LOWER LIMB LOADING ASSESSMENT SYSTEMS AND METHODS

• US 20190328284A1
• Filed: 07/11/2019
• Published: 10/31/2019
• Est. Priority Date: 03/25/2014
• Status: Active Grant

• Current Assignee: IMeasureU Limited (Oxford Metrics PLC)
• Original Assignee: IMeasureU Limited (Oxford Metrics PLC)
• Inventors: Finch, Mark, Besier, Thor Franciscus
• Granted Patent: US 11,744,485 B2
• Time in Patent Office: Days
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• CPC Class Codes: A61B 5/1036 Measuring load distribution, e.g. podologic studies
• CPC Class Codes: A61B 5/112 Gait analysis
• CPC Class Codes: A61B 5/1124 Determining motor skills
• CPC Class Codes: A61B 5/6829 Foot or ankle
• CPC Class Codes: G01P 15/00 Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
• CPC Class Codes: G01P 15/18 in two or more dimensions

Abstract

A lower limb loading assessment system having at least one motion sensor mounted to a subject'"'"'s lower limb that is configured to sense the tibial shockwaves experienced by the lower limb as the subject performs a repetitive physical activity involving repetitive footstrikes of the lower limb with a surface. The motion sensor comprises an accelerometer that is configured to sense acceleration data in at least three axes and generate representative acceleration data over a time period associated with the physical activity. The acceleration data represents a series of discrete tibial shockwaves from the discrete footstrikes. A data processor receives the tibial shockwave data and processes that to generate output feedback data comprising data to assist the subject to minimize future loading in their lower limbs.

Claims

1. A cumulative load monitoring system for lower limbs of a subject, the system comprising:

one or more motion sensors secured or mounted to one of or both of the subject'"'"'s lower limbs, the sensor(s) being configured to sense the tibial shockwaves experienced by the lower limb(s) as the subject engages in physical activity involving repetitive footstrikes of the lower limb(s) with a surface and generate representative tibial shockwave data; and

a data processor that is configured to receive the tibial shockwave data sensed by the one or more sensors, and wherein the processor is configured to process the received tibial shockwave data and generate feedback data in the form of an estimate of the subject'"'"'s cumulative load stimulus over a time period or one or more activity sessions.

2. The cumulative load monitoring system according to claim 1 wherein the data processor is configured to compare the cumulative load stimulus to a threshold stored for the subject and generate an alert or notification if the threshold is exceeded.

3. The cumulative load monitoring system according to claim 1 wherein the data processor is configured to generate the feedback data of an estimate of cumulative load stimulus based at least partly on identifying and extracting peak shock data from the received tibial shockwave data.

4. The cumulative load monitoring system according to claim 1 wherein the or each motion sensor comprises an accelerometer that is configured to sense acceleration data in at least three axes and generate representative acceleration data as the subject engages in physical activity, and the representative tibial shockwave data generated by the or each motion sensor comprises the acceleration data which represents a series of discrete tibial shockwaves from the discrete footstrikes.

5. The cumulative load monitoring system according to claim 4 wherein the data processor is configured to generate the feedback data of an estimate of cumulative load stimulus based at least partly on identifying and extracting peak shock data from the received tibial shockwave data.

6. The cumulative load monitoring system according to claim 5 wherein the data processor is configured to identify and extract the peak shock data from the received tibial shockwave data by converting the 3-axes acceleration data of the tibial shockwave data into resultant acceleration magnitude data and extracting peak shock data representing the peak resultant acceleration magnitude data associated with each discrete footstrike.

7. The cumulative load monitoring system according to claim 1 wherein the data processor is configured to receive tibial shockwave data from a single activity session engaged in by the subject and generates the feedback data of an estimate of the subject'"'"'s cumulative load stimulus in the form of a session load stimulus.

8. The cumulative load monitoring system according to claim 1 wherein the data processor is configured to receive tibial shockwave data from multiple activity sessions engaged in by the subject and generate feedback data of an estimate of the subject'"'"'s cumulative load stimulus relating to those multiple activity sessions.

9. The cumulative load monitoring system according to claim 1 wherein the data processor is configured to receive tibial shockwave data from a plurality of activity sessions engaged in by the subject from a single day and generate the feedback data of an estimate of the subject'"'"'s cumulative load stimulus in the form of a daily load stimulus (DLS).

10. The cumulative load monitoring system according to claim 9 wherein the data processor is configured to compare the generated DLS to a threshold DLS stored for the subject and generate an alert or notification if the threshold is exceeded.

11. The cumulative load monitoring system according to claim 9 wherein the data processor is configured to generate the DLS by:

processing the received tibial shockwave data to segment the data into predefined types of activities;

extracting peak shock data from each segment of data; and

determining the DLS based on the peak shock data and its associated type of activity.

12. The cumulative load monitoring system according to claim 11 wherein the predefined types of activities comprise:

running, walking, and resting.

13. The cumulative load monitoring system according to claim 9 wherein the data processor is further configured to apply a bone stimulus saturation model for saturation and recovery when generating the DLS.

14. The cumulative load monitoring system according to claim 1 wherein the data processor is configured to continuously update the feedback data representing an estimate of cumulative load stimulus based on new received tibial shockwave data relating to the time period or one or more activity sessions.

15. The cumulative load monitoring system according to claim 1 wherein the data processor is communicatively coupled to the one or more motion sensors over a data link.

16. The cumulative load monitoring system according to claim 1 wherein the data processor is onboard the or each motion sensor.

17. The cumulative load monitoring system according to claim 1 wherein the one or more motion sensors are secured or mounted to the subject'"'"'s lower limb in any of the following locations:

between the femoral epicondyle and medial malleolus, in the region of the lower ⅓

^rd of the tibia, in the region of the medial part of the tibia, in the region adjacent and above the medial malleolus of the tibia, or in the region adjacent and above the lateral malleolus of the tibia.

18. A method of assessing lower limb shock of a subject, comprising:

receiving tibial shockwave data from one or more motion sensors secured or mounted to one of or both of the subject'"'"'s lower limbs, the sensor(s) being configured to sense the tibial shockwaves experienced by the lower limb(s) as the subject engages in physical activity involving repetitive footstrikes of the lower limb(s) with a surface and generates representative tibial shockwave data;

processing the received tibial shockwave data; and

generating feedback data in the form of an estimate of the subject'"'"'s cumulative load stimulus over a time period or one or more activity sessions.

19. The method according to claim 18 further comprising comparing the cumulative load stimulus to a threshold stored for the subject and generating an alert or notification if the threshold is exceeded.

20. The method according to claim 18 wherein generating feedback data in the form of an estimate of the subject'"'"'s cumulative load stimulus is based at least partly on identifying and extracting peak shock data from the received tibial shockwave data.