Team IPO: System for quantifying K-Level assessment in amputees

Connor Bortz, Matthew Galbraith, Jessica Lewis, Chelsea Madden, Anthony Rossi

Background Summary

$5,000 $50,000

Background Summary

• K-Level system for rating amputee assessment:

• K-0: Does Not Qualify.

• K-1: Fixed-pace on level ground.

• K-2: Walk over minor barriers.

• K-3: Varied-cadence and over most barriers.

• K-4: Athletic Ability with Prosthetic.

Background Summary

• Too qualitative.

• Distinction between K-2 to K-3

• Initiative to ‘work their way up’

Scope

To develop a system to measure various gait parameters that pertain to ambulating to be used for diagnosis justification, and prosthetic prescription.

Product Desired Specifications

• Constraints

– Product must abide by any FDA, FCC, or other existing codes and regulations.

– Project must make substantial progress towards use on amputee subjects before final deadline, December 11th.

– Project must be compatible with existing prostheses.

Product Desired Specifications

• Wants:

1.) Measuring Capabilities

2.) Data Acquisition/Storage

3.) Low-Cost

4.) Portability

5.) Comfort

6.) Water-proof

7.) User-Readability

8.) Aesthetic

Product Desired Specifications

• Within “Measuring Capabilities”, there are prioritized parameters:

1.) Number of Steps

2.) Walking Cadence

3.) Distance

4.) Elevation detection.

K-1:

K-2:

K-3:

Metrics

Metric Description Target ValueReference

(See Appendix A)

Number of Steps The device will measure the number of steps the user takes over a certain period of time.

±10% of actual steps [4]

Change in cadence The software will detect changes in cadence. ±10% change in cadence

Distance The design will measure the distance the user covers in meters.

±10% of actual distance [2]

Incline/Decline The device will recognize whether the user travels over an incline or decline. 20° American

Disability Act

Data AcquisitionThe device will be able to store data over a certain

amount of time. This data will be able to be uploaded in a certain amount of time.

25000 hours Current Technology

Affordability The device should be sold to consumer below target value. <$100 Sponsor

Feedback

Benchmarking

Hardware Software Data Analysis

Actibelt®

• Worn around the hip• Available for rent• Readout software

included• ~$260 per belt per month

Fitbit® One TM

• Worn around the body• Available for purchase• Data readout on device• ~$99.99 per device

Hardware Options

In-House Manufacturing• Labor intensive• Unknown timetable• Custom software

required• Cost undetermined

Hardware Selection

- For Hardware: FitBit® OneTM best fits the metrics for the desired specifications

Fitabase• Intraday data available in

minute intervals• Customizable user interface

Fitbit® OneTM Online• Online software provided by

Fitbit® Intraday data available in fifteen minute intervals

• No customization allowed

Software Options

Custom Software• Requires registering with

Fitbit®

• Google Doc has embedded Fitbit®

extraction• Data intervals in day-by-

day basis

Software Selection

- For Software: Fitabase best fits the metrics for the desired specifications

Final Design

Fitbit® OneTM

Fitabase Software Development

Test PlanHardware Testing: Verify standard Fitbit® outputs for normal and amputee subjects

Software Testing: Validate desired system outcomes, e.g. minute-by-minute step count, stair climb, change in cadence, in normal subjects

Clinical Trials: Field testing of integrated hardware and software system on cohort of amputees with a range of K-levels

Hardware Testing: Healthy Subjects

• 2 healthy subjects (M 22 yo, F 21 yo)

• Walking tests on treadmill & stairs– Fast/slow cadence– Flat & incline– Location of FitBit®

• Outcomes from Fitbit® software (15-minute intervals)

– Step count

– Distance– Floors

Hardware Testing: Healthy Subjects

• Fitbit® Measurement Error (across all trials)– Steps: 11±13% – Floors: 0%

• Observations– Incline only measured with change in

elevation– Cadence not a direct outputExample of standard output from Fitbit®

Hardware Testing: Amputee Subjects

• 1 amputee subject (M, 39 yo)

• Walking tests outside – Walking test (30 steps)– Stair test (1 flight of stairs)

Results: AccuracyStep Count = 93.75%

Stair Climb = 100%

Test PlanHardware Testing: Verify standard Fitbit® outputs for normal and amputee subjects

Software Testing: Validate desired system outcomes, e.g. minute-by-minute step count, stair climb, change in cadence, in normal subjects

Clinical Trials: Field testing of integrated hardware and software system on cohort of amputees with a range of K-levels

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Software Test #1

• 3 healthy subjects (M, 21-22 yo)

• Walking tests on indoor track & stairs– Fast/slow cadence– With/without obstacles– Pedometer & observation as gold

standard

• Outcomes from Fitabase® (min-by-min)– Step count– Distance– Elevation

* Data shown for Subject 2, 9 min walk on flat ground with change in cadence every 3 min

Software Test #2

• 3 healthy subjects (M 21 yo, 2xF 21 yo)

• Walking tests– Simulated daily activity outside/inside

with obstacles– Random changes in cadence

• Cadence change as primary outcome– Blinded data analysis– Varied threshold for detecting change

in cadence– Error in predicted versus actual change

in cadence

* Data shown for Subject 3, 23 min. walk test in native environment with subject-selected change in cadence

★★

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Test PlanHardware Testing: Verify standard Fitbit® outputs for normal and amputee subjects

Software Testing: Validate desired system outcomes, e.g. minute-by-minute step count, stair climb, change in cadence, in normal subjects

Clinical Trials: Field testing of integrated hardware and software system on cohort of amputees with a range of K-levels

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✔

Clinical Trials: Methods

• Subjects– 60 Amputees: K-1 (15), K-2 (15), K-3 (15), K-

4(15)– 20 Healthy controls

• Walking tests– Clinical assessment: 6-minute walk

test, 10m test– Normal daily activity for a week

• Outcome Measures– Patient records– Clinical assessment– Custom outcomes from Fitabase– User survey

University of Delaware Internal Review Board (IRB) approved November 20th

Clinical Trials: Hypotheses

• The system can be used to observe cadence changes and elevation changes • The system will be well tolerated by the patients• Threshold for detection of cadence change will vary between normal and

amputee subjects and can be incorporated into the design

Project Cost

Project FundingStage: Item Purchased: Cost:

Development (Fall 2013)

Fitbit® OneTM (x7) $700Software Development $300Subtotal: $1000

Clinical Trial(Spring 2014)

Misc. Cost per Subject $3000Promotion & Publication $1000Subtotal: $4000

Metrics

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Metric Description Target ValueReference

(See Appendix A)

Number of Steps The device will measure the number of steps the user takes over a certain period of time.

±10% of actual steps [4]

Change in cadence The software will detect changes in cadence. ±10% change in cadence

Distance The design will measure the distance the user covers in meters.

±10% of actual distance [2]

Incline/Decline The device will recognize whether the user travels over an incline or decline. 20° American

Disability Act

Data AcquisitionThe device will be able to store data over a certain

amount of time. This data will be able to be uploaded in a certain amount of time.

25000 hours Current Technology

Affordability The device should be sold to consumer below target value. <$100 Sponsor

Feedback

Path Forward

• Business negotiations for intellectual property between Fitabase and IPO• Run clinical trials in Spring 2014 (UD MEEG482)• Academic publication of clinical trials in Summer 2014• Distribution of software to other prosthetics clinics through Fitabase 2014-

2015• World Tour 2014-2015

Acknowledgments

John Horne, SponsorDr. Buckley, Advisor

Entire Senior Design Staff

Thank you for your attendance!