Villency - Proof of Action: Foot Device, Balance and Sway, Kinematics of Walking
Phase: NA
Conditions: Balance
Sponsor: University of Florida

Official Title: Villency ‐ Proof of Action: Foot Device, Balance and Sway, Kinematics of Walking 
NCT: NCT03663816 
Document Date: October 5, 2018 

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Title 
 
Villency-Proof of Action:  Foot Device, Balance and Sway, Kinematics of Walking   
 
Investigators: 
 
Heather Vincent, PhD  
 
 
Division of Research, Department of Orthopaedics  
and Rehabilitation, College of Medicine 
MaryBeth Horodyski, EdD, LAT, ATC  
Division of Research, Department of Orthopaedics  
and Rehabilitation, College of Medicine 
Cong Chen, MS  
Division of Research, Department of Orthopaedics 
and Rehabilitation, College of Medicine 
Sharareh Sharififar, PhD  
Division of Research, Department of Orthopaedics 
and Rehabilitation, College of Medicine 
Daniel Bailey, BS 
Division of Research, Department of Orthopaedics 
and Rehabilitation, College of Medicine 
Michelle Bruner, MS, LAT, ATC 
Division of Research, Department of Orthopaedics 
and Rehabilitation, College of Medicine 
Chris Koenig, MS, LAT, ATC 
Division of Research, Department of Orthopaedics 
and Rehabilitation, College of Medicine 
 
Abstract 
 
Background: Limited evidence is available on experimental foot devices that are designed to 
improve functional features of balance, postural sway and walking gait via cutaneous stimulation 
to the plantar surface. There are numerous studies of shoe insert effects on motion features of 
the foot and gait, but these inserts are primarily to manage clinical conditions or injury. We 
propose that appropriately-designed, stimulatory - but not mechanically supportive - devices 
could enhance control of balance, postural sway and key features of walking gait in healthy 
people. This has yet to be tested. 
Purpose: There are two purposes to this proof of action study: 1). Determine the effect of an 
experimental foot device on static balance and center of mass displacement (sway) during 
standing; and 2). Determine the effect of an experimental foot device on walking gait 
temporalspatial parameters, ground reaction force patterns and joint forces, and relative foot 
pressure patterns.  
Methods: A proof of action repeated-measures study will be conducted in which healthy men 
and women (N=15) will be recruited to perform a series of balance and gait measures before 
using the foot device for a week and after the week of use. The following functional tasks will be 
performed at each time point: static balance on force plates (two-legged stance, one-legged 
stance and tandem stance), walking gait measures on an instrumented treadmill (at a preferred 
speed and a standardized speed) and walking measures on a pressure-sensor filled gait mat. 
For balance, the center of mass displacement, the variation about the displacement and the 
speed of the displacement will be calculated during post-processing. For gait, the ankle, knee 
and hip joint moments and joint excursion kinematics in the sagittal plane of motion will be 
calculated. The peak ground reaction force, the rate of impact loading and the impulses will be 
calculated during post-processing. A repeated measures analysis of variance will be used to 
determine whether significant improvements in the functional outcomes occurred. The one-week 
change scores in the functional task outcomes will be calculated, and effect sizes of the foot 
IRB Approved at the 
Protocol Level 
Oct 05, 2018
20182379

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device on the key functional variables will be determined using Cohen’s d. Significance will be 
established at p<0.05. 
Application: The findings from this study will improve our understanding of foot device impact 
on functional performance in people without pre-existing conditions, and will help us create 
effect sizes for subsequent larger trials. 
Introduction 
 
The human foot is the initial point of contact between the body and the environment, and 
is a critical point to provide sensory information to the central nervous system during dynamic 
and static tasks (Nurse et al. 2005). The specialized mechanoreceptors of the plantar surface of 
the foot influence balance, dynamic stability and motion correction strategies. Thus, cutaneous 
stimulation of the nerves in the foot can dramatically change the motion of the lower extremity. 
For example, during walking and running, stimulation of the foot nerves (through varied 
experimental methods) can directly impact α-motorneuron output to the leg musculature (Nurse 
et al. 2005; Zehr et al. 1997). This output alters the kinematics of motion during gait. 
A common application of this concept is the use of in-shoe devices, such as orthotics, to 
change foot movement. Shoe devices are frequently used to treat lower extremity injury (Dixon 
and McNally 2008) and manage clinical conditions such as ankle instability, osteoarthritis or 
sacroiliac joint pain (Cho and Yoon 2015; Hamyln et al. 2012; McKeon et al. 2012; Rao et al. 
2009). Depending on the design, material and length, these devices have different effects on 
foot motion (Dixon and McNally 2008) and along the whole kinematic chain. Some evidence 
shows favorable improvements in postural stability with shoe insert orthotics over two weeks 
(Hamyln 2012) in individuals with ankle instability. Limited studies report immediate 
improvement in balance correction in response to fast, random postural perturbations with foot 
devices that facilitate sensation to the plantar surface (Maki et al. 1999). The increased plantar 
sensitivity does not appear to habituate over weeks, as shown by studies of older adults who 
can maintain their improved lateral stability over the long-term with the use of insoles (Perry et 
al. 2008).  
The underlying theory is that these collective devices may, in part, improve plantar 
proprioception and motion control in loaded conditions. However, the design of most shoe 
devices is meant to change foot motion and mitigate impact forces rather than allow the foot to 
enhance the proprioceptive ability. For example, orthotics may allow foot motion in the 
metatarsals, but constrict or “support” the arch (Dixon and McNally 2008). Others are rigid and 
long to minimize foot splay, and others are partial length along the plantar surface and contact 
the heel surface only. Orthotics are comprised of different materials ranging from gels, foams, 
plastic and combinations of these materials at different thicknesses and contour levels. Some 
devices are intended to cushion and reduce shock (Ramanathan et al. 2008). Moreover, the 
studies that report effects of such devices have generally enrolled individuals with preexisting 
orthopedic conditions and are more likely to find effects on functional outcomes. The limited 
data from experimental foot devices or methods that increase plantar sensitivity show promise 
(Maki et al. 1999; Perry et al. 2008). These experimental methods modify contact surface with 
the foot and use ridges, bumps or other textured surface to theoretically stimulate the cutaneous 
nerves. The participants reported increased awareness of the contact surface and increased 
responsiveness to positional perturbations.  
Deficits in the Literature. There are two major challenges in interpreting the available 
evidence on the actions of these foot devices on balance and gait kinetics and kinematics. First, 
we have very little evidence of the shoe device impact or mechanism in the general healthy 

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population. Second, when using a foot device for the purpose of improving proprioception, the 
device should be simple and stimulate (but not mechanically support) the plantar surface of the 
foot. This evidence is sparse. Presently, we do not currently know how the motion, ground 
reaction forces and joint moments of the lower extremity joints are impacted with a 
proprioceptive foot device among the general healthy population. 
We seek to expand the understanding and application of the foot device concept to 
healthy people for injury prevention and performance enhancement. We will determine whether 
a different design of foot device can improve static balance and gait parameters. Medicine 
trends are moving toward self-management of healthy movement and preventative strategies to 
injury. More evidence is needed to determine whether the type of foot device we will test here 
has potential to improve balance, posture and stability – all of which promote healthy movement 
and reduce injury risk over the long-term. Here, a proof of action study will be performed to 
determine the effect size of the foot device use on functional task outcomes of balance and gait 
in healthy people.  
 
Specific Aims 
The Specific Aims of this study are to determine the effect of a foot device after one week of 
acclimation and use on functional variables of balance and gait. We will test the following 
hypotheses using the following specific aims: 
1)  Determine the effect of an experimental foot device on static balance and center of 
mass displacement (sway) during standing. 
Hypothesis: Compared to the initial baseline measures, static balance will be improved as 
shown by reductions in the displacement of the center of mass, speed of motion of the 
center of mass and less trunk sway. We hypothesize that improvements in balance and 
sway will occur in two-legged stance, single-legged stance and in tandem stance.  
2)  Determine the effect of an experimental foot device on walking gait temporalspatial 
parameters, ground reaction force patterns and joint forces, and relative foot 
pressure patterns.  
Hypothesis 2a: After one week, participants will demonstrate improvements in temporal 
spatial parameters (gait speed, stride width, swing time and single support time) compared 
to initial baseline measures. We also hypothesize that the rate of impact loading will be 
lower after one week of use.  
Hypothesis 2b: We hypothesize that there will be a shift in foot pressure patterns from the 
typical pattern to that of pressures that indicate transfer of body weight over the heel, lateral 
metatarsals and hallux. 
Methods 
Study Design: This is a repeated-measures study in which participants will serve as their own 
control. Balance and gait measures will be collected during an initial visit and after one week of 
using the experimental foot device.  
 
Participants: Healthy men and women (N=15) will be enrolled into the study. Participants must 
match all the following criteria to be enrolled: 
 
Inclusion: 

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● Healthy men and women aged18 to 40 years 
● Willing to maintain current level of physical activity during the study period of a week (no 
increase or decrease of activity level). 
 
Exclusion Criteria: 
● Moderate or severe obesity (body mass index >35kg/m2) 
● Known diagnosis of cardiovascular, orthopaedic, or neurological conditions, uncontrolled 
diabetes, or any condition that impacts normal walking ability  
● Any current ankle, knee, hip or low back pain  
● Currently using any knee or ankle brace on a regular basis for joint pains 
● Severe back pain, prior spinal fusion or spinal deformity that would affect gait 
● Major cardiac or pulmonary conditions and any orthopedic limitation  that precludes their 
ability to independently walk for 10 minutes or longer 
● Any major orthopedic injury within the prior 12 months 
 
Recruitment and Informed Consent: 
Participants will be recruited from the Gainesville area using flyers, online web ads and word of 
mouth. If interested, the potential participants will call or email the study team. The study 
coordinator will then explain the study in detail using the informed consent document as the 
basis of the discussion, and answer any questions from the participant. Participants can take 
the consent document to review the information carefully. If the individual does agree to pursue 
the study, written signatures on the informed consent will then be obtained. The participant will 
be given a copy of the informed consent document after it is signed and dated. Participants are 
free to withdraw from the study at any time. The protocol and consent documents identify the 
research team’s obligations to the participant and the participant's obligations to the study while 
he or she is a participant. 
 
Study Schedule:  
Participants will be involved in a total of two study visits: initial baseline and one week. This 
study will include a series of descriptive variables and potential covariates, and objective 
assessments that relate to the Study Aims.  Each visit will take place at the UF Orthopaedics 
and Sports Medicine Institute’s (OSMI) Human Dynamics Laboratories. Every participant will 
receive standard procedural and safety instructions about each test. With the exception of the 
participant history, covariates and height and weight, all of the following outcome measures will 
be taken at baseline and one week.  
 
Study Measurements: 
Participant History and Covariates: A study-specific brief health history questionnaire will be 
completed during the initial visit which includes age, weight, body mass index, current medical 
issues, current activity level and type of shoe regularly worn for exercise and daily use. All 
answers will be self-reported. 
 
Body weight and height: Height and weight will be collected using a standard, medical grade 
scale during the initial visit. 
 
Functional Tasks and Preparation: The use of the foot device may impact how individuals 
react with the ground, causing changes in balance and postural shifting, impact loading rates 
and peak force development and pressure patterns as weight is transferred over the feet. As 

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such, functional abilities including balance and comprehensive gait analysis will be performed. 
These tests will provide insight on how the foot device potentially impacts the control of balance, 
and the speed and quality of walking gait. To track movement of body segments during the 
subsequent testing, reflective markers will be applied to anatomical landmarks and body 
segments using the methods of Kadaba et al. (1990). These markers will be placed on 
important anatomical landmarks and body segments (For the static calibration trials, markers 
will be placed bilaterally on the acromion processes, triceps, lateral elbows, forearms, wrists, 
posterior superior iliac spine, anterior superior iliac spine, anterior thigh, medial and lateral 
condyles of the femur, tibial tuberosity, medial and lateral malleoli, calcaneus, lateral to the head 
of the fifth metatarsal, and medial to the base of the hallux. An offset marker will be placed on 
the right scapular inferior angle. For the walking trials, medial knee and ankle markers will be 
removed. Offset markers will be used to facilitate automatic marker tracking. After calibrating the 
system, a static pose will be used to create a model for subsequent analysis). The pelvis 
segment will be developed from the anterior and posterior superior iliac spine markers, and the 
anterior orientation will be expressed relative to the horizontal as 0° of anterior tilt. Joint angular 
displacements of the ankle, knee, hip and pelvis in sagittal plant of motion will be calculated 
using commercially-available software (Visual3D, C-Motion Inc,, Germantown, MD, USA). 
 
Balance and Postural Sway Conditions: Each participant will perform three conditions of 
balance on the in-ground force plates (AMTI, Watertown MA). This measure is one of the most 
important variables in the study and was used to generate the sample size estimate. The three 
conditions will include two-foot stance, single foot stance and tandem balance stance. Following 
standardized instructions, participants will hold each position for 20-second intervals during 
which time force data will be captured at 1200 Hz. These collective measures will take roughly 
two minutes. This measurement technique is commonly used to assess postural stability and 
balance (Brown et al 2007; McKeon et al. 2012; Menz et al. 2017) and has demonstrated 
sensitivity to detecting change with shoe inserts that were designed to improve balance and gait 
(Menz et al. 2017). The images below show the three balance conditions: 
 
 
 
 
 
 
A.                              B.                                  C.  
 
A. Two-foot stance: Participants will be asked to place their feet together and hold their arms at 
their sides. Participants will stand looking straight ahead and hold as still as possible. 
B. Single foot balance: Participants will be asked to stand on the dominant foot and hold the 
other foot up, such that the knee creates a 90 degree angle. The participants will stand looking 
straight ahead and hold as still as possible. 

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C. Tandem stance: Participants will be asked to place their dominant foot forward and place the 
toes of their other foot to the heel of the dominant foot. The participants will stand looking 
straight ahead and hold as still as possible.  
Once the data are collected, calculations of center of mass displacement (in cm), the variability 
of displacement and area (cm2), and the peak speed of displacement (cm per second) will be 
determined. These values will provide insight about direction of sway and how quickly sway 
occurs during these three balance conditions. 
 
Walking Gait. Two types of gait tests will be used to comprehensively characterize the gait 
patterns, motion and foot pressures that occur during walking: a force-plated treadmill and a 
GaitRite© gait mat. First, kinematic and kinetic measures will be captured using 3-dimensional 
(3D) motion capture techniques. High-speed filming will also be used to record a video 
reference of each condition (Edgertronic Inc, San Jose, CA; frame rate=498 frames per 
second).Once completed, each participant will walk across a gait mat to obtain relative foot 
pressure patterns. The total time to complete all the gait tests is approximately 15-20 minutes. 
 
3D Instrumented Motion Analysis on Force Plated Treadmill: To determine ground reaction 
forces (GRFs) during walking, dynamic assessments of these forces and force patterns 
(kinetics) will be collected during a 10 second sample period with 
participants walking a self-selected speed and a standardized 
speed on a force-plated treadmill (AMTI, Watertown, MA USA). 
Each participant will first be acclimated to the treadmill, then 
allowed to walk for three minutes at a self-selected pace. 
Participants’ walking motion (kinematics) will be captured by using a 
high-speed 7-camera optical motion analysis system (Motion 
Analysis Corp, Santa Rosa, CA, USA).  Then participants will be 
asked to walk at standardized speed of (3.2 mph), a speed at which 
corresponds to an average preferred walking speed of healthy 
adults in the age range we will use here (Van Uden and Besser, 
2004). 
Kinematics and kinetics will be derived from the marker data 
using standard rigid body mechanics equations implemented within commercially available 
software (Cole et al. 1993). During the last minute, a sample of walking data will be captured 
and written to disc for offline processing. The following measures will be obtained in the sagittal 
plane for the ankle, knee, hip and pelvis joint: joint angles at foot contact, peak angles at mid-
stance and excursion (range of motion per joint). These data will be processed using Visual 3D 
software. The peak GRFs in each of the three planes (sagittal, frontal and transverse) will be 
determined. Knee moments and the rate of force development after foot contact will be 
calculated for each leg (DeLeva et al. 1996). Moments will be adjusted for body weight X height. 
The picture above left shows the instrumented treadmill setup. The vertical displacement of the 
center of mass (COM) will be calculated as the difference in the maximal and minimal vertical 
height of the estimated COM during an average gait cycle. The stance time was determined as 
the percent of the gait cycle during which the foot made contact with the treadmill. Cadence, 
COM vertical displacement, step length, step width will also be calculated.  
 
GaitRite© Gait Mat Measures: Participants will be asked to walk across the 26’ long gait mat 
and their self-selected speed to capture the foot pressure patterns. The pressures are color 

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mapped, where higher pressures are brighter reds and blues, where areas of low pressure are 
represented by grey or light blue. Temporalspatial parameters will also be captured (cadence, 
speed, step lengths, step width, toe out angle, stance and swing time 
and variability about these measures). A total of six trials will be 
captured and averaged to determine the typical loading pressure 
pattern. The change in peak foot pressure location will be documented 
from a 12-square grid generated from the plantar surface on the mat. In 
each of the 12 squares, averaged pressures will be automatically 
calculated by the software. If the location of the peak pressure square 
on the grid changes from the initial baseline measure to week one shifts 
from an unfavorable location to the expected healthy locations (heel, 
lateral metarsals and hallus), this will be coded as positive change. The 
peak pressure values will also be captured and recorded at each time 
point. Walking gait mats such as these are widely used to track changes 
in gait with different interventions and are sensitive to changes in temporalspatial parameters 
and relative foot pressure patterns (Nandikolla et al. 2017). Previous research has established 
the test–retest reliability of temporospatial parameters derived from the GAITRite system, with 
reports of good to excellent reliability, both within and between-days, in healthy adults (Van 
Uden and Besser, 2004). The picture above left shows the GaitRite gait mat in use during a 
typical walking trial. 
 
Foot Device and Prescription for Use 
The foot device is similar to a shoe insert (see image below). The devices are pre-sized to fit a 
variety of shoe sizes for men and women. Participants will be instructed to wear the device in 
one pair of their own personal shoes for one hour each day for days one and two. On each 
subsequent day until day seven, the time for use will increase by one hour per day. This is 
nearly identical to wear progressions in other foot orthotic-shoe devices prescriptions (Hamlyn 
et al. 2012), and is expected to be well-tolerated and safe. These same shoes will be worn for 
the initial and final testing sessions in the lab to reduce biomechanical variability of measures, 
and to replicate what the use of the device would be like for the general population on a daily 
basis. Image A below shows the shape of the foam-based device and the surface area that will 
make contact with the foot, and Image B shows a close up of the textured rubberized material 
will be that will make contact with the foot. These inserts weigh approximately 1.5 ounces. 
A.                                         B. 
                            
  
 
 
 
 
 
 
 
 
 

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Statistics 
Sample size:  
Because there are no directly comparable data from which to construct a matched sample size 
estimate, we have used the study with the closest match in aims and population (Hamlyn et al. 
2012).  For the matched pairs design, this study would require a sample size of 14 people to 
achieve a power of 80% and a level of significance of 5% (two sided), for detecting a mean of 
the differences of 17 cm2 of postural sway area between pairs, assuming the standard deviation 
of the differences to be 20 cm2.  
Analysis for the Specific Aims: 
Descriptive statistics (means and standard deviations for continuous variables, frequencies and 
percents for categorical variables) will be calculated on all study variables and demographics. 
Normality of the data will first be confirmed using Shapiro-Wilk tests. 
 
Aim 1: Determine the effect of an experimental foot device on static balance and center 
of mass displacement (sway) during standing.  We will use repeated measures analysis of 
variance (ANOVA) to determine whether significant improvements in the functional outcomes 
occurred. The dependent variables will be the key functional task outcomes for balance (center 
of mass displacement, variability of displacement and area, and the peak speed of 
displacement) and the independent variable will be time (initial assessment, week one). 
Covariates to the models will be body weight and sex. The one-week change scores in the 
functional task outcomes will be calculated, and effect sizes of the foot device will be 
determined using Cohen’s d. For these described statistical tests an α level of 0.05 will be 
established as significant. 
 
 
Aim 2: Determine the effect of an experimental foot device on walking gait 
temporalspatial parameters, ground reaction force patterns and joint forces, and relative 
foot pressure patterns. Similar to Aim 1, repeated measures ANOVAs will be used to 
determine whether significant improvements in the dependent variables for walking gait 
occurred. The dependent variables will be the kinematics in sagittal plane, temporalspatial 
parameters, ground reaction forces, impact loading rate and foot pressure change. The 
independent variable will be time (initial assessment, week one). The one-week change scores 
in the functional task outcomes will be calculated, and effect sizes of the foot device will be 
determined using Cohen’s d. To determine whether any statistically significant shifts in the peak 
pressures on the plantar surface occurred, Chi Square (χ2) tests will be used. An α level of 0.05 
will be established as significant. 
Data Management: Data will be collected and saved in Microsoft Excel®. The electronic files 
will be de-identified and saved on the departmental, firewalled encrypted server. Data will be 
reviewed before analysis and cleaned to ensure that all numbers are within expected limits. 
Once data collection is complete, statistical analyses will be performed using the Statistical 
Package for the Social Sciences (SPSS version 24; IBM Chicago, IL).   
 
Possible Discomforts and Risks, Protections against Risks 
 
There are minor potential risks and discomforts associated with this study. All precautions will 
be put into place to minimize these risks. 
Foot Device and Study Measures. The risks to participating in this study are minimal.  A 
potential discomfort may be related to wearing the foot device during the one week period. The 
devices are purposefully designed to stimulate the plantar surface of the foot and may feel 

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slightly unstable. Adjusting to the slight instability might initially feel uncomfortable for some 
people when they first wear the foot device. This discomfort is expected to improve over time as 
the participant becomes comfortable wearing them each day. A second anticipated discomfort is 
the development of mild muscle soreness in the lower extremities from wearing the foot device. 
As occurs with the start of any new shoe or shoe device where muscles engage in 
unaccustomed activity, muscle soreness may develop. This may appear in the muscles of the 
feet, lower leg, upper leg or gluteal muscles. This soreness is transient and is expected to 
dissipate within 48-72 hours.  
With any treadmill or walking tests, there is the very small possibility of injury. We take 
all precautions to reduce this risk of falling or injury by familiarizing the participant with the 
treadmill, coaching them through all the processes of the treadmill use and having spotters next 
to the treadmill. 
Informed Consent. Written informed consent will be obtained after explanation to subjects 
about all procedures and time commitments. The study coordinator will explain to prospective 
participants the purpose, methods and extent of the study. Potential participants will be asked to 
read the informed consent form and to ask questions. The form will be written in simple, easy-
to-understand language. We require the coordinator to review all key aspects of the study 
verbally. They will then question potential participants to ascertain whether they have 
understood the information.  A copy of the signed and dated consent form will be given to 
participants, and the original document will be placed in subjects’ individual study files, which 
will be stored in a locked, secure location in the OSMI. 
 
Confidentiality. Data will be used only in aggregate and no identifying characteristics of 
individuals will be published or presented. Confidentiality of data will be maintained by using 
research identification numbers that uniquely identify each individual. Safeguards will be 
established to ensure the security and privacy of participants’ study records. Appropriate 
measures will be taken to prevent unauthorized use of study information. Data other than 
demographic information do not use names as an identifier. The research ID number will be 
used. The research records will be kept in a locked room in the OSMI. The files matching 
participants' names and demographic information with research ID numbers will be kept in a 
separate room and will be stored in a locked file that uses a different key from that of all other 
files. Only the study team members will have access to these files. After the study is completed, 
local data will be stored with other completed research studies in the OSMI records room. 
 
Data Safety and Monitoring Plan.  Although the risk for an untoward event occurring due to 
participation in the study is extremely low, we will put all data safety and monitoring procedures 
into place. A Data and Safety Monitoring Plan (DSMP) will be implemented to ensure the safety 
of all participants involved in the study and to ensure the validity and integrity of the data. The 
study team will monitor all aspects of safety. The Study Coordinator will meet monthly to review 
all Serious, Unexpected and On-site adverse events and will make recommendations to the PI 
and Co-investigators. Study safety personnel will be notified of all Serious and on-site events 
within 24 hrs of initial confirmation. The PI will complete an Event notification and Evaluation 
form which will be reviewed by the IRB. A summary of non-serious events will be reported to the 
PI and IRB.A structured safety monitoring system will be established in order to both assure 
real-time participant care and unbiased monitoring of adverse outcomes. For ongoing 
participant safety, events will be assessed by the PI, physician, and Co-investigators to 
determine if they are Serious, Unexpected or On-site, as defined below. If so, an event 
evaluation form will be completed that will include a description of the event, a classification of 
seriousness, assessment of potential relationship to the study, assessment of need for change 
in the consent or the study activities, a summary of known prior health issues, event outcome 

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and a classification of the main organ system involved. The classification of potential 
relationship to the intervention is as follows: 
 
Definite  
 
Temporal pattern + Known or expected AE response pattern  
Probable  
Temporal pattern + Known or expected AE response pattern + Could not  
 
 
be explained by participant’s clinical state 
Possible   
Temporal pattern + Known or expected AE response pattern + Could  
 
 
have been produced by a number of other factors 
Unknown   
Relationship for which no evaluation can be made. 
Not related 
AE for which sufficient information exists to indicate that the cause is  
 
 
unrelated to the study intervention 
 
The study PI and Co-investigators will notify the IRB of any serious adverse events that result in 
death or on site events that result in medical care within 24 hrs of being made aware of the 
serious adverse event. 
 
Participant Compensation for Time and Travel:  
The participants in this study are partners in this research. We will provide each participant with 
a stipend of $125.00 funds to defray cost of travelling time investment during a work week, and 
parking at the OSMI.   
 
 
Possible Benefits:  
The study participants may gain some insight into their own gait and balance abilities, as each 
participant will receive a copy of their normal walking gait report without the foot device after 
they are done participating in the study.   
 
Analyze the risk-benefit ratio: 
This study provides little risks to individuals.  It poses a very low risk of breach of PHI.  The risk-
benefit ratio is acceptable. 
 
Conflict of Interest: 
This study is being sponsored by Villency Design Group, LLC. to determine the proof of action 
of their foot device design.   
 
 

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Statistics description: 
All statistics were performed on SPSS v 25.0. Descriptive statistics were performed on participant 
characteristics and opinions of orthotics on foot motion and health (means and standard deviations or % 
of the group). Repeated measures analysis of variance were used to determine whether significant 
improvements in the main functional outcomes (temporalspatial parameters of gait, ground reaction 
forces, loading rate and joint moments, foot pressure patterns, balance assessments [amount of center 
of mass sway in antero-posterior and medial-lateral directions and velocities of sway in different 
directions) occurred over time point (baseline, week 1). Effect sizes of the foot device on the key 
functional variables was determined using Cohen’s d. Safety measures of lower extremity muscle 
soreness and pain were reported as means for each day of the study. Significance was established in 
advance for all tests at p<0.05.