SYSTEM AND METHOD FOR ASSESSING POSTURAL SWAY AND HUMAN MOTION

• US 20130035613A1
• Filed: 08/01/2012
• Published: 02/07/2013
• Est. Priority Date: 08/02/2011
• Status: Active Grant

• Current Assignee: Sway Medical, Inc. (Sway Medical, LLC)
• Original Assignee: Sway Medical, LLC
• Inventors: Curtiss, Chase
• Granted Patent: US 9,451,916 B2
• Time in Patent Office: Days
• US Class Current: 600/595
• 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 5/1116 Determining posture transitions
• CPC Class Codes: A61B 5/1121 Determining geometric values, e.g. centre of rotation or angular range of movement
• CPC Class Codes: A61B 5/4023 Evaluating sense of balance
• CPC Class Codes: A61B 5/6898 Portable consumer electronic devices, e.g. music players, telephones, tablet computers

Abstract

There is provided herein a system and method for performing a balance evaluation that utilizes a hand held accelerometer that measures upper body compensatory and correctional movement. Instead of testing movement in the waist or lower extremity as is commonly done, the instant invention measures thoracic trunk sway to estimate an individual'"'"'s balance via positional change algorithms. By holding the measuring device to the chest and performing one or a variety of balance tests, the instant invention can determine the amount of sway in the trunk without attached or fixed monitors, which presents a novel approach to assessing postural sway above the center of mass.

Claims

1. A method of assessing a subject'"'"'s postural stability, wherein is provided a hand-held three-component accelerometer, comprising the steps of:

(a) providing the three-component accelerometer to the subject;

(b) instructing the subject to clasp the three-component accelerometer against an upper torso of the subject;

(c) instructing the subject to perform a task while the three-component accelerometer is so clasped;

(d) continuously recording an output of said accelerometer during the subject'"'"'s performance of said task, thereby obtaining a plurality of three-component accelerometer measurements during the performance of said task;

(e) determining from at least a portion of said plurality of three-component accelerometer measurements an indicium representative of the subject'"'"'s postural stability;

(f) using at least said indicium to determine whether the subject'"'"'s postural stability is within a normal range;

(g) if the subject'"'"'s postural stability is within said normal range, taking no further action with respect to the subject; and

,

(h) if the subject'"'"'s postural stability is not within said normal range, staging an intervention with respect to the subject.

2. The method according to claim 1, wherein said task is about ten seconds in duration.

3. The method according to claim 1, wherein said three-component accelerometer is located within a mobile device selected from the group consisting of an iPhone®

, an iPod Touch®

, a Blackberry®

phone, and a Nokia®

cell phone.

4. The method according to claim 1, wherein said task is selected from a group consisting of a single leg stance test, a tandem stance test, a tandem gait test, a stationary stance test, a static postural sway test, a dynamic squat test, a single leg squat test, a step up test, an up and go test, and a jump stability test.

5. The method according to claim 1, wherein step (e) comprises the step of:

(e1) determining from at least a portion of said plurality of three-component accelerometer measurements a JERK score indicium representative of the subject'"'"'s postural stability.

6. The method according to claim 5, said JERK score is calculated according to the equation:

7. The method according to claim 1, wherein the step of staging an intervention with respect to the subject comprises at least one of sending the subject to a medical station for further testing and refusing to allow a sports participant to renter a game.

8. The method according to claim 1, wherein said normal range is determined from a plurality of ealier performances of the task by the subject.

9. A system for assessing a subject'"'"'s postural stability, comprising:

(a) a handheld computing device, comprising;

(1) a three-axis accelerometer,

(2) memory,

(3) a screen, and,

(4) a CPU in electronic communication with said screen, said three-axis accelerometer and with said memory, said CPU at least for exeucting a plurality of program instructions stored in said memory, said plurality of program instructions comprising the steps of;

(i) instructing a subject to clasp a three-component accelerometer against an upper torso of the subject;

(ii) instructing the subject to perform a task while the three-component accelerometer is so clasped;

(iii) continuously recording an output of said accelerometer during the subject'"'"'s performance of said task, thereby obtaining a plurality of three-component accelerometer measurements during the performance of said task;

(iv) determining from at least a portion of said plurality of three-component accelerometer measurements an indicium representative of the subject'"'"'s postural stability;

(v) using at least said indicium to determine whether the subject'"'"'s postural stability is within a normal range;

(vi) if the subject'"'"'s postural stability is within said normal range, displaying on said screen an indication that the subject'"'"'s postural stability is within said normal range and taking no further action with respect to the subject; and

,

(vii) if the subject'"'"'s postural stability is not within said normal range, displaying on said screen an indication that the subject'"'"'s postural stability is not within said normal range.

10. The system for assessing a subject'"'"'s postural stability according to claim 9, wherein said handheld computer is selected from the group consisting of an iPhone®

, an iPod®

, an iPod Touch®

, an Andriod®

cell phone, and a Blackberry®

cell phone.

11. The system according to claim 9, wherein said task is selected from the group consisting of a single leg stance test, a tandem stance test, a tandem gait test, a stationary stance test, a static postural sway test, a dynamic squat test, a single leg squat test, a step up test, an up and go test, and a jump stability test.

12. The system according to claim 9, wherein said normal range is determined from at least one previous performance of the task by the subject.

13. The system according to claim 9, wherein said normal range is determined from a plurality of performances of the task by a plurality of comparable subjects.

14. A method of assessing a subject'"'"'s postural stability, wherein is provided a hand-held computing device having a three-component accelerometer integral thereto, comprising the steps of:

(a) providing the hand-held computer to the subject;

(b) instructing the subject to hold the handheld computer against an upper torso of the subject;

(c) instructing the subject to perform a task while the hand held computer is so clasped;

(d) within said hand held computer continuously recording an output of said accelerometer during the subject'"'"'s performance of said task, thereby obtaining a plurality of three-component accelerometer measurements during the performance of said task;

(e) using at least a portion of said plurality of three-component accelerometer measurements to determine a numerical estimate of the subject'"'"'s postural stability; and

(f) if said numerical estimate of the subject'"'"'s postural stability is not within said normal range, staging an intervention with respect to the subject.

15. The method according to claim 14, wherein said hand held computer has a display integral thereto, further comprising the step of:

(g) if said numerical estimate of the subject'"'"'s postural stability is not within said normal range, displaying an indication that said numerical estimate of the subject'"'"'s postural stability is not within said normal range on said display of said hand held computer.

16. The method according to claim 14 wherein said hand held computer is selected from the group consisting of an iPhone®

, an iPod®

, an iPod Touch®

, an Andriod®

cell phone, and a Blackberry®

cell phone.

17. The method according to claim 14, wherein said task is selected from a group consisting of a single leg stance test, a tandem stance test, a tandem gait test, a stationary stance test, a static postural sway test, a dynamic squat test, a single leg squat test, a step up test, an up and go test, and a jump stability.

18. The method according to claim 14, wherein said handheld computer is selected from the group consisting of a iPhone®

, an iPod®

, an iPod Touch®

, an Andriod®

cell phone, and a Blackberry®

cell phone.