EQUILIBRIUM-POINT PROSTHETIC AND ORTHOTIC ANKLE-FOOT SYSTEMS, DEVICES, AND METHODS OF USE

• US 20100185301A1
• Filed: 10/17/2007
• Published: 07/22/2010
• Est. Priority Date: 10/17/2006
• Status: Active Grant

• Current Assignee: Northwestern University
• Original Assignee: Rehabilitation Institute of Chicago (Tenet Healthcare Corporation)
• Inventors: Williams, Ryan, Ruhe, Brian, Childress, Dudley S., Hansen, Andrew H, Gard, Steven A.
• Granted Patent: US 8,597,369 B2
• Time in Patent Office: Days
• US Class Current: 623/47
• CPC Class Codes: A61F 2/6607 Ankle joints
• CPC Class Codes: A61F 2/70 electrical
• CPC Class Codes: A61F 2002/5003 having damping means, e.g. shock absorbers for implantable joints A61F2002/30563
• CPC Class Codes: A61F 2002/5009 having two or more elastomeric blocks
• CPC Class Codes: A61F 2002/5036 self-adjustable, e.g. self-learning
• 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 2002/6818 for braking
• CPC Class Codes: A61F 2002/6845 Clutches
• CPC Class Codes: A61F 2002/6854 for locking or unlocking a joint
• CPC Class Codes: A61F 2002/701 operated by electrically controlled means, e.g. solenoids or torque motors
• CPC Class Codes: A61F 2002/704 computer-controlled, e.g. robotic control
• CPC Class Codes: A61F 2002/7625 for measuring angular position
• CPC Class Codes: A61F 2002/7635 for measuring force, pressure or mechanical tension
• CPC Class Codes: A61F 2002/7645 for measuring torque, e.g. hinge or turning moment, moment of force

Abstract

The present invention relates to a system for use in rehabilitation and/or physical therapy for the treatment of injury or disease. The system can enable an amputee to proceed over any surface without overbalancing. In particular the system is self-adapting to adjust the torque moment depending upon the motion, the extent of inclination, and the surface topography.

Claims

1. A self-adapting prosthetic system for a user to emulate normal gait, the self-adapting prosthetic system comprising an ankle member, the ankle member comprising a reversible engagement means, a first torsion means, and a joint, and wherein in use, a torsion curve plot of ankle moment against ankle dorsiflexion angle of the prosthetic system during a gait cycle comprises at least one transition point, wherein the reversible engagement means is operatively connected to the first torsion means, wherein the first torsion means is operatively connected to the joint, and wherein the joint is operatively connected to the engagement means.

2. The self-adapting prosthetic system of claim 1 wherein the system is used by a user to proceed over a surface without compromising the user'"'"'s balance wherein the surface comprises a plurality of grades.

3. The self-adapting prosthetic system of claim 2 wherein the torsion curve plot comprises a plurality of transition points.

4. The self-adapting prosthetic system of claim 1 further comprising at least one second torsion means operatively connected to the ankle member and the joint.

5. The self-adapting prosthetic system of claim 4 wherein the second torsion means comprises a pair of neutralizing torsion means.

6. The self-adapting prosthetic system of claim 1 wherein the transition point of the torsion curve plot is at a negative torque moment.

7. The self-adapting prosthetic system of claim 1 wherein the transition point of the torsion curve plot is at a negative ankle dorsiflexion angle.

8. The self-adapting prosthetic system of claim 1 wherein the transition point of the torsion curve plot is at a positive torque moment.

9. The self-adapting prosthetic system of claim 1 wherein the transition point of the torsion curve plot is at a positive ankle dorsiflexion angle.

10. The self-adapting prosthetic system of claim 1 wherein the engagement means is selected from the group consisting of a lock, a piston, a ratchet, a clutch, a wrap spring clutch, and a brake.

11. The self-adapting prosthetic system of claim 1 wherein the torsion means is selected from the group consisting of a spring, a tunable spring, a clockwork spring, a piston, and a damper.

12. The self-adapting prosthetic system of claim 1 further comprising a foot plate.

13. The self-adapting prosthetic system of claim 1 further comprising a shin member.

14. The self-adapting prosthetic system of claim 1 further comprising a microprocessor.

15. The self-adapting prosthetic system of claim 1 further comprising a motor.

16. The self-adapting prosthetic system of claim 1 further comprising an actuator.

17. The self-adapting prosthetic system of claim 1 further comprising a potentiometer.

18. The self-adapting prosthetic system of claim 1 wherein the system automatically adapts to different surface conditions.

19. The self-adapting prosthetic system of claim 1 wherein the equilibrium point is set upon each step and is dependent upon the slope.

20. The self-adapting prosthetic system of claim 1 wherein the self-adapting prosthetic system comprises a composition selected from the group consisting of stainless steel, copper, aluminum, titanium, metal matrix composite, metal alloy, NITINOL, DELRIN (acetal), acrylonitrile butadiene styrene (ABS), nylon, polypropylene, polybromate, polycarbonate, glycolised polyethylene terephthalate (PETg) copolyester, olytetrafluorethylene (PTFE), ePTFE, polypropylene, a polymer, glass fiber-resin composites, and carbon fiber resin composites.

61. A method for providing normal gait in an amputee, the amputee having lost a lower limb extremity, the method comprising (i) providing the self-adapting prosthetic system of claim 1;

(ii) attaching the self-adapting prosthetic system to the lower limb of the amputee;

(iii) allowing the amputee to ambulate for at least one gait cycle, the gait cycle comprising at least two phases of dorsiflexion over time, whereby a load applied during a first phase of dorsiflexion results in the engagement means engaging and damping movement of the engagement means, wherein during the first phase when the ankle dorsiflexion angle is at an ankle angle minimum dorsiflexion the engagement means engages and dampens fully, and wherein during a second phase of dorsiflexion when the ankle dorsiflexion angle is at another ankle angle minimum dorsiflexion the engagement means disengages and releases fully, the method resulting in providing normal gait to the amputee.

62. The method of claim 61 wherein the gait cycle comprises at least three phases of ankle flection.

63. The method of claim 61 wherein the engagement and dampening of the engagement means coincides with a first transition point of the torsion curve plot.

64. The method of claim 61 wherein the disengagement and release of the engagement means coincides with a second transition point of the torsion curve plot.

65. The method of claim 61 further comprising a step of determining an equilibrium point, wherein an equilibrium point of the torsion curve plot is at a negative dorsiflexion angle.

66. The method of claim 61 further comprising a step of determining an equilibrium point, wherein an equilibrium point of the torsion curve plot is at a positive dorsiflexion angle.

73. The method of claim 61 wherein the equilibrium point β

of the torsion curve plot is calculated using the equation

T_ts=k_ts(θ

−

β

),

where T_ts=torque due to triceps surae spring(s);

q=ankle dorsiflexion angle;

b=ankle angle at the trigger time; and

k_ts is the impedance factor.

74. The method of claim 61 wherein the equilibrium point ζ

of the torsion curve plot is calculated using the equation

T_ns=k_ns(θ

−

β

),

where T_ts=torque due to neutralizing spring(s);

q=ankle dorsiflexion angle;

ζ

=ankle dorsiflexion bias; and

k_ns is the impedance factor.

21. A self-adapting prosthetic system for a user to emulate normal gait, the prosthetic system comprising an ankle member, the ankle member comprising a reversible engagement means, torsion means, and a joint, and wherein in use, a torsion curve plot of ankle moment against ankle dorsiflexion angle of the prosthetic system during a gait cycle comprises at least two equilibrium points, wherein the reversible engagement means is operatively connected to the first torsion means, wherein the first torsion means is operatively connected to the joint, and wherein the joint is operatively connected to the engagement means.

22. The self-adapting prosthetic system of claim 21 wherein the system is used by a user to proceed over a surface without overbalancing wherein the surface comprises a plurality of grades.

23. The self-adapting prosthetic system of claim 22 wherein the torsion curve plot comprises a plurality of transition points.

24. The self-adapting prosthetic system of claim 21 further comprising at least one second torsion means.

25. The self-adapting prosthetic system of claim 24 wherein the second torsion means comprises a pair of neutralizing torsion means.

26. The self-adapting prosthetic system of claim 21 wherein the transition point of the torsion curve plot is at a negative torque moment.

27. The self-adapting prosthetic system of claim 21 wherein the transition point of the torsion curve plot is at a negative ankle dorsiflexion angle.

28. The self-adapting prosthetic system of claim 21 wherein the transition point of the torsion curve plot is at a positive torque moment.

29. The self-adapting prosthetic system of claim 21 wherein the transition point of the torsion curve plot is at a positive ankle dorsiflexion angle.

30. The self-adapting prosthetic system of claim 21 wherein the engagement means is selected from the group consisting of a lock, a piston, a ratchet, a clutch, a wrap spring clutch, and a brake.

31. The self-adapting prosthetic system of claim 21 wherein the torsion means is selected from the group consisting of a spring, a tunable spring, a clockwork spring, a piston, and a damper.

32. The self-adapting prosthetic system of claim 21 further comprising a foot plate.

33. The self-adapting prosthetic system of claim 21 further comprising a shin member.

34. The self-adapting prosthetic system of claim 21 further comprising a microprocessor.

35. The self-adapting prosthetic system of claim 21 further comprising a motor.

36. The self-adapting prosthetic system of claim 21 further comprising an actuator.

37. The self-adapting prosthetic system of claim 21 further comprising a potentiometer.

38. The self-adapting prosthetic system of claim 21 wherein the system automatically adapts to different surface conditions.

39. The self-adapting prosthetic system of claim 21 wherein the equilibrium point is set upon each step and is dependent upon the slope.

40. The self-adapting prosthetic system of claim 21 wherein the self-adapting prosthetic system comprises a composition selected from the group consisting of stainless steel, copper, aluminum, titanium, metal matrix composite, metal alloy, NITINOL, DELRIN (acetal), acrylonitrile butadiene styrene (ABS), nylon, polypropylene, polybromate, polycarbonate, glycolised polyethylene terephthalate (PETg) copolyester, olytetrafluorethylene (PTFE), ePTFE, polypropylene, a polymer, glass fiber-resin composites, and carbon fiber resin composites.

41. A self-adapting prosthetic ankle-foot device for a user to emulate normal gait, the self-adapting prosthetic ankle-foot device comprising an ankle unit, the ankle unit comprising a reversible engagement means, a first torsion means, and a joint, and wherein in use, a torsion curve plot of ankle moment against ankle dorsiflexion angle of the self-adapting prosthetic ankle-foot device during a gait cycle comprises at least one transition point, wherein the reversible engagement means is operatively connected to the first torsion means, wherein the first torsion means is operatively connected to the joint, and wherein the joint is operatively connected to the engagement means.

43. The self-adapting prosthetic device of claim 41 wherein the system is used by a user to proceed over a surface without overbalancing wherein the surface comprises a plurality of grades.

44. The self-adapting prosthetic system of claim 43 wherein the torsion curve plot comprises a plurality of transition points.

45. The self-adapting prosthetic system claim 41 further comprising at least one second torsion means.

46. The self-adapting prosthetic system of claim 45 wherein the second torsion means comprises a pair of neutralizing torsion means.

47. The self-adapting prosthetic system of claim 41 wherein the transition point of the torsion curve plot is at a negative torque moment.

48. The self-adapting prosthetic system of claim 41 wherein the transition point of the torsion curve plot is at a negative ankle dorsiflexion angle.

49. The self-adapting prosthetic system of claim 41 wherein the transition point of the torsion curve plot is at a positive torque moment.

50. The self-adapting prosthetic system of claim 41 wherein the transition point of the torsion curve plot is at a positive ankle dorsiflexion angle.

51. The self-adapting prosthetic system of claim 41 wherein the engagement means is selected from the group consisting of a lock, a piston, a ratchet, a clutch, a wrap spring clutch, and a brake.

52. The self-adapting prosthetic system of claim 41 wherein the torsion means is selected from the group consisting of a spring, a tunable spring, a clockwork spring, a piston, and a damper.

53. The self-adapting prosthetic system of claim 41 further comprising a foot plate.

54. The self-adapting prosthetic system of claim 41 further comprising a shin member.

55. The self-adapting prosthetic system of claim 41 further comprising a microprocessor.

56. The self-adapting prosthetic system of claim 41 further comprising a motor.

57. The self-adapting prosthetic system of claim 41 further comprising an actuator.

58. The self-adapting prosthetic system of claim 41 further comprising a potentiometer.

59. The self-adapting prosthetic system of claim 41 wherein the system automatically adapts to different surface conditions.

60. The self-adapting prosthetic system of claim 41 wherein the equilibrium point is set upon each step and is dependent upon the slope.

67. A method for providing normal gait in an amputee, the amputee having lost a lower limb extremity, the method comprising (i) providing the self-adapting prosthetic ankle-foot device of claim 41;

(ii) attaching the self-adapting prosthetic ankle-foot device to the lower limb of the amputee;

(iii) allowing the amputee to ambulate for at least one gait cycle, the gait cycle comprising at least two phases of dorsiflexion over time, whereby a load applied during a first phase of dorsiflexion results in the engagement means engaging and damping movement of the engagement means, wherein during the first phase when the velocity of ankle dorsiflexion angle change equals zero the engagement means engages and dampens fully, and wherein during a second phase of dorsiflexion when the velocity of ankle dorsiflexion angle change equals zero the engagement means disengages and releases fully, the method resulting in providing normal gait to the amputee.

68. The method of claim 67 wherein the gait cycle comprises at least three phases of ankle flection.

69. The method of claim 67 wherein the engagement and dampening of the engagement means coincides with a first transition point of the torsion curve plot.

70. The method of claim 67 wherein the disengagement and release of the engagement means coincides with a second transition point of the torsion curve plot.

71. The method of claim 67 further comprising a step of determining an equilibrium point, wherein the equilibrium point of the torsion curve plot is at a negative dorsiflexion angle.

72. The method of claim 67 further comprising a step of determining an equilibrium point, wherein the equilibrium point of the torsion curve plot is at a positive dorsiflexion angle.

75. The method of claim 67 wherein the equilibrium point β

of the torsion curve plot is calculated using the equation

T_ts=k_ts(θ

−

β

),

where T_ts=torque due to triceps surae spring(s);

q=ankle dorsiflexion angle;

b=ankle angle at the trigger time; and

k_ts is the impedance factor.

76. The method of claim 67 wherein the equilibrium point ζ

of the torsion curve plot is calculated using the equation

T_ns=k_ns(θ

−

ζ

),

where T_ts=torque due to neutralizing spring(s);

q=ankle dorsiflexion angle;

ζ

=ankle dorsiflexion bias; and

k_ns is the impedance factor.

42. A self-adapting prosthetic ankle-foot device for a user to emulate normal gait, the self-adapting prosthetic ankle-foot device comprising an ankle unit, the ankle unit comprising a reversible engagement means, torsion means, and a joint, and wherein in use, a torsion curve plot of ankle moment against ankle dorsiflexion angle of the self-adapting prosthetic ankle-foot device during a gait cycle comprises at least two equilibrium points, wherein the reversible engagement means is operatively connected to the first torsion means, wherein the first torsion means is operatively connected to the joint, and wherein the joint is operatively connected to the engagement means.