Shock absorbing prosthetic foot for use with prosthetic ankle

• US 20050038525A1
• Filed: 06/15/2004
• Published: 02/17/2005
• Est. Priority Date: 05/24/1999
• Status: Abandoned Application

• Current Assignee: Ohio Willow Wood Company
• Original Assignee: Ohio Willow Wood Company
• Inventors: Arbogast, Robert E., Colvin, James M., Doddroe, Jeffrey L., Capper, James W.
• Application Number:
  US10/868,518
• Publication Number:
  US 20050038525A1
• Time in Patent Office: Days
• US Class Current: 623/55
• CPC Class Codes: A61F 2/66 Feet; Ankle joints
• CPC Class Codes: A61F 2002/5003 having damping means, e.g. shock absorbers for implantable joints A61F2002/30563
• CPC Class Codes: A61F 2002/5072 having spring elements spring-biased locking means A61F2002/30505; for implantable joints A61F2002/30565; other elastic means A61F2002/5007
• CPC Class Codes: A61F 2002/5079 Leaf springs A61F2002/6657 takes precedence
• CPC Class Codes: A61F 2002/6657 having a plate-like or strip-like spring element, e.g. an energy-storing cantilever spring keel

Abstract

A low profile prosthetic foot designed for use with a prosthetic ankle. The prosthetic foot includes at least one toe spring and at least one heel spring. The prosthetic foot is able to absorb shocks generated during ambulation of a user of said foot. When a prosthetic ankle is attached to the prosthetic foot, the position (height) of the ankle preferably approximates the position (height) of a typical human ankle.

Claims

1. A low profile prosthetic foot for use with a prosthetic ankle, comprising:

a foot plate having a heel portion and a toe portion spaced along the length thereof;

at least one toe spring having a distal end connected to said toe portion of said foot plate and a proximal end residing some distance above said heel portion of said foot plate; and

at least one heel spring having a first end connected to said heel portion of said foot plate and extending upward such that a second end thereof is connected near said proximal end of said at least one toe spring;

wherein, when connected to said prosthetic foot, the position of a prosthetic ankle will approximate the position of a typical human ankle.

2. The low profile prosthetic foot of claim 1, wherein a pair of toe springs are connected between said toe portion of said foot plate and said at least one heel spring.

3. The low profile prosthetic foot of claim 1, wherein a pair of heel springs are connected between said heel portion of said foot plate and said proximal end of said at least one toe spring.

4. The low profile prosthetic foot of claim 1, further comprising a heel attachment plate disposed between said foot plate and said at least one heel spring.

5. The low profile prosthetic foot of claim 1, further comprising a toe spring support plate disposed between said at least one heel spring and said at least one toe spring.

6. The low profile prosthetic foot of claim 5, wherein said toe spring support plate includes a stop that limits the differential movement of a side of said at least one toe spring that is subjected to compression during bending thereof.

7. The low profile prosthetic foot of claim 1, wherein said at least one heel spring is a pneumatic or hydraulic shock absorber.

8. The low profile prosthetic foot of claim 1, wherein said at least one heel spring is a helical compression spring.

9. The low profile prosthetic foot of claim 1, wherein said at least one heel spring is made from an elastomeric material.

10. The low profile prosthetic foot of claim 9, wherein said at least one heel spring has at least one recess or cavity located therein, said recess or cavity affecting the compressive resistance of said at least one heel spring.

11. The low profile prosthetic foot of claim 10, wherein a secondary heel spring element is located in said recess or cavity, said secondary heel spring element having a compressive modulus that differs from the compressive modulus of the elastomeric material forming said at least one heel spring.

12. The low profile prosthetic foot of claim 9, wherein said at least one heel spring is a U-shaped element, a rounded end of which is adapted for connection to said foot plate.

13. The low profile prosthetic foot of claim 9, further comprising a threaded fastener embedded in one, or both, ends of said at least one heel spring.

14. The low profile prosthetic foot of claim 9, further comprising a fiber reinforcement material embedded in said elastomeric material.

15. The low profile prosthetic foot of claim 1, further comprising at least one auxiliary toe spring disposed below said at least one toe spring.

16. The low profile prosthetic foot of claim 15, further comprising a spacer plate disposed between said at least one toe spring and said at least one auxiliary toe spring.

17. The low profile prosthetic foot of claim 16, further comprising a recess in said spacer plate for receiving a proximal portion of said at least one toe spring.

18. The low profile prosthetic foot of claim 17, wherein said recess acts to limit the differential movement of a side of said at least one toe spring that is subjected to compression during bending thereof.

19. The low profile prosthetic foot of claim 16, further comprising a stop on said spacer plate that limits the differential movement of a side of said at least one toe spring that is subjected to compression during bending thereof.

20. The low profile prosthetic foot of claim 1, wherein said at least one toe spring is secured to said at least one heel spring by passing at least one fastener through a prosthetic ankle, through said at least one toe spring, and into said at least one heel spring.

21. The low profile prosthetic foot of claim 1, wherein said at least one toe spring is molded to one end of said at least one heel spring.

22. The low profile prosthetic foot of claim 1, wherein one end of said at least one heel spring is molded to said foot plate.

23. The low profile prosthetic foot of claim 1, wherein said distal end of said at least one toe spring is connected to said foot plate by a toe spring clamp assembly that is molded to said foot plate.

57. The low profile prosthetic foot of claim 1, wherein a pair of heel springs reside between said heel portion of said foot plate and said proximal end of said at least one toe spring.

24. A low profile prosthetic foot assembly, comprising:

a foot plate having a heel portion and a toe portion spaced along the length thereof;

at least one toe spring having a distal end connected to said toe portion of said foot plate, said at least one toe spring extending upward at an angle to a proximal end located above said heel portion of said foot plate;

at least one heel attachment plate, said at least one heel attachment plate adapted for connection to said heel portion of said foot plate and to one end of a heel spring;

at least one toe spring support plate, said at least one toe spring support plate adapted for connection to a proximal end of said at least one toe spring and to an opposite end of a heel spring;

at least one heel spring, said at least one heel spring extending upward from said foot plate toward said at least one toe spring and disposed between said at least one heel attachment plate and said at least one toe spring support plate;

a fastener for connecting a prosthetic ankle, said proximal end of said at least one toe spring, and said at least one toe spring support plate to said at least one heel spring;

a fastener for connecting said heel portion of said foot plate and said at least one heel attachment plate to said at least one heel spring; and

a prosthetic ankle adapted for mounting to said prosthetic foot;

wherein, when connected to said prosthetic foot, the position of said prosthetic ankle will approximate the position of a typical human ankle.

25. The low profile prosthetic assembly foot of claim 24, wherein a pair of toe springs are connected between said toe portion of said foot plate and said at least one heel spring.

26. The low profile prosthetic foot assembly of claim 24, wherein a pair of heel springs are connected between said heel portion of said foot plate and said proximal end of said at least one toe spring.

27. The low profile prosthetic foot assembly of claim 24, wherein said toe spring support plate includes a stop that limits the differential movement of a side of said at least one toe spring that is subjected to compression during bending thereof.

28. The low profile prosthetic foot assembly of claim 24, wherein said at least one heel spring is a pneumatic or hydraulic shock absorber.

29. The low profile prosthetic foot assembly of claim 24, wherein said at least one heel spring is a helical compression spring.

30. The low profile prosthetic foot assembly of claim 24, wherein said at least one heel spring is made from an elastomeric material.

31. The low profile prosthetic foot assembly of claim 30, wherein said at least one heel spring has at least one recess or cavity located therein, said recess or cavity affecting the compressive resistance of said at least one heel spring.

32. The low profile prosthetic foot assembly of claim 31, wherein a secondary heel spring element is located in said recess or cavity, said secondary heel spring element having a compressive modulus that differs from the compressive modulus of the elastomeric material forming said at least one heel spring.

33. The low profile prosthetic foot assembly of claim 30, further comprising a threaded fastener embedded in one, or both, ends of said at least one heel spring.

34. The low profile prosthetic foot assembly of claim 30, further comprising a fiber reinforcement material embedded in said elastomeric material.

35. The low profile prosthetic foot assembly of claim 30, further comprising at least one auxiliary toe spring disposed below said at least one toe spring.

36. The low profile prosthetic foot assembly of claim 35, further comprising a spacer plate disposed between said at least one toe spring and said at least one auxiliary toe spring.

37. The low profile prosthetic foot assembly of claim 36, further comprising a recess in said spacer plate for receiving a proximal portion of said at least one toe spring.

38. The low profile prosthetic foot assembly of claim 37, wherein said recess acts to limit the differential movement of a side of said at least one toe spring that is subjected to compression during bending thereof.

39. The low profile prosthetic foot assembly of claim 36, further comprising a stop on said spacer plate that limits the differential movement of a side of said at least one toe spring that is subjected to compression during bending thereof.

40. The low profile prosthetic foot assembly of claim 24, wherein said at least one toe spring is secured to said at least one heel spring by passing at least one fastener through a prosthetic ankle, through said at least one toe spring, and into said at least one heel spring.

41. The low profile prosthetic foot assembly of claim 24, wherein said distal end of said at least one toe spring is connected to said foot plate by a toe spring clamp assembly that is molded to said foot plate.

42. A low profile prosthetic foot assembly, comprising:

a foot plate having a heel portion and a toe portion spaced along the length thereof;

at least one primary toe spring having a distal end connected to said toe portion of said foot plate, said at least one toe spring extending upward at an angle to a proximal end located above said heel portion of said foot plate;

at least one auxiliary toe spring having a distal end and a proximal end and disposed beneath said at least one primary toe spring;

a spacer plate residing between proximal ends of said at least one primary toe spring and said at least one auxiliary toe spring;

at least one heel spring, said at least one heel spring constructed from an elastomeric material and having a recess or cavity for receiving a secondary heel spring element made from a material having a compressive modulus differing from that of said elastomeric material, a rounded end of said heel spring connected to said foot plate and an opposite, flat end, of said heel spring abutting said at least one auxiliary toe spring;

a fastener for connecting an articulating ankle, said proximal end of said at least one toe spring, said spacer plate, and said proximal end of said at least one auxiliary toe spring to said at least one heel spring;

a fastener for connecting said heel portion of said foot plate to said at least one heel spring; and

a prosthetic ankle adapted for mounting to said prosthetic foot;

wherein, when connected to said prosthetic foot, the position of said prosthetic ankle will approximate the position of a typical human ankle.

43. The low profile prosthetic foot assembly of claim 42, further comprising a recess in said spacer plate for receiving a proximal portion of said at least one toe spring.

44. The low profile prosthetic foot assembly of claim 43, wherein said recess acts to limit the differential movement of a side of said at least one toe spring that is subjected to compression during bending thereof.

45. The low profile prosthetic foot assembly of claim 42, further comprising a stop on said spacer plate that limits the differential movement of a side of said at least one toe spring that is subjected to compression during bending thereof.

46. The low profile prosthetic foot assembly of claim 42, further comprising a stop located near said distal end of said at least one auxiliary toe spring, said stop limiting total bending of said toe springs by contacting said foot plate.

47. The low profile prosthetic foot assembly of claim 46, wherein said stop also prevents contact between said distal end of said at least one auxiliary toe spring and said at least one primary toe spring.

48. The low profile prosthetic foot assembly of claim 42, further comprising a fiber reinforcement material embedded in said heel spring.

49. A low profile prosthetic foot assembly, comprising:

a foot plate having a heel portion and a toe portion spaced along the length thereof;

at least one toe spring having a distal end connected to said toe portion of said foot plate, said at least one toe spring extending upward at an angle to a proximal end located above said heel portion of said foot plate;

a toe spring clamp assembly molded to said toe portion of said foot plate and connecting said at least one toe spring thereto;

at least one elastomeric heel spring having one end thereof molded to at least a portion of said proximal end of said at least one toe spring, and an opposite end thereof molded to said heel portion of said foot plate; and

a prosthetic ankle adapted for mounting to said prosthetic foot;

wherein, when connected to said prosthetic foot, the position of said prosthetic ankle will approximate the position of a typical human ankle.

50. The low profile prosthetic foot assembly of claim 49, wherein said at least one elastomeric heel spring has at least one recess or cavity located therein, said recess or cavity affecting the compressive resistance of said at least one heel spring.

51. The low profile prosthetic foot assembly of claim 50, wherein a secondary heel spring element is located in said recess or cavity, said secondary heel spring element having a compressive modulus that differs from the compressive modulus of the elastomeric material forming said at least one heel spring.

52. The low profile prosthetic foot assembly of claim 49, further comprising a fiber reinforcement material embedded in said at least one elastomeric heel spring.

53. The low profile prosthetic foot assembly of claim 50, further comprising at least one auxiliary toe spring disposed below said at least one toe spring and connected to said at least one elastomeric heel spring.

54. The low profile prosthetic foot assembly of claim 53, further comprising a spacer plate disposed between said at least one toe spring and said at least one auxiliary toe spring.

55. A low profile prosthetic foot, comprising:

a foot plate having a heel portion and a toe portion spaced along the length thereof;

at least one primary toe spring having a distal end connected to said toe portion of said foot plate and a proximal end residing some distance above said heel portion of said foot plate;

at least one auxiliary toe spring disposed below said at least one toe spring; and

at least one heel spring residing between said heel portion of said foot plate and said proximal end of said at least one primary toe spring.

56. The low profile prosthetic foot of claim 55, wherein a pair of primary toe springs are used.

58. The low profile prosthetic foot of claim 55, further comprising a heel attachment plate disposed between said foot plate and said at least one heel spring.

59. The low profile prosthetic foot of claim 55, further comprising a spacer plate disposed between said at least one primary toe spring and said at least one auxiliary toe spring.

60. The low profile prosthetic foot of claim 59, wherein said spacer plate includes a stop that limits the differential movement of a side of said at least one toe spring that is subjected to compression during bending thereof.

61. The low profile prosthetic foot of claim 55, wherein said at least one heel spring is a pneumatic or hydraulic shock absorber.

62. The low profile prosthetic foot of claim 55, wherein said at least one heel spring is a helical compression spring.

63. The low profile prosthetic foot of claim 55, wherein said at least one heel spring is made from an elastomeric material.

64. The low profile prosthetic foot of claim 63, wherein said at least one heel spring has at least one recess or cavity located therein, said recess or cavity affecting the compressive resistance of said at least one heel spring.

65. The low profile prosthetic foot of claim 63, wherein a secondary heel spring element is located in said recess or cavity, said secondary heel spring element having a compressive modulus that differs from the compressive modulus of the elastomeric material forming said at least one heel spring.

66. The low profile prosthetic foot of claim 63, wherein said at least one heel spring is a U-shaped element, a rounded end of which is adapted for connection to said foot plate.

67. The low profile prosthetic foot of claim 66, further comprising a threaded fastener embedded in one, or both, ends of said at least one heel spring.

68. The low profile prosthetic foot of claim 63, wherein one end of said heel spring is molded to said foot plate.

69. The low profile prosthetic foot of claim 63, wherein one end of said heel spring is molded to a proximal end of said at least one auxiliary toe spring.

70. The low profile prosthetic foot of claim 63, further comprising a fiber reinforcement material embedded in said elastomeric material.

71. The low profile prosthetic foot of claim 55, further comprising a recess in said at least one auxiliary toe spring for receiving one end of said at least one heel spring.

72. The low profile prosthetic foot of claim 55, wherein said at least one primary toe spring is secured to said at least one heel spring by passing at least one fastener through a prosthetic ankle, through said at least one primary and said at least one auxiliary toe spring, and into said at least one heel spring.

73. The low profile prosthetic foot of claim 55, wherein said distal end of said at least one primary toe spring is connected to said foot plate by a toe spring clamp assembly that is molded to said foot plate.