> including strands <NUM> oriented in the first direction (e.g. a y-direction). <FIG> show a second sublayer <NUM> of an implant <NUM>, the first sublayer <NUM> including strands <NUM> oriented in the second direction (e.g. a x-direction). Optionally, the strands <NUM> within each respective sublayer may be parallel to each other (e.g. an acute angle between the strands within a sublayer, or between the strand of best fit for sinusoidal strands, may lie within +/ - <NUM>°). The plurality of strands <NUM> of the first sublayer <NUM> and the plurality of strands <NUM> of the second sublayer <NUM> may intersect at intersection points or intersection regions to form the two-dimensional lattice arrangement of a layer. Optionally, the strands <NUM> of (or e.g. within) each sublayer <NUM>, <NUM>, may be part of a continuous strand meandering continuously from a start point, S, of the sublayer to an end point, E, of the sublayer. For example, optionally, the strands of the first sublayer <NUM> may be part of a continuous sublayer strand meandering continuously from the start point, S, to the end point, E, of the first sublayer. Optionally, the strands of the second sublayer <NUM> may be part of a continuous sublayer strand meandering continuously from the start point, S, to the end point, E, of the second sublayer. A continuous strand of a sublayer may have a plurality of straight portions oriented in a first direction. A plurality of straight portions of a sublayer may be connected by meandering portions. The meandering portions may be formed at least partially on the boundary or perimeter of the layer, and may form surface filler lines or a sidewall of a channel at the surface of the implant. Each sublayer may have its own boundary or perimeter at which meandering portions (or surface filler lines are formed). Optionally, the strands may be straight strands, or alternatively, the strands may be sinusoidal zig-zag strands, wherein the unit cells may have a "free-form" shape.

The first sublayer <NUM> and the second sublayer <NUM> may be arranged such that their respective strands <NUM> intersect to form the two-dimensional lattice arrangement of unit cells. The intersecting strands <NUM> of the first sublayer <NUM> and the second sublayer <NUM> may be arranged, so that each unit cell formed from the intersecting strands may include or may be referred to as a pore, having a pore size. The intersecting strands may form or define a geometry (e.g. shape, dimension, pore size) of the individual unit cells. Each two-dimensional unit cell may have a pore size, defining the dimension of the unit cell. The pore size of the two-dimensional unit cell may be described in terms of its diameter, width and/or pore area, For example, the pore size, w, of the unit cell of a layer may be referred to as the diameter or width of the hollow channel <NUM> (as shown in <FIG>). Optionally, an average pore size of the plurality of unit cells of the three-dimensional structure <NUM> may be at least <NUM> (or e.g. at least <NUM>, or e.g. at least <NUM>, or e.g. at least <NUM>, or e.g. at least <NUM>, or e.g. at least <NUM>, or e.g. at least <NUM>). A pore area of at least <NUM> % (or e.g. at least <NUM> %, or e.g. at least <NUM> %) of the surface pores of the three-dimensional structure <NUM> may be at least <NUM><NUM> (or e.g. at least <NUM><NUM>, or e.g. at least <NUM><NUM>). The surface pore area may be the area enclosed by intersecting strands defining a surface pore.

The plurality of two-dimensional unit cells may be polygonal-shaped, triangular-shaped unit cells, diamond-shaped unit cells, rhomboid-shaped unit cells, square-shaped unit cells, ellipsoidal shaped, sinusoidal shaped, and/or hexagonal shaped unit cells. It may be understood that the implant <NUM> may optionally include unit cells have predominantly (e.g. more than <NUM> %, or e.g. more than <NUM> %, or e.g. more than <NUM> %, or e.g. more than <NUM> %) one of those shapes throughout the volume of the implant <NUM>, or alternatively, the implant <NUM> may include unit cells with a variety of different shapes. A sidewall <NUM> of the hollow channel <NUM> may be formed from the plurality of strands <NUM> lying substantially parallel to the x-y plane, vertically stacked in the z-direction (third direction), and oriented substantially in the same direction. The sidewalls <NUM> of a hollow channel <NUM> may be arranged such that a cross-section shape of the hollow channel <NUM> is one of the shapes from the following group of shapes: polygon, triangle, diamond, rhomboid, square, ellipsoid, and sinusoidal, and hexagonal.

In comparison to the pores, the gaps <NUM> of the implant <NUM> may refer to (or may be) the smallest spacings between any adjacent strands forming the hollow channel <NUM>. For example, the gaps <NUM> may have the smallest area enclosed by strands of the implant (e.g. smallest gap area), compared to the pore size area of the unit cells. Optionally, a gap area of a gap <NUM> (which may the area enclosed by the two pairs of opposing strands defining the gap <NUM>), may be less than <NUM> % (or e.g. less than <NUM> % or e.g. less than <NUM> %) of the pore size area.

Each hollow channel <NUM> may extend along a longitudinal axis of the hollow channel <NUM>. The longitudinal axis may be a line including the mid-points of the sidewalls of the hollow channel <NUM>. The hollow channels <NUM> may extend between the first outer surface region <NUM> and a second outer surface region <NUM> of the three-dimensional structure <NUM>, for example. A channel <NUM> (e.g. optionally, each channel, or e.g. one or more channels <NUM>) of the plurality of hollow channels <NUM> may be configured to extend from the first outer surface region <NUM> towards the second outer surface region <NUM>. The exact positions and/or tilt angles of the plurality of hollow channels <NUM> may be configured according to the needs of the patient. Optionally, the plurality of hollow channels <NUM> may be parallel to each other (e.g. an acute angle between the sidewalls of adjacent channels may lie within +/ - <NUM>°). Alternatively, the plurality of hollow channels <NUM> may converge towards a region (or point) of convergence, wherein the region of convergence is located outside the first outer surface region <NUM> or the second outer surface region <NUM>. Optionally, the hollow channels <NUM> may include zig-zag channels, slanted channels and/or tapered channels. Optionally, the hollow channels <NUM> may be channels slanted with respect to the first outer surface region <NUM>. For example, of the unit cells forming the column of unit cells, a unit cell of a second layer may have a lateral offset (in the x-direction or y-direction) with respect to a unit cell of an adjacent first layer. The lateral offset value between the first unit cell and the second unit cell may lie between <NUM> % and <NUM> % (or e.g. between <NUM> % and <NUM> %, or e.g. between <NUM> % and <NUM> %) of a pore size of the unit cell. Optionally, within the same column, a unit cell of each layer may have the same lateral offset with respect to a unit cell of a directly previous layer. Optionally, at least <NUM> % (or e.g. at least <NUM> %, or e.g. at least <NUM> %) of the unit cells of the same column (forming the same channel) may have the same pore size and the same pore shape. Alternatively, in the case of tapered channels, unit cells forming the same channel may have different pore sizes (e.g. the pore sizes of the unit cells may decrease or increase towards one of the outer surface regions).

The plurality of strands <NUM> may be configured such that the gap 106A is reversibly expandable when the implant is at rest and/or even when the implant <NUM> is under compression. When a (physical or mechanical) compression force is exerted on more than one outer surface of the implant <NUM>, the implant <NUM> may be compressible to less than <NUM> % (or e.g. less than <NUM> %, or e.g. less than <NUM> %, or e.g. less than <NUM> %, or e.g. less than <NUM> %, or e.g. between <NUM> % and <NUM> %, or e.g. between <NUM> % and <NUM> %, or e.g. between <NUM> % and <NUM> %, or e.g. between <NUM> % and <NUM> %) of its resting volume.

The expandability of the gaps of the implant may be explained with reference to a deflection of a beam. The gaps of the implant may be expandable, meaning that the strands are able to deflect and/or bend, without breaking, in response to one or more forces exerted on the strand, such that the gap height between two adjacent strand segments increases. A bending stress σ of a beam (or strand segment) undergoing simple bending in response to an applied external force may be expressed as <MAT>.

As shown in <FIG>, such a beam may be simply supported at both ends, and the bending moment may be a reaction induced in the beam when the external force or moment is applied to the beam. σ may be the bending stress. M may be the bending moment, c may be the distance from the neutral axis. I may be the moment of inertia of the beam cross-section. The maximum bending moment M caused by a centrally applied load between the supports may be described or defined by the equation <MAT>.

L may be the length of the beam and F may be the force exerted on the beam. A maximum bending stress, σmax may be represented by the equation <MAT>.

M may be the maximum bending moment, cmax may be the maximum distance from the neutral axis. I may be the moment of inertia of the beam cross-section. Deflection, δ, of a centre load on a beam with two simple supports may be described by <MAT>.

L may be the length of the beam, F may be the force exerted, E may be the Young's Modulus and I may be the moment of inertia of the beam. When considering the implant <NUM>, the deflection capability, δ, of a strand of an implant may result in an expanding gap. The deflection capability may reflect or may be a desired deflection capacity of the strand, and/or a desired expandability of the gap height (e.g. how much a gap is expected to expand by).

<FIG> shows an illustration of the implant illustrated in <FIG>. As shown in <FIG>, the insertion of a needle <NUM> into the gap may exert one or more forces <NUM>, <NUM> on the implant. The needle may have a diameter, nd, which may be larger than the baseline gap height, gh. The gap length, may be represented by gl, which may be the length of the strand segment between the center of the first strand 105B and the center of the second strand 105C. The first strand and second strand 105C may act as simple supports for the adjacent strand segments <NUM> of the gap.

The insertion of the needle results in deflection, δ in each of the two consecutive strand segments 105a. Each strand segment 105a may behave like a beam with two simple supports 105B, 105c undergoing a bending stress. A deflection of the adjacent strand segments 105A caused by the insertion of the needle may be represented by the dotted lines. The deflection may be represented by the equation <MAT>.

The maximum bending stress of a strand which may be subject to a force, such as by insertion of the needle <NUM>, may be <MAT>.

R may be the radius of the strand (e.g. d = <NUM> × R).

Using equations (<NUM>) and (<NUM>), <MAT> and an equation for maximum stress, σmax, may be obtained: <MAT>.

A rule may be applied for elastic deformation, such that the value of σmax does not exceed σyield, which is the yield strength of the material of the strand. Thus, <MAT>.

The deflection capability, δ, may be represented by the equation <MAT>.

The reversibly expandable gap <NUM> may be expandable to between <NUM> % and <NUM> % of the baseline gap height, gh. This may occur, if a needle diameter, nd, is between <NUM> % and <NUM> % of the base line gap height, gh. These parameters may be expressed by the equation <MAT> and <MAT>.

E and σyield are material properties of the strand material of the implant <NUM>. R, the radius of the strand, and gl, the length of the strand segment between the two supports 105B, 105C are geometric features of the strands of the implant <NUM>. Equation (<NUM>) may be obtained based on equation (<NUM>).

<FIG> shows an illustration of the adjacent strands 105A of <FIG> in the z-x cross-section. In some examples, the lateral offset of one strand segment 105A with respect to its adjacent strand segment 105A in the subsequent layer is equal to zero (offset= <NUM>) along (or horizontal to) the x-y plane. In these cases, the baseline gap height, gh, may be simply equal to the average strand diameter, d or 2R.

Alternatively, as shown in <FIG>, there may be cases wherein the lateral offset of one strand segment 105A with respect to its adjacent strand segment 105A in the subsequent layer along or horizontal to the x-y plane is greater than zero. In such cases, the gap height, gh, may be expressed as <MAT>.

lt may be referred to as a layer thickness. The dimension <NUM> × lt may be the distance measured in the z-direction between a mid-point of the first strand segment 105A and the mid-point of the second adjacent strand segment 105A. The dimension <NUM> × lt, may be an offset in a z-direction, whereas the lateral offset may be an offset in a x or y direction. The lateral offset value between the adjacent strand segments may lie between <NUM> % and <NUM> % (or e.g. between <NUM> % and <NUM> %, or e.g. between <NUM> % and <NUM> %) of gap length, gl.

<FIG> show respectively perspective and cross-sectional side-view illustrations of an implant <NUM> for insertion into a patient. The implant <NUM> may include one or more or all of the features described in connection with <FIG>. The implant <NUM> may have different dimensions compared to the implant <NUM>, such as a different gap height to gap length ratio. For example, the baseline gap height, gh, may be similar to the baseline gap length, gl (e.g. between <NUM>% and <NUM>% of the base line gap length).

The implant <NUM>, <NUM> may be any type of implant suitable for insertion into a patient, which may be a living body (e.g. a human body, or e.g. an animal body). The implant <NUM>, <NUM> may be a scaffold for bone tissue or implant for any soft-tissue part of the human or animal body. The implant might be a breast or thorax implant (the latter may be uses for treatment of pectus malformation such as pectus excavatum), or for other parts of the body, such as the gluteal region (also known as buttock), the calf, parts of the face such as a cheek, or a testicular implant. In this context, it is noted here, that pectus malformation such as pectus excavatum can affect both males and females and thus pectus excavatum of both a male and a female subject both can be treated by an implant of the invention. In line with the above, an implant of the invention can adopt any suitable form, merely depending on the tissue that is to be reconstructed or augmented. The implant may, for example, have the form of a gluteal implant as described in <CIT>. Dependent on the type of implant required, the geometry of the implant <NUM>, <NUM> (e.g. the size and/or the shape of the implant) may be tailored to meet the criteria required of the implant.

<FIG> shows a perspective illustration of an implant <NUM> suitable for use as breast implant. The implant <NUM> may include one or more or all of the features of the implants described in connection with <FIG>. Although the implant <NUM> is described with respect to breast implants, such an implant may also be valid for other parts of the body, such as the thorax, the gluteal region, the calf, or parts of the face such as a cheek (cf, above).

As shown in <FIG>, the implant <NUM> comprises a plurality of strands <NUM> forming a three-dimensional structure <NUM>. The three-dimensional structure <NUM> comprises a plurality of hollow channels <NUM>. Each hollow channel <NUM> comprises a plurality of sidewalls <NUM>. A sidewall <NUM> comprises a plurality of strand segments <NUM> and a plurality of gaps <NUM> arranged alternatingly so that a gap <NUM> is formed between adjacent strand segments <NUM> of the sidewall <NUM>. The plurality of gaps <NUM> are reversibly expandable gaps.

The three-dimensional structure <NUM> of the implant <NUM> may include a first outer surface region <NUM> and a second (different and/or opposite facing) outer surface region <NUM>. It may be understood that an outer surface region may refer to (or may be) an outermost surface, an outermost layer, and/or an outermost contour of the implant <NUM>. An outermost surface and outermost contour may be formed from one or more layers or lines. An outer surface region may refer to (or may be) an outermost group of layers (e.g. a single outermost layer, or e.g. an outermost plurality of layers) of the implant <NUM>. An outer surface region may refer to an exterior facing surface of the implant <NUM>.

The first outer surface region <NUM> of the implant <NUM> may include, or may have a first surface curvature. The first outer surface region <NUM> of the implant <NUM> may be the largest planar (or e.g. flattest) surface of the implant <NUM>. For example, the first outer surface region <NUM> may be a flattest surface of the implant and/or surface with the least (or smallest) amount of curvature. As shown in <FIG>, the first outer surface region <NUM> of the implant <NUM> may be substantially parallel to a two-dimensional (x-y) cartesian plane. Alternatively, or optionally, a plane of best fit of the first outer surface region <NUM> may be parallel to the two-dimensional (x-y) cartesian plane.

The second outer surface region <NUM> may have a geometry (e.g. the shape, curvature, size) which represents a geometry of a patient's breast to be constructed by the implant <NUM>. The second outer surface region <NUM> of the implant <NUM> may include, or may have a second surface curvature different to the first surface curvature. The second surface curvature may be greater than the first surface curvature. The second outer surface region <NUM> of the implant <NUM> may be contiguous to (e.g. abutting) the first outer surface region <NUM> of the implant <NUM> at a perimeter <NUM> (e.g. a circumference) of the first outer surface region <NUM>. For example, second outer surface region <NUM> of the implant <NUM> may abut the first outer surface region <NUM>, wherein the perimeter <NUM> of the first outer surface region <NUM> may be a shared edge (or interface) between the first outer surface region <NUM> and the second outer surface region <NUM>. Additionally, or optionally, the second outer surface region <NUM> may include an apex region <NUM> at the second outer surface region <NUM>. The location (or position) of the apex region <NUM> at the second outer surface region <NUM> of the implant may be based on (and/or may coincide with) the location (or position) of the nipple/areola of the breast to be constructed by the implant <NUM>.

Optionally, an acute tilt angle between one or more sidewalls and a reference axis (e.g. an x-axis) representing the first outer surface region may be less than <NUM> degrees (or e.g. less than <NUM> degrees). The reference axis may be based on a plane or line of best fit of the first outer surface region <NUM>. Optionally or alternatively, the acute tilt angle between one or more sidewall <NUM> and the reference axis may be approximately <NUM> degrees (e.g. as shown in <FIG>, the channels may be perpendicular channels). The plurality of hollow channels <NUM> may consist of between <NUM> and <NUM> hollow channels (or e.g. between <NUM> and <NUM> channels, or e.g. between <NUM> and <NUM> channels).

The three-dimensional structure <NUM> of the implant <NUM> may be a reversibly compressible three-dimensional structure <NUM>. For example, the individual unit cells of the implant <NUM> may be spring-like unit cells. A spring-like unit cell may be compressible to at least <NUM> % (or e.g. at least <NUM> %, or e.g. at least <NUM> %, or e.g. at least <NUM> %, or e.g. at least <NUM> %) of its original volume. By being reversibly compressible, each unit cell may be able to recover or return to its original (resting) volume after a compression force has been removed (even at the same ambient pressure and temperature). A reversibly compressible spring-like unit cell may be configured to recover to between <NUM> % and <NUM> % (or e.g. between <NUM> % and <NUM> %, or e.g. between <NUM> % and <NUM> %) of its original volume, after the compression force exerted on the implant <NUM> is removed.

The softness of the implant <NUM> may be represented by a c-value. The c-value may be expressed by the formula <MAT>.

F<NUM> % is the force value, in N, at a compression of <NUM> %, F<NUM> % is the force value, in N, at a compression of <NUM> %, ε<NUM> % is the strain value at a compression of <NUM> %, and ε<NUM> % is the strain value at a compression of <NUM> %. A c-value representing a softness of the implant <NUM> may lie between <NUM> N and <NUM> N (or e.g. between <NUM> N and <NUM> N, or e.g. between <NUM> N and <NUM> N, or e.g. between <NUM> N and <NUM> N), for example.

A material density, ρ, of the implant <NUM> may lie between <NUM> gr/cm<NUM> and <NUM> gr/cm<NUM>. (or e.g. between <NUM> gr/cm<NUM> and <NUM> gr/cm<NUM>, or e.g. between <NUM> gr/cm<NUM> and <NUM> gr/cm<NUM>). The material density may be determined by the weight of the implant <NUM> divided by the resting volume of the implant before insertion into the patient. In comparison, the material density of silicone is <NUM> gr/cm<NUM>, and the material density of saline is <NUM> gr/cm<NUM>. Thus, the weight of the implant of <NUM> may be between <NUM> % and <NUM> % (or e.g. between <NUM> % and <NUM> %) of its volume value in milliliters, and between <NUM> % and <NUM> % (or e.g. between <NUM> % and <NUM> %) of traditional non-porous silicone/saline implants (whose weights in grams are roughly the same as their volume value in milliliters). As an example, an implant <NUM> having a volume of <NUM> may weigh <NUM>, whereas a traditional silicone implant having a volume of <NUM>, may weight <NUM>, and a saline implant having a volume of <NUM>, may weigh <NUM>. One or more or all of these features leads to an implant having a lightweight scaffold, wherein a weight reduction of <NUM> % compared to traditional implants may be achieved.

The plurality of strands <NUM> of the implant <NUM> may be formed from a polymer material such as a surface-degradable polymer. A surface-degradable polymer material may include or may be a polymer material that degrades predominantly via the surface degradation mechanism as opposed to bulk degradation. The plurality of strands <NUM> may include or may be formed from or made of biodegradable material. The biodegradable material may be selected from the group consisting of polycaprolactone, poly(<NUM>,<NUM>-trimethylene carbonate), polylactide, polyglycolide, poly(ester amide), poly(ethylene glycol)/poly(butylene terephthalate), poly(glycerol sebacate), poly(<NUM>,<NUM>-octanediol-co-citric acid), poly(<NUM>,<NUM>-decanediol-co-D,L-lactic acid), poly(diol citrate), poly(glycolide-co-caprolactone), poly(<NUM>,<NUM>-trimethylene carbonate-co-lactide), poly(<NUM>,<NUM>- trimethylene carbonate-co-caprolactone) and a copolymer of at least two of these materials. Optionally, the biodegradable material may be polycaprolactone. Optionally, the biodegradable material may be a copolymer of polycaprolactone and either poly-trimethylene carbonate or polylactide. Alternatively, the plurality of strands <NUM> may include a non-degradable material such as nylon. The thickness (or diameter) of the plurality of strands <NUM> may be selected so that the strand is flexible. Bulk PCL, for example, may have an elastic modulus (E) of <NUM> MPa, a tensile strength of <NUM> MPa, and a breaking stress of <NUM> MPA.

The equation (<NUM>): <MAT> may be applied in the design of the implants described herein. <MAT> may be selected based on the material properties of a material (such as Young's modulus and yield strength) for forming the implant, and desired deflection capacity δ based on surgical requirements, such as the size of a needle used by a surgeon.

For example, a material used for forming the implant <NUM> may have an Elastic modulus of <NUM> MPa, and a yield strength σyield of <NUM> MPa. A needle to be used may have a diameter of <NUM>.

Geometrical properties related to the implant, such as lateral offset, layer thickness, radius and gap length may be chosen. For example, lateral offset may be <NUM>, a layer thickness, lt, may be <NUM>, a radius, R, may be <NUM> and a gap length, gl may be <NUM>.

Using equation (<NUM>): <MAT>, a value for gap height may be calculated or determined, wherein <MAT>.

Using equation (<NUM>): <MAT>, a value for deflection capacity may be calculated or determined, wherein <MAT>.

Using equation (<NUM>), a maximum limit for <MAT> may be calculated, wherein <MAT> <NUM>. <MAT>, which is less than the maximum limit <MAT>.

Additionally, or optionally, the implant <NUM> may further include a plurality of contouring strands <NUM> arranged at an outer surface region (e.g. at the second outer surface region <NUM>) of the implant <NUM>.

<FIG> shows a perspective side view illustration and a perspective top view illustration of an implant <NUM> further including a plurality contouring strands <NUM> and surface filler strands <NUM>.

As shown in <FIG>, the plurality of strands forming the implant <NUM> may include a plurality of contouring strands <NUM> and and surface filler strands <NUM>. Each contouring strand <NUM> may form a semi-contour around the second outer surface region <NUM>. The semi-contour of the contouring strands <NUM> may extend only partially (e.g. between <NUM> % and <NUM> %, or e.g. between <NUM> % and <NUM> %, or e.g. between <NUM> % and <NUM> %) around the perimeter of a layer. The plurality of contouring strands <NUM> may be arranged consecutively (e.g. successively) between the first outer surface region <NUM> and the apex region <NUM>. The plurality of contouring strands <NUM> may further be arranged such that adjacent contouring strands <NUM> are separated by a reversibly expandable gap <NUM>. For example, a reversibly expandable contouring gap <NUM> may be formed between adjacent strand segments of the plurality of contouring strands <NUM>.

As shown in <FIG>, the implant <NUM> may further include surface filler strands <NUM> formed at the outermost surface of the three-dimensional structure <NUM>. Optionally, the plurality of surface filler strands <NUM> may be arranged in columns <NUM> (or strips) at the second outer surface region. Each surface filler column <NUM> may include a plurality of surface filler strands <NUM> and a plurality of reversibly expandable surface gaps. Each reversibly expandable surface gap may be formed between adjacent surface filler strands <NUM> of a column <NUM>. A surface filler column <NUM> may be arranged adjacent to an open column <NUM>. An open column may include (or may be) a column of surface at the that are free from surface filler portions. Optionally, a plurality of surface filler columns <NUM> and a plurality of open columns <NUM> may be arranged alternatingly at the outer surface regions (e.g. at the second outer surface region <NUM>). Optionally a plurality of surface filler columns <NUM> and a plurality of open columns <NUM> may be arranged in a criss-cross fashion at the outer surface region.

The plurality of hollow channels <NUM> may extend through the bulk of the implant <NUM>. Adjacent strand segments may be separated by reversibly expandable gaps.

The implant <NUM> may be inserted into the breast region of a patient. After the insertion of the implant <NUM> into the patient, fat injection may need to be performed. Fat injection may be necessary because the regenerated tissue which "regrows" inside the implant has been observed to be stiffer than the natural breast tissue. Therefore, in order to make the final outcome as soft as natural breast tissue, a suitable percentage of fat may be collected, e.g. by means of liposuction, and injected into the implant <NUM> using a specific cannula (or needle). Due to reversibly expandable gaps <NUM> of the implant <NUM>, problematic aspects of the injection procedure (e.g. injections which perforate the structure several times and damage the strands and affect the integrity of the overall structure of the implant <NUM>) may be avoided.

The implant <NUM> may be an implant for use in guiding a needle through the implant for implant surgery. The implant <NUM> may be configured to receive an elongated object (such as a needle for fat injection) into the bulk of the three-dimensional structure <NUM>. The elongated object may have a diameter larger than a baseline gap height, gh, of the gaps <NUM> of the implant. For example, the diameter of the elongated object may be between <NUM>% and <NUM>% times the baseline gap height, gh, of the gaps <NUM> of the implant. Additionally, the elongated object may have a length greater than at least two times (or five times, or <NUM> times) a width of a hollow channel. The plurality of strands may be configured so that a height of the gap <NUM> increases due to the object being received by the gap, and the height of the gap <NUM> decreases due to the object being removed from the gap <NUM>. Such a needle or cannula may have a diameter of at least <NUM> (or e.g. at least <NUM>, or e.g. at least <NUM>, or e.g. between <NUM> and <NUM>, or e.g. between <NUM> and <NUM>), and a length of at least <NUM>. More than <NUM> % (or e.g. more than <NUM> %, or e.g. all) of all the gaps of the implant <NUM> having a baseline gap height of less than <NUM> may be reversibly expandable gaps.

<FIG> shows an implant without the reversibly expandable gaps of implants <NUM>, <NUM>, <NUM>.

Unlike the implants <NUM>, <NUM>, <NUM> with reversibly expandable gaps <NUM>, the implant of <FIG> would require that the surgeon insert the fat injection needle at precise locations. For example, after inserting the implant into the patient, the surgeon would have to visually locate the largest openings of the implant. These largest openings may be the channel pores defining the channel ends, whose pore size area may be at least <NUM> times larger than the gap area. Then, the surgeon would have to insert the needle precisely into the pores and along the channel length (e.g. along the longitudinal axis of the channel). If the surgeon is unable to visually locate the channel ends, or inserts the needle into the implant at an angle that is not along the channel length, or inserts the needle into a sidewall of the channel, the injections from the needle may damage the strands of the implant and/or damage the three-dimensional structure of the implant.

<FIG> shows an image of a cannula for fat injection being inserted into the implant <NUM>. With the implant <NUM>, it is possible for the surgeon to blindly insert the needle into the implant <NUM> from anywhere (e.g. any surface) of the implant. Due to the implant <NUM> having the reversibly expandable gaps <NUM>, the needle may be inserted into the breast implant from any direction at the second outer surface region <NUM> of the implant, and/or the needle may be inserted through any sidewall <NUM> within the bulk of the implant <NUM>. The needle may be first inserted through the bulk internal structure of the implant <NUM> from an insertion region of the implant <NUM>. The insertion region may be a randomly selected region of the implant. The needle may be inserted such that the needle concurrently crosses and/or enters several (e.g. a plurality of) hollow channels <NUM>, and penetrating through several (e.g. a plurality of) sidewalls. In other words, the needle may be concurrently inserted through a plurality of hollow channels <NUM>. The needle may then be withdrawn from the implant <NUM> in a step-wise function over a plurality of withdrawal steps. After each withdrawal step, fat from the needle may be injected into the implant. The alternating processes of withdrawing the needle and fat-injection, may be repeated until the needle is fully withdrawn from the implant. This process starting with blind injection may be carried out repeatedly from a plurality of random insertion regions. The number of times (e.g. at least <NUM> times, or e.g. at least <NUM> times, or e.g. at least <NUM> times) the process is carried out may be based on the number of injections required and/or the amount of fat injection required. The needle may need to be inserted very often during surgery. The implant <NUM> allows the surgical process to be sped up, since the surgeon no longer needs to visually locate each channel and opening before inserting the needle, and can instead carry out blind insertions. Furthermore, the implant <NUM> allows the cannula to penetrate a plurality of sidewalls <NUM> and channels <NUM> concurrently. This also allows the surgical process to be sped up. Furthermore, since the gaps <NUM> are able to accommodate the entry of the cannula, neither the implant <NUM> not the cannula suffers from damage. Thus, the inserted implant <NUM> has an improved structural integrity compared to implants <NUM> which have not implemented reversibly expandable gaps.

<FIG> shows an example of possible regions of insertions for multi-injections testing. A certain number of injections (e.g. <NUM> injections) may be divided over <NUM> broad injection sites (<NUM>, <NUM>, <NUM>). For example, <NUM> injections may be performed over each region. The injections (e.g. the insertion of the needle) may be carried out so that the needle may be inserted at any angle relative to the first outer surface region <NUM> of the implant. For example, the needle may be inserted in a flat plane, or at an angle of inclination or declination with respect to the first outer surface region <NUM>.

The plurality of strands <NUM> may be configured such that the gaps <NUM> of the implant <NUM> are reversibly expandable when the implant is at rest and even when the implant <NUM> is under compression (for example, even when the implant <NUM> is inside the body. An implant under compression may be an implant which has been compressed to less than <NUM> % (or e.g. less than <NUM> %, or e.g. less than <NUM> %, or e.g. less than <NUM> %, or e.g. less than <NUM> %) of its resting volume. A height of the gap <NUM> may increase to greater than <NUM> % (or e.g. greater than <NUM> %, or e.g. greater than <NUM> %, or e.g. between <NUM> % and <NUM> %, or e.g. between <NUM> % and <NUM> %) of the baseline gap height, gh, and/or the average strand diameter, d, due to the object being received by the gap <NUM>. The reversibly expandable gap <NUM> may be configured to recover or return (or decrease) to at least <NUM> % (or e.g. to at least <NUM> %, or e.g. to <NUM> %, or e.g. between <NUM> % and <NUM> %, or e.g. between <NUM> % and <NUM> %) of its original gap height, gh, and/or average strand diameter, d, due to the object being removed from the gap <NUM>.

To accommodate each insertion of the needle, the plurality of strands <NUM> may be arranged such that the reversibly expandable gaps <NUM> of at least two (or e.g. more than two, or e.g. more than three, or e.g. more than five) consecutive hollow channels may be concurrently expandable due to the object being received by the gaps of the at least two consecutive hollow channels concurrently. The plurality of strands <NUM> may be arranged such that reversibly expandable gaps <NUM> of at least two (or e.g. more than two, or e.g. more than three, or e.g. more than five) different sidewalls <NUM> of the implant <NUM> may be concurrently expandable due to the object being received by the gaps of the at least two (or e.g. more than two, or e.g. more than three, or e.g. more than five) different sidewalls concurrently. The expansion of the gaps <NUM> may occur even without increasing or changing the overall resting volume (or construction volume) of the implant <NUM>. In other words, the reversibly expandable gaps may be configured to expand, while the overall volume of the implant <NUM> remains constant or even under compression.

The surgeon inserting the needle should be able to penetrate the bulk of the implant without damaging the structure. For example, the filaments enclosing the gap may bend, stretch, or move out of the way and not break. Furthermore, the surgeon may exert not more than <NUM> N (or e.g. between <NUM> N and <NUM> N, or e.g. between <NUM> N and <NUM> N, or e.g. between <NUM> N and <NUM> N) of force to insert the needle through a gap. For example, upon being subjected to <NUM> N from the injection needle, the filaments reversibly deform (elongate or stretch or move) to allow the needle to pass through the gap. The material itself may be selected so that the filaments do not break at this elongation point.

<FIG> shows a stress strain curves of strands comprising different materials, such as stainless steel, polylactic acid plastic PLA and Polycaprolactone PCL.

A fracture point of a stainless steel strand may be at a strain of <NUM>% under a stress of <NUM> MPa. A fracture point of a PLA strand may be at a strain of <NUM>% when subjected to a stress of <NUM> MPa. The fracture point strain value for PCL strands is <NUM>% (under a stress of less than <NUM> MPa), which is approximately <NUM> times more than stainless steel strands and around <NUM> times more than the PLA strands. PCL accept high amount of deformation because of high Rupture strain, it means that it can be extended at least <NUM> times of its initial length.

The material for forming the plurality of strands may be selected such that it has a fracture point on a stress-strain diagram, wherein a strain at the fracture point is larger than <NUM>% and stress at the fracture point is less than <NUM> MPa.

The material of the strands of the implant may exhibit similar stress-strain behaviour as PCL. For example, the fracture point on the stress-strain diagram may be above <NUM> % (or e.g. above <NUM> %, or e.g. above <NUM> %, or e.g. above <NUM> %, or e.g. above <NUM> %), and the stress may be below <NUM> MPa, or between <NUM> MPa and <NUM> MPa (or e.g. between <NUM> MPa and <NUM> MPa, or e.g. between <NUM> MPa and <NUM> MPa, or e.g. between <NUM> and <NUM> MPa). Optionally, a fracture point of a strand of the plurality of strands may be larger than <NUM> % (or e.g. above <NUM> %, or e.g. above <NUM> %, or e.g. above <NUM> %, or e.g. above <NUM> %) and the corresponding stress may be below <NUM> MPa (or e.g. between <NUM> MPa and <NUM> MPa, or e.g. between <NUM> MPa and <NUM> MPa, or e.g. between <NUM> MPa and <NUM> MPa, or e.g. between <NUM> and <NUM> MPa).

As an example, if the distance between two neighboring strands varies between <NUM> and <NUM> and the needle diameter is <NUM>, during the penetration of the needle to the walls, PCL may deform easily without reaching to its rupture point. To the contrary, PLA and Stainless steel cannot take such a deformation and they would reach to the rupture point while needle penetration.

<FIG> shows an implant, such as the implant <NUM> after a mock surgery, During the mock surgery, the implant <NUM> was inserted inside a pig. The implant <NUM> was injected blindly (from random positions) with fat. Upon removal, it was shown that the three-dimensional scaffolding structure <NUM> of the implant <NUM> was filled with fat, and that the fat was distributed homogeneously despite the blind (random) injections.

<FIG> and <FIG> show respectively images of the implant <NUM> after the blind injections. <FIG> shows that fat is equally distributed in the implant <NUM>. The white colour represents fat and the black colour represents air. Mechanical testing (e.g. tensile, compression and shear testing) was carried out to evaluate the change in dimensions and/or mechanical properties of the scaffold before being subjected to fat injection. After tensile testing (by rubbing) for <NUM> cycles at a frequency of <NUM>, the dimensions (width, projection and height) and the softness (c-value) and the strength of the scaffold in shear (Fmax) were still within the specifications of the implant. In other words, the tensile strength of the implant <NUM> was not damaged. Comparing the softness indicator (which is a good representation of the integrity of the scaffold) after the test to results before the test, a reduction of only roughly <NUM> % was detected. Thus, although the scaffolds had a reasonable and expected loss in mechanical properties, the integrity of the scaffold remained unaffected.

<FIG> shows a flow chart of a method <NUM> for forming an implant that was described previously.

The method <NUM> comprises forming <NUM> a plurality of strands to form a three-dimensional structure, The plurality of strands are formed from a material having an a yield strength (σyield) and elastic modulus (E). The three-dimensional structure comprises a plurality of hollow channels. Each hollow channel comprises a plurality of sidewalls. A sidewall comprises a plurality of gaps and a plurality of consecutive strand segments of the plurality of strands. The plurality of strand segments and the plurality of gaps are arranged alternatingly so that a gap is formed between adjacent strand segments of the sidewall, wherein the gap comprises a gap length (gl) and a resting gap height (gh). The plurality of gaps are reversibly expandable gaps. The adjacent strand segments of a reversibly expandable gap comprise a deflection capability (δ) in response to an object being received by the gap so that an increased gap height is attained between the adjacent strand segments. The gap returns towards the resting gap height in response to the object being removed from the gap. A radius (R) of the plurality of strands and respective gap lengths (gl) of the plurality of gaps are based on the yield strength and the elastic modulus of the material.

Forming <NUM> the plurality of strands may include sequentially printing a plurality of layers, wherein a layer comprises a lattice arrangement of two-dimensional unit cells. The plurality of layers may be arranged such that aligned unit cells of consecutive layers of the plurality of layers form a hollow channel of the plurality of channels. The implant may be formed by sequentially forming (or e.g. <NUM>-D printing by fused deposition modelling) layers to form the three-dimensionally (3D) printed scaffold structure. The printing may be carried out, layer by layer in a print direction (e.g. in the z-direction), so that a sequential arrangement of successive layers are formed in the print direction. The sequential arrangement (by printing) of layers on top of each other may lead to the forming of the three-dimensional structure, with the edges (or perimeter) of the plurality of layers defining the shape and/or geometry of the implant to be formed. Alternatively, the plurality of strands may be formed by any three-dimensional printing method, such as selective laser sintering (SLS). Optionally, the three-dimensional structure may be formed by a printing process based on more than three dimensions of movement, e.g. a five-dimensional (5D) printing process, or a six-dimensional (6D) printing process.

The method <NUM> may optionally further include determining <NUM> at least one of the following parameters (e.g. before forming <NUM> the plurality of strands). The parameters to be determined may be a number of hollow channels of the three-dimensional structure to be formed, a number of layers of the three-dimensional structure to be formed, and dimensions of unit cells to be formed. Additionally, the parameters to be determined may be a gap length, gl, between adjacent strands within a layer, and a gap height, gh, of the gaps between adjacent strands within a sidewall of a channel. Additionally, the parameters to be determined may include a diameter, d, of the plurality of strands to be formed.

Determining <NUM> the parameters may include determining a deflection capability (δ) of a reversibly expandable gap based on an object to be received by the reversibly expandable gap. Determining <NUM> the parameters may further include determining material properties of the plurality of strands to be formed, wherein the material properties comprises the yield strength (σyield) and a young's modulus (E) of the material. Determining <NUM> the parameters may further include determining a radius (R) and gap length (gl) for respective strand segments of the plurality of strand segments to be formed. Determining <NUM> the parameters may further include determining a number of hollow channels of the three-dimensional structure to be formed, a number of layers of the three-dimensional structure to be formed and/or dimensions of the unit cells.

The plurality of strands may be formed after determining the parameters, such that a three-dimensional structure comprising the reversibly expandable gaps is formed. For example, the parameters may be determined, such that <MAT>. The three-dimensional structure formed may include at least one of the following parameters: the determined number of hollow channels, the determined number of layers, the determined dimensions of the unit cells, the determined gap length, gl, between adjacent strands within a layer, the determined gap height, gh, of the gaps between adjacent strands within a sidewall of a channel, the determined diameter of the plurality of strands. The three-dimensional structure formed by the method <NUM> may be three-dimensional structure of any of implants <NUM>, <NUM>, <NUM> described in connection with <FIG>.

<FIG> shows examples of implants 700A to 700F including channels with oscillating (e.g. undulating, or e.g. zig-zag, or sinusoidal) sidewalls. The implants 700A to 700F may include one or more or all of the features already described in connection with <FIG>. For example, the implants 700A to 700F may include the reversibly expandable gaps described in connection with the implants of <FIG>.

<FIG> shows a three-dimensional soft-tissue implant 700A for insertion into a patient. The implant 700A comprises a plurality of strands <NUM> forming a three-dimensional structure. The three-dimensional structure comprises a plurality of hollow channels <NUM>. Each hollow channel <NUM> comprises a plurality of intersecting sidewalls <NUM>. Each sidewall <NUM> comprises a plurality of strand segments <NUM> and a plurality of gaps <NUM> arranged alternatingly. At least one sidewall <NUM> of the hollow channel <NUM> is an undulating (e.g. oscillating, zig-zag and/or sinusoidal sidewall). Optionally, each hollow channel <NUM> may include a first undulating sidewall <NUM> and a second undulating sidewall <NUM> facing opposite to the first undulating sidewall <NUM>.

A hollow channel <NUM> with at least one undulating sidewall may be referred to as an undulating (e.g. zig-zag and/or sinusoidal) channel. A (or each) zig-zag (or sinusoidal) channel <NUM> may be a channel in which at least two opposite sidewalls of a channel are arranged with respect to each other so that the channel zig-zags between a first end <NUM> (proximal end) of the channel towards (or to) a second end <NUM> (distal end) of the channel <NUM>. For example, a zig-zag channel <NUM> may have a first zig-zag sidewall <NUM> and a second zig-zag sidewall <NUM> opposite the first zig-zag sidewall. Each zig-zag sidewall <NUM> of a zig-zag channel may comprise a plurality of strands <NUM> arranged sequentially in the z-direction. The plurality of strands <NUM> may be substantially parallel to each other, and perpendicular to the z-direction. The sequentially arranged strands <NUM> of the zig-zag sidewall <NUM> may be arranged to have a lateral offset with respect to each other, and so as to create the pattern of peaks <NUM> and troughs <NUM> along the sidewall <NUM>. The plurality of strand segments of the undulating sidewall belong to different layers of the implant. Adjacent strand segments of the undulating sidewall are separated by a gap (e.g. a reversibly expandable gap described in any of <FIG>), and have a lateral offset with respect to each other to create a pattern of a plurality of peaks and a plurality of troughs of the undulating sidewall.

Each hollow channel is formed by at least three sidewalls contiguous with each other. The peaks and troughs of the undulating sidewall are formed by the lateral offset between adjacent strand segments of the plurality of strand segments of the sidewalls. The peaks and troughs are arranged alternatingly between a first distal end of the channel and a second distal end of the channel.

An undulating portion (e.g. a zig-zag or sinusoidal portion) may be understood to be a portion that has a plurality of peaks (maximums) <NUM> and troughs (minimums) <NUM> arranged alternatingly from the first end <NUM> of the channel <NUM> to the second end <NUM> of the channel <NUM> (and/or between the first end <NUM> of the channel <NUM> to the second end <NUM> of the channel <NUM>). These peaks <NUM> and troughs <NUM> may be viewed from a vertical cross-section through the sidewall (e.g. through the z-direction). Such a vertical cross-section may be perpendicular to the strand direction and may be a cross-section through and/or parallel to the channel length.

A peak <NUM> (and/or trough <NUM>), may be formed from the strands of the zig-zag sidewall <NUM> being arranged such that an angle θ (e.g. θt or θp) forms between a first plurality of consecutive strands <NUM> and a directly adjacent second plurality of consecutive strands <NUM> of the zig-zag sidewall <NUM>. The angle θt may be the angle formed between a first plurality of consecutive strands <NUM> and a directly adjacent second plurality of consecutive strands <NUM> at the trough of the undulating portion, and the angle θp may be the angle formed between a second plurality of consecutive strands <NUM> and a directly adjacent (third) second plurality of consecutive strands at the peak of the undulating portion. An undulation portion may be a portion wherein θt and/or θp is less than <NUM> °. For contrast, a straight sidewall may be one in which θ is <NUM> ° along the entire channel length.

An undulating portion of the channel <NUM> may include at least one θt and/or θp angle that is less than <NUM> °. Optionally, the undulating portion of the zig-zag channel <NUM> may include between <NUM> and <NUM>, (or e.g. between <NUM> and <NUM>, or e.g. between <NUM> and <NUM>) peaks and troughs.

<FIG> shows an example of an implant 700A. <FIG> includes a three-dimensional perspective cross-section (top image) and a two-dimensional cross-section (bottom image) of the implant 700A. The implant 700A includes at least one undulating sidewall portion, wherein the undulating portion is a zig-zag portion.

In the example of <FIG>, the geometry of the first zig-zag sidewall portion <NUM> and the second zig-zag sidewall portion <NUM> may be dependent (or e.g. identical, or e.g. similar to each other) on each other, ignoring manufacturing differences. The use of the term "similar" may be understood to mean that the first zig-zag sidewall portion <NUM> and the second zig-zag sidewall portion <NUM> (and/or the zig-zag longitudinal axis 742A) may have one or more or all of the same features as each other, and/or that the first zig-zag sidewall and the second zig-zag sidewall may have identical or similar geometries or features over more than <NUM> % (or e.g. more than <NUM> %, or e.g. more than <NUM> %, or e.g. <NUM> %) of a channel length at least one of the first zig-zag sidewall <NUM> and the second zig-zag sidewall <NUM>. One such feature may be the number of peaks <NUM> and troughs <NUM> along the channel length. Another such feature may be the peak-to-trough height, which may be a vertical height between a peak and a directly adjacent trough. Another such feature may be the peak-to-peak width between directly consecutive peaks. Another such feature may be the trough-to-trough width between directly consecutive troughs.

For example, the first zig-zag sidewall <NUM> and the opposite second zig-zag sidewall <NUM> may have similar pattern of peaks <NUM> and troughs <NUM>. For example, the arrangement of θt and θp of the first sidewall portion <NUM> may be identical to the arrangement of θt and θp of the second sidewall portion <NUM>. Additionally or optionally, the peaks <NUM> and troughs <NUM> of the first zig-zag sidewall portion <NUM> and of the second zig-zag sidewall portion <NUM> may be arranged with respect to each other so that a (minimal or smallest) diameter between the first zig-zag sidewall portion <NUM> and the second zig-zag sidewall portion <NUM> along the length of the channel is constant. For example, the (minimal or smallest) diameters between the first zig-zag sidewall and the second zig-zag sidewall along the channel length may have a deviation of less than <NUM> %. Furthermore, the zig-zag longitudinal axis 742A may have a similar (or same) geometry as at least one of the first zig-zag sidewall <NUM> and the second zig-zag sidewall <NUM> (e.g. both sidewalls).

The first zig-zag sidewall portion <NUM> and the second zig-zag sidewall portion <NUM> may be similar (or identical) along at least <NUM> % (or e.g. at least <NUM> %, or e.g. at least <NUM> %, or e.g. <NUM> %) of a channel length at least one of the first zig-zag sidewall portion <NUM> and the second zigzag sidewall portion <NUM>. For example, the relative lateral offsets (x-direction) between consecutive strands of the first zig-zag sidewall <NUM> may be the same as the relative lateral offsets (x-direction) between consecutive strands of the second zig-zag sidewall <NUM>, ignoring differences due to manufacturing along the at least <NUM> % of the channel length of at least one of the first zig-zag sidewall portion and the second zig-zag sidewall portion.

A longitudinal axis may include, or may be defined by a plurality of mid-points along the channel length of a channel <NUM>. The plurality of mid-points may be the middle points of the (minimal or smallest) diameter, dmin, between the first sidewall and the second sidewall along the channel length. The peaks <NUM> and troughs <NUM> of the first zig-zag sidewall and of the second zig-zag sidewall may be arranged with respect to each other so that the zig-zag longitudinal axis 742A extends between the first end of the channel and the second end of the channel. The zig-zag longitudinal line 742A may have a similar pattern as the first zig-zag sidewall and the second zig-zag sidewall.

<FIG> shows an example of a further implant 700B. <FIG> includes a three-dimensional perspective cross-section (top image) and a two-dimensional cross-section (bottom image) of the implant 700B. Implant 700B may be similar to implant 700A and include one or more or all of the features of implant 700A. However, in the case of implant 700B, the second sidewall portion <NUM> may be a mirror-image of the first second sidewall portion <NUM> about the longitudinal axis 742B.

<FIG> shows an example of a further implant 700C. <FIG> includes a three-dimensional perspective cross-section (top image) and a two-dimensional cross-section (bottom image) of the implant 700C. Implant 700C may be similar to implant 700A and include one or more or all of the features of implant 700A. However, in the case of implant 700C, the undulating portions of the channel <NUM> are sinusoidal instead of zig-zag.

In a sinusoidal sidewall portion, a tangential line along the first plurality of consecutive strands <NUM> may be a varying tangential line (e.g. changing gradually, e.g. decreasing gradually) and a tangential line along the second plurality of consecutive strands <NUM> may also be varying tangential line (e.g. changing gradually, e.g. increasing gradually). In a zig-zag sidewall portion, a tangential line along the first plurality of consecutive strands <NUM> may be a constant tangential line (e.g. fixed tangential value, e.g. positive tangent) and a tangential line along the second plurality of consecutive strands <NUM> may also be constant tangential line (e.g. fixed tangential value, e.g. negative tangent).

<FIG> shows an example of a further implant 700D. <FIG> includes a three-dimensional perspective cross-section (top image) and a two-dimensional cross-section (bottom image) of the implant 700D. Implant 700D may be similar to implant 700C and include one or more or all of the features of implant 700C. However, in the case of implant 700D, the second sidewall portion <NUM> may be a mirror-image of the first second sidewall portion <NUM> about the longitudinal axis 742D.

<FIG> shows an example of a further implant 700E. <FIG> includes a three-dimensional perspective cross-section (top image) and a two-dimensional cross-section (bottom image) of the implant 700E. Implant 700E may be similar to the implants 700A to 700D and may include one or more or all of the features of the implants.

As shown in the case of implant 700E, the undulating portion may include a zig-zag portion, wherein the angles θ (e.g. θt or θp) of the undulating portion may be different (or vary) from each other within the undulating portion of a sidewall <NUM>. Varying the angle θ may change the softness of the implant. For example, portions of the implant with smaller θ may be softer than portions of the implant with larger θ. Additionally or optionally, features such as the peak-to-trough height, hpt, peak-to-peak width, wpp, and/or trough-to-trough width, wtt, may vary (differ from each other) within the undulating portion of the sidewall <NUM>.

It may be understood that the features of <FIG> may be combined with each other to form an implant having the desired softness and elasticity.

An (or each) undulating sidewall may include at least one of a zig-zag portion and a sinusoidal portion. Optionally, the said zig-zag (or sinusoidal) portion may extend over (or may include) the entire length of the channel <NUM>. Alternatively, the said zig-zag (or sinusoidal) portion may extend over (or may include) a selected portion (e.g. proportion, or fraction, or segment) of the entire length of the channel <NUM>. In some examples, one or more or all of these parameters (angles θt, θp, hpt, wpp, wtt) may be constant (e.g. the same) throughout (or within) the entire undulating portion. In other examples, these parameters may vary throughout (or within) the entire undulating portion. In some examples, the undulating portion may include the entirety (e.g. the whole) length of the sidewall <NUM>. In some examples, the undulating portion may include between <NUM> % and <NUM> % (or e.g. between <NUM> % and <NUM> %, or e.g. between <NUM> % and <NUM> %) of the entire sidewall <NUM>. For example, the sidewall may include an undulating portion and a straight portion. In some examples, the sidewall <NUM> may include any number and/or combination of zig-zag portions, sinusoidal portions and straight portions.

The sidewalls <NUM> of a channel <NUM> (e.g. the sidewalls enclosing a channel <NUM>) may be similar (same or e.g. identical) to each other. Alternatively, or optionally, they may be dependent on each other (e.g. being a mirror-image of each other). Alternatively, or optionally, they may be different from each other. In some examples, all the sidewalls of an implant may be sinusoidal sidewalls. In other examples, all the sidewalls of the implant may be zig-zag sidewalls. In some examples, the sidewalls of the implant may be a mixture of zig-zag and sinusoidal sidewalls.

<FIG> shows an example of a further implant 700F. <FIG> includes a three-dimensional perspective cross-section (top image) and a two-dimensional cross-section (bottom image) of the implant 700F. Implant 700F may be similar to the implants 700A to 700E and may include one or more or all of the features of the implants.

As shown in the <FIG>, the implant 700F may include tilted, zig-zag (sinusoidal) channels, whereas <FIG> showed channels extending parallel to the z-direction.

In tilted channels, an acute tilt angle, k, between a longitudinal axis 742E and a reference axis (e.g. an x-axis or y-axis) representing the first outer surface region may be less than <NUM> degrees, or for example, less than <NUM> degrees.

<FIG> shows an example of a further implant <NUM>. <FIG> includes a three-dimensional perspective cross-section (top image) and a two-dimensional cross-section (bottom image) of the implant <NUM>. Implant <NUM> may be similar to the implants 700A to 700F and may include one or more or all of the features of the implants.

<FIG> shows a the sidewalls having a fractal zig-zag portion (e.g. zig-zagging portions within a zig-zagging portion). In other words, first plurality of consecutive strands <NUM> instead of forming a smooth surface, may include zig-zagging portions. Additionally or optionally, the second plurality of consecutive strands <NUM>, instead of forming a smooth surface or line, may include zig-zagging portions.

Claim 1:
A three-dimensional implant (<NUM>, <NUM>, <NUM>) for tissue reconstruction or tissue augmentation for insertion into a patient, the implant comprising:
a plurality of planar layers, wherein a first group of sublayers (<NUM>) comprises a plurality of strands oriented in first direction, wherein a second group of sublayers (<NUM>) comprises a plurality of strands oriented in a second direction, the sublayers of the first group of sublayers (<NUM>) and the sublayers of the second group of sublayers (<NUM>) are arranged alternatingly in a third direction, the plurality of layers forming a three-dimensional structure comprising a plurality of hollow channels (<NUM>) extending in the third direction, wherein the implant is compressible at least along the third direction;
wherein each hollow channel (<NUM>) comprises a first sidewall (104A) extending in the third direction and comprises a plurality of strand segments (105A) oriented in a first direction and a plurality of gaps (106A) arranged alternatingly, and a second sidewall (104B) extending in the third direction and comprising a plurality of strand segments (105B) oriented in the second direction and a plurality of gaps (106B) arranged alternatingly, wherein at least one of the first sidewall (104A) and the second sidewall (104B) of the hollow channel is an undulating sidewall,
wherein the plurality of strand segments (105A, 105B) of the undulating sidewall (104A, 104B) belong to different layers of the implant, wherein adjacent strand segments (105A, 105B) of the undulating sidewall (104A, 104B) are separated by a gap (<NUM>), wherein the adjacent strand segments (105A, 105B) have a lateral offset with respect to each other to create a pattern of a plurality of peaks (<NUM>) and a plurality of troughs (<NUM>) of the undulating sidewall (104A, 104B).