Detection and characterization of head impacts

• US 9,149,227 B2
• Filed: 07/15/2011
• Issued: 10/06/2015
• Est. Priority Date: 07/15/2010
• Status: Active Grant

• Current Assignee: Cleveland Clinic Foundation
• Original Assignee: Cleveland Clinic Foundation
• Inventors: Benzel, Edward C., Miele, Vincent J., Bartsch, Adam J., Gilbertson, Lars G.
• Primary Examiner(s): Satanovsky, Alexander
• Application Number:
  US13/184,385
• Publication Number:
  US 20120143526A1
• Time in Patent Office: 1,544 Days
• Field of Search: 702/41, 702/42, 702/141, 345/440, 345/473, 345/619
• US Class Current: 1/1
• CPC Class Codes: A42B 3/046 Means for detecting hazards or accidents
• CPC Class Codes: A61B 2503/10 Athletes
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• CPC Class Codes: A61B 2562/0247 Pressure sensors
• CPC Class Codes: A61B 2562/0261 Strain gauges
• CPC Class Codes: A61B 2562/028 Microscale sensors, e.g. electromechanical sensors [MEMS]
• CPC Class Codes: A61B 5/1114 Tracking parts of the body
• CPC Class Codes: A61B 5/1121 Determining geometric values, e.g. centre of rotation or angular range of movement
• CPC Class Codes: A61B 5/1122 of movement trajectories
• CPC Class Codes: A61B 5/4064 Evaluating the brain A61B5/031, A61B5/369, A61B5/14553 take precedence
• CPC Class Codes: A61B 5/6803 Head-worn items, e.g. helmets, masks, headphones or goggles
• CPC Class Codes: A61B 5/682 Mouth, e.g., oral cavity; tongue; Lips; Teeth
• CPC Class Codes: A61B 5/7253 characterised by using transforms
• CPC Class Codes: A61B 5/7264 Classification of physiological signals or data, e.g. using neural networks, statistical classifiers, expert systems or fuzzy systems neural networks per se G06N3/00; expert systems per se G06N5/00
• CPC Class Codes: A61B 5/7267 involving training the classification device
• CPC Class Codes: A61B 5/7278 Artificial waveform generation or derivation, e.g. synthesising signals from measured signals A61B5/327 takes precedence
• CPC Class Codes: A61B 5/7282 Event detection, e.g. detecting unique waveforms indicative of a medical condition A61B5/4094, A61B5/4818, A61B5/349, A61B5/0823 take precedence
• CPC Class Codes: A61B 5/746 Alarms related to a physiological condition, e.g. details of setting alarm thresholds or avoiding false alarms alarms per se G08B
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems

Abstract

Systems and methods are provided for determining an acceleration at a location of interest within one of a user'"'"'s head and neck. At least one of linear acceleration data, angular acceleration data, angular velocity data, and orientation data is produced using at least one sensing device substantially rigidly attached to an ambient-accessible surface of the user'"'"'s head. The location of interest is represented relative to a position of the at least one sensing device as a time-varying function. An acceleration at the location of interest is calculated as a function of the data produced at the sensing device and the time-varying function representing the location of interest. The calculated acceleration at the location of interest is provided to at least one of the user and an observer in a human-perceptible form.

Claims

1. A non-transitory computer readable medium storing executable instructions executable by an associated processor to perform a method for determining an acceleration at a location of interest within one of a user'"'"'s head and neck, comprising:

receiving at least one of linear acceleration data, angular acceleration data, angular velocity data, and orientation data using a sensor assembly substantially rigidly attached to an ambient-accessible surface of the user'"'"'s head at an associated position;

selecting one of a plurality of available time-varying functions representing the location of interest according to the received at least one of linear acceleration data, angular acceleration data, angular velocity data, and orientation data;

calculating an acceleration at the location of interest as a function of the data produced at the sensor assembly and the time-varying function representing the location of interest as a linear combination of at least the linear acceleration and a cross-product of the angular velocity and the time-varying velocity of the center of gravity; and

providing the calculated acceleration at the location of interest to at least one of the user and an observer in a human-perceptible form.

2. The non-transitory computer readable medium of claim 1, wherein the sensor assembly is contained entirely within one of a mouth guard and a lip guard worn by the user, and calculating the acceleration at the location of interest comprises calculating the acceleration at the location of interest solely as a function of the data produced at the sensor assembly and the time-varying function representing the location of interest.

3. The non-transitory computer readable medium of claim 1, wherein the location of interest is a center of gravity of the head of the user.

4. The non-transitory computer readable medium of claim 1, wherein the location of interest is a location within one of a frontal lobe, parietal lobe, temporal lobe, occipital lobe, cerebellum, medulla oblongata, pons, thalamus, gyrus, fornix, amygdyla, hippocampus, cranium, facial bones, maxilla, mandible, cerebrospinal fluid, occipito-cervical junction, cervical spine, vertebral bodies, spinal cord, spinal nerves, spinal vessels, basal ganglia, peri-vascular spaces, septum, white-gray matter junctions, bridging veins, corpus callosum, fissure, cavity sinus, meninges, falx, dura, arachnoid, and pia matter of the user.

5. The non-transitory computer readable medium of claim 1, further comprising determining one of a Gadd Severity Index, a von Mises stress, and a Head Injury Criterion from the calculated acceleration.

6. The non-transitory computer readable medium of claim 1, further comprising calculating one of an impact force, a strain rate, and a loading rate at the location of interest from the calculated acceleration.

7. The non-transitory computer readable medium of claim 1, wherein the calculated acceleration is an angular acceleration, and further comprising calculating one of an angular jerk at the location of interest and an angular momentum of the user'"'"'s head from the calculated acceleration.

8. The non-transitory computer readable medium of claim 1, further comprising calculating one of a Generalized Acceleration Model for Brain Injury Threshold, a relative motion damage measure, a dilatational damage measure, and a neck injury criterion from the calculated acceleration.

9. The non-transitory computer readable medium of claim 1, further comprising calculating one of a Head Impact Power parameter, a weighted principle component score, a strain energy, and a cumulative strain damage measure from the calculated acceleration.

10. The non-transitory computer readable medium of claim 1, further comprising calculating one of a peak pressure, a principal strain, a sheer stress, and a product of a strain and a strain rate from the calculated acceleration.

11. A system for characterizing an impact to a user comprising:

a sensor assembly configured to measure at least a linear acceleration and angular velocity of the sensor assembly;

a data transform component operatively connected to the sensor assembly and configured to represent a location of interest in one of the head and the neck of the user relative to a position of the sensor assembly as a time-varying function, including at least a time-varying velocity of the location of interest, and to calculate an acceleration at the location of interest as a linear combination of at least the linear acceleration and a cross-product of the angular velocity and the time-varying velocity of the location of interest; and

a system interface configured to provide the calculated acceleration at the location of interest to a user in a human-perceptible form.

12. The system of claim 11, the sensor assembly comprising a plurality of linear accelerometers implemented as microelectromechanical (MEMS) systems.

13. The system of claim 11, the sensor assembly comprising a plurality of angular accelerometers implemented as MEMS systems.

14. The system of claim 11, the sensor assembly comprising a plurality of angular velocity sensors implemented as MEMS systems.

15. The system of claim 11, the sensor assembly comprising a plurality of angular position sensors implemented as MEMS systems.

16. The system of claim 11, the sensor assembly comprising a plurality and combination of linear accelerometers, angular accelerometers, angular velocity sensors and angular position sensors implemented as MEMS systems.

17. The system of claim 11, wherein the sensor assembly is implemented entirely in one of a mouth guard and a lip guard worn by the user, and the data transform component is configured to calculate the acceleration at the location of interest solely as a function of the data measured at the sensor assembly and the time-varying function representing the location of interest.

18. The system of claim 17, the one of the mouth guard and the lip guard being formed from multiple layers of material with the sensor assembly being mounted in one layer in an elongate pattern.

19. The system of claim 17, the one of the mouth guard and the lip guard comprising a wireless transmitter to provide the measured linear acceleration and angular velocity to the data transform component.

20. The system of claim 17, the one of the mouth guard and the lip guard comprising an on-board wired transmitter with data storage to provide the measured linear acceleration and angular velocity to the data transform component.

21. The system of claim 17, wherein the data transform component is mounted on a headpiece worn by the user, and the one of the mouth guard and the lip guard is connected to the data transform component via a wired connection.

22. The system of claim 11, the data transform component being configured to represent the location of interest relative to the sensor assembly as a time-varying function according to a model of the movement of a brain when exposed to various kinematics and kinetics.

23. The system of claim 11, the system interface comprising a remote warning device that alerts the user when the calculated acceleration exceeds a threshold value.

24. The system of claim 11, the system interface comprising an on-board warning device that alerts the user when the calculated acceleration exceeds a threshold value.

25. The system of claim 11, the data transform component being configured to select the time-varying function from one of a plurality of available time-varying functions representing the location of interest according to the measured linear acceleration and angular velocity.

26. A system for characterizing an impact to a head of an athlete during an athletic event comprising:

a sensor assembly encapsulated entirely within one of a mouth guard and a lip guard worn by the athlete and configured to measure at least the linear acceleration and the angular velocity of the sensor assembly;

a data transform component operatively connected to the sensor assembly and configured to calculate the acceleration at a center of gravity of the head solely from the measured at least one of the linear acceleration, angular velocity, angular acceleration, and orientation of the sensor assembly and a position of the sensor assembly relative to the center of gravity of the head, the data transform component being configured to represent a location of the center of gravity of the head relative to a position of the sensor assembly as a time-varying function comprising at least a time-varying velocity of the location of interest and calculate the acceleration at the center of gravity as a linear combination of at least the linear acceleration and a cross-product of the angular velocity and the time-varying velocity of the center of gravity; and

a system interface configured to provide the calculated acceleration at the center of gravity to one of the athlete, a coach of the athlete, a family member of the athlete, a trainer of the athlete, an official associated with the athletic event, and an audience associated with the athletic event.

27. The system of claim 26, wherein the sensor assembly is configured to measure each of the linear acceleration, angular velocity, angular acceleration, and orientation of the sensor assembly.

28. The system of claim 26, the data transform component being configured to select the time-varying function from one of a plurality of available time-varying functions representing the center of gravity according to the measured at least one of linear acceleration, angular acceleration, angular velocity, and orientation.