SYSTEM, APPARATUS AND METHOD FOR MEASUREMENT OF MUSCLE STIFFNESS

• US 20170020437A1
• Filed: 03/11/2015
• Published: 01/26/2017
• Est. Priority Date: 03/12/2014
• Status: Active Grant

• Current Assignee: Københavns Universitet, Movotec A/S
• Original Assignee: Kbenhavns Universitet, Movotec A/S
• Inventors: Nielsen, Bo Jens, Westergaard, Johnny Erik, Bilde, Peder Esben
• Granted Patent: US 10,575,772 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• CPC Class Codes: A61B 5/1107 Measuring contraction of parts of the body, e.g. organ, muscle apparatus for measuring work or force in general G01L
• CPC Class Codes: A61B 5/1122 of movement trajectories
• CPC Class Codes: A61B 5/389 Electromyography [EMG]
• CPC Class Codes: A61B 5/4519 Muscles A61B5/389, A61B5/224 take precedence
• CPC Class Codes: A61B 5/6831 Straps, bands or harnesses
• CPC Class Codes: A61B 5/7278 Artificial waveform generation or derivation, e.g. synthesising signals from measured signals A61B5/327 takes precedence

Abstract

A system, an apparatus, and a method for measuring muscle stiffness in a predetermined joint of an individual are provided. The system and apparatus comprises a measuring unit and a processing unit. The measuring unit is configured to be applied to a body segment of the predetermined joint. The processing unit is configured to: receive a plurality of data sets from the at least one measurement device, analyze the plurality of data sets for one or more indications of an elicited stretch reflex, and calculate a muscle stiffness score. The muscle stiffness score is based on at least a difference between a first stiffness and a second stiffness. The first stiffness is determined from the first subset, and the second stiffness is determined from the second subset.

Claims

1. A system for measuring muscle stiffness in a predetermined joint of an individual, the system comprising a measuring unit and a processing unit, the measuring unit being configured to be applied to a body segment of the predetermined joint and comprising a housing and at least one measurement device comprising a force transducer, and wherein the processing unit is configured to:

receive a plurality of data sets from the at least one measurement device, the plurality of data sets comprising measurement data measured during a plurality of trials, the plurality of trials comprising moving the body segment with a plurality of angular velocities by an examiner applying external force to the body segment via the measuring unit, the measurement data comprising applied force data;

analyze the plurality of data sets for one or more indications of an elicited stretch reflex based on the measurement data, to determine a first subset and a second subset of the plurality of data sets, the first subset comprising data sets in which at least one of the one or more indications of an elicited stretch reflex is present, and the second subset comprising data sets in which none of the one or more indications of an elicited stretch reflex is present; and

calculate a muscle stiffness score based on at least a difference between a first stiffness and a second stiffness, wherein the first stiffness is based on applied force data and is determined from the first subset, and wherein the second stiffness is based on applied force data and is determined from the second subset.

17. The system according to claim 1, wherein the at least one measurement device comprises a gyroscope, and the measurement data comprises angular velocity data.

18. The system according to claim 1, wherein the at least one measurement device comprises an accelerometer, and the measurement data comprises acceleration data.

19. The system according to claim 18, wherein the at least one measurement device comprises a gyroscope, and the measurement data comprises angular velocity data, and wherein the processing unit calculates acceleration and angular velocity of the measuring unit based on angular velocity data received from the gyroscope and acceleration data received from the accelerometer.

20. The system according to claim 1, wherein the measuring unit comprises a handle, and wherein the force transducer is configured for measuring force applied to the handle.

21. The system according to claim 1, wherein analyzing the plurality of data sets comprises analyzing applied force data of the plurality of data sets.

22. The system according to claim 1, wherein the at least one measurement device comprises a muscular activity detection unit, and the measurement data comprises muscular activity data.

23. The system according to claim 22 wherein analyzing the plurality of data sets comprises analyzing muscular activity data of the plurality of data sets.

24. The system according to claim 1, wherein the plurality of data sets comprises a trial data set and, the processing unit is configured to analyze the trial data set for the one or more indications of an elicited stretch reflex, and the processing unit is configured to output a first signal if the trial data set comprises at least one of the one or more indications of an elicited stretch reflex.

25. The system according to claim 1, wherein the processing unit is further configured to determine a distance from a joint center of the predetermined joint to a position of the measuring unit, and wherein the first stiffness and the second stiffness are based on the distance.

26. The system according to claim 1, wherein the housing comprises the at least one measurement device, and wherein the housing is a rigid housing.

27. The system according to claim 1, wherein the measuring unit comprises a wireless transceiver for wirelessly communicating with an additional device, wherein the additional device comprises the processing unit.

28. The system according to claim 1, wherein the housing comprises the processing unit.

2-16. -16. (canceled)

29. A method for calculating a muscle stiffness score, the method comprising:

receiving a plurality of data sets comprising measurement data measured during a plurality of trials, the plurality of trials comprising moving a body segment with a plurality of angular velocities by an examiner applying external force to the body segment via a measuring unit, the measurement data comprising applied force data;

analyzing the plurality of data sets for one or more indications of an elicited stretch reflex based on the measurement data, to determine a first subset and a second subset of the plurality of data sets, the first subset comprising data sets in which at least one of the one or more indications of an elicited stretch reflex is present, and the second subset comprising data sets in which none of the one or more indications of an elicited stretch reflex is present; and

calculating the muscle stiffness score based on at least a difference between a first stiffness and a second stiffness, wherein the first stiffness is based on applied force data and is determined from the first subset, and wherein the second stiffness is based on applied force data and is determined from the second subset.

30. The method according to claim 29, wherein analyzing the plurality of data sets comprises at least analyzing force data and/or muscular activity data of the plurality of data sets.

31. A muscle stiffness apparatus for measuring muscle stiffness in a predetermined joint of an individual, comprising:

a housing,

at least one measurement device comprising a force transducer, and

a processing unit, wherein the processing unit is configured to;

receive a plurality of data sets from the at least one measurement device, the plurality of data sets comprising measurement data measured during a plurality of trials, the plurality of trials comprising moving the body segment with a plurality of angular velocities by an examiner applying external force to the body segment via the muscle stiffness apparatus, the measurement data comprising applied force data,

analyze the plurality of data sets for one or more indications of an elicited stretch reflex based on the measurement data, to determine a first subset and a second subset of the plurality of data sets, the first subset comprising data sets in which at least one of the one or more indications of an elicited stretch reflex is present, and the second subset comprising data sets in which none of the one or more indications of an elicited stretch reflex is present, and

calculate a muscle stiffness score based on at least a difference between a first stiffness and a second stiffness, wherein the first stiffness is based on applied force data and is determined from the first subset, wherein the second stiffness is based on applied force data and is determined from the second subset, and

wherein the muscle stiffness apparatus is configured to be applied to a body segment of the predetermined joint.