Surgical fixing device for two bone parts

• US 20070270856A1
• Filed: 04/12/2007
• Published: 11/22/2007
• Est. Priority Date: 04/28/2006
• Status: Active Grant

• Current Assignee: Aesculap AG (B. Braun Holding GmbH & Co. KG)
• Original Assignee: Aesculap AG (B. Braun Holding GmbH & Co. KG)
• Inventors: Weisshaupt, Dieter, Morales, Pedro, Dworschak, Manfred, Lutze, Theodor
• Granted Patent: US 7,867,262 B2
• Time in Patent Office: Days
• US Class Current: 606/328
• CPC Class Codes: A61B 17/688 for reattaching pieces of the skull
• CPC Class Codes: A61B 17/823 for the sternum

Abstract

A surgical fixing device for the fixing of adjacent bone parts is provided. A first engaging element is provided for engaging the underside of the two bone parts and a second engaging element is provided for engaging the upper side of the bone parts. A tensioning device connects the two engaging elements to each other through an interspace between the bone parts and permanently fixes the two engaging elements with respect to each other in a tensioned manner when they engage the underside and the upper side of the bone parts. To make it easier to apply the fixing device, at least one elastic tensioning element is provided which displaces a supporting surface applied to the upper side of the bone parts toward the first engaging element, so that the supporting surface and the first engaging element can be moved away from each other against the force of the elastic tensioning element.

Claims

1. Surgical fixing device for the fixing together of two adjacent bone parts, comprising:

a first engaging element for engaging an underside of the two bone parts;

a second engaging element for engaging an upper side of the two bone parts;

a tensioning device adapted to connect the two engaging elements to each other through an interspace between the bone parts and to permanently fix the two engaging elements with respect to each other in a tensioned manner when the first and second engaging elements respectively engage the underside and the upper side of the bone parts; and

at least one elastic tensioning element adapted to displace a supporting surface applied to the upper side of the bone parts toward the first engaging element, so that the supporting surface and the first engaging element are moveable away from each other against the force of the elastic tensioning element.

2. Fixing device in accordance with claim 1, wherein the supporting surface is part of the elastic tensioning element.

3. Fixing device in accordance with claim 2, wherein the supporting surface is disposed between the two engaging elements before the fixing device is applied to the bone parts.

4. Fixing device in accordance with claim 2, wherein the elastic tensioning element is releasably connected to the fixing device.

5. Fixing device in accordance with claim 4, wherein the elastic tensioning element is held on the tensioning device.

6. Fixing device in accordance with claim 5, wherein:

the tensioning device has at least one rod that is held on the first engaging element, extends through said interspace, and passes through the second engaging element; and

the elastic tensioning element is held on said at least one rod.

7. Fixing device in accordance with claim 6, wherein the elastic tensioning element is held at a free end of the at least one rod.

8. Fixing device in accordance with claim 6, wherein:

the tensioning device has two rods disposed next to each other; and

the elastic tensioning element has a cross-piece connecting the two rods.

9. Fixing device in accordance with claim 6, wherein the tensioning element carries at least one clamping element which releasably fixes the tensioning element on the at least one rod.

10. Fixing device in accordance with claim 6, wherein:

the tensioning element has a spring arm which connects the supporting surface and the location where said tensioning element is connected to the tensioning device; and

said spring arm extends laterally past the second engaging element.

11. Fixing device in accordance with claim 6, wherein the tensioning element carries a grip extending beyond the tensioning device.

12. Fixing device in accordance with claim 2, wherein the elastic tensioning element is supported on the second engaging element.

13. Fixing device in accordance with claim 12, wherein:

the elastic tensioning element is pushable laterally in between the upper side of the bone parts and an underside of the second engaging element; and

said elastic tensioning element is pushable laterally out from between the upper side of the bone parts and the underside of the second engaging element when the fixing device engages the bone parts.

14. Fixing device in accordance with claim 12, wherein the elastic tensioning element is a bow spring.

15. Fixing device in accordance with claim 14, wherein the bow spring is U-shaped, with a first arm that forms the supporting surface, a second arm adapted to be applied to the second engaging element, and a resilient cross-piece that connects the two arms.

16. Fixing device in accordance with claim 12, wherein:

the tensioning device has at least one rod that is held on the first engaging element, extends through said interspace, and passes through the second engaging element; and

the tensioning element is disposed on both sides of the at least one rod.

17. Fixing device in accordance with claim 16, wherein the tensioning element has a slit-shaped cut-out, which is entered by the at least one rod of the tensioning device when the elastic tensioning element is pushed in between the upper side of the bone parts and an underside of the second engaging element.

18. Fixing device in accordance with claim 13, wherein:

at least one arresting member is provided, which arresting member secures the elastic tensioning element to prevent said elastic tensioning element from being pushed out when in a pushed-in state; and

the arresting member can be released by displacing forces exceeding a limit value.

19. Fixing device in accordance with claim 18, wherein the arresting member is formed by interengaging projections and recesses on the elastic tensioning element and on the second engaging element.

20. Fixing device in accordance with claim 19, wherein the supporting surface is formed such that it rises up at an edge thereof that is at a front portion of said supporting surface during pulling out from between the upper side of the bone parts and the underside of the second engaging element.

21. Fixing device in accordance with claim 13, wherein the elastic tensioning element carries a grip that extends laterally beyond the second engaging element in a pushed-in state of the elastic tensioning element.

22. Fixing device in accordance with claim 1, wherein the supporting surface is formed by the second engaging element.

23. Fixing device in accordance with claim 22, further comprising a stop which limits the extent to which the two engaging elements come together under the action of the elastic tensioning element.

24. Fixing device in accordance with claim 22, wherein the elastic tensioning element comprises at least one elastically extensible pull member, which acts on the two engaging elements and draws them elastically toward each other.

25. Fixing device in accordance with claim 24, wherein the pull member is in the form of a closed loop surrounding the two engaging elements.

26. Fixing device in accordance with claim 24, wherein:

the pull member is disposed between the two engaging elements; and

each end of the pull member is fixed on a respective one of said engaging elements.

27. Fixing device in accordance with claim 22, wherein the elastic tensioning element engages an upper side of the second engaging element and is supported on the tensioning device.

28. Fixing device in accordance with claim 22, wherein:

the elastic tensioning element is formed by at least one resilient part of the second engaging element; and

the at least one resilient part is supported on the tensioning device.

29. Fixing device in accordance with claim 27, wherein:

the tensioning device has at least one rod that is held on the first engaging element and passes through the second engaging element; and

a supporting member for the elastic tensioning element is held on the at least one rod.

30. Fixing device in accordance with claim 29, wherein:

the at least one rod comprises a single rod;

the supporting member is a tensioning disk that is displaceable on the rod only in a direction of the two engaging elements; and

the tensioning disk permanently tensions the two engaging elements with respect to each other in an applied state of the fixing device.

31. Fixing device in accordance with claim 29, wherein the supporting member is disposed at a free end of the rod.

32. Fixing device in accordance with claim 31, wherein the supporting member is releasably fitted or screwed onto the free end of the rod.

33. Fixing device in accordance with claim 29, wherein the elastic tensioning element is a helical spring surrounding the rod.

34. Fixing device in accordance with claim 1, wherein each of the engaging elements carry pointed fixing projections that point in the direction of the respective other engaging element.

35. Fixing device in accordance with claim 34, wherein the fixing projections are inclined with respect to the tensioning device of the two engaging elements.

36. A method for fixing together two adjacent bone parts, comprising:

positioning a first engaging element against an underside of a first of two bone parts;

positioning a second engaging element at preset distance above an upper side of the first bone part;

connecting the first and second engaging elements to each other via a tensioning device extending through an interspace between the bone parts;

displacing a supporting surface applied to the upper side of the bone parts toward the first engaging element using at least one elastic tensioning element, so that the first engaging element is tensioned against the underside of the first bone part and is moveable away from the supporting surface against the force of the elastic tensioning element;

moving a second of said two bone parts laterally towards said first bone part until said second bone part abuts said tensioning device extending through said interspace between said bone parts and an underside of said second bone part engages with said first engaging element; and

tensioning the second engaging element with respect to the first engaging element using said tensioning device such that the engaging elements respectively engage the upper side and the underside of the bone parts.

37. A method in accordance with claim 36, wherein the supporting surface is part of the elastic tensioning element.

38. A method in accordance with claim 37, wherein the supporting surface is disposed between the two engaging elements before the fixing device is applied to the bone parts.

39. A method in accordance with claim 37, wherein the elastic tensioning element is releasably connected to the fixing device.

40. A method in accordance with claim 39, wherein the elastic tensioning element is held on the tensioning device.

41. A method in accordance with claim 40, wherein:

the tensioning device has at least one rod that is held on the first engaging element, extends through said interspace, and passes through the second engaging element; and

the elastic tensioning element is held on said at least one rod.

42. A method in accordance with claim 41, wherein the elastic tensioning element is held at a free end of the at least one rod.

43. A method in accordance with claim 41, wherein:

the tensioning device has two rods disposed next to each other; and

the elastic tensioning element has a cross-piece connecting the two rods.

44. A method in accordance with claim 41, wherein the tensioning element carries at least one clamping element which releasably fixes the tensioning element on the at least one rod.

45. A method in accordance with claim 41, wherein:

the tensioning element has a spring arm which connects the supporting surface and the location where said tensioning element is connected to the tensioning device; and

said spring arm extends laterally past the second engaging element.

46. A method in accordance with claim 41, wherein the tensioning element carries a grip extending beyond the tensioning device.

47. A method in accordance with claim 37, wherein the elastic tensioning element is supported on the second engaging element.

48. A method in accordance with claim 47, wherein:

the elastic tensioning element is pushable laterally in between the upper side of the bone parts and an underside of the second engaging element; and

said elastic tensioning element is pushable laterally out from between the upper side of the bone parts and the underside of the second engaging element when the fixing device engages the bone parts.

49. A method in accordance with claim 47, wherein the elastic tensioning element is a bow spring.

50. A method in accordance with claim 49, wherein the bow spring is U-shaped, with a first arm that forms the supporting surface, a second arm adapted to be applied to the second engaging element, and a resilient cross-piece that connects the two arms.

51. A method in accordance with claim 47, wherein:

the tensioning device has at least one rod that is held on the first engaging element, extends through said interspace, and passes through the second engaging element; and

the tensioning element is disposed on both sides of the at least one rod.

52. A method in accordance with claim 51, wherein the tensioning element has a slit-shaped cut-out, which is entered by the at least one rod of the tensioning device when the elastic tensioning element is pushed in between the upper side of the bone parts and an underside of the second engaging element.

53. A method in accordance with claim 48, wherein:

at least one arresting member is provided, which arresting member secures the elastic tensioning element to prevent said elastic tensioning element from being pushed out when in a pushed-in state; and

the arresting member can be released by displacing forces exceeding a limit value.

54. A method in accordance with claim 53, wherein the arresting member is formed by interengaging projections and recesses on the elastic tensioning element and on the second engaging element.

55. A method in accordance with claim 54, wherein the supporting surface is formed such that it rises up at an edge thereof that is at a front portion of said supporting surface during pulling out from between the upper side of the bone parts and the underside of the second engaging element.

56. A method in accordance with claim 48, wherein the elastic tensioning element carries a grip that extends laterally beyond the second engaging element in a pushed-in state of the elastic tensioning element.

57. A method in accordance with claim 36, wherein the supporting surface is formed by the second engaging element.

58. A method in accordance with claim 57, further comprising a stop which limits the extent to which the two engaging elements come together under the action of the elastic tensioning element.

59. A method in accordance with claim 57, wherein the elastic tensioning element comprises at least one elastically extensible pull member, which acts on the two engaging elements and draws them elastically toward each other.

60. A method in accordance with claim 59, wherein the pull member is in the form of a closed loop surrounding the two engaging elements.

61. A method in accordance with claim 59, wherein:

the pull member is disposed between the two engaging elements; and

each end of the pull member is fixed on a respective one of said engaging elements.

62. A method in accordance with claim 57, wherein the elastic tensioning element engages an upper side of the second engaging element and is supported on the tensioning device.

63. A method in accordance with claim 57, wherein:

the elastic tensioning element is formed by at least one resilient part of the second engaging element; and

the at least one resilient part is supported on the tensioning device.

64. A method in accordance with claim 57, wherein:

the tensioning device has at least one rod that is held on the first engaging element and passes through the second engaging element; and

a supporting member for the elastic tensioning element is held on the at least one rod.

65. A method in accordance with claim 64, wherein:

the at least one rod comprises a single rod;

the supporting member is a tensioning disk that is displaceable on the rod only in a direction of the two engaging elements; and

the tensioning disk permanently tensions the two engaging elements with respect to each other in an applied state of the fixing device.

66. A method in accordance with claim 64, wherein the supporting member is disposed at a free end of the rod.

67. A method in accordance with claim 66, wherein the supporting member is releasably fitted or screwed onto the free end of the rod.

68. A method in accordance with claim 64, wherein the elastic tensioning element is a helical spring surrounding the rod.

69. A method in accordance with claim 36, wherein each of the engaging elements carry pointed fixing projections that point in the direction of the respective other engaging element.

70. A method in accordance with claim 69, wherein the fixing projections are inclined with respect to the tensioning device of the two engaging elements.

71. A method in accordance with claim 36, wherein said displacing step comprises:

inserting said elastic tensioning device between an underside of the second engaging element and an upper side of said first bone part; and

moving said second engaging element towards said upper side of said first bone part in order to compress the elastic tensioning element and tension the first engaging element against the underside of the first bone part;

further comprising removing said tensioning device after said moving of said second bone part laterally towards said first bone part and prior to moving said second engaging element into contact with said upper sides of said bone parts.

72. A method in accordance with claim 71, wherein said elastic tensioning device comprises a U-shaped bow spring.

73. A method in accordance with claim 71, wherein the tensioning element comprises:

a spring arm which connects the supporting surface and the location where said tensioning element is connected to the tensioning device; and

said spring arm extending laterally past the second engaging element.