MEDICAL IMPLANT, METHOD FOR MANUFACTURING A MEDICAL IMPLANT, MEDICAL PRODUCT, ALIGNMENT TOOL, METHOD FOR CUSTOMIZING A MEDICAL IMPLANT, AND FELTING INSTRUMENT

Abstract

The invention relates to a medical implant (100) extending along a plane (P) perpendicular to a first axis (A1), wherein the medical implant (100) comprises a felt material (F) comprising a plurality of fibers (101), wherein a density of said fibers (101) varies along said plane (P), and/or a percentage of said fibers (101) aligned in a circumferential direction (C) in respect of said first axis (A1) differs along said plane (P), a method for manufacturing the medical implant (100) by felting and a method for customizing the medical implant (100).

Furthermore, the invention relates to s medical product (300) comprising the medical implant (100) and a transparent packaging (310) comprising printed markings (320), and to a felting instrument (200) comprising a felting needle (210) comprising at least one barb (211).

Claims

1. A medical implant (100), particularly for meniscus repair or replacement, wherein the medical implant (100) extends along a plane (P) perpendicular to a first axis (A1), and wherein the medical implant (100) comprises a felt material (F) comprising a plurality of fibers (101), characterized in that a density of said fibers (101) varies along said plane (P), particularly resulting in a varying compressive strength along said first axis (A1), and/or a percentage of said fibers (101) aligned in a circumferential direction (C) in respect of said first axis (A1) differs along said plane (P), particularly resulting in a varying tensile strength of the medical implant (100) along said plane (P).

2. The medical implant (100) according to claim 1, characterized in that said medical implant (100) comprises an outside surface (102), wherein said density of said fibers (101) increases in a radial direction (R) in respect of the first axis (A1) towards the outside surface (102), particularly such that said compressive strength increases in the radial direction (R) towards the outside surface (102), and/or said percentage of said fibers (101) aligned in said circumferential direction (C) increases in the radial direction (R) towards the outside surface (102), particularly such that said tensile strength of the medical implant (100) increases in said radial direction (R) towards said outside surface (102).

3. The medical implant (100) according to claim 1, characterized in that said medical implant comprises a plurality of zones (110, 111, 112, 113), wherein said density of said fibers (101) and/or said percentage of said fibers (101) aligned in the circumferential direction (C) varies between the zones (110, 111, 112, 113), wherein particularly said zones (110, 111, 112, 113) are arranged along said radial direction (R).

4. The medical implant (100) according to claim 1, characterized in that said medical implant extends from a first end (121) via a central section (122) towards a second end (123) along a curved line (CL) extending in the circumferential direction (C), wherein the medical implant (100) comprises a central recess (130), around which the curved line (CL) extends.

5. The medical implant (100) according to claim 1, characterized in that said medical implant is formed from a plurality of layers (140, 141, 142, 143, 144) of said felt material (F), wherein the layers (140, 141, 142, 143, 144) are stacked in a direction parallel to the first axis (A1), and wherein said layers (140, 141, 142, 143, 144) are connected by felting.

6. The medical implant (100) according to claim 4, wherein said medical implant is formed from a plurality of layers (140, 141, 142, 143, 144) of said felt material (F), wherein the layers (140, 141, 142, 143, 144) are stacked in a direction parallel to the first axis (A1), and wherein said layers (140, 141, 142, 143, 144) are connected by felting, and is characterized in that said layers (140, 141, 142, 142, 144) comprise a bottom layer (140) and a top layer (141), wherein an arc length of the bottom layer extending along the curved line (CL) is greater than an arc length of the top layer (141) extending along the curved line (CL), such that a thickness of the medical implant (100) measured parallel to the first axis (A1) increases from the first end (121) towards the central section (122) and/or from the second end (123) towards the central section (122), wherein particularly said layers (140, 141, 142, 144) comprise at least one intermediate layer (142, 143) between the bottom layer (140) and the top layer (141), wherein an arc length of the at least one intermediate layer (142, 143) is between the arc length of the bottom layer (140) and the arc length of the top layer (141), wherein more particularly the medical implant (100) further comprises a first cover layer (144) covering the bottom layer (140), the intermediate layers (142, 143) and the top layer (141) on a top surface (103), particularly from the first end (121) towards the second end (122) and/or the medical implant (100) further comprises a second cover layer (145) covering said bottom layer (140), said intermediate layers (142, 143) and said top layer (141) on a rim surface (104).

7. The medical implant (100) according to claim 6, characterized in that said medical implant (100) comprises a strip (150) comprising said felt material (F), wherein said strip (150) is arranged in said circumferential direction (C) in respect of the first axis (A1) along an outside surface (102) of the medical implant (100) between the bottom layer (140) and the top layer (141), wherein particularly said strip (150) extends along said curved line (CL), wherein more particularly said strip (150) has an arc length along the curved line (CL) which is shorter than the arc length of the bottom layer (140) and shorter than the arc length of the top layer (141).

8. The medical implant (100) according to claim 4, characterized in that said medical implant (100) comprises a replacement member (160) configured to replace a part of a soft biological tissue (ST), particularly a meniscus, and a supporting body (170) connected to the replacement member (160), wherein the supporting body (170) extends from the first end (121) via the central section (122) to the second end (123) along the curved line (CL) in the circumferential direction (C), and wherein the replacement member (160) is arranged on a bottom surface (171) of the supporting body (170), wherein the replacement member (160) covers a partial segment of said bottom surface (171), wherein particularly said replacement member (160) has a thickness measured parallel to the first axis (A1) which is greater than a thickness of the supporting body (170) measured parallel to the first axis (A1).

9. A method of manufacturing a medical implant (100), according to claim 1, wherein at least one sheet (10) comprising a felt material (F) is provided, the sheet (10) extending along a plane (P) perpendicular to a first axis (A1), wherein the felt material (F) comprises a plurality of fibers (101), and wherein a felting needle (210) comprising at least one barb (211) is repeatedly advanced through the sheet (10) at specified locations to increase the density of the fibers (101), particularly such that the compressive strength of the sheet (10) measured parallel to the first axis (A1) is increased at the specified locations and/or to increase the percentage of fibers (101) aligned in a circumferential direction (C) in respect of the first axis (A1), particularly such that the tensile strength of the sheet (10) measured parallel to the plane (P) is increased at the specified locations.

10. A medical product (300) comprising a medical implant (100) according to claim 1, and a transparent packaging (310), wherein the packaging (310) comprises printed markings (320) comprising an outline marking (321) of the shape of the medical implant (100), a radial scale marking (322) and a circumferential scale marking (323), wherein the medical implant (100) is arranged in the packaging (310), such that the outline marking (321) is aligned with the medical implant (100).

11. An alignment tool (400) comprising a working surface (401) configured to receive the medical product according to claim 10, and a holder (402) configured to be placed on the working surface (401), wherein the holder (402) comprises a cutout (403) having a size and shape of the medical implant (100), particularly such that the outline marking (321) and/or the medical implant (100) can be aligned with the cutout (403), wherein particularly the working surface (401) is covered by a spongy material (401a).

12. A method for customizing a medical implant, according to claim 1, wherein a medical product (100) is provided, and wherein a desired shape of the medical implant (100) is marked on the transparent packaging (310) of the medical product (300) using the radial scale marking (322) and the circumferential scale marking (323, and wherein a piece (11) is cut out of the medical implant (100) and the packaging (310) using the marked desired shape, particularly wherein a supporting body (170) comprising a felt material (F) is arranged on the working surface (401) of the alignment tool (400), and wherein the medical product (300) comprising a hole (340) generated by cutting out the piece (11) of the medical implant (100) and the packaging (310) are arranged on the supporting body (170), and wherein the piece (11) cut out of the medical implant (100) is arranged in the hole (340), and wherein a felting needle (210) comprising at least one barb (211) is repeatedly advanced through the piece (11) and the supporting body (170), thereby connecting the piece (11) to the supporting body (170).

13. A felting instrument (200) comprising a felting needle (210) comprising at least one barb (211), wherein the felting instrument (200) comprises a drive (220) configured to move the felting needle (210) back and forth along a longitudinal axis (L).

14. The felting instrument (200) according to claim 13, characterized in that the felting needle (210) is curved.

15. The felting instrument (200) according to claim 13, characterized in that the felting instrument (200) comprises a supporting member (230) configured to hold a medical implant (100) comprising a felt material (F) comprising a plurality of fibers (101) in place on a biological soft tissue (ST), particularly a meniscus, such that the felting needle (210) of the felting instrument (200) can be advanced through the medical implant (100) and the soft tissue (ST) to connect the medical implant (100) to the biological soft tissue (ST), particularly wherein the supporting member (230) comprises a lower member (231) configured to be arranged below the soft biological tissue (ST) and/or through the soft biological tissue (ST), and wherein the supporting member (230) comprises an upper member (234) configured to be arranged on the medical implant (100), particularly to apply pressure on the medical implant (100), more particularly wherein said lower member (231) comprises an end section (235) that is flippable to connect the end section (235) to the upper member (234).

Description

[0093] The invention is further illustrated by the following examples and figures, from which further embodiments and advantages can be drawn. These examples are meant to illustrate the invention but not to limit its scope.

[0094] FIG. 1 depicts a sheet from a felt material and a felting instrument comprising a felting needle for changing the density and alignment of fibers in the felt material;

[0095] FIG. 2 shows embodiments of a medical implant according to the invention for meniscus repair or replacement;

[0096] FIG. 3 shows the fiber alignment in different zones of a medical implant according to the invention;

[0097] FIG. 4 shows the assembly of a medical implant according to an embodiment of the invention from layers comprising a felt material;

[0098] FIG. 5 shows the assembly of a medical implant according to a further embodiment of the invention from layers comprising a felt material;

[0099] FIG. 6 shows medical implants according to the invention comprising a replacement member and a supporting body;

[0100] FIG. 7 shows a medical product according to the invention comprising a medical implant according to the invention arranged in a transparent packaging comprising markings;

[0101] FIG. 8 illustrates a method for obtaining a medical implant of a desired shape from the medical product shown in FIG. 7;

[0102] FIG. 9 shows an alignment tool according to the invention;

[0103] FIG. 10-11 show a method for obtaining a medical implant according to the invention comprising a replacement part and a supporting body using the medical product shown in FIGS. 7 and 8 and the alignment tool shown in FIG. 9;

[0104] FIG. 12 depicts a method for connecting fibers of a felt material to a soft tissue using a felting instrument according to the invention;

[0105] FIG. 13 shows an embodiment of the felting instrument according to the invention used for connecting a medical implant according to the invention to soft tissue;

[0106] FIG. 14 shows a further embodiment of the felting instrument according to the invention used for connecting a medical implant according to the invention to soft tissue;

[0107] FIG. 15 shows an embodiment of the felting instrument according to the invention.

[0108] FIG. 1A schematically depicts a sheet 10 from a felt material F comprising a plurality of randomly arranged fibers 101.

[0109] As part of a manufacturing method for a medical implant 100 according to the invention, a felting needle 210 of a felting instrument 200, the felting needle 210 comprising a plurality of barbs 211, may be advanced with its tip 212 into the sheet 10 and repeatedly moved back and forth along a longitudinal axis L, which in this case extends along the felting needle 210 (FIG. 1B, details of the felting instrument 200 shown in the inset of FIG. 1B).

[0110] Thereby, the barbs 211 of the felting needle 210 pull and push fibers 101 of the felt material F, which results in a changed density of the fibers 101 and in an altered alignment of the fibers 101 (FIG. 1C). In the depicted example, the density of the sheet 10 is increased at the position where the felting needle 210 has been introduced, resulting in a denser packing of the fibers 101 and therefore a decreased thickness along the first axis A1.

[0111] FIG. 2A-D show embodiments of a medical implant 100 comprising a felt material F for meniscus replacement according to the invention. FIGS. 2A and 2B show medical implants 100 designed to replace the lateral meniscus, and FIGS. 2C and 2D depict medical implants 100 configured to replace the medial meniscus. Therein, FIGS. 2A and 2C are side views of the respective medical implant 100, and FIGS. 2B and 2D are sectional views along a plane P perpendicular to the first axis A1 indicated in FIGS. 2A and 2C. FIG. 2E shows the location of the medical implant 100 on a tibia bone B when replacing the lateral meniscus, and FIG. 2F shows the location of the medical implant 100 on a tibia bone when replacing the medial meniscus.

[0112] As best seen in FIGS. 2B and 2D, the medical implant 100 extends along the plane P from a first end 121 via a central section 122 to a second end 123 along a curved line CL extended in a circumferential direction C in respect of the first axis A1. The medical implant 100 has a central recess 130 resulting in a C-shape or crescent moon shape which resembles the natural meniscus. The shape and size of the medical implant 100 differs slightly between the lateral meniscus implant (FIG. 2B) and the medial meniscus implant (FIG. 2D). E.g., in the medial meniscus implant, the central recess 130 is larger than in the lateral meniscus implant.

[0113] In the cross-sectional view of FIGS. 2B and 2D, three different zones 111, 112, 113 differing in their mechanical properties are visible. The zones 111, 112, 113 each extend in the plane P between the first end 121 and the second end 123 along the curved line CL. The first zone 111 is arranged along the edge of the central recess 130 on the inside of the medical implant 100. The second zone 112 is arranged outside of the first zone 111 in a radial direction R, and the third zone 113 is arranged outside of the second zone 112 along an outside surface 102 of the medical implant 100. A fourth zone 114 (depicted by the thick line marking the outline of the medical implant 100 in FIGS. 2A and 2C) is arranged around the entire outside surface 102.

[0114] In particular, the density of the fibers 101 of the felt material F in the medical implant 100 differ between the zones 111, 112, 113, 114 resulting in a varying compressive strength along the first axis A1 in the different zones 111, 112, 113, 114. More particularly, the density of the fibers 101 may increase from the first zone 111 to the second zone 112, and from the second zone 112 to the third zone 113. The varying compressive strength in the plane P particularly resembles the mechanical properties of the natural meniscus.

[0115] Furthermore, as illustrated in FIG. 3, the percentage of the fibers 101 aligned in the circumferential direction (see FIGS. 2B and 2D) may differ between the zones 111, 112, 113, 114. FIG. 3 shows the lateral meniscus implant 100 (left) and the medial meniscus implant 100 (right) according to the invention comprising the zones shown in FIG. 2 and described above.

[0116] Two spots per first, second and third zone 111, 112, 113 and one spot of the fourth zone 114 are enlarged and the corresponding fiber alignment is illustrated in the insets (wherein (a) marks the first zone 111, (b) marks the second zone 112, (c) marks the third zone 113, an (d) marks the fourth zone 114).

[0117] As shown in FIG. 3, the percentage of fibers 101 aligned in the circumferential direction increases from the first zone 111 towards the second zone 112, and from the second zone 112 towards the third zone 113, and then decreases from the third zone 113 to the fourth zone 114. In the depicted example, the distribution of the fiber 101 directions appears almost random in the first zone 111 and the fourth zone 114, whereas a higher percentage of fibers 101 are oriented parallel to each other (and aligned in the circumferential direction) in the second zone 112, and almost all fibers 101 are parallel (and aligned in the circumferential direction) in the third zone 113.

[0118] According to certain embodiments, the percentage of fibers 101 aligned in the circumferential direction is less than 60% in the first zone 111, 30% to 80% in the second zone 112, more than 50% in the third zone 113, and less than 60% in the fourth zone 114.

[0119] The depicted alignment of fibers 101 in the circumferential direction C results in varying tensile strength of the medical implant in the different zones 111, 112, 113, 114, similar to the natural mechanical properties of the meniscus.

[0120] According to certain embodiments, the tensile strength of the medical implant in the plane P, particularly in the circumferential direction C, is in the range of 0,050 MPa to 90 MPa in the first zone 111, in the range of 0,750 MPa to 140 MPa in the second zone 112, in the range of 0,100 MPa to 176 MPa in the third zone 113, and in the range of 0,050 MPa to 16 MPa in the fourth zone 114.

[0121] FIGS. 4 and 5 depict two different methods of assembling a medical implant 100 from a felt material F for meniscus replacement according to the invention.

[0122] According to a first embodiment, as shown in FIG. 4, layers 140, 141, 142, 143 from a felt material F are stacked along the first axis A1 and connected to each other by advancing a felting needle 210 of a felting instrument 200 (see FIG. 1B) repeatedly through the stacked layers 140, 141, 142, 143 to felt the layers 140, 141, 142, 143 together. Therein, a bottom layer 140 is provided, and a first intermediate layer 142, a second intermediate layer 143 and a top layer 141 are subsequently stacked on top of the bottom layer 140 and then connected (either in separate steps to connect adjacent layers or in a single step to connect all layers simultaneously) by felting. The first intermediate layer 142 has a shorter arc length along the curved line CL depicted in FIG. 2 than the bottom layer 140, the second intermediate layer 143 has a shorter arc length along the curved line CL shown in FIG. 2, and the second intermediate layer 143 has a shorter arc length along the curved line CL than the top layer 141, resulting in a slope from the first end 121 to the central section 122 and from the second end 123 to the central section 122 (see reference signs indicated in FIG. 2). This results in a stepwise increase of thickness along the first axis A1 from the first end 121 to the central section 122 and from the second end 123 to the central section 122.

[0123] After assembling the layers 140, 141, 142, 143, a first cover layer 144 is arranged on a top surface 103 of the medical implant 100 and connected by felting, resulting in the arrangement shown in FIG. 4E. The first cover layer 144 equilibrates the steps formed at the interfaces between the adjacent layers 140, 141, 142, 143 and leads to a gradual thickness increase from the first and second end 121, 123 to the central section 122.

[0124] In addition, a second cover layer 145 (shown individually in FIG. 4A) is arranged on a rim surface 104 of the stacked layers 140, 141, 142, 143 (see FIG. 4B) and connected by felting (see FIG. 4C).

[0125] The first cover layer 144 and the second cover layer 145 may together constitute the fourth zone 114 as shown in FIGS. 2 and 3.

[0126] The medical implant 100 depicted in FIG. 4 may be used e.g. for complete meniscus replacement after surgical removal of the natural lateral or medial meniscus.

[0127] FIG. 5 shows an assembly method of a further embodiment of the medical implant 100 according to the invention.

[0128] As shown in FIG. 5B, a strip 150 comprising a felt material F is first arranged along the outside edge of a bottom layer 140 comprising a felt material F. The strip 150 is then connected to the bottom layer 140 by felting. Subsequently, a top layer 141 from a felt material is arranged on top of the bottom layer 140 and the strip 150, and the components are connected by felting. Subsequently, a second cover layer is arranged on a rim surface 104 of the stacked bottom layer 140, strip 150 and top layer 141 and connected by felting.

[0129] Thereby, a gradual thickness increase from the first and second end 121, 123 to the central section 122 (see FIG. 2) is achieved.

[0130] The medical implant 100 depicted in FIG. 5 may be used e.g. for complete meniscus replacement after surgical removal of the natural lateral or medial meniscus.

[0131] In FIG. 6, a single piece medical implant 100 for meniscus replacement (FIG. 6A), and a two-piece medical implant 100 for partial meniscus replacement (resulting in meniscus repair, FIGS. 6B and 6C) is shown. The medical implant 100 for partial meniscus replacement (FIGS. 6B and 6C) comprises a replacement member 160 and a supporting body 170, both comprising a felt material F, wherein the replacement member 160 is connected to a bottom surface 171 of the supporting body 170 by felting. The replacement member 160 (shown individually in FIG. 6D) is configured to be inserted in a gap of the natural meniscus obtained by surgical removal of a part of the cartilage material of the natural meniscus to fill the gap. The supporting body 170 is configured to cover the remaining natural meniscus to mechanically support the replacement member 160. In particular, the supporting body 170 may be felted to the natural meniscus by a surgical felting instrument 200.

[0132] FIG. 7 shows a medical product 300 comprising a medical implant 100 for meniscus repair or replacement arranged in a transparent packaging 310. The transparent packaging 310 comprises printed markings 320, namely an outline marking 321, a radial scale marking 322 and a circumferential scale marking 323.

[0133] The outline marking 321 resembles the size and shape of the medical implant 100 in the packaging 310 and the medical implant 100 is arranged in the packaging 310, such that it is aligned with the outline marking 321.

[0134] The radial scale markings 322 consist of lines (e.g. dotted lines as shown in FIG. 7, or solid lines) extending in a radial direction R in respect of the first axis A1 of the medical implant 100 (see FIG. 2), wherein the lines point to the center of the central recess 130.

[0135] The circumferential scale markings 323 consist of lines (e.g. dotted lines as shown in FIG. 7, or solid lines) oriented in the circumferential direction C in respect of the first axis A1 of the medical implant 100 (see FIG. 2) along the medical implant 100.

[0136] By the crossing lines of the radial scale markings 322 and circumferential scale markings 323, a coordinate system is defined on the surface of the medical implant 100 in the packaging 310.

[0137] Radial coordinates from 2 to 6 indicating a radial distance from the edge of the central recess 130 are indicated at the opening of the central recess 130.

[0138] In a similar manner, circumferential coordinates ranging from 0 to 27 (0 being a root at a radial edge 132 of an opening 131 of the central recess 130) are indicated along the periphery of the medical implant in both clockwise and counterclockwise directions.

[0139] The packaging 310 further comprises two through-holes 311 for aligning the medical product 300 on an alignment tool 400 (see below).

[0140] The markings 320 can be used to cut out a piece 11 of a pre-selected size and shape from the medical implant 100, using scissors 12 or alternatively a scalpel, particularly to form a custom-sized replacement part 160 of a two-part medical implant 100 as shown in FIGS. 6B and 6C.

[0141] Part of this process is illustrated in FIG. 8.

[0142] After an empty space has been created in the natural meniscus by partial meniscectomy, the position and size of the empty space is measured.

[0143] Then, as shown in FIG. 8B a first line 331 is drawn (using a pen) on the packaging 310 in the radial direction R with the help of the radial scale markings 322 and circumferential scale markings 323 according to the measured radial dimensions (depth) and start coordinate 334 in the circumferential direction C of the empty space of the natural meniscus.

[0144] Next, as shown in FIG. 8C, a second line 332 is drawn on the packaging 310 in the circumferential direction C between the start coordinate 334 and an end coordinate 335.

[0145] Finally, a radial third line 333 is drawn on the packaging from the end coordinate 335 inwards towards an edge of the central recess 130.

[0146] By cutting along the first line 331, the second line 332 and the third line 333, a piece 11 of the medical implant 100 of desired shape and size to fill the empty space in the natural meniscus can be cut out of the medical implant 100 in the medical product 300. A corresponding hole 340 is formed in the medical implant 100 and transparent packaging 310 (see FIG. 8D).

[0147] To assemble the cut-out piece 11 with a supporting body 170 to form a two-piece medical implant 100 as shown in FIGS. 6B and 6C and described above (wherein the cut-out piece 11 is the replacement member 160), an alignment tool 400 as shown in FIG. 9 can be used.

[0148] The alignment tool 400 comprises a working surface 401, wherein a partial surface of the working surface 401 having the crescent moon shape of the medical implant 100 is particularly covered with a special smooth or spongy material which facilities the use of a felting needle 210 on the working surface 401. The alignment tool 400 further comprises a holder 402 comprising a cutout 403 resembling the crescent moon shape of the medical implant 100. The part comprising the working surface 401 comprises four bores 406 with an inner thread and the holder 402 comprise corresponding through-holes 408 which can be aligned with the bores 406 when the holder 402 is placed on the working surface 401. The holder 402 can then be fixed on the working surface 401 using fixing members 405, such as screws, which are inserted into the bores 406 and through-holes 408.

[0149] Notches 407 are arranged around an edge 404 of the cutout 403 of the holder 402, the notches 407 extending in the radial direction or the circumferential direction. These notches 407 are designed to guide a scalpel during cutting the medical implant 100 into a desired shape, e.g. along the first line 331, the second line 332 and the third line 333 indicated in FIG. 8B-D, which facilitates the cutting procedure.

[0150] FIGS. 10 and 11 show a method, by which a two-part medical implant 100, such as the one shown in FIGS. 6B and 6C can be assembled from a supporting body 170 and a replacement member 160 using the previously described medical product 300 and the alignment tool 400.

[0151] First, the supporting body 170 is placed on the working surface 401 of the alignment tool 400, particularly on the spongy material 401a (FIG. 10B).

[0152] Subsequently, as shown in FIGS. 10A and 10B, after cutting out the piece 11 from the medical product as illustrated in FIG. 8 and described above, the remaining medical product 300 comprising the hole 340 and a cut 313 leading from a lower edge of the packaging 310 to the hole 340 is placed on the working surface 401, and the outline marking 321 of the packaging 310 is aligned with the supporting body 170. The packaging 310 may be aligned and held in place by two pins 408 arranged on opposite sides of the working surface 401 which insert into corresponding through-holes 311 of the packaging. In the example depicted in FIG. 10, the through-holes 311 are arranged in latches 312.

[0153] Next, as illustrated in FIG. 11A, the piece 11 constituting the replacement member 160 is placed in the hole 340, and the replacement member 160 is connected to the supporting body 170 by felting, using the felting instrument 200.

[0154] Finally, the medical product 300 comprising the hole 340 and the finished medical implant 100 for partial meniscus replacement is removed from the alignment tool 400 (FIGS. 11B and 11C).

[0155] FIG. 12 shows a method of connecting fibers 101 of a felt material F to biological soft tissue ST by a surgical felting instrument 200, which can be used to connect the medical implant 100 according to the invention to soft tissue SF, such as a lateral or medial meniscus.

[0156] As shown in FIG. 12A-C, the barbs 211 on the felting needle 210 of the felting instrument 200 pull and push fibers 101 into the soft tissue ST when the felting needle is moved back and forth along the longitudinal axis L in the soft tissue ST driven by the drive 220.

[0157] FIGS. 13 and 14 show a specific embodiment of the felting instrument 200 according to the invention as it is used to connect a medical implant 100 comprising a felt material F to biological soft tissue ST arranged on a bone B. The soft tissue ST may be e.g. a natural meniscus, and the medical implant may be a meniscus implant formed according to the present invention.

[0158] The felting instrument 200 comprises a felting needle 210 comprising at least one barb 211 and a drive 220 for moving the felting needle 210 back and forth along a longitudinal axis L.

[0159] In the depicted embodiment, the felting needle 210 is curved, such that the medical implant 100 can be conveniently connected to the soft tissue ST without touching the bone B.

[0160] In addition, as shown in FIGS. 13A and 14 A-E, the felting instrument 200 comprises a supporting member 230 comprising a lower member 231 configured to be advanced below the soft tissue ST or partially through the soft tissue ST to hold the soft tissue ST in place during felting. The supporting member 230 further comprises an upper member 234 configured to be placed on top of the medical implant 100 to apply force on the medical implant 100 and the soft tissue ST to ensure that their relative position does not change during felting. The lower member comprises a flippable end section 235 that can be flipped up towards the upper member 234 to support the medical implant 100 from the lateral side opposite the felting needle 210, and particularly form a cage-like compartment around the medical implant 100 and the soft tissue ST.

[0161] The flipping of the end section 235 is depicted in more detail in FIG. 14C-E

[0162] Alternatively, as depicted in FIG. 13B, the supporting member 230 may consist only of the upper member 234.

[0163] The lower member 231 may be formed as a needle 232 comprising a sharp tip 233, such that the lower member 231 can penetrate into and through the soft tissue ST, which improves fixation of the soft tissue ST.

[0164] FIG. 15 shows additional details of a felting instrument 200 (FIG. 15A) comprising a curved felting needle 210 comprising barbs 211 (not shown, see FIG. 12), and a supporting member 230 formed as a attachable and removable part (FIG. 15B). FIG. 15C shows the assembled felting instrument 200 including the supporting member 230.

[0165] The supporting member 230 comprises at least one lower part 231 with a flippable end section 235 and at least one upper part 234, wherein the lower part 231 and the upper part 234 are attached to a first ring 236. A connecting rod 238 connects the first ring 236 to a second ring 237 which may be attached to the felting instrument 200.

[0166] The connecting rod 238 and the rings 236, 237 are arranged such that a shaft 239, in which the felting needle 210 moves, is spaced apart from the connecting rod 238 and extends through the first ring 236 and the second ring 237. Thereby, the felting needle 210 cannot touch the supporting member 230 avoiding damage to the components of the felting instrument 200.

LIST OF REFERENCE SIGNS

[0167]

TABLE-US-00001 10 Sheet 11 Piece 12 Scissors 100 Medical implant 101 Fiber 102 Outside surface 103 Top surface 104 Rim surface 111, 112, 113, 114 Zone 121 First end 122 Central section 123 Second end 130 Central recess 131 Opening 132 Edge 140, 141, 142, 143, 144 Layer 140 Bottom layer 141 Top layer 142, 143 Intermediate layer 144 First cover layer 145 Second cover layer 150 Strip 160 Replacement member 170 Supporting body 171 Bottom surface 200 Felting instrument 210 Felting needle 211 Barb 212 Tip 220 Drive 230 Supporting member 231 Lower member 232 Needle 233 Tip 234 Upper member 235 End section 236 First ring 237 Second ring 238 Connecting part 239 Shaft 300 Medical product 310 Transparent packaging 311 Through-hole 312 Latch 313 Cut 320 Markings 321 Outline marking 322 Radial scale marking 323 Circumferential scale marking 331 First line 332 Second line 333 Third line 334 Start coordinate 335 End coordinate 340 Hole 400 Alignment tool 401 Working surface 401a Spongy material 402 Holder 403 Cutout 404 Edge 405 Fixing means 406 Bore 407 Notch 408 Through-hole A1 First axis B Bone C Circumferential direction CL Curved line F Felt material L Longitudinal axis P Plane R Radial direction ST Soft Tissue