Synthetic semiabsorbable composite yarn

• US 5,217,495 A
• Filed: 11/13/1990
• Issued: 06/08/1993
• Est. Priority Date: 05/10/1989
• Status: Expired due to Term

• Current Assignee: United States Surgical Corporation (Medtronic Plc)
• Original Assignee: United States Surgical Corporation (Medtronic Plc)
• Inventors: Kennedy, John, Muth, Ross R., Kaplan, Donald S.
• Primary Examiner(s): ISABELLA, DAVID J
• Application Number:
  US07/612,612
• Time in Patent Office: 938 Days
• Field of Search: 623/1, 623/11, 623/13, 623/66, 623/15, 623/18, 606/230, 606/228, 57/225, 57/226
• US Class Current: 623/13.18
• CPC Class Codes: A61F 2/06 Blood vessels
• CPC Class Codes: A61F 2/08 Muscles; Tendons; Ligaments sutures A61B17/04
• CPC Class Codes: A61F 2210/0004 bioabsorbable
• CPC Class Codes: A61L 27/58 Materials at least partially resorbable by the body
• CPC Class Codes: D02G 3/328 containing elastane
• CPC Class Codes: D02G 3/448 Yarns or threads for use in medical applications D02G3/449 takes precedence; surgical suture materials A61L17/00
• CPC Class Codes: D04C 1/02 made from particular materials
• CPC Class Codes: D04C 1/06 Braid or lace serving particular purposes
• CPC Class Codes: D04C 1/12 Cords, lines, or tows
• CPC Class Codes: D10B 2401/061 elastic
• CPC Class Codes: D10B 2401/12 biodegradable
• CPC Class Codes: D10B 2509/00 Medical; Hygiene
• CPC Class Codes: Y10S 623/926 Synthetic

Abstract

A semi-bioabsorbable connective tissue prosthesis, e.g., a replacement for the human anterior cruciate ligament, is provided whose stress-strain characteristics closely match those of the natural tissue.

Claims

1. A synthetic, semiabsorbable composite yarn which comprises:

a) a nonabsorbable, elastic core yarn component imparting resiliency to the composite yarn; and

b) at least one absorbable, relatively inelastic sheath yarn component imparting transverse strength to the composite yarn;

wherein said sheath yarn component is braided about said core yarn component.

2. The composite yarn of claim 1 wherein the core yarn component comprises one or multiple filaments.

3. The composite yarn of claim 2 wherein the core yarn component comprises twisted or intertwined multiple filaments.

4. The composite yarn of claim 1 wherein the sheath yarn component comprises one or multiple filaments.

5. The composite yarn of claim 4 wherein the sheath yarn component comprises twisted or intertwined multiple filaments.

6. The composite yarn of claim 1 in which the denier of an individual filament in said core yarn component and/or sheath yarn component is from about 0.2 to about 6.0.

7. The composite yarn of claim 6 in which the denier of an individual filament in said core yarn component and/or said sheath yarn component is from about 0.4 to about 3.0.

8. The composite yarn of claim 1 in which the core yarn component is manufactured from at least one polymeric material selected from the group consisting of ethylene homopolymer, propylene homopolymer, ethylene propylene copolymers, ethylene propylene terpolymers, fluorinated hydrocarbons, fluorosilicones, isobutylenes, isoprenes, polyacrylates, polybutadienes, polyurethanes, and polyetherpolyester copolymers.

9. The composite yarn of claim 8 in which the core yarn component is manufactured from a family of copolyester elastomers based on (soft) polyester segments and (hard) polyester segments.

10. The composite yarn of claim 8 in which the core yarn composite is manufactured from spandex.

11. The composite yarn of claim 1 in which the core yarn component possesses an elongation at break of at least about 30%.

12. The composite yarn of claim 11 in which the core yarn component possesses an elongation at break of at least about 40%.

13. The composite yarn of claim 12 in which the core yarn component possesses an elongation at break of at least about 50%.

14. The composite yarn of claim 1 in which the sheath yarn component is manufactured from an absorbable, relatively inelastic polymeric material derived at least in part from a monomer selected from the group consisting of glycolic acid, glycolide, lactic acid, lactide, p-dioxanone, trimethylene carbonate, e-caprolactone and hydroxycaproic acid.

15. The composite yarn of claim 14 wherein said sheath yarn component is manufactured from polymer having high lactide or glycolide content.

16. The composite yarn of claim 15 wherein said polymer comprises about 70 to about 90 mole percent lactide with the balance being glycolide.

17. The composite yarn of claim 16 wherein said polymer comprises about 75 to about 85 mole percent lactide with the balance being glycolide.

18. The composite yarn of claim 1 wherein

said core yarn component is made up of one or more biocompatible, essentially non-bioabsorbable, elastic filaments, and

said braided sheath yarn component comprises individual sheath yarn filaments or filament bundles which traverse said core yarn component in a braided configuration to provide said braided, tubular sheath yarn component.

19. The composite yarn of claim 18 wherein said sheath yarn component comprises sheath yarn filaments or filament bundles of different chemical composition.

20. The composite yarn of claim 19 wherein a portion of said sheath yarn filaments or bundles is formed of a polymer exhibiting relatively slow bioabsorption and a remainder of said sheath yarn filaments or bundles is formed of a polymer exhibiting relatively fast bioabsorption.

21. The composite yarn of claim 20 wherein said polymer exhibiting relatively slow bioabsorption is polylactide or a copolymer comprising a high lactide mole percentage and said polymer exhibiting relatively fast bioabsorption is polyglycolide or a copolymer comprising a high glycolide mole percentage.

22. The composite yarn of claim 21 wherein about 30 to 70% by weight of said sheath yarn filaments or bundles is formed of said polylactide or copolymer comprising a high lactide mole percentage and the remainder of said sheath yarn filaments or bundles is formed of said glycolide or copolymer comprising a high glycolide mole percentage.

23. The composite yarn of claim 22 wherein said core yarn filaments are manufactured from a family of copolyester elastomers based on (soft) polyether segments and (hard) polyester segments.

24. The composite yarn of claim 1 in which the sheath yarn component possesses a straight tensile strength of at least about 30,000 p.s.i.

25. The composite yarn of claim 24 in which the sheath yarn component possesses a straight tensile strength of at least about 60,000 p.s.i.

26. The composite yarn of claim 25 in which the sheath yarn component possesses a straight tensile strength of at least about 90,000 p.s.i.

27. The composite yarn of claim 1 in which the overall denier of the core yarn component and/or sheath yarn component is from about 20 to about 600 and the overall denier of the composite yarn is from about 40 to about 1,200.

28. The composite yarn of claim 27 in which the overall denier of the core yarn component and/or sheath yarn component is from about 40 to about 300 and the overall denier of the composite yarn is from about 80 to about 600.

29. The composite yarn of claim 1 wherein the core yarn component represents from about 20% to about 80% of the total weight of the composite yarn.

30. The composite yarn of claim 29 wherein the core yarn component represents from about 30% to about 70% of the total weight of the composite yarn.

31. The composite yarn of claim 1 wherein a hydrophilic coating is applied to the core yarn component.

32. A connective tissue prothesis manufactured from said synthetic, semiabsorbable composite yarn of claim 1.

33. The connective tissue prothesis of claim 32 comprising:

a) a core made up of said synthetic, semiabsorbable composite yarn extending in the lengthwise direction; and

b) a sheath surrounding said core and being fabricated from biocompatible yarn.

34. The connective tissue prothesis of claim 33 wherein said sheath is also manufactured from said synthetic, semiabsorbable composite yarn.

35. The connective tissue prothesis of claim 32 comprising a tubular component fabricated from said synthetic, semiabsorbable composite yarn.

36. Method of manufacturing said synthetic, semiabsorbable composite yarn of claim 1, comprising:

feeding said core component through a hollow spindle of a carrier braider, and

braiding said sheath component from at least one rotating supply bobbin about said core component as said core component emerges from said hollow spindle in said carrier braider.

37. The method of claim 36, wherein filaments or filament bundles of different chemical composition are braided as said sheath component about said core component.