Relative electromyographic muscle reflex activity during motion

• US 5,263,489 A
• Filed: 06/27/1989
• Issued: 11/23/1993
• Est. Priority Date: 06/27/1989
• Status: Expired due to Fees

• Current Assignee: EMPI Incorporated (Enovis Corp.)
• Original Assignee: EMPI Incorporated (Enovis Corp.)
• Inventors: Kipnis, Alexander, Johnson, Michael T. V.
• Primary Examiner(s): Cohen, Lee S.
• Assistant Examiner(s): Lacyk, J. P.
• Application Number:
  US07/372,045
• Time in Patent Office: 1,610 Days
• Field of Search: 128/782, 128/733, 128/741, 128/724, 223/25, 364/413.27
• US Class Current: 600/546
• CPC Class Codes: A61B 5/389 Electromyography [EMG]
• CPC Class Codes: A61B 5/4082 Diagnosing or monitoring movement diseases, e.g. Parkinson, Huntington or Tourette
• CPC Class Codes: A61B 5/4528 Joints A61B5/4533, A61B5/4538 take precedence

Abstract

A method for treating electromyographic signals obtained from one or more muscles in the body which are subject to both volitional motion and externally forced motion to provide one or more indices which indicate the relative control signal energy provided to such a muscle or muscles during contractions and lengthenings thereof.

Claims

1. A method for treating selected myographic signals obtained from a first muscle for operating a skeletal joint in a body subject to both volitional motion and externally forced motion to provide a first index based thereon indicative of control directives provided to said first muscle during contractions and lengthenings thereof, said method comprising:

directing volitionally said first muscle to cause an actuator portion of said joint to follow a moving target with respect to a base portion of said joint while a bodily portion extending from said actuator portion of said joint is connected to a mechanical means, said mechanical means for selectively providing applications of external controlled forces to said bodily portion;

acquiring a first plurality of representations of electromyographic signal portions from said first muscle with each such electromyographic signal portion therein occurring during a corresponding volitional contraction of said first muscle as part of a plurality of volitional contractions thereof with selected ones of said plurality of volitional contractions being accompanied by a corresponding application of a selected external controlled force applied for a selected duration to said first muscle by said mechanical means;

acquiring a second plurality of representations of electromyographic signal portions from said first muscle with each such electromyographic signal portion therein occurring during a corresponding lengthening of said first muscle as part of a plurality of lengthenings thereof with selected ones of said plurality of lengthenings being accompanied by a corresponding application of a selected external controlled force applied for a selected duration to said first muscle by said mechanical means; and

forming said first index based on values of those of said first plurality of representations of electromyographic signal portions which have occurred in conjunction with an occurrence of a said application of an external controlled force relative to values of those of said second plurality of representations of electromyographic signal portions which have occurred in conjunction with an occurrence of said application of an external controlled force.

2. The method of claim 1 further comprising forming a second index based on values of those of said first plurality of representations of electromyographic signal portions which have occurred absent any coincidental occurrence of a said application of an external controlled force relative to values of those of said second plurality of representations of electromyographic signal portions which have occurred absent any coincidental occurrence of a said application of an external controlled force.

3. The method of claim 2 wherein said second index is based on a ration of values of those of said first plurality of representations of electromyographic signal portions which have occurred absent any coincidental occurrence of a said application of an external controlled force to values of those of said second plurality of representations of electromyographic signal portions which have occurred absent any coincidental of a said application of an external controlled force.

4. The method of claim 3 wherein said second index is based on said ratio by being dependent on a logarithm of said ratio.

5. The method of claim 4 wherein each said electromyographic signal portion in said first plurality of representations of electromyographic signal portions which has occurred in conjunction with an occurrence of a said application of an external controlled force has subtracted therefrom a value based on an average of values of those of said first plurality of representations of electromyographic signal portions which have occurred absent any coincidental occurrence of a said application of an external controlled force.

6. The method of claim 1 further comprising forming a second index based on values of those of said first plurality of representations of electromyographic signal portions which have occurred in conjunction with an occurrence of a said application of an external controlled force relative to values of those of both of said first and second pluralities of representations of electromyographic signal portions which have occurred in conjunction with an occurrence of a said application of an external controlled force.

7. The method of claim 6 wherein each said electromyographic signal portion in said first plurality of representations of electromyographic signal portions which has occurred in conjunction with an occurrence of a said application of an external controlled force has subtracted therefrom a value based on an average of values of those of said first plurality of representations of electromyographic signal portions which have occurred absent any coincidental occurrence of a said application of an external controlled force.

8. The method of claim 6 wherein said second index is based on a ratio of values of said first plurality of representations of electromyographic signal portions which have occurred in conjunction with an occurrence of a said application of an external controlled force to values of those of both of said first and second pluralities of representations of electromyographic signal portions which have occurred in conjunction with an occurrence of a said application of an external controlled force.

9. The method of claim 8 wherein said second index is based on said ratio by being dependent on a logarithm of said ratio.

10. The method of claim 9 wherein each said electromyographic signal portion in said first plurality of representations of electromyographic signal portions which has occurred in conjunction with an occurrence of a said application of an external controlled force has subtracted therefrom a value based on an average of values of those of said first plurality of representations of electromyographic signal portions which have occurred absent any coincidental occurrence of a said application of an external controlled force.

11. The method of claim 1 further comprising forming a second index based on values of those of said second plurality of representations of electromyographic signal portions which have occurred in conjunction with an occurrence of a said application of an external controlled force relative to values of those of both of said first and second pluralities of representations of electromyographic signal portions which have occurred in conjunction with an occurrence of a said application of an external controlled force.

12. The method of claim 11 wherein each said electromyographic signal portion in said first plurality of representations of electromyographic signal portions which has occurred in conjunction with an occurrence of a said application of an external controlled force has subtracted therefrom a value based on an average of values of those of said first plurality of representations of electromyographic signal portions which have occurred absent any coincidental occurrence of a said application of an external controlled force.

13. The method of claim 11 wherein said second index is based on a ratio of values of those of said second plurality of representations of electromyographic signal portions which have occurred in conjunction with an occurrence of a said application of an external controlled force to values of those of both of said first and second pluralities of representations of electromyographic signal portions which have occurred in conjunction with the occurrence of a said application of an external controlled force.

14. The method of claim 13 wherein said second index is based on said ratio by being dependent on a logarithm of said ratio.

15. The method of claim 14 wherein each said electromyographic signal portion in said first plurality of representations of electromyographic signal portions which has occurred in conjunction with an occurrence of a said application of an external controlled force has subtracted therefrom a value based on an average of values of those of said first plurality of representations of electromyographic signal portions which have occurred absent any coincidental occurrence of a said application of an external controlled force.

16. The method of claim 1 wherein each said electromyographic signal portion in said first plurality of representations of electromyographic signal portions which has occurred in conjunction with an occurrence of a said application of an external controlled force has subtracted therefrom a value based on an average of values of those of said first plurality of representations of electromyographic signal portions which have occurred absent any coincidental occurrence of a said application of an external controlled force.

17. The method of claim 1 wherein each said electromyographic signal portion in said first plurality of representations of electromyographic signal portions which has occurred in conjunction with an occurrence of a said application of an external controlled force is divided by a value based on an average of values of those of said first plurality of representations of electromyographic signal portions which have occurred absent any coincidental occurrence of a said application of an external controlled force.

18. The method of claim 1 further comprising:

acquiring a third plurality of representations of electromyographic signal portions from a second muscle in said body with each such electromyographic signal portion occurring during a corresponding volitional contraction of said second muscle as part of a plurality of volitional contractions with selected ones of said plurality of volitional contractions being accompanied by a corresponding application of a selected external controlled force applied for a selected duration to said second muscle by said mechanical means; and

acquiring a fourth plurality of representations of electromyographic signal portions from said second muscle with each such electromyographic signal portion occurring during a corresponding lengthening of said second muscle as part of a plurality of lengthenings thereof with selected ones of said plurality of lengthenings being accompanied by a corresponding application of a selected external controlled force applied for a selected duration to said second muscle by said mechanical means.

19. The method of claim 18 further comprising forming a second index based on values of those of said third plurality of representations of electromyographic signal portions which have occurred in conjunction with an occurrence of a said application of an external controlled force relative to values of those of said fourth plurality of representations of electromyographic signal portions which ave occurred in conjunction with an occurrence of a said application of an external controlled force.

20. The method of claim 19 wherein each of said plurality of volitional contractions of said first muscle has a corresponding one of said plurality of lengthenings of said second muscle, and each of said plurality of lengthenings of said first muscle has a corresponding one of said plurality of volitional contractions of said second muscle.

21. The method of claim 20 wherein said first muscle and said second muscle are alternatingly agonist and antagonist muscles for operating a skeletal joint and are volitionally directed to cause an actuator portion of said joint to follow a reciprocating position target with respect to said base of said joint while said actuator side of said joint is in a bodily portion connected to said mechanical means.

22. The method of claim 20 wherein there is a correspondence between each said representation in said first plurality of representations of electromyographic signal portions and a said representation in said third plurality of representations of electromyographic signal portions due to similarities in conditions in acquiring each of said corresponding representations, and wherein said method further comprises forming a joint plurality of representations with each such representation in said joint plurality being based on relative values of a corresponding pair of correspondence representations from said first and third pluralities of representations of electromyographic signal portions, and forming a joint index based on values of said joint plurality of representation.

23. The method of claim 20 wherein there is a correspondence between each said representation in said second plurality of representations of electromyographic signal portions and a said representation in said fourth plurality of representations of electromyographic signal portions due to similarities in conditions in acquiring each of said corresponding representations, and wherein said method further comprises forming a joint plurality of representations with each such representation in said joint plurality being based on relative values of a corresponding pair of correspondence representations from said second and fourth pluralities of representations of electromyographic signal portions, and forming a joint index based on values of said joint plurality of representation.

24. The method of claim 1 wherein said first index is based on a ratio of values of those of said first plurality of representations of electromyographic signal portions which have occurred in conjunction with an occurrence of a said application of an external controlled force to values of those of said second plurality of representations of electromyographic signal portions which have occurred in conjunction with an occurrence of a said application of an external controlled force.

25. The method of claim 24 wherein said first index is based on said ratio by being dependent on a logarithm of said ratio.

26. The method of claim 25 wherein each aid electromyographic signal portion in said first plurality of representations of electromyographic signal portions which as occurred in conjunction with an occurrence of a said application of an external controlled force has subtracted therefrom a value based on an average of values of those of said first plurality of representations of electromyographic signal portions which have occurred absent any coincidental occurrence of a said application of an external controlled force.