Evaluating Mobility Interventions in the Real World
Phase: NA
Conditions: Lower Limb Amputation, Drop Foot
Sponsor: University of Wisconsin, Madison

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RESEARCH PROTOCOL 
 
 
Evaluating Mobility Interventions in the Real World 
 
 
PI: Dr. Peter G. Adamczyk Ph.D. 
Associate Professor, Department of Mechanical Engineering, UW‐Madison. 
peter.adamczyk@wisc.edu 
 
Collaborators: Bradford Hendershot, Ph.D.; Christopher Dearth, Ph.D.; Julian Acasio, MS 
Walter Reed National Military Medical Center (WRNMMC), Bethesda, MD, USA 
 
 
 
 
Protocol Version Date: Version 1.5: 2023‐09‐21 
 
Funding Sponsor: United States Department of Defense 
 
 
NCT04275973 

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Project Summary 
 
This project is intended to test the comparative biomechanical benefits of different lower‐limb 
prostheses and orthoses using data collected over extended periods of everyday life using 
wearable sensors. We seek to improve physical health, functional activity level, independence, 
workforce participation, and mental health in persons with lower limb amputation and other 
lower‐limb impairments. We seek to study the similarities and differences in their movement 
using prostheses and orthoses with different technological features or designs. We also seek to 
develop technologies that enhance the methods for using wearable sensor technology to 
perform this type of study. 
Subjects with lower‐limb amputation, subjects who use lower limb orthoses, subjects with 
drop‐foot (including a specific group with Multiple Sclerosis), and healthy control subjects will be 
recruited in this study. Subjects of all groups will be tested for biomechanical performance and 
optionally for caloric energy expenditure during balance and locomotion tasks including standing, 
walking, running, ascending and descending stairs and ramps, walking on sloped terrain, and 
walking on uneven terrain. Subjects with amputation will use a variety of commercially available 
prostheses to test the effects of certain prosthesis properties or behaviors. The effects of 
different conditions will be assessed using both repeated‐measures experiments in a laboratory 
and long‐term repeated‐measures observational studies using data from wearable sensors. 
Subjects who use lower‐limb orthoses or who have drop‐foot will perform similar tests using 
multiple types of orthotic interventions including ankle braces and functional electrical 
stimulation devices. Subjects with intact limbs will perform tasks while wearing ordinary shoes 
to provide normative data. They may also perform tasks while wearing a prosthesis simulator 
(walking casts or leg braces that lock or circumvent the ankle, to which prosthetic feet can be 
attached) and lift shoes, in order to test the function and durability of the prostheses. Finally, 
they may perform tasks while wearing lower limb orthoses. Measurements may include body 
segment motion (from optical motion capture and/or wearable inertial sensors), ground reaction 
forces (force plates), loads in the tibial pylon of the prosthesis (pylon load cell), foot sole pressure 
(pressure‐sensitive insoles), electromyographic signals (EMG, using skin electrodes), energy 
expenditure (respiratory gas exchange), ambulatory device usage (by inertial measurement 
sensor), outdoor location (GPS), indoor location (based on wireless network signals and special 
beacons) and other measurements of movement and biomechanics. Outcomes may include 
spatiotemporal gait characteristics (e.g. walking speed, step length, step width, step time); 
motion of the body; characteristics of the paths a person traverses in everyday life; kinetic 
performance of joints and segments (force, moment, impulse, power, work); and other 
biomechanical performance measures. 

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Relationship between UW and WRNMMC: The overall project has components at two 
locations – the University of Wisconsin – Madison and Walter Reed National Military Medical 
Center (WRNMMC) – but it is not being treated as a multi‐site study. The protocol presented here 
covers experiments at UW‐Madison as well as transfer of data from WRNMMC and analysis of 
data from both sites, but it does not cover activities specific to the experiments at WRNMMC. 
This section explains the reasoning for this approach, for the sake of clarity in review. 
The WRNMMC site and the UW‐Madison site are being treated as separate studies for purposes 
of IRB approval. The reasons for this are several. First and foremost, the DOD Human Research 
Protection Office (HRPO) recommends the use of separate approval for each site in DOD‐ 
sponsored research. HRPO is required to approve the protocols at each site of any research 
sponsored by DOD, and a multi‐site study must continually maintain compatible protocols across 
all sites through this additional layer of oversight and administration. Because local IRB 
requirements can differ, HRPO recommends treating the sites as separate so the pain of resolving 
differences can be avoided. Second, the activities at the two locations (UW and WRNMMC) are 
not intended to be identical. UW‐Madison is responsible for developing wearable sensors, pilot 
testing the technology, and developing algorithms to process it, whereas WRNMMC is a data‐ 
collection site only. Third, UW‐Madison and WRNMMC are also testing different things: UW will 
perform pilot tests with different prostheses and orthoses as part of the methods development, 
for shorter time periods (1 week) and with less biomechanical testing. WRNMMC will test specific 
properties of the prostheses using longer periods (3 weeks) and more extensive in‐lab 
biomechanical testing. Because the protocols differ, they will produce separate data pools. There 
is the possibility that some portions of the data pools can be combined to yield broader results, 
but this is different from conducting a true multi‐site study. Therefore, we believe the strategy 
of treating each site separately with its own IRB approval is both convenient and correct for this 
study. 
UW‐Madison will be the primary data processing site for all portions of the study, so this 
protocol contains information on how data will be transferred between WRNMMC an UW‐ 
Madison. These procedures include coding of data at WRNMMC, and retention of the code key 
only at WRNMMC so that UW will not have access to direct identifiers. Similarly, any data 
generated at UW and shared with WRNMMC will be coded and the code key will be retained at 
UW only. UW is also the primary site and home of the project PI, so this protocol includes 
information about on‐site interaction among staff from the two sites. The purpose of such 
interaction is to allow UW personnel from UW to travel to WRNMMC to provide training on the 
use of the sensor systems, observation of the experiments on‐site at WRNMMC, and 
demonstration of the processing and data interpretation algorithms developed at UW. Staff from 
WRNMMC may also come to UW for training, observation and demonstration. 

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Part I: Overview of Potential Procedures and Outcomes 
Background and Significance 
Prostheses: 
Transtibial and transfemoral amputees require the use of ankle‐foot and knee‐ankle‐foot 
prostheses for bipedal ambulation. Prosthesis performance is a critical factor in the health and 
well‐being of persons with lower‐limb amputation. However, traditional passive prostheses, even 
modern Energy Storage and Return (ESR) prostheses and multi‐axial (MA) prostheses, are 
inadequate for producing biomimetic gait patterns across locomotor functions required for 
activities of daily living [1]. To better mimic the human lower limb, advanced prostheses have 
been developed that achieve greater adaptability to the different tasks and terrains a person 
encounters. These features include passively adapting properties such as user‐adjustable 
hydraulic damping in the ankle or knee, or actively adapting properties such as computer‐ 
controlled hydraulic damping or robotic control. The addition of these features is expected to 
improve walking and other movements, and some evidence in the laboratory indicates 
preference, improved biomechanics, and higher walking speed [2]–[9] in comparison to the 
shortcomings of existing passive prostheses [10]–[13]. However, the effects of these prostheses 
on everyday life have been difficult to measure. One recent study found strong preferences for 
prostheses with greater compliance than others, but no difference in activity as tracked using a 
step counter [14]. This discrepancy leaves a gap in clinical evidence to support prescription of the 
different designs for different persons. 
Therefore, we plan to test a variety of passive and semi‐active lower‐limb prostheses that are 
currently available in the marketplace, using more advanced wearable sensors to compare how 
different devices and features affect movement inside and outside the laboratory. We plan to 
compare movement with standard‐of‐care Energy Storage and Return (ESR) prostheses against 
movement with more advanced Passive Hydraulic Ankle (PHA) and MicroProcessor‐controlled 
Ankle (MPA) prostheses. We will evaluate outcomes associated with biomechanical variables 
such as limb loading and foot movement, including load on the prosthetic socket, stride length, 
toe clearance, and others. 
Orthoses: 
Like prostheses, lower‐limb orthoses have long been a common means of improving mobility 
for persons with a variety of impairments. One of the most common impairments is drop‐foot 
(also called foot drop), which arises from a range of neural injuries including central and 
peripheral insults, neuropathy, and trauma. Orthotic solutions to treat drop‐foot include rigid or 
elastic ankle‐foot orthoses (AFOs) and functional electrical stimulation (FES) neuro‐orthoses. But, 
as with prostheses, there is currently a lack of evidence to support prescription of one 
intervention over another in clinical practice. 
Therefore, we plan to test different orthotic treatments for lower‐limb impairment, to 

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determine how different devices and features affect movement inside and outside the 
laboratory. We plan to test standard plastic or carbon‐fiber AFOs against the alternative 
treatment, an FES stimulator that stimulates the ankle dorsiflexors, for their effects on real‐world 
movement in persons with drop foot. We will evaluate similar outcomes including toe clearance 
and gait kinematics using both devices. 
Real‐World Movement Assessment: 
As mentioned above, most information about how prostheses and orthoses affect individuals 
in their daily lives is inadequate for guiding truly evidence‐based care. Current research assessing 
outcomes and developing standards of care is based on either (i) focused, laboratory‐based 
studies, or (ii) low‐resolution estimates of activity level outside the laboratory, such as step 
counts and self‐reported user experience [14]–[17]. Both approaches have drawbacks that make 
them inadequate for accurately assessing the effects of interventions on outcomes. Laboratory 
tests measure only a few movements, at a very specific point in time, often before individuals 
develop stable adaptations to new devices or conditions. Step count approaches have minimal 
information (only step count in e.g. 1‐minute intervals), can be heavily influenced by external 
factors like work or social responsibilities unrelated to any interventions, and are shown to be 
insensitive to changes in prosthetic device properties. Self‐reported longitudinal experience is 
notoriously inaccurate and subject to bias. 
Therefore, we are developing methods for using a person’s own behavior in daily life as a 
replacement for controlled laboratory research protocols. We will apply these new methods to 
evaluate the differences in behavior among specific biomechanical devices such as prostheses, 
orthoses, or types of footwear. The potential benefits of this approach include eliminating the 
need for laboratory protocols in some instances, and improving the ecological validity of data 
used to determine the benefits of different treatments, due to recording during unsupervised 
real‐world movements. 
The scientific approach is to evaluate the statistical differences among aggregated samples of 
movements on frequently repeated paths in everyday life, under different experimental 
conditions (such as different prostheses, orthoses or shoes). We will track a person’s movements 
outside and inside buildings using wearable inertial sensors, environmental sensors (e.g., 
barometric pressure, temperature, humidity), and location sensors (e.g., GPS, computer network 
signals, dedicated beacons). We will identify specific paths (sidewalks, hallways, stairways, 
corners, etc.) that are frequented by an individual. We will identify each bout of movement along 
these paths and build sets of “comparable bouts” on the same path across multiple days and 
experimental conditions. We will repeat this procedure for multiple different devices and 
compare the effects of these devices on habitual movement. 
Project Goals: 
The immediate goals of this project are (i) to compare the effects of different types of features 

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in lower limb prostheses and orthotic solutions; and (ii) to develop methods for analyzing the 
effects of mobility devices on locomotion in real‐world environments. 
Aims 
Aim 1: 
To develop methods for using wearable sensors and long‐term monitoring to assess changes in 
gait due to different mobility interventions, and to study the effects of different interventions 
using these techniques. 
Aim 2: 
To compare the effects of different features of prosthetic feet on movement quality in everyday 
life. 
Aim 3: 
To compare the effects of different orthotic treatments on movement quality in everyday life. 
 
 
Study Objectives 
Primary objective 
To determine the comparative biomechanical benefits of prosthetic foot‐ankle systems with 
different features to persons with lower‐limb amputation. 
Secondary objectives 
To determine the comparative biomechanical benefits of different orthotic solutions to persons 
with drop‐foot. 
Tertiary objective 
To perfect methods for collecting and analyzing data from wearable sensors to compare the 
benefits of different conditions on everyday movement. 
 
Study Outcomes 
Primary outcome 
The primary outcome is biomechanical gait function, as measured through gait metrics such as 
limb and joint movement patterns and foot placement variability (kinematics), and joint and 
prosthetic socket loads and joint power production (kinetics). 
Secondary outcome 
The secondary outcome is behavioral gait function, as measured from preferred walking speed, 
stride count, breadth and perceived ease of locomotor activities, and reports of inconvenience, 
pain and discomfort. 
 
Research Design and Methods 

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In this protocol we will perform short‐term laboratory and long‐term real‐world locomotion 
testing with a variety of commercially available lower limb prostheses and commercially available 
orthotic solutions for drop‐foot, with emphasis on using wearable sensors to compare 
biomechanical performance with different devices. 
Subjects will perform testing inside the laboratory (“lab testing”), outside the laboratory (“field 
testing”) on and near the campus of UW‐Madison, and/or extended testing in a home and 
community environment (“take‐home testing”) to evaluate different aspects of device function. 
Lab testing may consist of standing (on one or both legs), walking (at various speeds, forward and 
backward), and running (from running in place to a fast jog) trials, performed on a standard 
treadmill, an instrumented split‐belt treadmill, a moving treadmill with virtual‐reality surround 
screen, on ramps, on stairs, and/or on the floor. Measurements will be made using standard 
biomechanical measurement tools such as motion capture, wearable motion sensors, force 
transducers, pressure insoles, electromyographic electrodes, treadmills, and respiratory gas 
sampling equipment. Field testing may include standing and walking trials, conducted indoors 
and outdoors, on level ground, uneven ground, slopes, and stairs, as well as level running. Take‐ 
home testing will consist of wearing one or more different prostheses, orthoses, or types of 
footwear, together with wearable sensors to evaluate their function, for periods ranging from 
hours to weeks of everyday life. 
 
 
Figure 1: Examples of prostheses that may be compared in the 
experiment: energy storage‐and‐return prostheses (ESR, left); ESR with 
passive hydraulic ankle (PHA); and ESR with microprocessor‐controlled 
ankle (MPA). Examples shown are Endolite Esprit, Echelon, and Élan. 
Specific prostheses from multiple manufacturers will be chosen in the 
course of the research. 
Experiments will use standard commercially available prostheses for persons with lower‐limb 
amputation. Specific prostheses will be determined at the time of the study, but they will include 
prostheses that are fully passive such as energy storage‐and‐return (ESR) feet, ESR feet with 
mobilized ankles such as passive hydraulic ankles (PHA), and ESR feet with microprocessor‐ 

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controlled ankles (MPA). Examples from one manufacturer (Endolite) are shown in Figure 1. A 
separate branch of the study will use multiple presecribed prostheses that an individual already 
possesses – specifically a daily‐use prosthesis, a running‐specific prosthesis, and any other 
prostheses (including but not limited to activity‐specific prostheses). For orthosis users, standard 
commercially‐available orthoses or standard‐of‐care custom orthoses will be used, as well as a 
standard commercially‐available electrical stimulation neuro‐orthoses (BioNess –Figure 2). For 
persons without impairment, different footwear will be used. Each person will use two or more 
different prostheses or orthoses in the lab and in periods of one to three weeks of everyday life. 
We will perform laboratory testing at the beginning and end of the period using each device, 
except in the cases of individuals using their own devices whose schedules or locations 
necessitate off‐site installation (no lab testing for these individuals – they will complete the take‐ 
home portion of the study only). For each device, we will perform standard gait and movement 
analysis. During field testing and take‐home testing, participants’ locations and motions will be 
recorded with a combination of global positioning system (GPS), wearable inertial measurement 
unit (IMU), Bluetooth and Wifi network sensors. During take‐home testing, data will be recorded 
continuously during all waking hours when the participant uses the sensors. Unimpaired subjects 
may also be invited to participate in the take‐home study to provide normative data with 
different types of footwear. Take‐home portions of the study will last at most 10 weeks. Subjects 
in the off‐site installation group will only perform everyday‐use testing, in which wearable 
sensors on their existing prostheses (and potentially cell‐phone GPS) log data while they use each 
of their prostheses. 
 
 
Figure 2: Orthotic drop‐foot aids for potential use in the experiment: an 
ankle‐foot orthosis (left), BioNess FES Neuroorthosis (right). The Bioness FES 
device senses leg motion and stimulates the peroneal nerve during swing 

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phases of gait, causing the dorsiflexor muscles to lift the foot for improved 
ground clearance. 
Biomechanically intact persons will perform normal locomotion activities such as standing, 
walking and running, while standard and novel biomechanical measurements are taken. The 
activities may include some or all of the following: 
• Standing still, with eyes open or closed, on flat or sloped surfaces that are stiff 
(normal) or soft. These standing activities may be performed on standard force 
plates or on a force plate that estimates stability from characteristics of the ground 
reaction force signals under the feet and moves the surface and a visual surround to 
perturb balance. 
• Walking at a range of speeds, forward or backward, on flat, uphill, downhill, or side‐ 
hill surfaces, or stairs. Surfaces may include indoor and outdoor ground, and/or an 
instrumented treadmill that measures ground reaction forces under both feet. 
• Running in all the same conditions as walking. 
• Performing any of these activities barefoot or with various shoes or boots. 
• Performing any of these activities using "prosthesis simulators" on one or both legs. 
Prosthesis simulators are designed to allow an intact person to use a foot‐ankle 
prosthesis by holding the natural foot out of the way. 
• Performing any of these activities spontaneously while wearing long‐term 
monitoring sensors in everyday life. 
 
Persons with lower‐limb amputation will perform all the same tests described above in 
biomechanically intact individuals, but using a variety of commercially‐available lower‐limb 
prostheses. The prostheses may be of many kinds exhibiting different behaviors and properties, 
including but not limited to: 
• Standard wood, plastic and foam prostheses. 
• Carbon fiber or fiberglass prostheses with high energy storage and return. 
• Prostheses with passive or manually‐adjusted mechanisms to alter properties such 
as stiffness or damping. 
• Prostheses with microprocessors that control their motion or properties such as 
stiffness, damping or joint angle through active adjustment. 
• Running‐specific and other activity‐specific prostheses. 
Running tests will be limited to those who are already habitual runners. 
 
Persons with drop‐foot will perform all the same tests as those with lower‐limb amputation, 
using different orthotic solutions. The orthotic solutions may include braces of various kinds as 

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well as neuro‐orthoses, including but not limited to: 
• Standard orthoses, made of plastic, fiberglass or carbon fiber, with or without 
hinges. 
• Custom orthoses with special structural features such as custom stiffness, novel 
support surfaces, or energy return properties. 
• Functional electrical stimulation (FES) devices that stimulate the peroneal nerve to 
activate the ankle dorsiflexor muscles. 
Orthoses may be designed and built by orthotists associated with the study team according to 
standard clinical practices, or they may be purchased off‐the‐shelf according to standard clinical 
prescription practices. Running tests will be limited to those who are already habitual runners. 
 
The subgroup of persons with Multiple‐Sclerosis and drop‐foot will perform all procedures as 
described for persons with drop‐foot, but enrollment will be restricted to MS patients. 
 
All participants may be subjected to a variety of measurements: 
• Weight and size measurements for scaling biomechanical models. 
• Use of skin‐mounted reflective markers for motion capture in a research‐grade 
motion laboratory. 
• Measurements of strength such as manual muscle testing with or without 
dynamometry. 
• Measures of gait and balance function 
• Force measurements under the feet using in‐ground force plates, balance plates, 
load cells installed in a treadmill, or pressure‐sensitive shoe insoles. 
• Measurements of muscle activity through skin electrodes. 
• For persons with amputation, force measurements from a load cell installed in the 
prosthetic pylon. 
• Miniature inertial sensors (accelerometer/gyroscope/magnetometer) systems 
mounted on the feet and other body segments. 
• Environmental sensors (temperature, barometric pressure, relative humidity, etc.) 
mounted on the leg 
• Tracking of assistive device usage via inertial measurement sensors attached to the 
subject’s ambulatory assistive device(s) 
• 
Location tracking through a global positioning system (GPS) receiver or cell phone 
app, either carried or worn on the body 
• 
Supplementary indoor tracking system, such as a Bluetooth beacon (to be placed in 
a frequented location by the participant), or a Wi‐Fi signal‐based tracking app on a 
cell phone or other body‐worn computer 

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• Measurement of respiratory gas exchange (oxygen consumption, carbon dioxide 
production) during movement to estimate energy expenditure. 
• Voice recordings to capture key comments subjects make about the devices or to 
record events that occur during daily life. 
o The voice recordings are necessary as an alternative to written records so 
that for any event a firm time stamp can be established, enabling analysis of 
the event according to the time‐stamped movement records. Written 
records are also known to be unreliable. 
o Recordings are limited to notable events related to this mobility study, such 
as: any trips, slips, falls, or losses of balance; locomotion on unusual terrain; 
activities of special note such as running or participation in sports; and any 
malfunction of the other sensors. 
• Photographs and videos for analysis and presentation 
o Non‐identifiable images will be recorded as a record of the experiment. 
o Identifiable images will be recorded only with specific consent for identifiable 
images. 
 
Subject identification and Recruitment 
 
Target Population and Enrollment 
The target enrollment is 20 persons with transtibial amputation and 10 persons with drop‐foot 
at UW‐Madison, and up to 20 healthy controls to test the methods. Additional participants with 
transfemoral amputation (up to 10) may also be enrolled at UW‐Madison. Additional participants 
with transtibial and transfemoral amputation will be recruited at the remote site for a separate 
data pool (Walter Reed National Military Medical Center, WRNMMC). All subjects will be 18‐75 
years old, representing the main target population for whom these devices could improve daily 
life. 
We will recruit subjects following inclusion and exclusion criteria mentioned below. 
Target Populations: 
• The first target population is persons with lower‐limb amputation who use prostheses 
for ambulation. 
• The second target population is persons with drop‐foot. 
o A targeted subset of the drop‐foot population will be persons with Multiple 
Sclerosis and currently drop‐foot. 
 
Inclusion: 
Target Populations: 

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• Subjects will be age 18‐75 years at time of enrollment. 
• Subjects with amputation must have used a prosthesis for more than 6 months, and 
wear it for at least 8 hours per day. 
• Subjects must be more than 6 months past their most recent surgery (if any). 
• Subjects must be free of musculoskeletal and cardiovascular conditions that would limit 
their ability to safely complete testing. 
• Subjects should consider themselves in good health; be able to wear their prostheses or 
orthoses all day long; be able to perform all of their activities of daily living (ADL) with 
their prostheses or orthoses as appropriate, have a comfortably fitting functional 
prosthesis (if applicable) that does not cause any skin problems; and have a stable 
residual limb (or impaired limb). 
• Subjects may use a narrow‐base cane (single point, narrow tripod base, etc.) as an 
ambulatory aid but not a small‐base quad cane, wide‐base quad cane or walker. 
• Subjects must be able to walk with their prostheses or orthoses for 30 minutes (total) 
and stand for 30 minutes (total), in individual bouts of at least 7 minutes, without 
becoming fatigued, feeling dizzy, having chest pain or shortness of breath, or 
experiencing claudication symptoms. 
• Subjects most report an estimated average daily walking time of at least 45 minutes 
outside of the home. This does not need to be continuous and considers walking for all 
purposes. 
• Subjects involved in running tests must be able to run for 30 minutes (total) in bouts of 
at least 6 minutes, without becoming fatigued, feeling dizzy, having chest pain, or 
experiencing claudication symptoms. 
• Subjects must have no known cognitive disability. 
• Subjects must be fluent in spoken and written English. 
• Running portions of the study will be limited to subjects who self‐report regular 
engagement in recreational or competitive running. 
• Subjects in the branch that uses only their own prostheses must have at least a daily use 
prosthesis and a running‐specific prosthesis; additional prostheses may also be included. 
 
Control Subjects: 
• Ages 18‐75 years 
• Subjects should consider themselves in good health, and be able to perform typical 
activities of daily living (ADL). 
• Subjects may use a narrow‐base cane (single point, narrow tripod base, etc.) as an 
ambulatory aid but not a small‐base quad cane, wide‐base quad cane or walker. 
• Subjects must be able to walk for 30 minutes (total) and stand for 30 minutes (total), in 

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individual bouts of at least 6 minutes, without becoming fatigued, feeling dizzy, having 
chest pain or shortness of breath, or experiencing claudication symptoms. 
• Subjects involved in running tests must be able to run for 30 minutes (total) in bouts of 
at least 6 minutes, without becoming fatigued, feeling dizzy, having chest pain, or 
experiencing claudication symptoms. 
• Subjects must have no known cognitive disability. 
• Subjects must be fluent in spoken and written English. 
 
Multiple Sclerosis group: 
• For the specific subgroup targeting Multiple Sclerosis, subjects must have a clinical 
diagnosis of Multiple Sclerosis and a clinician must determine they are experiencing foot 
drop. 
• Subjects must be able to comfortably wear and ambulate with both study devices with 
effective management of foot‐drop, without significant discomfort 
• Subjects must be able to perform all of their activities of daily living (ADL) with only 
minimal use of ambulatory aids. Subjects may use a narrow‐base cane (single point, 
narrow tripod base, etc.) as an ambulatory aid in any amount. Use of more 
comprehensive ambulatory aids (e.g. a small‐base quad cane, wide‐base quad cane or 
walker) must be limited to no more than 20% of their walking time when not at home. 
Individuals who do use an assistive device occasionally should report a threshold for use 
of greater than 100 feet, i.e., they are unlikely to use their device unless they anticipate 
ambulating greater than this distance. 
 
Exclusion criteria: 
Target Populations: 
• Allergy to electrode gel, surgical tape and metals. 
• Subjects who currently use the Bioness L300 Go or similar neuro‐orthoses or use a 
carbon fiber ankle‐foot orthosis for more than occasional use at the time of the study 
will be excluded to avoid biasing results for one device or the other. Occasional use for 
the purpose of this study is defined as more than 20% of walking time when not at 
home. Subjects with past experience who are not currently using these devices will be 
eligible. 
• Subjects enrolled in physical therapy or other rehabilitative care for treatment of gait, 
balance, or lower extremity strength or coordination at the time of the study will be 
excluded to avoid confounding effects from therapy and device‐based management of 
their condition. 
• For the orthotics study, subjects with peripheral neuropathy impacting control of the 
tibialis anterior muscle via the peroneal nerve will be excluded. 

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• Subjects under treatment for infectious diseases will be excluded from the study. 
• Women who are pregnant or planning to become pregnant during the course of the 
study will be excluded. 
• Symptomatic musculoskeletal conditions that prevent unaided walking, such as back 
pain or knee arthritis. 
• Cardiovascular conditions that make moderate exercise unsafe, including (but not 
limited to) history of angina, peripheral vascular disease, congestive heart failure, 
history of myocardial infarction, and history of stroke. Potential participants will be 
excluded if they self‐report that a physician has told them to avoid moderate exercise. 
• History of chest pain, shortness of breath, or claudication symptoms during ambulation 
• History of significant neuropathy with altered balance 
• History of serious residual limb pain or phantom limb pain within the past six months. 
• History of chronic skin breakdown. 
• Inability to perform the tasks involved in the study. 
• Age under 18 or over 75 years at time of enrollment. 
 
Control Subjects: 
• Allergy to electrode gel, surgical tape and metals. 
• Subjects under treatment for infectious diseases will be excluded from the study. 
• Women who are pregnant or planning to become pregnant during the course of the 
study will be excluded. 
• Symptomatic musculoskeletal conditions that prevent unaided walking, such as back 
pain or knee arthritis. 
• Cardiovascular conditions that make moderate exercise unsafe, including (but not 
limited to) angina, peripheral vascular disease, congestive heart failure, history of 
myocardial infarction, and history of stroke. Potential participants will be excluded if 
they self‐report that a physician has told them to avoid moderate exercise. 
• Inability to perform the tasks involved in the study. 
• Age under 18 or over 75 years at time of enrollment. 
 
Persons in status relationships with members of the study team may be included in any of the 
groups. Recruitment of those with a status relationship may occur through indirect methods 
(posted flyers/ads and mass emails), or when these individuals learn about the study in the 
course of their participation in lab activities and/or interaction with members of the lab and study 
team. If these persons wish to enroll, the process will be handled by a study team member who 
does not have a position of influence over them. If the initial discussion involves the PI, the PI will 
state that he does not intend any pressure to participate, that the decision to participate is each 

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individual's alone, that there will be no negative consequences for non‐participation, and/or 
similar statements, and will refer the prospective participant to another member of the study 
team for the rest of the recruitment, enrollment, and consent process. The Informed Consent 
process will be performed by a member of the study team who is not in a position of influence 
over the potential subject. 
HIPAA compliant (REDCAP) email and/or text‐messaging, depending on subject preference, will 
be used for efficient and consistent communication with participants. Participants will receive 
contacts from the study team with reminders regarding completing the patient‐reported 
outcomes and upcoming study visits. 
 
Subject Identification: 
• Clinicians (rehabilitation physicians, physical therapists, orthotists and prosthetists) 
involved in the care of patients may identify potentially eligible patients as they come to 
clinics for routine visits. 
• Many potential participants for this research are well‐known to their clinicians, and 
communicate with them regularly outside of regular visits. Clinicians may identify these 
subjects from memory. 
• Recruitment flyers may be posted at different locations such as the UWHC; the School of 
Medicine; UW Orthotics and Prosthetics clinic; UW libraries; the University Station 
Clinic; St. Mary’s hospital; Meriter hospital; Madison public libraries; prosthetics and 
orthotics clinics in the Madison, WI area and other areas of southern Wisconsin and 
northern Illinois; amputee or mobility impairment support group locations, and on the 
web page of the UW BADGER Lab (http://uwbadgerlab.engr.wisc.edu). 
• Recruitment emails may be sent to support group lists to advertise the study to their 
members (for subject self‐identification). Emails to support groups will be sent no more 
than once per three months, always with the permission of the group mailing list 
moderators [email text provided in IRB application]. 
• A posting will be listed on the MS Society website for clinical trials: 
https://www.nationalmssociety.org/Research 
 
Subject Recruitment: 
• Clinicians throughout the United States (rehabilitation physicians, physical therapists, 
orthotists and prosthetists) involved in the care of patients may hand recruitment flyers 
to eligible patients and discuss the study with them [recruitment flyer attached to IRB 
application]. 
• Many potential participants for this research are well‐known to their clinicians, and 
communicate with them regularly outside of regular visits. Clinicians may tell these 

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potential participants about the study by voice during these routine phone calls, or 
include basic study information in email communications they would normally 
undertake, or make a dedicated phone call or send a dedicated email message with 
basic study information. [email template attached to IRB application]. Alternatively, 
clinicians may send a physical letter to potential participants' mailing addresses. 
[Template letter attached to IRB protocol ‐ "Individual Participant Recruitment Letter 
Template"]Recruitment flyers may be posted at different locations such as the UWHC; 
the School of Medicine; UW Orthotics and Prosthetics clinic; UW libraries; the University 
Station Clinic; St. Mary’s hospital; Meriter hospital; Madison public libraries; prosthetics 
and orthotics clinics in the Madison, WI area and other areas of southern Wisconsin and 
northern Illinois; amputee or mobility impairment support group locations, and on the 
web page of the UW BADGER Lab (http://uwbadgerlab.engr.wisc.edu). 
• Potential participants contacted by clinicians using these first two methods may be 
asked by the clinician to give permission to share their contact information with other 
members of the study team. If they give permission, the clinician will pass on their 
name, phone and/or email to one of the other approved members of the study team, 
who will reach out directly to the potential participant. 
• Recruitment emails may be sent to support group lists to advertise the study to their 
members (for subjects to volunteer), with the permission of the group mailing list 
moderators [email text provided in IRB application]. Emails to support groups will be 
sent no more than once per three months, always with the permission of the group 
mailing list moderators [email text provided in IRB application]. 
• With permission of support group leaders, members of the study team may visit local 
support group meetings either virtually or in‐person to present basic information on this 
study which is included in current recruitment materials, address any questions from 
persons in the group, and recruit participants. 
• Volunteers (with or without prostheses/orthoses) may be recruited through flyers 
posted across the UW campus and downtown Madison. Flyers will only be posted where 
approved by the appropriate authority. [Sample flyer is attached] 
• Volunteers (with or without prostheses/orthoses) may be recruited through an email 
blast to the UW community, through the Division of Information Technology (DoIT). 
[Sample text of the email is attached.] Emails through DoIT will be sent no more than 
once per year. 
• Volunteers (with or without prostheses/orthoses) may be recruited through word‐of‐ 
mouth. Study team members approved to perform recruitment may mention the study 
and/or hand out recruitment flyers to friends, family, neighbors, classmates, and others. 
 
Participants responding to the recruitment flyer will be contacting a member of the study team 

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approved to perform subject recruitment, enrollment and consent. This study team member will 
describe the study briefly to each potential participant who responds to these recruitment 
methods. The subject will be screened and recruited during the first phone call or meeting, or at 
a later time. Recruitment and screening will be performed according to a screening script 
[attached] by members of the study team approved for these activities. Screening materials for 
persons who do not enroll in the study will be destroyed, unless the person gives permission to 
be contacted for future studies. If the respondent expresses willingness to participate in the study 
or to be contacted for future studies, his/her name, contact information, and potential group 
(prosthesis user, orthosis user, control) will be added to a list of interested potential participants. 
This list is for limited use by the study team for prosthetics and orthotics‐related studies only. 
During the telephone screening, the following information will be collected directly into ICTR 
REDCap as appropriate: name, preferred name, address, home phone number, mobile phone 
number, email address, age, birthdate, gender, height, weight, past medical history, past 
surgical history, and the answers to the telephone screening questionnaire. Electronic files will 
be removed from ICTR REDCap ten years following study completion. 
 
Consent or Assent: 
Alteration of Informed Consent: 
We will request a waiver of written documentation for consent so that we may obtain oral 
consent for: 
1. Retaining the notes taken during the telephone screening for eligibility and recruitment 
for future studies 
2. Communicating via email and text messaging for study‐related purposes 
During a telephone screening for potential participants, we will obtain oral consent to retain 
the notes taken during the screening for up to 10 years for the purpose of inviting them to 
participate in future studies, and to communicate with them via email and/or text messaging 
for study‐related purposes, which includes sending emails and/or texts that contain links to 
ICTR REDCap that will allow them to complete study‐related questionnaires throughout the 
duration of the study as well as remind subjects of upcoming appointments. 
 
Justification of Altered Consent: This study involves completing a telephone screening, 
questionnaires, and participating in clinical assessments and interventions that are common 
and currently in use in clinical practice at UW Health. These activities are similar to and of no 
greater risk than activities of daily living or that would be encountered during a standard clinic 
examination. The altered consent increases the feasibility of conducting this project (and future 
projects) by simplifying recruitment. These procedures also reduce the time commitment 
required of participants. This waiver would not adversely affect the rights and welfare of 
subjects. 

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Written Informed Consent: A copy of the informed consent document will be provided to 
potential participants after screening via e‐mail or U.S. mail according to participants 
preference. Subjects will be asked to return a signed copy of written consent either via a 
scanned copy emailed to the study team or a signed copy sent to the study team through U.S. 
mail. Alternatively, subjects can provide Written Informed Consent through REDCap. 
 
The informed consent will be cosigned prior to the start of the first data collection visit at the 
BADGER Laboratory. Each consented participant will be reminded that s/he may withdraw from 
the study at any time, for any reason, without any impact on his/her ongoing care. 
 
Subject Compensation: 
• On‐site testing studies (in‐lab or out‐of‐lab) with no take‐home component: 
o Subjects in the Patient groups (users of prostheses or orthoses) will be paid $20 
per hour to compensate for their time and travel expenses. 
o Subjects in the Non‐patient group will be paid $10 per hour for laboratory 
sessions to compensate for time and travel expenses. 
o Subjects will be reimbursed for parking expenses (or a parking voucher will be 
provided). 
• Long‐term monitoring studies (take‐home studies): 
o Subjects in the Patient groups (users of prostheses or orthoses) will be paid up to 
$450 total for participation, including on‐site portions: 
 Up to $360 will be paid on a pro‐rata basis based on how much of the 
study the subjects complete (at $40 per week for Orthosis users, $90 per 
week for Prosthesis users). 
 $90 will be paid for completion of the full study. 
o Subjects in the Non‐patient group will be paid up to $150 total for participation, 
including on‐site portions: 
 Up to $100 will be paid on a pro‐rata basis based on how much of the 
study the subjects complete (at $25 per week). 
 $50 will be paid for completion of the full study. 
o Subjects will be reimbursed for parking expenses (or a parking voucher will be 
provided). 
o Payment will be processed only after all take‐home equipment is returned. 
 
Privacy and Confidentiality 
Study procedures involving protected health information (e.g. the Consent process and 
background information gathering) will be performed in private rooms, by staff that have 

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received HIPAA training. Subjects may choose not to answer any questions that make them 
uncomfortable or that they feel violate their privacy. All subject data will be identified by a 
subject number. 
Study data files will consist of hand notes from study personnel and computer data files. Most 
patient‐reported outcome questionnaires will be completed on‐line through a secure connection 
to ICTR REDCap, otherwise paper will be utilized during in‐person visits. Hand notes and paper 
questionnaires will be scanned to electronic files and the hard copies will be destroyed. All these 
files will be identified only by the subject number (no personally identifying information will be 
associated with them). Coded data files will be available to all study team personnel on a need‐ 
to‐access basis. Coded data files will be stored on a password‐protected computer in the PI's 
laboratory or on HIPAA compliant servers such as ICTR REDCap. Coded files will also be 
transferred to other password‐protected computers used by team personnel for data processing 
and publication. Subject information will not be disclosed to anyone who is not personnel on this 
study team without the written permission of the subject. To the extent permitted by law, subject 
identity and participation in this study will remain confidential. 
Code key files (consent forms) will be stored only in hard copy, in a locked cabinet in the PI's 
locked laboratory or office (Department of Mechanical Engineering, 3034 or 3039 Mechanical 
Engineering Building) or in locked offices of the collaborating site at Walter Reed National Military 
Medical Center (for WRNMMC subjects). Each site (UW and WRNMMC) will retain the only copy 
of the code key for data collected at that site. Codes will be destroyed no more than 5 years after 
the completion of the study or the date of final data publication, whichever is later. De‐identified 
data (de‐identified after the codes are destroyed) will be kept indefinitely on computers in the 
laboratory or on servers, and used by the study team to address new scientific questions. De‐ 
identified data may be published to public repositories for analysis by other researchers. 
We will take precautions to protect subject information from a breach of confidentiality with 
the use of electronic security measures (e.g., passwords). Additionally, paper files will be stored 
in a locked cabinet when not in use. Subject information will not be disclosed to anyone who is 
not key personnel on this study without the subject’s written permission. To the extent permitted 
by law, subject identity and participation in this study will remain confidential. 
Collection of sensitive information is limited to the amount necessary to achieve the aims of 
the Research. This information will be collected on a Health Questionnaire with additional notes 
through conversation as appropriate. We will record name, sex, date of birth, contact 
information, race and ethnicity, and relevant medical information (e.g. etiology of 
amputation/injury; time since amputation/injury; specifications of the prescribed device(s); 
functional K‐level; underlying conditions; comorbidities; musculoskeletal, neurological or 
cardiovascular problems; vision or balance problems; problems with sensation e.g. neuropathy). 
These data are necessary to categorize results with respect to different subgroups of the target 

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population. For subjects without prostheses or orthoses, similar information will be collected, 
without the condition‐specific aspects. 
Data collected during the study itself will not be personally identifiable except through the code 
key, which will be kept separately under access control. It may include 3D locations of motion 
capture markers, measurements of contact force with the ground and other objects, 
electromyographic (muscle activity) signals, motion data from wearable sensors, respiratory gas 
exchange rate (e.g. oxygen consumption), and other common biomechanical signals. 
One exception to the use of coded data will be identifiable photos or videos, for which explicit 
authorization will be requested during the Informed Consent process (authorization to record 
and to display identifiable images). Identifiable images will not be recorded if this authorization 
is withheld. 
The other exception is location data, recorded as part of the long‐term monitoring studies. 
These data include interpretable information about home, workplace and other frequently 
visited locations, which could potentially re‐identify the participant. These data will be handled 
with special care, for example by obfuscating the location data prior to publication (e.g. moving 
it to a different part of the Earth). Specific procedures outlined in the “Risk to Privacy” section 
(below). 
Location data may be tracked with a cell phone app. Such apps present a risk to privacy and 
confidentiality because the phone vendor and app vendor may both gain some information about 
the user. We will attempt to mitigate this risk by using custom apps or by creating accounts with 
impersonal credentials rather than the participant’s personal information. However, perfect 
privacy with a cell phone is impossible, so participants will be informed of the risk and asked to 
accept or decline participation. 
Study procedures involving field testing will take place in public spaces, including inside 
academic buildings, in the location of sensor installation (for those installed outside the lab) 
outdoors on the UW‐Madison campus, and anywhere the participant chooses to go in long‐term 
monitoring studies. These procedures involve the possibility of being recognized by bystanders. 
Subjects will be advised of this risk and will have the opportunity to accept it or decline 
participation during the Informed Consent process, including the elevated risk from having 
sensors installed in a public space. For patients, the use of lower‐limb prostheses or orthoses is 
generally visible already, so the risk to privacy is comparable to ordinary daily life. 
Only individuals involved with the study will have access to Protected Health Information (PHI), 
all identifying information, and all identifiable datasets, which will all be stored in locked cabinets 
in the PI’s laboratory or office, or on password protected computer systems. 
Data transmission among sites will be through secure, HIPAA‐compliant Box folders or HIPAA‐ 
compliant storage through the UW Campus Computing Initiative or a DOD‐authorized HIPAA‐ 

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compliant data transfer system. These systems will be accessible only to study team members 
and designated collaborators. 
 
Study Procedures ‐ General 
Lower‐Limb Biomechanics with Prostheses and Orthoses: 
This study involves: (1) testing movement performance while wearing different lower limb 
prostheses, orthoses, or footwear, and (2) developing methods for evaluating this performance 
using wearable sensor data recorded during everyday life. Devices to be tested include lower‐ 
limb prostheses, tested with the customary prosthetic socket (for amputees) or prosthesis 
simulators (for intact subjects), as well as standard orthoses (for persons with drop‐foot) and 
footwear (for intact subjects). Tasks may include: sitting, standing, walking and running at various 
speeds on level ground or treadmills, and walking up/down stairs and at inclines/declines and 
across slopes. Testing will be conducted in the UW Biomechatronics, Assistive Devices, Gait 
Engineering and Rehabilitation Lab (UW BADGER Lab), the UW Neuromuscular Biomechanics Lab 
(UWNMBL), UW McClain Athletics Lab, or the UW Research Park Clinic. In the lab, subjects will 
perform locomotor tasks over ground or on a moving treadmill. Some subject testing may be 
conducted in a normal everyday environment outside of the lab. Outside of the lab, subjects will 
perform some locomotor tasks over ground. These locomotor tasks will be tasks that they 
normally encounter in their everyday lives, such as walking and running in buildings and outdoors 
on pavement, grass, dirt, gravel, and other everyday surfaces such as stairs and ramps. 
 
Individual laboratory testing sessions will last no more than 5 hours. Sessions with patient 
groups will require no more than 90 minutes of physical activity during each session. Sessions 
with non‐patients will require no more than 120 minutes of physical activity. Activity limits will 
be adjusted to respect any more stringent recommendations reported by specific subjects. 
Devices: 
Subjects with amputation will use their own prostheses and/or standard commercially available 
prostheses (Figure 1). No experimental devices will be used in this study. 
Subjects with drop‐foot will use the Bioness L300 Go functional electrical stimulation neuro‐ 
orthoses or the Thuasne SpryStep, a standard carbon fiber orthosis (Figure 2). 
To test prostheses on unimpaired subjects, these subjects will wear a “prosthesis simulator” 
system. One version is prosthesis simulator boots – rigid walking boots that immobilize the ankle 
similar to ski boots, with a special attachment on the bottom surface to simulate walking with a 
prosthetic foot. These experimental simulator boots have been used in past human research by 
the PI and others [18]–[21]. Other variations of a prosthesis simulator system may also be used, 
such as versions based on leg braces that circumvent the ankle rather than immobilizing it. 

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Unimpaired subjects may also test standard AFO’s by wearing them with standard footwear. All 
standard devices will be purchased off‐the‐shelf. Standard custom orthoses (e.g. AFO’s 
constructed to fit individual patients according to standardized procedures) will be constructed 
at the UW Health Orthotics and Prosthetics Clinic. 
Biomechanically unimpaired subjects may also test wearable sensors through comparisons of 
different kinds of footwear. 
The sensors used in the study have no action that could affect the subject, and their effects are 
not under investigation. They are for instrumentation only, and therefore are not investigational 
devices. 
 
Instructions: 
We will provide subjects with instructions for using the sensors and test devices 
(prostheses/orthoses/footwear). Information will include: how to turn on the sensors and test 
devices; how to plug in and charge any that need power; when they should or should not be used; 
how to keep them clean; what to do if certain problems arise; and contact information for the 
study team members whom subjects should contact if they have any questions or problems with 
the devices. 
 
Analyses: 
Movement analyses may include measurements of movement kinematics, forces acting on the 
limbs, and muscle behavior (electromyography, EMG). Movement kinematics may be recorded 
using a passive motion capture system with retroreflective markers mounted to various 
segments of the body, on the skin or over tight‐fitting clothing. Body‐mounted 
electrogoniometers and/or inertial sensors may be also used to record three‐dimensional 
movement. For field tests, global positioning system (GPS) and/or bluetooth, Wi‐Fi or other 
electronic positioning systems may record the participant’s location for characterization of 
activities. Ground reaction forces will be recorded using force plates, a split‐belt force treadmill, 
a load cell mounted in the prosthetic pylon, and/or pressure‐sensitive shoe insoles. 
Electromyography (EMG) measurements will be made with electrodes placed on the skin surface 
to record signals from lower‐extremity muscles. If EMG measurements are desired from the 
residual limb muscles of persons with amputation, special sockets will be fabricated by a certified 
prosthetist to accommodate the electrodes [22]. 

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Figure 3: Example of a wearable respiratory gas analysis system (COSMED 
K5). Such a system may be used to estimate energy expenditure through 
indirect calorimetry. 
During some locomotor tasks, we may also monitor the metabolic energy cost of locomotion 
using measurements of respiratory gas exchange (indirect calorimetry). Subjects will wear a 
mouthpiece so that we can sample their inspired and expired breath gases. These gases will be 
analyzed with a metabolic cart or a light‐weight backpack‐mounted gas analysis system to 
determine oxygen consumption and carbon dioxide production (e.g. Figure 3). 
 

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Figure 4: CAREN moving treadmill system. Such a system will be used at 
WRNMMC to compare laboratory vs. real‐world data. A similar system with 
a stationary treadmill may be used at UW‐Madison. 
During some experiments, participants will walk on a treadmill, with (Figure 4) or without a 
virtual‐reality surround screen. This test will allow comparison of standard laboratory data 
against data collected in a real‐world environment. 
During some experiments, we may also test static and dynamic balance and the coordination 
of sensorimotor systems using the Neurocom SMART Balance Master system [23] (Figure 5). This 
system is approved to perform a range of test on adults, all related to standing balance, including 
conditions that (a) move a visual surround; (b) tilt the standing surface; (c) introduce soft or firm 
foam under the feet; and/or require the subject to lean toward his/her limits of stability. This 
system includes an overhead harness that will always be used to prevent falls. 
 
Figure 5: NeuroCom SMART Balance Master system. 
This system may be used to test balance and 
sensorimotor integration and control. 
 
Assessments, Surveys and Feedback: 
We may use a short battery of physical tests to assess each patient’s mobility capabilities. The 
Amputee Mobility Predictor [24] is a short group of tests that give a score suitable for estimating 
the “K‐Level” of persons with amputation. The same tests will be used in orthosis users to gauge 
their capacity. These tests will not be performed by healthy controls. 

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We use standard questionnaires to rate each patient’s perceived mobility and quality of life. 
Surveys will be administered at the beginning of the study to gauge each subject’s mobility 
outside the lab as well as at points during the study to gauge the impact of study interventions 
on mobility. For subjects with Multiple Sclerosis, questionnaires will be administered for the 
additional purpose of assessing the impact of impairments such as fatigue on their mobility 
before and during the study, and to collect information on their self‐rated disease severity. The 
specific surveys planned are the Prosthetic Limb Users Survey of Mobility (PLUS‐M) [25], [26] and 
the Prosthetic Mobility Questionnaire [17]. Other surveys that may be considered include: MOS 
Short Form 36 [27]; an NIH PROMIS physical function instrument (e.g. short form 10, 11, 20) [28]; 
the Locomotor Capabilities Index (LCI‐5) [29]; the Prosthetic Profile of the Amputee (PPA) [30]; 
the Prosthetic Evaluation Questionnaire – Mobility Subsection (PEQ‐MS) [15]–[17]; Activities‐ 
Specific Balance Confidence scale (ABC) [31], [32]; Socket Comfort Score [33]; the Scale for 
Evaluation of Rehabilitation‐Participation (USER‐P) [34]–[36]; the Orthotics and Prosthetics 
Users' Survey (OPUS) [37]; the Wong‐Baker faces pain rating scale [38]; and/or the PAR‐PRO 
participation scale [39]. Some questionnaires have sections that are irrelevant to this study; these 
sections may be skipped when administering the questionnaires. For the MS group, additional 
questionnaires will include: the Modified Fatigue Impact Scale (MFIS) [40], [41], the 12‐Item 
Multiple Sclerosis Walking Scale(MSWS‐12) [42], [43], the self‐Expanded Disability Status Scale 
(self‐EDSS) [44], [45], and the Psychosocial Impact of Assistive Devices Scale (PIADS) [46]. 
Finally, we will use custom questionnaires to gauge the utility of the devices under test. For the 
MS group, custom questionnaires will also be utilized to rate their daily fluctuations in fatigue 
and to communicate which shoes they utilized for the day, which is necessary as this impacts 
data interpretation. These questionnaires will be administered either on paper or on a computer 
by web form (e.g. using REDCap, Qualtrics™ or other tools compliant with HIPAA requirements). 
The subject code, but no other identifying information, will be collected on the form. Questions 
will be specific to each device or group of devices tested, because each is designed based on a 
different concept. Each questionnaire will be submitted for IRB review and approval prior to use 
with subjects. 
Questions may include ratings (e.g. 0‐10 ratings, visual analog scales, etc.) or rankings (e.g., 
best to worst, 1 to 5, etc.) of comfort, discomfort, utility, preference, pain, performance, fatigue, 
and specific features of the device’s perceived biomechanical behavior. For example, we may ask 
subjects to “rate the quality of forefoot rollover movement with this prosthesis,” or to “rate the 
severity of the mid‐stance ‘flat spot’ you perceive with this orthosis,” or “rate how comfortable 
would you feel relying on this device to walk along a forest trail.” We will also include an optional 
space for open comments, because user comments provide deep insight into how these kinds of 
devices can be improved. The surveys will exclude sensitive questions, including but not limited 
to: embarrassing, damaging, personal or invasive information; information that could potentially 

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identify the respondent; protected health information; detailed information about any health 
condition or disability. 
 
Outcome Measures 
Outcomes will generally be compared using a repeated‐measures design, in which each subject 
acts as his/her own control. This design is chosen to minimize the statistical problems caused by 
heterogeneity in the subject population. 
• Ground Reaction Force (GRF): force applied by the body to the ground. Peak forces and 
shape of the force vs. time trajectory are commonly used to assess gait quality. Forces 
closer to “normal” are usually considered better, but this goal may not apply in persons 
with amputation. 
• Center of Pressure (COP): location where the resultant GRF acts under the foot. Location 
of the COP relative to the foot or shank can characterize foot/ankle function. COP 
fluctuations are used to characterize standing balance. Hypotheses and intended effects 
on COP vary depending on the goal of a prosthesis’ design. 
• Joint Kinematics (ankle, knee and hip): plots of joint angle or its derivatives vs. time, and 
characterization of peak angles, range of motion, and variability. Kinematics closer to 
“normal” are usually considered better, but this goal may not apply in persons with 
amputation. 
• Joint Moments: plots of joint moment (torque) vs time or angle, and characterization of 
peak moments, variability, joint quasi‐stiffness, and other measures. Moments closer to 
“normal” are usually considered better, but this goal may not apply in persons with 
amputation. 
• Joint Powers: plots of joint power output vs. time, and characterization of peak power 
and total work. Power and work closer to “normal” are usually considered better, but this 
goal may not apply in persons with amputation. 
• Prosthesis Energy Storage and Return: Power flow into and out of a prosthesis. More is 
usually considered better, but nuances of mechanics can alter this goal. 
• Center of Mass (COM) Mechanics: work performed by each leg on the body COM, and 
COM velocity fluctuations in time. Typical measurable outcomes include total quantity 
and asymmetry in these measures. 
• Dynamic Mean Ankle Moment Arm (DMAMA): similar to a weighted average center‐of‐ 
pressure, recently developed to characterize gross kinematic ankle control. 
• Metabolic  Energy  Consumption:  Measured  through  indirect  calorimetry  (oxygen 

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consumption, optionally carbon dioxide production), energy consumption is used to 
assess overall effort or physiological load in a task. Reductions in energy consumption 
using one device vs. another are a common goal, though exercise‐related projects may be 
designed to cause the opposite. 
• Muscle Activity: Measured through electromyography. Outcomes include the plot of EMG 
magnitude vs time, relative timing of peak activation with respect to movements, and 
integrated EMG to assess a muscle’s overall load or stress. 
• Balance Assessments: scores and ratings from any or all of the NeuroCom Balance Master 
system’s standard tests (details [47]: PDF – webpage): 
o Sensory Organization Test (SOT): center of pressure fluctuations across multiple 
perturbations to test somatosensory, visual, and vestibular components of 
balance control. 
o Adaptation Test (ADT): center of pressure fluctuations when the standing surface 
is tilted. 
o Limits of Stability (LOS): maximal ability to lean in different directions. 
o Rhythmic Weight Shift (RWS): accuracy in controlling rhythmic leaning in different 
directions. 
o Weight Bearing Squat (WBS): asymmetry in weight support when standing and 
when squatting to 30, 60 and 90‐degree knee angles. 
o Unilateral Stance (US): center of pressure fluctuations during standing on one leg 
• Repeated movement paths from long‐term monitoring: location as reconstructed from 
GPS and wearable sensor data. Paths are used to determine where and when to assess 
gait parameters and segment kinematics. 
• Gait parameters and segment kinematics from long‐term monitoring: movements of the 
body segments on which wearable sensors are worn. Example outcomes include speed, 
stride length, stride width, foot clearance, cadence, gait asymmetry, joint angles, and 
others. 
• Survey Instrument scores: Prosthetic Limb Users Survey of Mobility (PLUS‐M) [25], [26] 
and the Prosthetic Mobility Questionnaire [17]. Also optionally the MOS Short Form 36 
[27]; an NIH PROMIS mobility instrument (e.g. short form 10, 11, 20) [28]; the Locomotor 
Capabilities Index (LCI‐5) [29]; the Prosthetic Profile of the Amputee (PPA) [30]; the 
Prosthetic Evaluation Questionnaire – Mobility Subsection (PEQ‐MS) [15]–[17]; Activities‐ 
Specific Balance Confidence scale (ABC) [31], [32]; the Socket Comfort Score [33]; the PAR‐ 
PRO [39], the Orthotics and Prosthetics Users' Survey (OPUS) [37]; the Wong‐Baker faces 

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pain rating scale [38]; and/or the Utrecht Scale for Evaluation of Rehabilitation‐ 
Participation (USER‐P) [34]–[36]. Scores on all of these instruments include better and 
worse directions. 
• Custom Surveys: Custom surveys may be used, including questions adapted from the 
standard survey instruments, as well as questions related to specific features or behaviors 
of the devices under test. 
• Measures of Gait and Balance Function for the Multiple Sclerosis subject subgroup: The 
Functional Gait Assessment [48] and 6 minute walk tests [49], [50] may be used to 
characterize MS‐specific impairments and differences in balance, gait, and measure of 
fatigue observed between study interventions. 
Specific Procedures – Comparing Prostheses and Orthoses using Real‐World Data 
Study Design: 
Subjects will wear one or more movement sensors on various body segments, especially the 
foot, as well as means of logging location data (e.g. a GPS, Bluetooth, Wifi receiver and/or cell 
phone app). Subjects will wear (movement sensors) and/or carry (phone) these sensors during 
extended measurement periods of up to three weeks per experimental condition, for up to four 
conditions (prostheses, orthoses or footwear). We will combine movement and location data to 
identify the most‐frequently‐repeated paths a person takes, and finally analyze movement along 
these paths to identify changes in mobility performance (Figure 6). We will also perform standard 
biomechanical analyses of posture and movement in the laboratory. 
NOTE: Because part of this study is the development of these methods, we may change the 
number of sensors, which sensors are used, how they are worn/carried, how long the take‐home 
tests are, the devices under study, and other details of the study, within the limits approved in 
the Study Procedures – General section of this protocol. 

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Figure 6: Example self‐test by the experimenters showing highly repeated straight walking 
trajectories found from a 10‐day walking test. The experimenter wore athletic shoes and 
sandals for 5 days each, indicated by solid lines and dashed lines respectively. The same color 
indicates same paths. Blue and red lines are walking trajectories in the hallway between the 
subject’s office and the restroom and water fountain (different directions are separated into 
two different paths). Yellow lines represent the sidewalk between the building where the 
subject works and a nearby bus stop. Purple lines represent a sidewalk between the same 
building and a dining location. 
 
Test Conditions: 
• Prosthetics branch 1: Participants with amputation will use 2‐4 prosthetic feet from 
different categories, each fit to their standard socket by a professional prosthetist. 
o Participants will use each prosthesis for a take‐home test of 1‐3 weeks of everyday 
life. Comparisons will include energy‐storage‐and‐return prostheses (ESR) vs. 
prostheses with a passive hydraulic ankle (PHA) vs. prostheses with a 
microprocessor ankle (MPA) (Figure 1). Comparisons may also include Articulated 
ESR (AESR) prostheses, which have one or more additional joints in the 
mechanism, or other types of standard commercial prostheses. 
o Before and after each take‐home period, participants will come to the lab for 
biomechanical testing and questionnaires and to be fitted with a new prosthetic 
foot to use for the next period. 
o The sensor systems will be worn on the affected and/or unaffected leg and foot 

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and/or the waist using a dedicated strap, and/or carried in a pocket or case (e.g. 
for data recorded by a cell phone application) throughout the study duration. 
• Prosthetics branch 2: participants with amputation will use 2 or more prosthetic feet that 
they already own and use regularly, with only Instrumentation (sensors) added by the 
study team. 
o Participants will use each prosthesis for a take‐home test of 1‐3 weeks of everyday 
life. Comparisons will include a daily‐use prosthesis, a running‐specific prosthesis, 
and any other prostheses a person uses on a regular basis. 
o The sensor systems will be worn on the affected and/or unaffected leg and foot 
and/or the waist using a dedicated strap, and/or carried in a pocket or case (e.g. 
for data recorded by a cell phone application) throughout the study duration. 
o Sensors will be installed either in the lab or at an off‐site location where a team 
member meets the subject. In such “off‐site installation” situations, a designated 
member of the study team will meet with the participant in a public space 
(possibly, but not limited to, their clinician’s office) to carry out the installation 
and validation of the take‐home wearable sensors. The participants will then 
proceed with the take‐home testing. 
o Only one lab or off‐site installation visit is required to set up the wearable sensors. 
Sensors will be removed by the subject and returned through the mail, or 
alternatively the subject may come to the lab for the team to remove them. 
• Orthotics branch: Participants with drop‐foot will have a standard orthosis fitted by a 
certified orthotist, as well as the Bioness L300 Go FES neuro‐orthosis. Other procedures 
are as above. 
• Participants with no mobility impairment may use different kinds of footwear, including 
shoes, sandals, boots, and/or different insoles. Other procedures are as above. 
• All subjects may participate in laboratory walking trials (treadmill or over‐ground) to 
measure the detailed biomechanical effects of the different devices. 
 
Instrumentation: 
• Instrumentation may include any or all of the measurements listed in the Study 
Procedures – General section. 
• Most likely measurements include: miniature inertial sensors, GPS, Bluetooth and Wifi 
location from a wearable receiver or cell phone app, force plate/force treadmill, EMG, 
motion capture, indirect calorimetry, and voice/photo/video recording. 

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Intended Outcome ‐ Primary: 
The primary outcome is the measured difference in stride length at identical walking speed 
when using different prostheses, orthoses, or footwear. We expect to observe increased stride 
length when using more compliant prostheses or the FES neuro‐orthosis. 
Intended Outcomes ‐ Secondary: 
The secondary outcomes include other measures of gait performance determined from the 
same system. Stride width, stride clearance, speed, stride frequency, ground reaction forces, 
and measures of gait regularity are among many analyses that will be performed with the data 
from this experiment. 
 
 
Data and Safety Monitoring Plan 
The PI will oversee compliance with the data and safety monitoring plan to ensure adherence 
to IRB guidelines. All researchers and research staff involved in the study are required to maintain 
Human Subjects and HIPAA training and will be continuously involved in data and safety 
monitoring. Data and safety monitoring will occur on a continuous basis. 
Adverse events or problems will be reviewed by the principal investigator as they occur and 
reported to the IRB in accordance with posted guidelines at the “Events Requiring Reporting to 
the IRB” page: https://kb.wisc.edu/hsirbs/18324. 
 
Data Processing/Data Analysis: 
Electromyographic, kinematic, kinetic, and metabolic data will be compared with different 
lower limb prostheses, orthoses and footwear, using repeated measures ANOVAs. In initial 
experiments measuring movement performance with only the subject’s own devices, we will 
use repeated measures ANOVAs to compare performance variables (e.g. EMG amplitude, gait 
economy, joint range of motion, peak ground reaction force) under different conditions (e.g. 
locomotion speed, incline, motor task). Corrections for multiple comparisons will be made using 
False Discovery Rate adjustments [51], [52]. In analysis of experimental conditions, we will use 
the new methods developed in this research for analyzing the same types of movement 
information, isolated to frequently‐repeated paths in everyday life. We may also analyze 
specific events of interest such as slips, trips or falls that occur in everyday life and are recorded 
by the wearable sensors [53]. 
 
Sample size 
For specific tests with a goal of publication, the sample size will be 10 participants. Studies with 
between 6 and 12 participants are common in the field, and have proven sufficient to 

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demonstrate many effects in a variety of studies of gait mechanics in persons using prostheses 
and orthoses [19], [54]–[61]. We estimate sample size from data on changes in gait mechanics 
across conditions with a past novel prosthesis [54], [56]. 
The sample size required per group is computed using the following formula: 
N (per group) = 2* ( (z(1‐α/2) + z(β))*σ/d )^2, 
where d is the expected difference in outcome value, post‐ vs. pre‐training; σ is the estimated 
standard deviation; α is the alpha error we would like to control; and β is the statistical power. 
Here we set a statistical goal of 80% power (β =0.80, z(β)=0.84) and α level 0.05 (z(1‐ α /2) = 1.96). 
Based on changes gait mechanics with a past novel prosthesis, we expect: a difference in ankle 
push‐off of 3.1 +/‐ 1.5 J across several conditions [54], or a difference in opposite‐leg collision 
work of 0.055 +/‐ 0.04 J/kg [56]. These give sample size estimates of 4, and 9 subjects, 
respectively. This sample‐size estimate is conservative, as it uses a two‐tailed test when in fact 
we expect to test for specific changes (one‐tailed test), and it does not account for repeated‐ 
measures structure in our experimental design. Therefore we expect 6‐10 subjects to provide 
sufficient statistical power. We plan to use 10 subjects for the tests of prostheses and orthoses 
at UW Madison. 
Analysis of Remotely‐Collected Data 
Data from UW‐Madison studies, and separately from WRNMMC studies, will be analyzed at 
both sites, but primarily UW‐Madison. Data from in‐lab biomechanics studies as well as take‐ 
home studies with wearable sensors will be transmitted between sites. Personnel at both sites 
may be involved in analyzing the biomechanical data (movement patterns, joint loads, etc.) and 
interpreting the location‐based data (e.g. speed, stride length, limb load) recorded from everyday 
life. Data transmission will use HIPAA‐compliant Box folders, HIPAA‐compliant folders on UW’s 
Campus Computing Initiative (CCI) systems, or other HIPAA‐compliant means approved by the 
DOD. Only coded data will be transmitted; each site will retain the only copy of its respective 
code key linking subject numbers to their direct identifiers, and the other site will not receive this 
information. 
 
Potential Risks 
Gait Analysis 
Gait analysis uses a motion capture system and force plates to estimate the forces on the 
muscles and skeleton during a motion under study. Motion capture uses reflective markers that 
are taped or glued to the skin. Tape or glue from the reflective markers could cause skin irritation. 
All attempts will be made to minimize the likelihood of irritation as any irritation would influence 
their gait abnormally and could not be sustained for long durations. Force plates may include in‐ 
ground and treadmill‐integrated versions. Risks associated with gait analysis include the 

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possibility of falling, or of experiencing muscle strain due to exertion. We will warn subjects that 
minor discomfort can be normal and that they should contact us if they are experiencing unusual 
muscle soreness. There is additional risk of fatigue from participation in locomotion trials. These 
risks are similar to everyday locomotion, but subjects will be given ample time to accommodate 
to different conditions before formal testing. 
Falls 
Walking and running inherently carry some risk of falls. These risks are similar in this study to 
those encountered in everyday activities. There is some elevated risk due to the effects of 
different devices and instrumentation on device fit and function. 
Device Fit 
For tests with prostheses and orthoses, there is a risk of skin irritation or abrasion due to 
contact between the device and the limb. The fit of any devices used will be checked repeatedly 
throughout the experimental sessions. Subjects using prostheses will wear their daily‐use 
prosthetic socket, or a custom version built by a certified prosthetist, in order to ensure proper 
fit. For take‐home tests, there is a slight increase in risk of skin irritation due to the change of 
equipment; subjects are asked to watch for signs of such problems and contact the research team 
if they occur. 
For some tests (for example, EMG or respiratory gas exchange measurements), the equipment 
itself may be uncomfortable. This equipment will be attached to the body and adjusted as 
comfortably as possible, and attention will be paid to subject‐specific adjustments to prevent 
unnecessary strain or load on the body. 
Device Function 
Subjects may experience minor discomfort with adjusting to the different lower‐limb 
prostheses and orthoses. This experience often passes quickly, but subjects will be instructed to 
inform experimenters and stop the experiment if the discomfort is too great or too persistent. 
There is a risk of malfunction whenever a device is used. With lower‐limb ambulatory aids 
(prostheses, orthoses), malfunction could result in a fall and/or muscle strain. 
Electromyography (EMG) 
EMG is a tool that measures muscle activity, an important component of movement control. It 
uses surface electrodes to measure the electrical signals produced by muscle contractions. Risks 
associated with this procedure are minor and may include soreness in the areas being tested. 
This may last for a few days and can be relieved with an over‐the‐counter pain reliever. 
Additionally, hair at the site of each EMG electrode may need to be shaved to achieve proper 
electrode adhesion and conductance. 
Disease Transmission: 
Because the same test devices, EMG equipment, pressure insoles, and respiratory gas exchange 

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equipment will be used by multiple subjects, there is potential for disease transmission. This risk 
is reduced to an extremely small level by two mechanisms. First, subjects under treatment for 
infectious disease will not be allowed to participate. Second, equipment surfaces with which 
subjects come in contact will be disinfected following each subject’s use of the equipment. The 
manufacturers of the test equipment items provide cleaning procedures, which will be 
performed between subjects. For the EMG system, this includes disinfecting the electrodes. For 
the respiratory gas exchange system, it involved disinfecting the mouthpiece and flow meter. The 
experimental devices (prostheses, orthoses) will be washed and/or disinfected with a sterilizing 
solution, wipe or spray. For pressure insoles and footwear, this is a shoe disinfectant and/or 
sanitizing wipe. Clothing will be washed between uses. Subject‐specific components such as the 
mounting straps for the FES neuro‐orthoses will be purchased new for each participant. 
Risk of Being Identified: 
For any tests performed outside the laboratory, the subject will be in public spaces. It is possible 
that someone may identify the subject during study participation. This risk is elevated compared 
to everyday life, as any novel devices or instrumentation will be more visible than standard 
prostheses or orthoses. 
The risk of being identified is elevated for participants whose sensors are installed off‐site in a 
public place. Because this involves more activity including handling multiple devices and 
conversing about the study, there is more occasion for the use of devices and sensors to be 
noticed by others. This risk will be highlighted and explicitly acknowledged by the participants in 
the Informed Consent process. 
Risk to Privacy: 
In take‐home studies, location tracking and reconstruction is a critical piece of the scientific 
approach to analyzing frequently‐repeated everyday movements. This location data can 
potentially expose private information such as the location of home, work and other places the 
participant travels to. Therefore, unaltered location data will not be published as a component 
of a public data set. Any figures or data published will have location withheld or obfuscated (such 
as offsetting location by a random large distance). We will remove place names, street names 
and building names from figures published with subjects’ location data. 
One of the possible means of recording location data is through use of a cell phone app that 
logs data. If this approach is used, it may include an additional risk to privacy because many such 
apps require installation on the user’s real account (e.g. Google Play or Apple Store), and 
additional registration with the app vendor according to the vendor’s terms of use. We will inform 
users of this risk on the Consent form and will mitigate it as outlined below in the Minimizing 
Risks section. 
Another risk to privacy is from audio recordings in voice recordings made during everyday life. 
Recordings will only be made when initiated by the participant. Users will be instructed to report 

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only balance‐ and mobility‐related events using voice recordings. Precautions will be taken to 
ensure that the privacy of non‐participants is respected, including transcription by a member of 
the study team who will transcribe only conversation related to the study. 
Another risk to privacy is from identifiable photos/videos recorded during the procedures. 
Explicit permission will be sought on the Informed Consent form before identifiable images are 
recorded. 
Minimizing Risks 
Subjects will be supervised at all times during the lab and field testing and will easily be able to 
communicate any discomfort or fatigue. Subjects will be able to take breaks whenever necessary, 
and may discontinue participation at any time. Subjects will be supplied with water to drink as 
needed. If a treadmill is used, handrails or an overhead harness will be used to prevent falls, and 
emergency stop buttons will also be within reach of the subject. During balance testing on the 
NeuroCom Balance Master system, an overhead harness will be used. During field testing, the 
subject’s prescribed prosthesis, orthosis, or footwear, as well as any necessary tools, will be 
brought along by the attending experimenter, in case the need to change or remove an 
experimental device arises. 
For take‐home testing of devices, only commercially available or standard‐of‐care devices will 
be used. Subjects will be required to self‐supervise, but will be given cell phone contact 
information for two or more members of the study team, for contact in case any difficulty arises. 
Subjects will be advised to keep their prescribed prosthesis and tools available, and to check 
regularly for discomfort or skin breakdown. A member of the study team will make weekly calls 
to the participants to inquire whether there are any problems with the devices, or any adverse 
effects. 
The "take‐home" portion of the study could be affected by a pregnancy that arises after initial 
enrollment. Because the take‐home portion only uses standard commercially available devices, 
the risk in this case is comparable to that of ordinary life. Nevertheless, participants will be asked 
if they are pregnant during each weekly call, and if so they will be asked about the estimated 
gestation time. Subjects will be allowed to continue or discontinue participation according to 
their own discretion within the first 12 weeks of pregnancy. After 12 weeks of pregnancy, 
participation will be discontinued. 
Risk of the failure in the prostheses and orthoses will be minimized through use of devices 
approved for patient use. Precautions will be taken to ensure safety even if the device does fail 
(malfunction or break), including the following: 
• During all testing, subjects will be instructed to pay attention to the feel and sound of 
the devices and report any changes. Experimenters will also attend to device sounds 
and appearance. Most failures are preceded by warning signs and can be prevented 

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with user attention. 
• During testing on a treadmill, handrails and an emergency stop button will be available 
within easy reach of the subject, unless an overhead harness is used. 
• During over‐ground laboratory or field testing, an experimenter will follow the test 
subject, bringing a replacement prosthesis and tools in case the prosthesis needs to be 
changed. 
• During running trials over‐ground, the subjects will wear a helmet and knee/elbow 
pads. 
• During running trials on the treadmill, handrails or an overhead harness will be used to 
prevent injurious falls. 
Discomfort due to energy expenditure measurement equipment will be minimized by proper 
adjustment of the device to fit both the face and the torso (wearable components). 
Skin irritation due to motion capture markers and muscle activity electrodes will be minimized 
by careful placement to avoid tugging or twisting the skin. Subjects will be instructed to report 
any discomfort, and the test will be discontinued if there is unresolvable serious discomfort. 
Physical and psychological stress due to the physical task demands will be minimized by 
providing appropriate rest periods between sequential trials (ca. 5 minutes). Fatigue in lab testing 
will be managed by ensuring no more than 6 minutes of continuous locomotion and no more 
than 5 hours spent in the lab in a single day. Fatigue in field testing will be managed by 
accompanying the subject throughout testing. In both settings, the experimenter will regularly 
inquire whether the subject needs rest. Fatigue in take‐home testing is expected to be similar to 
everyday life. 
Psychological stress due to perceived performance demands will be minimized by explaining 
the protocol in terms of doing “what you can do comfortably” (not “the best you can”), and by 
reiterating that the subject can stop at any time without consequence. 
Audio recordings of the subject’s voice could contain private information. The following 
precautions will be taken to ensure appropriate privacy protections while also ensuring the 
necessary data are obtained: 
• 
Voice recordings will be made on a cell phone application only when recording is 
activated by the participant. Files will be transferred by the participant to the study 
team using a USB cable upon return to the laboratory, and will be stored with the 
other data files. Participants will be free to delete recordings following this transfer, 
but will not be required to because the files record the subjects’ own voices and 
events. 

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• 
Voice files will be transcribed by a member of the study team, recording only 
information related to the event in question (editing out background and unrelated 
conversation). 
• 
Voice files will not be accessible to persons outside the study team, and only 
transcripts will be used for public dissemination (papers, presentations). 
Identifiable photos and videos will only be recorded if consent to record and show identifiable 
images is given by the subjects. Non‐identifiable images may be recorded for analysis and for 
documentation and verification of the experimental procedures even if subjects decline to give 
permission for identifiable images. 
Risk of identification in public spaces cannot be mitigated, but subjects will be informed of this 
risk and can withdraw if it is unacceptable. The elevated risk of identification for those in the off‐ 
site installation procedure will be included as a dedicated item in the Consent form. 
Unaltered location data (a privacy risk) will not be published as a component of a public data 
set. Any figures or data published will have location withheld or obfuscated (such as offsetting 
location by a random large distance). We will remove place names, street names and building 
names from any figures published with location data. 
Risks to privacy derived from the need to install a cell phone app will be minimized using several 
different techniques, to be chosen as the sensor system is finalized. First, our preferred method 
is to not use a cell phone at all, but rather the fully‐embedded system we are designing. If we do 
need an app, our preferred approach is to install a custom app that is not on the Google Play 
store or the Apple Store. We have developed one such app in pilot testing, and installed it directly 
on an iOS device (but it has limitations, and we do not yet have one for Android). If instead we 
choose a publicly available app (due to convenience, improved features like data transmission 
capability, etc.), then the need to install it on the user’s own Google or Apple account cannot be 
avoided. In this case, we will attempt to minimize exposure of personal data to the app vendor 
by creating an account with lab credentials such as a lab email address (e.g. 
“wearableSubject14@g‐groups.wisc.edu”, which will forward to a study team member instead 
of the subject). If none of these is practical or satisfactory to the subject, then the subject will be 
given the opportunity to refuse participation if he/she objects to installing and creating his/her 
own account. 
 
Medical emergencies 
Medical emergencies will be handled through standard emergency services (i.e., calling 9‐1‐1). 
Oversight will be provided by the PI or other Study Personnel in attendance during testing. 
Specific oversight of subjects who use prostheses or orthoses will be provided by the Certified 
Prosthetist or Orthotist, as related to limitations on activity and fitting of experimental devices 

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to avoid irritation or fall risk. Medical emergencies during take‐home portions of the experiment 
will be handled by the participants without intervention by the study team. Subjects will be asked 
to report any emergency events to the Study Team for evaluation of whether the study 
contributed to the emergency. 
 
Benefits 
In the prosthetics study, subjects may receive temporary benefits from involvement in the 
study, if they find the test devices preferable to their prescribed devices. Such experiences could 
also provide information to help them improve their future care. No other benefits are expected 
for subjects involved in the prosthetics study. In the orthotics study, subjects benefit from the 
unusual circumstance of access to extended trial periods of two different foot‐drop orthoses 
which may aid their decision making over which device to pursue. No other benefits are expected 
for subjects involved in the orthotics study. 
There are significant potential scientific benefits in the prescription of proper prosthetic and 
orthotic technologies in patient care. Results from this study will provide documentation of 
motor behavior across a wide range of motor tasks in patients and unaffected subjects. 
The proposed research will benefit society through: 
• improving our understanding of how the different prostheses and orthotic 
interventions affect walking and running. 
• improving clinical care by improving methods to assess mobility outcomes during real‐ 
world, everyday life 
 
Data and Record Keeping 
The PI will oversee the management of the study dataset. Data Confidentiality will be ensured 
by allowing only individuals involved with the study to have access to PHI, all identifying 
information, and all collected datasets, which will be stored in locked cabinets in the PI’s 
Laboratory, on password protected computer systems, or on HIPAA compliant servers. Coding 
and de‐identification of datasets have been described under the privacy and confidentiality 
section. Data collection methods have been described in detail in the study procedures section. 
Identifiable study records will be kept for five years after study completion at UW‐Madison and 
de‐identified data will be banked indefinitely. 
Coded data with no direct identifiers will be transmitted using HIPAA‐compliant means 
between the primary site at UW and collaborating scientists at WRNMMC. This data transmission 
is necessary to allow the collaborators to best analyze and interpret the data. Each site will retain 
the only copy of the code key for data collected at that site. Details of the data transmission have 

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been described in the Data Processing/Data Analysis section and the Privacy and Confidentiality 
section. 
Following government policy, de‐identified data may be posted on publicly accessible 
repositories for future analysis related to new scientific questions that can be informed by the 
tests performed in this research. The existing code linking data to individual subjects will be 
removed from any such copy of the data set, and a new code with no link will be added instead. 
These de‐identified data are no longer “human subject data” and hence are suitable for public 
release. 
Five years after study completion, data will be permanently de‐identified. The consent forms 
and Health Questionnaires containing the link between codes and personal identifiers will be 
destroyed. These de‐identified data are no longer “human subjects data” and hence will be kept 
indefinitely for future research use, such as re‐analysis to address new hypotheses. 

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