DEVICE, METHOD AND STIMULUS UNIT FOR TESTING NEUROMUSCULAR FUNCTION

• US 20070129771A1
• Filed: 11/07/2006
• Published: 06/07/2007
• Est. Priority Date: 04/20/2005
• Status: Abandoned Application

• Current Assignee: Natus Medical Incorporated
• Original Assignee: Natus Medical Incorporated
• Inventors: Kurtz, Ronald, Ramirez Rodriguez, Daniel, Mumford, John
• Application Number:
  US11/557,390
• Publication Number:
  US 20070129771A1
• Time in Patent Office: Days
• US Class Current: 607/48
• CPC Class Codes: A61B 5/24 Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
• CPC Class Codes: A61B 5/4041 Evaluating nerves condition

Abstract

Embodiments relate generally to devices, methods and stimulus units for use in measuring neuromuscular function. Certain embodiments relate to a device for use in measuring at least one of nerve and muscle function, comprising: a substrate locatable on a body part, the substrate comprising a base portion, a limb portion and an intermediate portion located intermediate the base portion and the limb portion; first, second and third electrode pairs respectively located on the base, intermediate and limb portions; and wherein at least one of the first, second and third electrode pairs is usable as stimulation electrodes for providing a stimulus to the body part and at least another of the first, second and third electrodes is usable as sensing electrodes for sensing an electrical potential in the body part in response to the stimulus.

Claims

1. A device for use in measuring at least one of nerve and muscle function, comprising:

a substrate locatable on a body part, the substrate comprising a base portion, a limb portion and an intermediate portion located intermediate the base portion and the limb portion;

first, second and third electrode pairs respectively located on the base, intermediate and limb portions; and

wherein at least one of the first, second and third electrode pairs is usable as stimulation electrodes for providing a stimulus to the body part and at least another of the first, second and third electrodes is usable as sensing electrodes for sensing an electrical potential in the body part in response to the stimulus.

2. The device of claim 1, further comprising a distance measurement member coupled to one of the base portion, intermediate portion and limb portion for use in indicating separation of the stimulation electrodes and the sensing electrodes.

3. The device of claim 2, wherein the distance measurement member comprises indicia for indicating separation of the stimulation electrodes and the sensing electrodes.

4. The device of claim 3, wherein the indicia is selected from the group consisting of:

magnetic indicia;

electrical indicia;

optical indicia;

electromechanical indicia; and

mechanical indicia.

5. The device of claim 2, wherein the distance measurement member comprises an elongate strip.

6. The device of claim 2, wherein the distance measurement member is coupled to the limb portion at a fixed location relative to the third electrode pair.

7. The device of claim 1, wherein the substrate is flexible to at least partly conform to a shape of the body part when positioned over the body part.

8. The device of claim 1, wherein the body part comprises a hand and wrist.

9. The device of claim 1, wherein the stimulation and sensing electrodes each have a layer of conductive gel disposed on the stimulation and sensing electrodes for contact with the body part.

10. The device of claim 9, wherein the stimulation and sensing electrodes are covered by a protective material, and wherein, in use of the device, the protective material is removed before placement of the stimulation and sensing electrodes on the body part.

11. The device of claim 1, wherein the base portion and intermediate portion are separated by a fixed distance and the separation of the base portion and the limb portion is adjustable.

12. The device of claim 11, wherein a cathode of the first electrode pair is separated from a cathode of the second electrode pair by about 8cm.

13. The device of claim 3, further comprising a scanner for reading the indicia on the distance measurement member.

14. The device of claim 2, wherein one of the substrate and the distance measurement member comprises a unique identifier of the device.

15. The device of claim 14, wherein the unique identifier is encoded on one of the distance measurement member and the substrate.

16. The device of claim 15, wherein the unique identifier is machine-readable.

17. The device of claim 1, further comprising a coupling unit for electrically coupling a current stimulation controller to the stimulating electrodes.

18. The device of claim 17, wherein the coupling unit is supportingly connectable to the base portion of the substrate.

19. The device of claim 18, wherein the coupling unit is connectable to the base portion by conductive connectors.

20. The device of claim 17, wherein the coupling unit comprises a temperature sensor.

21. The device of claim 20, wherein the temperature sensor is an infrared optical sensor.

22. The device of claim 17, wherein the substrate comprises flexible conductors extending through the limb portion for carrying current from the sensing electrodes to the coupling unit.

23. The device of claim 22, wherein the device further comprises a connector limb having a connector on an end of the connector limb, the connector being connectable to the coupling unit.

24. The device of claim 23, wherein the connector on the connector limb is an output connector for providing at least one output of the sensing electrodes.

25. The device of claim 19, wherein the conductive connectors are coupled to one of the first, second and third electrode pairs.

26. The device of claim 1, wherein the limb portion is a first limb portion and the substrate comprises a second limb portion comprising at least one sensing electrode.

27. The device of claim 26, wherein the substrate is shaped so that each limb portion extends to a different designated area of the body part when the substrate is positioned for use on the body part.

28. The device of claim 27, wherein the designated area is selected from the group consisting of:

thenar, hypothenar, first digit, second digit and third digit.

29. The device of claim 27, wherein the second limb portion extends to a thenar area of the body part and the second limb comprises a thenar sensing electrode for sensing an evoked CMAP response, wherein the evoked CMAP response can be sensed using the thenar sensing electrode and one other electrode.

30. The device of claim 29, wherein the other electrode is an electrode of the third electrode pair.

31. The device of claim 17, wherein the coupling unit comprises a connector for coupling to conductors extending along the substrate.

32. The device of claim 17, wherein the coupling unit comprises a distance measurement sensor for cooperating with a distance measurement member to indicate the separation of the sensing electrodes and the stimulation electrodes.

33. The device of claim 32, wherein the distance measurement member comprises an elongate strip and the coupling unit has an opening for receiving the elongate strip.

34. The device of claim 33, wherein the distance measurement sensor is housed within the coupling unit and positioned to cooperate with the distance measurement member to indicate the separation when the elongate strip is received in the opening.

35. The device of claim 34, wherein the opening extends through the coupling unit and at least part of the elongate strip may be drawn through the opening.

36. The device of claim 1, wherein the limb portion comprises a plurality of branches, each branch comprising an electrode pair.

37. The device of claim 1, wherein the limb portion comprises an extensible portion intermediate the intermediate portion and a distal end of the limb portion.

38. The device of claim 1, wherein the substrate comprises an extensible portion intermediate the base portion and the intermediate portion.

39. The device of claim 37, wherein the extensible portion comprises at least one loop formed in the limb portion.

40. The device of claim 1, further comprising distance measurement means fixed relative to the substrate for measuring separation of the stimulation electrodes and the sensing electrodes.

41. The device of claim 1, wherein the first and second electrode pairs are usable as stimulation electrodes and the third electrode pair is usable as sensing electrodes.

42. The device of claim 1, wherein the first and second electrode pairs are usable as sensing electrodes and the third electrode pair is usable as stimulation electrodes.

43. The device of claim 1, wherein the second electrode pair is usable as stimulation electrodes and the first and third electrode pairs are usable as sensing electrodes.

44. The device of claim 1, wherein the first electrode pair is usable as stimulation electrodes and the second and third electrode pairs are usable as sensing electrodes.

45. The device of claim 1, wherein the limb is attachable to one of the first, second and third digits of a hand.

46. The device of claim 26, wherein the first and second limb portions are flexibly movable relative to the base portion to accommodate differently sized body parts.

47. The device of claim 26, wherein the second limb portion is disposed on the substrate adjacent the intermediate portion and the second limb portion is flexibly movable relative to the intermediate portion.

48. The device of claim 7, wherein the substrate is shaped so that, when the substrate is located in use on the body part, the base portion at least partly overlies the wrist, the intermediate portion at least partly overlies a palm of the hand and the limb portion at least partly overlies a finger of the hand.

49. The device of claim 48, wherein the intermediate portion at least partly overlies an area of the palm through which the median nerve passes.

50. Use of the device of claim 1 for testing for carpal tunnel syndrome.

51. A device for use in measuring at least one of nerve and muscle function in an arm, comprising:

a wrist portion locatable on a wrist;

a palm portion locatable on a palm and coupled to the wrist portion;

a finger portion locatable on a finger and coupled to one of the wrist portion and the palm portion;

first, second and third electrode pairs respectively located on the wrist, palm and finger portions; and

wherein at least one of the first, second and third electrode pairs is usable as stimulation electrodes for providing a stimulus to the arm at locations corresponding to a respective at least one of the wrist, palm and finger portions and at least another of the first, second and third electrode pairs is usable as sensing electrodes for sensing an electrical potential in the arm at locations corresponding to a respective at least another of the wrist, palm and finger portions.

52. Use of the device of claim 51 for testing for carpal tunnel syndrome.

53. A method of testing nerve function in a body part, comprising:

positioning a substrate on the body part, the substrate comprising a base portion, a limb portion and an intermediate portion intermediate the base portion and the limb portion, wherein first, second and third electrode pairs are located on the base, intermediate and limb portions, respectively;

providing an electrical stimulus to a site of the body part through at least one of the first, second and third electrode pairs; and

sensing an action potential in at least another site of the body part through at least another of the first, second and third electrode pairs in response to the electrical stimulus.

54. The method of claim 53, further comprising coupling a coupling unit to the base portion to provide the electrical stimulus and to sense the action potential.

55. The method of claim 53, wherein the body part comprises a wrist and hand.

56. The method of claim 53, wherein the electrical stimulus is provided sequentially to the first and second electrode pairs and the action potential is sequentially sensed at the third electrode pair.

57. The method of claim 53, wherein the electrical stimulus is provided to the third electrode pair and the action potential is sensed at the first and second electrode pairs.

58. The method of claim 53, wherein the electrical stimulus is provided to the second electrode pair and the action potential is sensed at the first and third electrode pairs.

59. The method of claim 53, wherein the electrical stimulus is provided to the first electrode pair and the action potential is sensed at the second and third electrode pairs.

60. The method of claim 53, further comprising measuring a separation from one of the base portion and the intermediate portion to the limb portion using a distance measurement member fixed relative to one of the base portion, the intermediate portion and the limb portion.

61. The method of claim 53, wherein the limb portion is a first limb portion and the substrate further comprises a second limb portion, wherein the second limb overlies a thenar area of a hand and comprises a thenar electrode, wherein stimuli are sequentially provided to the body part through the first and second electrode pairs, and wherein the method further comprises sensing action potential using the thenar electrode and one other electrode in response to the stimuli and determining a conduction velocity of a motor nerve in the hand based on the sensed action potentials.

62. The method of claim 61, wherein the other electrode is an electrode of the third electrode pair.

64. The device of claim 61, wherein the fourth electrode is one electrode of the first or second electrode pair.

65. The device of claim 61, wherein the fourth electrode is a thenar electrode located on the substrate.

63. A device for use in measuring at least one of nerve and muscle function, comprising:

a substrate locatable on a body part, the substrate comprising a base portion, a limb portion and an intermediate portion located intermediate the base portion and the limb portion;

first and second electrode pairs respectively located on the base and limb portions;

a third electrode located on the intermediate portion, wherein the third electrode is paired with a fourth electrode located on the substrate away from the third electrode to form a third electrode pair; and

wherein at least one of the first, second and third electrode pairs is usable as stimulation electrodes for providing a stimulus to the body part and at least another of the first, second and third electrodes is usable as sensing electrodes for sensing an electrical potential in the body part in response to the stimulus.