Expandable cannula

• US 5,674,240 A
• Filed: 06/06/1995
• Issued: 10/07/1997
• Est. Priority Date: 02/04/1993
• Status: Expired due to Term

• Current Assignee: Bonutti Skeletal Innovations LLC (Acacia Research Corporation)
• Original Assignee: Peter M. Bonutti
• Inventors: Bonutti, Peter M., Hawkins, James S.
• Primary Examiner(s): DAWSON, GLENN K
• Application Number:
  US08/467,002
• Time in Patent Office: 854 Days
• Field of Search: 604/164, 604/264, 604/272, 604/280, 604/282, 606/1, 606/167, 606/185, 606/190-198, 600/201
• US Class Current: 606/198
• CPC Class Codes: A61B 17/0401 Suture anchors, buttons or pledgets, i.e. means for attaching sutures to bone, cartilage or soft tissue; Instruments for applying or removing suture anchors A61B17/0642 takes precedence; fixation devices for tendons or ligaments A61F2/0811
• CPC Class Codes: A61B 17/06066 Needles, e.g. needle tip configurations making needles B21G1/00
• CPC Class Codes: A61B 17/3417 Details of tips or shafts, e.g. grooves, expandable, bendable; Multiple coaxial sliding cannulas, e.g. for dilating syringe needles A61M5/32; dilators A61M29/00
• CPC Class Codes: A61B 17/3431 being collapsible, e.g. made of thin flexible material A61B17/3423 takes precedence
• CPC Class Codes: A61B 17/3439 with means for changing the inner diameter of the cannula, e.g. expandable A61B17/3423, A61B17/3431 take precedence; catheters A61M25/0662
• CPC Class Codes: A61B 2017/0409 Instruments for applying suture anchors
• CPC Class Codes: A61B 2017/0414 having a suture-receiving opening, e.g. lateral opening
• CPC Class Codes: A61B 2017/0417 T-fasteners
• CPC Class Codes: A61B 2017/06052 Needle-suture combinations in which a suture is extending inside a hollow tubular needle, e.g. over the entire length of the needle
• CPC Class Codes: A61B 2017/3486 Balloon
• CPC Class Codes: A61M 2025/0024 Expandable catheters or sheaths
• CPC Class Codes: A61M 2025/0089 Single injection needle protruding axially, i.e. along the longitudinal axis of the catheter, from the distal tip
• CPC Class Codes: A61M 2025/0095 being one or more needles protruding from the distal tip and which are not used for injection nor for electro-stimulation, e.g. for fixation purposes
• CPC Class Codes: A61M 25/0084 being one or more injection needles
• CPC Class Codes: A61M 25/04 in the body, e.g. expansible A61M25/10, A61M16/0488 take precedence
• CPC Class Codes: A61M 25/06 Body-piercing guide needles or the like
• CPC Class Codes: A61M 25/0662 Guide tubes

Abstract

Cannulas for surgical and medical use expand along their entire lengths. The cannulas are inserted through tissue when in an unexpanded condition and with a small diameter. The cannulas are then expanded radially outwardly to give a full-size instrument passage. Expansion of the cannulas occurs against the viscoelastic resistance of the surrounding tissue. The expandable cannulas do not require a full depth incision, or at most require only a needle-size entrance opening. In one embodiment of the invention, the cannula has a pointed end portion. In this embodiment of the invention, the cannula includes wires having cores which are enclosed by jackets. The jackets are integrally formed as one piece with a sheath of the cannula. The cannula may be expanded by inserting members or by fluid pressure. The cannula is advantageously utilized to expand a vessel, such as a blood vessel. An expandable chamber may be provided at the distal end of the cannula.

Claims

1. An expandable cannula having a contracted condition and being expandable from the contracted condition to an expanded condition, said expandable cannula comprising a longitudinally extending tubular sheath formed of a material capable of being extended from a condition in which a longitudinally extending passage through the tubular sheath has a relatively small cross sectional size to a condition in which the passage has a relatively large cross sectional size upon expansion of said cannula from the contracted condition to the expanded condition, a plurality of wires which are enclosed by said sheath and extend along an inner side of said sheath, said wires being disposed in a longitudinally extending array having a relatively small cross sectional size when said cannula is in the contracted condition and a relatively large cross sectional size when said cannula is in the expanded condition, and a pointed end portion for piercing body tissue, said pointed end portion of said cannula being formed by an end portion of said sheath and end portions of said wires.

2. An expandable cannula as set forth in claim 1 wherein said wires have exposed end portions at said pointed end portion of said cannula to enable said end portions of said wires to engage body tissue during piercing of body tissue by said pointed end portion of said cannula.

3. An expandable cannula as set forth in claim 1 wherein said sheath has a leading end surface which engages body tissue at locations between adjacent wires during piercing of body tissue by said pointed end portion of said cannula.

4. An expandable cannula as set forth in claim 1 wherein each of said wires includes a longitudinally extending core and a jacket of polymeric material, said jacket of polymeric material being connected with said sheath.

5. An expandable cannula as set forth in claim 4 wherein an end portion of a core of at least one of said wires is exposed at said pointed end portion of said cannula to enable said core of said one wire to engage body tissue during piercing of body tissue by said pointed end portion of said cannula.

6. An expandable cannula as set forth in claim 4 wherein an end portion of a core of at least one of said wires is completely enclosed by said sheath and said jacket at said pointed end portion of said cannula to block engagement of body tissue with said core of said one wire during piercing of body tissue by said pointed end portion of said cannula.

7. An expandable cannula as set forth in claim 4 wherein an end portion of a core of at least one of said wires extends beyond an outer end portion of said sheath to enable said core of said one wire to engage body tissue ahead of said sheath during piercing of body tissue by said pointed end portion of said cannula.

8. An expandable cannula as set forth in claim 1 wherein at least a portion of each of said wires is integrally formed as one piece with said sheath to interconnect said wires and said sheath.

9. An expandable cannula as set forth in claim 1 wherein each of said wires includes a longitudinally extending core having generally circular cross sectional configuration and a jacket which at least partially encloses said core, said jacket being integrally formed as one piece with said sheath to interconnect said core and said sheath.

10. An expandable cannula as set forth in claim 1 wherein each of said wires includes a longitudinally extending core formed of metal and a jacket which at least partially encloses said core, said jacket and said sheath being integrally formed as one piece of polymeric material.

11. An expandable cannula as set forth in claim 1 wherein said cannula has an oval cross sectional configuration as viewed in a plane perpendicular to a longitudinal axis of said cannula when said cannula is in the expanded condition.

12. An expandable cannula as set forth in claim 1 wherein said cannula has a circular cross sectional configuration as viewed in a plane perpendicular to a longitudinal axis of said cannula when said cannula is in the expanded condition.

13. An expandable cannula as set forth in claim 1 further including an insert insertable into the passage in said tubular sheath to effect expansion of said tubular sheath from a first cross sectional area to a second cross sectional area during expansion of said cannula from the contracted condition to the expanded condition, said second cross sectional area being larger than said first cross sectional area, each of said wires having an outer side surface which is engageable by said insert to enable each of said wires to transmit force from said insert to said sheath.

14. An expandable cannula as set forth in claim 13 wherein said outer side surface of each of said wires is integrally formed as one piece with said sheath.

15. An expandable cannula as set forth in claim 13 wherein said insert is engageable with the outer side surface of at least some of said wires in said pointed end portion of said cannula.

16. An expandable cannula as set forth in claim 1 wherein said wires have longitudinally extending outer side surface areas forming contact surfaces for contacting a member insertable into the passage in said tubular sheath, each of said wires adapted to block engagement of a longitudinally extending portion of said sheath with the member when the member is inserted into the passage in said sheath.

17. An expandable cannula as set forth in claim 16 wherein said longitudinally extending outer side surface areas on said wires are integrally formed as one piece with said sheath.

18. An expandable cannula having a contracted condition and being expandable from the contracted condition to an expanded condition upon insertion of a member into said cannula, said expandable cannula comprising a longitudinally extending tubular sheath formed of a material capable of being expanded from a condition in which a longitudinally extending passage through the tubular sheath has a relatively small cross sectional size to a condition in which the passage has a relatively large cross sectional size upon expansion of said cannula from the contracted condition to the expanded condition, and a plurality of wires enclosed by said sheath and extending along an inner side of said sheath, said wires being disposed in a longitudinally extending array having a relatively small cross sectional size when said cannula is in the contracted condition and a relatively large cross sectional size when said cannula is in the expanded condition, each of said wires having a longitudinally extending outer side surface area which is engageable with the member upon insertion of the member into the passage in said sheath to block engagement of the member with longitudinally extending inner side surface areas on said sheath, said longitudinally extending outer side surface areas on said wires being integrally formed as one piece with said sheath, at least a portion of one of said wires extends beyond an outer end portion of said sheath to enable said one of said wires to engage body tissue ahead of said sheath upon insertion of said outer end portion of said sheath into body tissue.

19. An apparatus as set forth in claim 18 wherein each of said wires includes a longitudinally extending metal core and a jacket formed of polymeric material and enclosing at least a portion of said core, said core of said one of said wires extending beyond said jacket of said one of said wires to enable said metal core of said one of said wires to engage body tissue ahead of said sheath upon insertion of said outer end portion of said sheath into body tissue.

20. An apparatus as set forth in claim 18 wherein each of said wires includes a longitudinally extending metal core and a jacket formed of polymeric material and enclosing at least a portion of said core, said core of said one of said wires is completely enclosed by said sheath and one of said jackets at said outer end portion of said sheath.

21. An expandable cannula as set forth in claim 18 wherein said sheath has an outer side surface adapted to press against an inner side surface of a blood vessel to expand the blood vessel upon insertion of the member into said cannula and expansion of said cannula from the contracted condition to an expanded condition with an end portion of said cannula in a blood vessel.

22. An expandable cannula having a contracted condition and being expandable from the contracted condition to an expanded condition upon insertion of a member into said cannula, said expandable cannula comprising a longitudinally extending tubular sheath formed of a material capable of being expanded from a condition in which a longitudinally extending passage through the tubular sheath has a relatively small cross sectional size to a condition in which the passage has a relatively large cross sectional size upon expansion of said cannula from the contracted condition to the expanded condition, and a plurality of wires enclosed by said sheath and extending along an inner side of said sheath, said wires being disposed in a longitudinally extending array having a relatively small cross sectional size when said cannula is in the contracted condition and a relatively large cross sectional size when said cannula is in the expanded condition, each of said wires having a core formed of a first material and a jacket which extends at least part way around said core and is formed of a second material which is different than said first material, said jacket having a longitudinally extending outer side surface area which is engageable with the member upon insertion of the member into the passage in said sheath to block engagement of the member with longitudinally extending inner side surface areas on said sheath, at least a portion of one of said wires extends beyond an outer end portion of said sheath to enable said one of said wires to engage body tissue ahead of said sheath upon insertion of said outer end portion of said sheath into body tissue.

23. An expandable cannula having a contracted condition and being expandable from the contracted condition to an expanded condition upon insertion of a member into said cannula, said expandable cannula comprising a longitudinally extending tubular sheath formed of a material capable of being expanded from a condition in which a longitudinally extending passage through the tubular sheath has a relatively small cross sectional size to a condition in which the passage has a relatively large cross sectional size upon expansion of said cannula from the contracted condition to the expanded condition, and a plurality of wires enclosed by said sheath and extending along an inner side of said sheath, said wires being disposed in a longitudinally extending array having a relatively small cross sectional size when said cannula is in the contracted condition and a relatively large cross sectional size when said cannula is in the expanded condition, each of said wires having a core formed of a first material and a jacket which extends at least part way around said core and is formed of a second material which is different than said first material, said jacket having a longitudinally extending outer side surface area which is engageable with the member upon insertion of the member into the passage in said sheath to block engagement of the member with longitudinally extending inner side surface areas on said sheath, said cannula having a pointed end portion to pierce body tissue, said pointed end portion of said cannula being formed by an end portion of said sheath and end portions of said jackets and cores of said wires, said jackets being integrally formed as one piece with said sheath at said pointed end portion of said cannula.

24. An expandable cannula as set forth in claim 23 wherein said wires have exposed outer ends at said pointed end portion of said cannula to enable said ends of said wires to engage body tissue upon insertion of said pointed end portion of said cannula into body tissue.

25. An expandable cannula as set forth in claim 23 wherein said sheath has an outer end surface which engages body tissue at locations between adjacent wires during insertion of said pointed end portion of said cannula through an imperforate surface on body tissue.

26. An expandable cannula as set forth in claim 23 wherein said sheath has an outer side surface which is adapted to press against an inner side surface of a blood vessel upon insertion of the member into said cannula and expansion of said cannula from the contracted condition to an expanded condition when the pointed end portion of said cannula is introduced into a blood vessel.

27. An expandable cannula as set forth in claim 23 wherein an end portion of a core of at least one of said wires is exposed at said pointed end portion of said cannula to enable said core of said one wire to engage body tissue during insertion of said pointed end portion of said cannula into body tissue.

28. An expandable cannula as set forth in claim 23 wherein an end portion of a core of each of said wires is completely enclosed by said sheath and said jacket at said pointed end portion of said cannula to block engagement of body tissue with said cores of said wires during insertion of said pointed end portion of said cannula into body tissue.

29. An expandable cannula as set forth in claim 23 wherein at least a portion of one of said wires extends beyond said end portion of said sheath to enable said one of said wires to engage body tissue ahead of said sheath upon insertion of said end portion of said sheath into body tissue.

30. An expandable cannula as set forth in claim 23 wherein said wires have parallel longitudinal axes which extend parallel to a longitudinal central axis of said cannula.

31. A cannula comprising a longitudinally extending tubular sheath, a plurality of wires which are enclosed by said sheath and extend along an inner side of said sheath, said wires having parallel longitudinal axes which extend parallel to a longitudinal central axis of said sheath, and an end portion having surface means for piercing body tissue, said end portion of said cannula being formed by an end portion of said sheath and end portions of said wires, said surface means for piercing body tissue being at least partially disposed on said end portion of said sheath and on said end portions of said wires.

32. A cannula as set forth in claim 31 wherein said wires have exposed end portions at said end portion of said cannula to enable said end portions of said wires to engage body tissue during piercing of body tissue by said end portion of said cannula.

33. A cannula as set forth in claim 31 wherein said sheath has a leading end surface which engages body tissue at locations between adjacent wires during piercing of body tissue by said end portion of said cannula.

34. A cannula as set forth in claim 31 wherein each of said wires includes a longitudinally extending core and a jacket of polymeric material, said jacket of polymeric material being connected with said sheath.

35. A cannula as set forth in claim 34 wherein an end portion of a core of at least one of said wires is exposed at said end portion of said cannula to enable said core of said one wire to engage body tissue during piercing of body tissue by said end portion of said cannula.

36. A cannula as set forth in claim 34 wherein an end portion of a core of at least one of said wires is completely enclosed by said sheath and said jacket at said end portion of said cannula to block engagement of body tissue with said core of said one wire during piercing of body tissue by said end portion of said cannula.

37. A cannula as set forth in claim 34 wherein an end portion of a core of at least one of said wires extends beyond an outer end portion of said sheath to enable said core of said one wire to engage body tissue ahead of said sheath during piercing of body tissue by said end portion of said cannula.

38. A cannula as set forth in claim 31 wherein at least a portion of each of said wires is integrally formed as one piece with said sheath to interconnect said wires and said sheath.

39. A cannula as set forth in claim 31 wherein each of said wires includes a longitudinally extending core having generally circular cross sectional configuration and a jacket which at least partially encloses said core, said jacket being integrally formed as one piece with said sheath to interconnect said core and said sheath.

40. A cannula as set forth in claim 31 wherein each of said wires includes a longitudinally extending core formed of metal and a jacket which at least partially encloses said core, said jacket and said sheath being integrally formed as one piece of polymeric material.

41. A cannula as set forth in claim 31 further including an insert insertable into a passage in said tubular sheath to effect expansion of said tubular sheath from a first cross sectional area to a second cross sectional area, said second cross sectional area being larger than said first cross sectional area, each of said wires having an outer side surface which is engageable by said insert to enable each of said wires to transmit force from said insert to said sheath.

42. A cannula as set forth in claim 41 wherein said outer side surface of each of said wires is integrally formed as one piece with said sheath.

43. A cannula as set forth in claim 41 wherein said insert is engageable with the outer side surface of at least some of said wires in said end portion of said cannula.

44. A cannula as set forth in claim 31 wherein said wires have longitudinally extending outer side surface areas forming contact surfaces for contacting a member insertable into said tubular sheath, each of said wires adapted to block engagement of a longitudinally extending portion of said sheath with the member when the member is inserted into said sheath.

45. A cannula as set forth in claim 44 wherein said longitudinally extending outer side surface areas on said wires are integrally formed as one piece with said sheath.

46. A cannula comprising a longitudinally extending tubular sheath, a plurality of wires which are enclosed by said sheath, and a pointed end portion for piercing body tissue, said pointed end portion of said cannula being formed by a pointed end portion of said sheath and said wires, said sheath having a longitudinal central passage which extends through said pointed end portion of said sheath, said wires being connected with an inner side of said central passage in said sheath at said pointed end portion of said sheath, said wires having parallel central axes which extend parallel to a central axis of said pointed end portion of said sheath.

47. A cannula as set forth in claim 46 wherein said pointed end portion of said sheath is formed of a material capable of being extended from a condition in which said pointed end portion of said sheath has a relatively small cross sectional size to a condition in which the pointed end portion of said sheath has a relatively large cross sectional size upon movement of a member through a portion of the longitudinal central passage disposed in said pointed end portion of said sheath.

48. A cannula as set forth in claim 46 wherein said wires have exposed ends at said pointed end portion of said sheath to enable said ends of said wires to engage body tissue during insertion of said pointed end portion of said sheath into body tissue.

49. A cannula as set forth in claim 46 wherein said sheath has a leading end surface which engages body tissue at locations between adjacent wires during insertion of said pointed end portion of said sheath into body tissue.

50. A cannula as set forth in claim 46 wherein each of said wires includes a longitudinally extending core and a jacket of polymeric material, said jacket of polymeric material being connected with said sheath at said pointed end portion of said sheath, said core and said jacket of each of said wires having longitudinal central axes which extend parallel to the central axis of said pointed end portion of said sheath.

51. A cannula as set forth in claim 50 wherein an end portion of a core of at least one of said wires is exposed at said pointed end portion of said sheath to enable said core of said one wire to engage body tissue during insertion of said pointed end portion of said sheath into body tissue.

52. A cannula as set forth in claim 50 wherein an end of a core of at least one of said wires is completely enclosed by said sheath and said jacket at said pointed end portion of said sheath to block engagement of body tissue with said core of said one wire during insertion of said pointed end portion of said sheath into body tissue.

53. A cannula as set forth in claim 50 wherein an end portion of a core of at least one of said wires extends beyond said pointed end portion of said sheath and beyond a jacket of said one of said wires to enable said core of said one of said wires to engage body tissue ahead of said sheath during insertion of said pointed end portion of said sheath into body tissue.

54. A cannula as set forth in claim 46 wherein at least a portion of each of said wires is integrally formed as one piece with said pointed end portion of said sheath to interconnect said wires and said pointed end portion of said sheath.

55. A cannula as set forth in claim 46 wherein each of said wires includes a longitudinally extending core having generally circular cross sectional configuration and a jacket which at least partially encloses said core, said jacket being integrally formed as one piece with said pointed end portion of said sheath to interconnect said core and said pointed end portion of said sheath.

56. An expandable cannula as set forth in claim 46 wherein each of said wires includes a longitudinally extending core formed of metal and a jacket which at least partially encloses said core, said jacket and core extending along said sheath between said pointed end portion of said sheath and an end portion of said sheath opposite from said pointed end portion.

57. A cannula as set forth in claim 46 further including an insert movable along the passage in said pointed end portion of said sheath to effect expansion of said pointed end portion of said sheath from a first cross sectional area to a second cross sectional area, said second cross sectional area being larger than said first cross sectional area, each of said wires having an outer side surface which is engageable by said insert to enable each of said wires to transmit force from said insert to said pointed end portion of said sheath and to enable said wires to block engagement of parallel longitudinally extending portions of an inner side of the passage through said pointed end portion of said sheath with the insert.

58. A cannula as set forth in claim 57 wherein said outer side surface of each of said wires is integrally formed as one piece with said pointed end portion of said sheath.

59. A cannula as set forth in claim 46 wherein said wires have longitudinally extending outer side surface areas forming contact surfaces for contacting a member insertable into said pointed end portion of said sheath, each of said wires adapted to block engagement of a portion of said pointed end portion of said sheath with the member when the member is inserted into said pointed end portion of said sheath.

60. A cannula as set forth in claim 59 wherein said longitudinally extending outer side surface areas on said wires are integrally formed as one piece with said pointed end portion of said sheath.

61. A cannula as set forth in claim 46 wherein said wires extend through a portion of said sheath disposed between said pointed end portion of said sheath and an end portion of said sheath opposite from said pointed end portion of said sheath.

62. A cannula comprising a longitudinally extending tubular sheath, said sheath having an end portion which is insertable into body tissue, and an array of wires which extend along an inner side of said sheath, said wires in said array of wires having longitudinal central axes which extend parallel to a longitudinal central axis of said sheath, said array of wires including at least one wire having a piercing end portion which extends outward from said end portion of said sheath to enable said one wire to pierce an imperforate surface on body tissue and initiate the formation of an opening in the imperforate surface on the body tissue when said end portion of said sheath is to be inserted into body tissue.

63. A cannula as set forth in claim 62 wherein said one wire is at least partially formed of metal.

64. A cannula as set forth in claim 62 wherein said sheath is formed of a material capable of being expanded from a condition in which a longitudinally extending passage through the sheath has a relatively small cross sectional size to a condition in which the passage has a relatively large cross sectional size upon insertion of a member into the sheath and movement of the member along the array of wires toward said end portion of said sheath, each of said wires having an outer side surface which is engageable by the member to enable each of said wires to transmit force from the member to said sheath.