Sensing systems and methods for monitoring gait dynamics

• US 7,794,505 B2
• Filed: 05/08/2006
• Issued: 09/14/2010
• Est. Priority Date: 02/02/2005
• Status: Active Grant

• Current Assignee: Ossur hf
• Original Assignee: Ossur hf
• Inventors: Oddsson, Magn s, Clausen, Arinbjorn V.
• Primary Examiner(s): Sweet; Thomas J
• Assistant Examiner(s): Woznicki; Jacqueline
• Application Number:
  US11/429,696
• Publication Number:
  US 20060206214A1
• Time in Patent Office: 1,590 Days
• Field of Search: 623/50
• US Class Current: 623/24
• CPC Class Codes: A61B 5/1038 Measuring plantar pressure during gait
• CPC Class Codes: A61B 5/112 Gait analysis
• CPC Class Codes: A61F 2/66 Feet; Ankle joints
• CPC Class Codes: A61F 2/70 electrical
• CPC Class Codes: A61F 2/76 Means for assembling, fitting or testing prostheses, e.g. for measuring or balancing, e.g. alignment means
• CPC Class Codes: A61F 2002/5055 Reinforcing prostheses by embedding particles or fibres during moulding or dipping, e.g. carbon fibre composites
• CPC Class Codes: A61F 2002/6614 Feet
• CPC Class Codes: A61F 2002/6621 Toes
• CPC Class Codes: A61F 2002/6642 Heels
• CPC Class Codes: A61F 2002/6657 having a plate-like or strip-like spring element, e.g. an energy-storing cantilever spring keel
• CPC Class Codes: A61F 2002/6671 C-shaped
• CPC Class Codes: A61F 2002/6685 S-shaped
• CPC Class Codes: A61F 2002/704 computer-controlled, e.g. robotic control
• CPC Class Codes: A61F 2002/705 Electromagnetic data transfer
• 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
• CPC Class Codes: A61F 2002/769 Displaying measured values
• CPC Class Codes: A61F 2002/7695 Means for testing non-implantable prostheses
• CPC Class Codes: A61F 2005/0188 having pressure sensors

Abstract

Systems and method for monitoring gait dynamics are disclosed. The performance of an orthotic or prosthetic device or other device associated with a limb may be measured based on the resistance of a bending sensor. Data from the sensors is gathered or processed, particularly for purposes of alignment, safety, failure, usage, selection, and artificial proprioception. Information relating to the device may be outputted visually or auditorily to an individual.

Claims

1. A method of providing information to a user of a device associated with a limb, comprising:

providing a prosthetic device associated with a limb of a user, wherein the prosthetic device comprises a flexible foot member configured to bend during locomotion by the user, the prosthetic device having at least one flexible sensor associated therewith, the at least one flexible sensor comprising an elongated strip adhered to a top surface of the flexible foot member and extending in an anterior/posterior direction along both sides of a bending axis of the flexible foot member;

measuring with said at least one flexible sensor resistance corresponding to bending of said flexible foot member while in use by the user, wherein a bending of the at least one flexible sensor corresponds to a bending of the flexible foot member; and

identifying a state in a gait of the user based on an output of the at least one flexible sensor that corresponds with said measuring of the resistance corresponding to said bending of the flexible foot member; and

outputting information relating to the state in the gait of the user.

2. The method of claim 1, wherein said outputting is performed through headphones worn by the user.

3. The method of claim 1, wherein said outputting is performed through a speaker located on the prosthetic device.

4. The method of claim 3, further comprising varying a pitch or volume of a sound emitted by the speaker based on the state in the gait of the user.

5. The method of claim 1, wherein the state is selected from a group consisting of heel strike and toe load.

6. The method of claim 1, wherein the output of the at least one flexible sensor comprises a resistance output.

7. The method of claim 1, further comprising detecting from said information a change in the state of the gait of the user.

8. The method of claim 7, further comprising dynamically adjusting the prosthetic device during the gait of the user based on the detected change in the state of the gait of the user.

9. The method of claim 8, wherein said dynamically adjusting is performed automatically in real-time.

10. The method of claim 9, wherein the flexible sensor comprises a resistive strip having a length to width ratio of at least 5:

1.

11. A method of providing information regarding a prosthetic foot, comprising:

providing a prosthetic foot having an elongated foot member and at least one bending force sensor associated therewith, the bending force sensor comprising an elongated strip adhered to a top surface of the elongated foot member and extending in an anterior/posterior direction along both sides of a bending axis of the elongated foot member;

measuring with said bending force sensor a resistance corresponding to said bending of said elongated foot member while in use by an individual,

wherein a bending of the bending force sensor corresponds to a bending of the elongated foot member;

receiving from the bending force sensor an output correlated to said resistance corresponding to said bending of the elongated foot member;

processing said output to identify a state change in a gait of the individual;

and outputting a feedback signal corresponding to the state change in the gait of the individual.

12. The method of claim 11, wherein the feedback is outputted through headphones.

13. The method of claim 11, further comprising automatically aligning the prosthetic foot in real-time based on the feedback signal outputted.

14. The method of claim 11, further comprising dynamically adjusting the prosthetic foot during the gait of the individual based on said feedback signal.

15. The method of claim 14, wherein said receiving comprises detecting a change in a resistance of the bending force sensor.

16. A system for measuring performance of a prosthetic foot, comprising:

a prosthetic foot device comprising a flexible foot member configured to bend during locomotion by a user;

a flexible force sensor positioned on an upper surface of the foot member, the flexible force sensor comprising an elongated resistive strip extending in an anterior/posterior direction along the upper surface of the foot member and configured to bend with the foot member during use, the flexible force sensor being further configured to measure changes in bending forces of the foot member during locomotion by the user;

a processor in communication with the flexible force sensor and configured to receive an output from the flexible force sensor indicative of the changes in the bending forces; and

a user interface in communication with the processor and configured to provide feedback information relating to the changes in the bending forces measured by the flexible force sensor.

17. The system of claim 16, wherein the user interface comprises headphones to be worn by the user.

18. The system of claim 16, further comprising a memory that stores a history of the changes in the bending forces measured by the flexible force sensor.

19. The system of claim 18, wherein the memory is attached to the prosthetic foot device.

20. The system of claim 16, wherein the elongated resistive strip comprises a length to width ratio of greater than about 5:

1.

21. The system of claim 16, wherein the processor is further configured to identify states in a gait of the user based on the output from the flexible force sensor.

22. A system for providing artificial proprioceptive feedback from a device associated with a limb, comprising:

a prosthetic device associated with a lower limb of a user, the prosthetic device comprising a flexible foot portion configured to bend during locomotion by the user;

an elongated bending force sensor affixed on an upper surface of the flexible foot portion of the prosthetic device and extending over both sides of a bending axis of the flexible foot portion, the bending force sensor configured to bend with the flexible foot portion during locomotion, the flexible force sensor being further configured to measure changes in bending forces of the flexible foot portion during locomotion device;

means for communicating feedback corresponding to the changes in bending forces of the flexible foot portion wherein the feedback provides artificial proprioception to the user of the prosthetic device.

23. The system of claim 22, wherein the bending force sensor comprises a variable printed resistive strip.