A Low-Cost, Collaborative Tool for the Tracking of Youth Activities to Reduce Risk of Physical Injury
Phase: NA
Conditions: Overuse Injury
Sponsor: Children's Hospital of Philadelphia

 
 
 
Title: 
A Low-Cost, Collaborative Tool for the Tracking of Youth 
Activities to Reduce Risk of Physical Injury 
Short Title 
Throwing Device Trial 
Regulatory Sponsor: 
National Institute of Health 
eIRB Number 
19-016149 
Protocol Date:  
3/23/2021 
Amendment 1 Date:  
Amendment 3 Date:  
Amendment 2 Date: 
Amendment 4 Date: 
 
 
J. Todd R. Lawrence, MD, PhD 
The Children’s Hospital of Philadelphia 
Wood Building, 2nd Floor 
Philadelphia, PA, 19104 
Phone 215-590-1535 
Email: lawrencej@chop.edu 
 
Elliot Greenberg, PT, DPT, PhD 
The Children’s Hospital of Philadelphia 
Sports Medicine & Performance Center 
Philadelphia, PA 19104 
Phone 215-590-6915 
Email: greenberge@email.chop.edu  
 
 
 

  
 
 
 
 
 
 
 
ii
TABLE OF CONTENTS 
Table of Contents ................................................................................................................... ii 
Abbreviations and Definitions of Terms............................................................................. iv 
Abstract .................................................................................................................................. v 
Table 1: Schedule of Study Procedures .............................................................................. vi 
1 
BACKGROUND INFORMATION AND RATIONALE ......................................................................... 1 
1.1 
INTRODUCTION ........................................................................................................................................ 1 
1.2 
NAME AND DESCRIPTION OF INVESTIGATIONAL PRODUCT OR INTERVENTION ........................................ 1 
1.3 
RELEVANT LITERATURE AND DATA ........................................................................................................ 2 
1.4 
COMPLIANCE STATEMENT ....................................................................................................................... 2 
2 
STUDY OBJECTIVES ................................................................................................................................ 2 
2.1 
PRIMARY OBJECTIVE (OR AIM) ................................................................................................................ 2 
2.2 
SECONDARY OBJECTIVES (OR AIM) ......................................................................................................... 2 
3 
INVESTIGATIONAL PLAN ...................................................................................................................... 3 
3.1 
GENERAL SCHEMA OF STUDY DESIGN ..................................................................................................... 3 
3.1.1 
Screening Phase .............................................................................................................................. 3 
3.1.2 
Pilot Phase: Physical Therapy Throwing Session ........................................................................... 4 
3.1.3 
Phase 1: Research Facility Throwing Session................................................................................. 4 
3.3 
STUDY DURATION, ENROLLMENT AND NUMBER OF SITES ...................................................................... 4 
3.3.1 
Duration of Study Participation ...................................................................................................... 4 
3.3.2 
Total Number of Study Sites/Total Number of Subjects Projected .................................................. 4 
3.4 
STUDY POPULATION ................................................................................................................................ 4 
3.4.1 
Inclusion Criteria ............................................................................................................................ 4 
3.4.2 
Exclusion Criteria............................................................................................................................ 4 
4 
STUDY PROCEDURES .............................................................................................................................. 5 
4.1 
SCREENING VISIT ..................................................................................................................................... 5 
4.2 
STUDY TREATMENT PHASE ..................................................................................................................... 6 
4.2.1 
Pilot Phase Study Visit .................................................................................................................... 6 
4.2.2 
Phase 1 Study Visit .......................................................................................................................... 6 
4.3 
SUBJECT COMPLETION/WITHDRAWAL ..................................................................................................... 7 
5 
STUDY EVALUATIONS AND MEASUREMENTS................................................................................ 7 
5.1 
SCREENING AND MONITORING EVALUATIONS AND MEASUREMENTS ...................................................... 7 
5.1.1 
Medical Record Review ................................................................................................................... 7 
5.1.2 
Physical Examination ...................................................................................................................... 7 
5.1.3 
Other Evaluations, Measures .......................................................................................................... 8 
5.1.4 
Pilot Phase Throwing Evaluations .................................................................................................. 8 
5.1.5 
Phase 1 Throwing Evaluations ........................................................................................................ 8 
5.2 
EFFICACY EVALUATIONS ......................................................................................................................... 9 
5.2.1 
Diagnostic Tests, Scales, Measures, etc. ......................................................................................... 9 
5.3 
SAFETY EVALUATION ............................................................................................................................ 10 
6 
STATISTICAL CONSIDERATIONS ...................................................................................................... 10 
6.1 
PRIMARY ENDPOINT .............................................................................................................................. 10 
6.2 
SECONDARY ENDPOINTS........................................................................................................................ 10 
6.3 
STATISTICAL METHODS ......................................................................................................................... 10 
6.3.1 
Baseline Data ................................................................................................................................ 10 
6.3.2 
Efficacy Analysis............................................................................................................................ 10 
6.3.4 
Safety Analysis ............................................................................................................................... 11 
6.4 
SAMPLE SIZE AND POWER ..................................................................................................................... 11 

 
 
 
 
 
 
 
 
iii
7 
SAFETY MANAGEMENT ....................................................................................................................... 11 
8.1 
CLINICAL ADVERSE EVENTS ................................................................................................................. 11 
8.2 
ADVERSE EVENT REPORTING ................................................................................................................ 11 
8 
STUDY ADMINISTRATION ................................................................................................................... 11 
9.1 
TREATMENT ASSIGNMENT METHODS .................................................................................................... 11 
9.2 
DATA COLLECTION AND MANAGEMENT................................................................................................ 11 
9.3 
CONFIDENTIALITY ................................................................................................................................. 12 
9.4 
REGULATORY AND ETHICAL CONSIDERATIONS ..................................................................................... 13 
9.4.1 
Data and Safety Monitoring Plan .................................................................................................. 13 
9.4.2 
Risk Assessment ............................................................................................................................. 13 
9.4.3 
Potential Benefits of Trial Participation ....................................................................................... 13 
9.4.4 
Risk-Benefit Assessment ................................................................................................................ 13 
9.5 
RECRUITMENT STRATEGY ..................................................................................................................... 13 
9.6 
INFORMED CONSENT/ASSENT AND HIPAA AUTHORIZATION ................................................................ 14 
9.7 
PAYMENT TO SUBJECTS/FAMILIES ......................................................................................................... 14 
9.7.1 
Reimbursement for travel, parking and meals ............................................................................... 14 
9.7.2 
Payments to parent for time and inconvenience (i.e. compensation) ............................................ 14 
9.7.3 
Payments to subject for time, effort and inconvenience (i.e. compensation) ................................. 14 
9 
PUBLICATION ........................................................................................................................................ 16 
10 
REFERENCES ......................................................................................................................................... 17 
 11 APPENDIX ............................................................................................................................................... 17 
11.1 PROPOSED DEVICE OVERVIEW .............................................................................................................. 19 
 
 

  
 
 
 
 
 
 
 
iv
ABBREVIATIONS AND DEFINITIONS OF TERMS 
 
 
 
AE 
 
Adverse event 
IDL 
 
Innovative Design Labs 
CHOP 
 
Children’s Hospital of Philadelphia 
IR 
 
Infrared  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

  
 
 
 
 
 
 
 
v
ABSTRACT 
Context:   
With the rise in competitive sports participation in pediatric and adolescent populations, 
there has also been an increase in overuse injuries. Current methods of overuse injury 
prevention, such as pitch-counting, fail to account for differing techniques or effort and 
often ignore the elevated risk for children participating in two or more sports emphasizing 
the same body part. This wearable device seeks to more accurately monitor overuse to 
prevent and aid rehabilitation of overuse injuries. 
Objectives:  
The primary objective of this study is to collect motion-capture data on movements common 
to baseball play in order to develop an algorithm for a wearable device for the prevention 
and rehabilitation of sports-related overuse injuries. Secondary objectives include evaluating 
the feasibility of wearing the throwing device during simulated baseball play. 
Study Design:  
Prospective reliability study. 
Setting/Participants: 
• Males and female baseball pitchers age 8-14 years old at the time of consent will be 
included 
• Children with an existing injury in their throwing arm will be excluded 
Data collection for the Pilot Phase will occur at sports medicine/physical therapy sessions at 
the Children’s Hospital of Philadelphia, including satellite locations. Participants may be 
approached at the start of their physical therapy sessions at CHOP. Data collection for Phase 
1 will occur at the Epic Sports Biomechanics research facility. Participants will be recruited 
via solicitation from letters sent to local youth sport organizations, fliers placed in the Sports 
Medicine Centers throughout CHOP, or personal solicitation via email, phone, or in-person 
contact. 
Study Interventions and Measures:  
Subjects will be asked to fill out a short survey about their athletic activities. They will wear 
a prototype of a minimal risk throwing device during simulated baseball play in a sports 
medicine session or at the Epic Sports Biomechanics research facility. Various motion data 
from the device and from the Motion Lab analysis will be collected to create and refine an 
algorithm to quantify workload and throwing movements. 

 
vi 
  
 
 
 
TABLE 1: SCHEDULE OF STUDY PROCEDURES 
Study Phase 
Screening 
Pilot 
Phase 
Screening 
Phase 1 
Pilot Phase: 
Physical 
Therapy Data 
Collection 
Phase 1: Epic 
Sports  
Collection 
Visit Number 
 
 
1 
1 
Informed Consent/Assent 
X 
X 
 
 
Review Inclusion/Exclusion 
Criteria 
X 
X 
 
 
Medical Record Review 
 
 
X 
 
Athletic History Survey 
 
X 
X 
 
Demographics Survey  
 
X 
 
 
Height/Weight 
 
 
X 
X 
Physical Examination 
 
 
X 
X 
Throwing Exercises with 
Device 
 
 
X 
X 
Epic Sports Biomechanics 
Evaluation 
 
 
 
X 
 
 
 
.

 
  
 
 
 
1
1 
BACKGROUND INFORMATION AND RATIONALE 
1.1 Introduction 
Overuse injuries in youth athletes are commonplace. Current methods of prevention and 
progressive loading during rehabilitation are rudimentary (e.g. baseball pitch count) and fail 
to account for the subtleties of differing player technique or effort. A system capable of 
quantifying biomechanical loads associated with sports movements would substantially aid 
physicians, therapists, guardians, and coaches in prevention and rehabilitation efforts.  
Study team partners at Innovative Design Labs (IDL) in collaboration with Reality Works 
Inc. have developed a prototype for an advanced wearable device that has potential to track 
cumulative exposure to injurious forces, monitor adherence to sport-specific overuse 
standards and rehab regimens, and identify improper throwing technique. The purpose of 
this study is to collect preliminary and advanced motion data from youth athletes in order to 
create and refine an algorithm to quantify throwing movements, numbers, and injury 
associations among youth baseball players for use in this wearable throwing monitor. The 
Pilot Phase of the study will occur in the CHOP rehabilitation clinic while wearing the 
prototype device and aims to test and refine rudimentary throwing algorithms using simple 
throwing and movement tasks. Phase 1 of the study will occur at the Epic Sports 
Biomechanics research facility and will collect advanced motion-capture data during 
simulated baseball play in order to improve system hardware, firmware, and algorithms.  
 
1.2 Name and Description of Investigational Product 
This sports injury performance monitoring device aims to 1) track exposure to injurious 
forces 2) monitor adherence to sport specific overuse standards and prescribed rehab 
regimens, 3) identify improper technique, and 4) meet the practical requirements of a youth-
sports monitoring system (e.g. cost, aesthetics, ease-of-use, etc.). An accompanying smart 
phone application and web interface will be developed as part of the study for use in future 
product development. More information on the electronic hardware and software can be 
found in the Appendix, page 20. 
As the comfort, ease-of-use, robustness, and appearance of any wearable device is of critical 
importance to its acceptance, significant effort will be put into analyzing the requirements 
and testing concepts for the device design in this study phase. Perfecting design and 
manufacturability will occur in a future study. The sensors will be sealed in soft, 
hypoallergenic foam to provide resistance to sweat, dirt, and physical impact. Multiple form-
factors including arm-bands, elbow compression sleeves, and wrist straps will be 
investigated, optimizing the combination of easy donning and doffing, maximal comfort, 
aesthetics, and to accurate motion transfer. The system will include a “zero touch” interface 
where no user interaction is required to utilize the device. Study team members will be 
responsible for setting up, powering up, and charging the device.The case will be 
hermetically sealed creating a dust-tight and waterproof device (IP68 rated). 
 

 
  
 
 
 
2
1.3 Relevant Literature and Data 
Youth sports participation in the United States has grown to 46.5 million children annually 
[1]. Although participation in athletics has numerous health benefits [2], sport-related 
overuse injuries from excessive stress and/or inadequate recovery periods represent a 
significant and growing health care concern [3]. Annually, 1.25 million sports-related 
overuse injuries are reported in emergency rooms with patients 24 years or younger [4] 
resulting in $2 billion of healthcare costs [3], [8]–[11]. In addition to cost and pain, these 
injuries result in lost participation time, numerous physician visits, and lengthy rehabilitation 
[2]–[5]. Further, athletes with recurrent overuse injuries may stop participating in sports, 
thus adding to the already increasing numbers of unhealthy sedentary and obese youths [3]. 
Overuse injuries are preventable through proper monitoring and education; however, 
adherence to guidelines is often deficient [6]. This device seeks to prevent and aid 
rehabilitation of such sports-related overuse injuries.  
 
1.4 Compliance Statement 
This study will be conducted in full accordance all applicable Children’s Hospital of 
Philadelphia Research Policies and Procedures and all applicable Federal and state laws and 
regulations including 45 CFR 46 and 21 CFR Parts 50, 56. 
The investigators will perform the study in accordance with this protocol, will obtain 
consent and assent, and will report unanticipated problems involving risks to subjects or 
others in accordance with The Children’s Hospital of Philadelphia IRB Policies and 
Procedures and all federal requirements. Collection, recording, and reporting of data will be 
accurate and will ensure the privacy, health, and welfare of research subjects during and 
after the study.  
2 
STUDY OBJECTIVES 
The overall purpose of the study is to create and refine an algorithm to quantify throwing 
movements, effort, numbers, and injury associations among youth baseball players for use in 
a wearable throwing monitor with the hopes of preventing and aiding in the rehabilitation of 
sports-related overuse injuries. 
2.1 Primary Objective (or Aim) 
The primary objective of this study is to collect motion-capture data on movements common 
to baseball play in order to develop a wearable device for the prevention and rehabilitation 
of sports-related overuse injuries.  
2.2 Secondary Objectives (or Aim) 
The secondary objectives are to: 
• 
Develop algorithms to quantify injury associated with common baseball injures 
• 
Evaluate the feasibility of wearing the throwing monitor during a simulated baseball 
game 

 
  
 
 
 
3
• 
Validate simplistic device measurements (Pilot Phase) 
 
3 
INVESTIGATIONAL PLAN 
3.1 General Schema of Study Design 
This study will occur in two phases with two different subject groups. The Pilot Phase will 
include 10 evaluable subjects and occur in the sports medicine physical therapy clinic at the 
Children’s Hospital of Philadelphia. Subjects will be asked to perform simple throwing 
movements as part of or in addition to their rehabilitation regiment. This will test the ability 
of the prototype device to detect basic movements. 
Phase 1 will include 10 evaluable subjects and occur at the Epic Sports Biomechanics 
research facility. Subjects will partake in a simulated baseball game while wearing the 
prototype device and additional baseball-related movements while being tracked by the Epic 
Sports Biomechanics research facility’s infrared sensors. The goal of this phase is to create 
and refine a more robust algorithm for the device that can track various throwing 
movements and track potential injurious forces or poor techniques. 
This study is a prospective reliability study.  
3.1.1 Screening Phase 
Pilot Phase: Potential subjects will be identified from screening patient lists for CHOP sports 
medicine/physical therapy sessions. Potential subjects will be screened using the protocol 
inclusion and exclusion criteria. Subjects will be consented in-person at the start of their 
physical therapy session. 
Phase 1: Potential subjects will be identified through recruitment strategies outlined in 
Section 8.5. Subjects will be screened over the phone, over email or in person using the 
protocol inclusion and exclusion criteria. Subjects will have the study explained to them and 
have opportunity to ask questions over the phone or in person and will sign a REDCap 
consent form sent to them via email. Once the consent form is signed, the study team will 
work with the subject to schedule a session at the Epic Sports Biomechanics research 
facility. 
For both phases, parental/guardian permission (informed consent) and child assent, will be 
obtained prior to any study related procedures being performed. 
3.1.2 Pilot Phase Cohort: Physical Therapy Throwing Session 
During the Pilot Phase, subjects that have been identified, consented, and enrolled will wear 
a prototype of IDL’s throwing monitor device during the duration of their physical therapy 
appointment. Subjects will wear the device somewhere on their arm and may or may not be 
asked to perform throwing movements as part of their rehabilitation regimen. This phase 
will test if the device is able to detect basic throwing movements and create an accurate 
pitch count. 

 
  
 
 
 
4
3.1.3 Phase 1 Cohort: Epic Sports Biomechanics Throwing Session 
During Phase 1, subjects that have been recruited, consented, and enrolled will come to the 
Epic Sports Biomechanics research facility on the day of their appointment. Subjects will be 
asked to wear the prototype device during a simulated baseball game (approximately 30-45 
pitches), and then will perform a set of other baseball-specific movements while fitted with 
infrared markers for throwing analysis. This data will be used to develop and refine the 
algorithm for the prototype. 
3.2 Study Duration, Enrollment and Number of Sites 
3.2.1 Duration of Study Participation 
The study duration per subject will be 1 day for screening, and 1 day for throwing evaluation 
for both the Pilot and Phase 1 groups.  
3.2.2 Total Number of Study Sites/Total Number of Subjects Projected 
The study will be conducted at approximately 3 investigative site in the United States: The 
Children’s Hospital of Philadelphia, Epic Sports Biomechanics, and the University of 
Pennsylvania. Data will also be transferred to and analyzed at the University of 
Pennsylvania. 
Recruitment will stop when approximately 40 total subjects are recruited. It is expected that 
approximately 40 subjects will be enrolled to produce 20 evaluable subjects, with 10 in the 
Pilot Group and 10 in the Phase 1 Group.  
3.3 Study Population 
3.3.1 Inclusion Criteria 
Pilot Phase 
1) Males or females age 8 to 14 years 
2) Presenting to CHOP Physical Therapy Clinic for rehabilitation of injury that does not 
impede their ability to perform basic throwing movements. 
Phase 1 
1) Males or females age 8 to 14 years 
 
2) Involved in official baseball team and primarily plays as the pitcher  
 
3.3.2 Exclusion Criteria 
Pilot Phase 
1) Injury of any aspect of the throwing arm 
2) Unwillingness to perform all requested motions 

 
  
 
 
 
5
3) Parents/guardians or subjects who, in the opinion of the Investigator, may be non-
compliant with study procedures. 
Phase 1 
1) Injury or disability impeding ability to perform normal baseball-related movements 
2) Inability/unwillingness to schedule and/or travel to the Epic Sports Biomechanics 
research facility 
3) Parents/guardians or subjects who, in the opinion of the Investigator, may be non-
compliant with study schedules or procedures. 
Subjects that do not meet all of the enrollment criteria may not be enrolled. Any violations 
of these criteria must be reported in accordance with IRB Policies and Procedures.  
4 
STUDY PROCEDURES 
4.1 Screening Visit 
4.1.1 Pilot Phase 
The screening visit will occur on the day of clinic and any screening procedures (e.g. 
informed consent) will happen in-person. Procedures include: 
• Review of inclusion/exclusion criteria 
• Medical Record Review 
4.1.2 Phase I cohort 
For the Phase 1 cohort, the screening visit will occur over the phone or in-person. Screening 
procedures include: 
• Informed consent (via electronic consent on REDCap distributed through email) 
o Study explanation and time for the potential subject to ask questions will 
occur over the phone or in person with a member of the study team 
o Subjects will be emailed an electronic consent form through REDCap, which 
will contain all consent-form language for their review and space for an 
electronic signature 
• Demographics survey (on REDCap, distributed through email after consent form is 
received and verified) 
• Complete athletic history survey (on REDCap, distributed through email after 
consent form is received and verified) 
• Review of inclusion/exclusion criteria 

 
  
 
 
 
6
4.2 Study Treatment Phase 
4.2.1 Pilot Phase Study Visit 
• Informed consent and assent 
Subjects will be asked to put on the throwing monitor device prototype at the beginning of 
their physical therapy session and will wear the device for the duration of the visit or until 
asked by a member of the study team to remove the device. Subjects will be asked to do the 
following tasks while wearing the device: 
• Complete any physical therapy rehabilitation exercises given by their physical 
therapist as part of their care 
• Complete a limited number of additional throwing exercises within in the limits of 
the rehabilitation regimen 
• Complete athletic history survey (not required to wear device for survey completion) 
• Medical record review 
• Height and weight measurements if not collected as part of clinical care 
• Physical exam if not collected as part of clinical care 
• Return throwing device at end of session or earlier if requested by study team 
No subject will be asked to complete any motions or tasks that may hinder their 
rehabilitation regimen. 
4.2.2 Phase 1 Study Visit 
At the Epic Sports Biomechanics research facility, subjects will be asked to do the following 
activities: 
• Height and weight measurements 
• Physical Exam 
• Wear the prototype device and participate in a simulated game 
o Pitch approximately 30-45 times using varying pitch types (fastball, change-
up, etc.) 
• Complete additional baseball-related movements with full the Epic Sports 
Biomechanics research facility monitors in a random order, including 
o Field-based overhand throws 
o Runs 

 
  
 
 
 
7
o Bat swings 
o Catching balls 
• Return throwing device at end of session or earlier if requested by study team 
4.3 Subject Completion/Withdrawal 
Subjects may withdraw from the study at any time without prejudice to their care (if 
applicable). They may also be discontinued from the study at the discretion of the 
Investigator for lack of adherence to study protocols (i.e. wearing the device at appropriate 
times), failure to follow visit schedules, injury that prevents the subject from throwing or 
participating in the study, or any AEs. The Investigator may also withdraw subjects who 
violate the study plan, or to protect the subject for reasons of safety or for administrative 
reasons. It will be documented whether or not each subject completes the clinical study. If 
the Investigator becomes aware of any serious, related adverse events after the subject 
completes or withdraws from the study, they will be recorded in the source documents and 
on the CRF. 
5 
STUDY EVALUATIONS AND MEASUREMENTS 
5.1 Screening and Monitoring Evaluations and Measurements 
5.1.1 Medical Record Review 
Patients enrolled in the Pilot Phase will undergo limited electronic medical record review of 
the following variables: 
• Date of birth 
• Height and weight 
• Demographics including sex and race 
• Primary diagnosis  
• Prescribed physical therapy 
• Medical history of current and previous injuries  
Patients enrolled in Phase 1 will not necessarily be CHOP patients and thus will not undergo 
medical record review, but will instead be given a brief demographic survey. 
5.1.2 Physical Examination 
Subjects in both phases will be asked about current and past injuries. Subjects in the Pilot 
Phase will undergo a physical examination if not part of clinical care. The subjects in Phase 
1 will also undergo a physical examination by the team prior to engaging in throwing 
activities. For both phases, we will be assessing height and weight as well as range of 
motion, strength, balance and other physical assessment measures involving the kinetic 

 
  
 
 
 
8
chain that may lead to alterations in throwing technique and correspond to an increased risk 
of injury. Specific measurements may include range of motion of shoulder, elbow, spine, 
hip, and ankle; assessment for scapular dyskinesis; strength assessment through the 
shoulder, elbow, trunk and hip and lower extremities; single leg balance; humeral 
retrotorsion using musculoskeletal US will also be assessed using validated techniques.    
5.1.3 LifeIMAGE/iSite 
Any imaging records associated with the subjects in the Pilot Phase will be reviewed. 
5.1.4 Other Evaluations, Measures 
Subjects in both phases will be asked to complete a brief survey on their athletic history. The 
survey will ask about their athletic team involvement and injury history and should take no 
more than five minutes to complete. Subjects will not have to answer any questions that 
make them uncomfortable. This may be completed on REDCap or on paper for the Pilot 
Phase. Paper forms will then be entered into REDCap by a member of the study team and 
hard copies will be destroyed. Subjects in Phase 1 will receive the survey via email after the 
completed consent form has been received. 
Subjects in Phase 1 will be asked to complete a brief demographic survey on REDCap, 
which will be sent to them via email after the study team has received their signed consent 
form. This survey will ask basic demographic information such as date of birth, race, and 
ethnicity. 
5.1.5 Pilot Phase Throwing Evaluations 
Subjects will wear the throwing monitor device prototype during a physical therapy session 
unless asked by a member of the study team to remove it. They will go through all of their 
normal physical therapy exercises. In addition, subjects may be asked to do a limited 
number of additional throwing movements during their physical therapy session. Subjects 
will not have to interact with the device other than donning and doffing the device. The 
device will collect motion data for the duration of the session. Subjects will not be asked to 
complete any additional exercises that could hinder their rehabilitation program. Subjects 
will be asked to return the throwing monitor device by the end of the study visit. 
5.1.6 Phase 1 Throwing Evaluations 
At the Epic Sports Biomechanics research facility, subjects will wear the throwing monitor 
device prototype during a simulated baseball game, pitching approximately 30-45 times 
using varying pitch types (fastball, change-up, etc.) as they would within a typical game. In 
addition, each player will perform a set of other baseball-specific movements (field-based 
overhand throw, run, bat swing, catch ball) typically seen in baseball play. Participants will 
be fitted with 51 infrared reflective markers to enable tracking of limb, torso, and head 
movement while actions are performed. Movement data will be video recorded and recorded 
with 12 Motion Analysis Raptor IR cameras encompassing a capture volume of 26ft length 
x 7ft width x 8ft height. A minimum of 3 time-synchronized video cameras placed at 
different viewing perspectives will also record participants as they perform movements. 
Subjects will be asked to return the throwing monitor device by the end of the study visit. 

 
  
 
 
 
9
5.2 Efficacy Evaluations 
5.2.1 Diagnostic Tests, Scales, Measures, etc. 
Movement Data Processing: The first step in the processing chain is to apply calibrations 
and filters to correct intrinsic errors (e.g. sensor bias, scale factor, non-linearity) and 
extrinsic errors (e.g. sensor mounting, movement artifacts, external magnetic fields). This 
will be done using an Error-State Extended Kalman Filter (EKF) fusing the accelerometer, 
gyroscope, magnetometer, and a physical motion model together in a statistically valid 
fashion. Anomalous movements well outside of the expected range (e.g. a player bumping 
the sensor) are flagged by the sensor to avoid corrupting data interpretation. The filtered 
sensor data is then used to estimate time-series quantities such as short-time window 3-D 
motion paths, orientation stability, velocity vectors, and tangential and centripetal 
accelerations.  
Movement Classification: The system is only interested in analyzing a subset of the 
movements executed during play hence the next step in the processing chain is detection / 
classification of movements of interest. This process begins with separation of processed 
time-series data into portions containing movements of unknown type. This is done with a 
classifier trained to discriminate fixed sized windows into either start of movement, end of 
movement, or other classes. This separation process is important as different actions will on 
average take differing amounts of time. Attempting to classify actions directly with fixed 
window sizes results in diminished discriminative power as the timeseries values used to 
produce these features will likely be taken from a period where the system is in multiple 
states [39], [40]. After action segmentation, a secondary feature set will be calculated over 
the movement timeseries and used to classify the movement to a known class of actions in 
the given sport (e.g. forehand swing, backhand swing, serve in tennis). IDL has had success 
with the decision tree classifier in previous efforts and will begin our research efforts with 
this algorithm. The tree is trained offline using the C4.5 algorithm with data acquired in the 
research facility [41]. The resulting decision trees are then used for real-time classification 
on the sensor hardware.  
Movement Phase Segmentation: After detection and classification, movements are further 
segmented into constituent phases. The true phase of the movement is modeled as a hidden 
Markov model where time series data or windowed feature data derived from the time series 
data are used as emissions of the Markov process. Using the set of emissions recorded, the 
optimal set of series of states is calculated using the Viterbi algorithm [2]. Emissions 
distributions for the phases of a movement are determined from truth data gathered in the 
Epic Sports Biomechanics research facility. 
Biomechanical interpretations: Pseudo Biomechanical Variables (PBVs) related to the true 
biomechanical values such as torques on joints and forces applied to ligaments are estimated 
at the final stage in the processing pipeline. This is accomplished using a combination 
regression analysis and a phase-specific simplified inverse biomechanical model. Since 
movement phases are associated with specific biomechanical configuration and 
displacements of the body segments within a phase are constrained by design, the inverse 
mapping is determined over a smaller problem subspace. Regression analysis is used offline 
to calculate a mapping between biomechanical values of interest (e.g. torque in shoulder) 
and sensor measurements (e.g. x dimension acceleration). The regression is simplified 
through use of the least absolute shrinkage and selection operator (LASSO) to determine the 

 
  
 
 
 
10 
minimum set of active joint variables to improve computational performance when executed 
on sensor hardware in real-time [42].  
These values are then used to determine the probability of injury as well as calculate 
performance estimates such as pitch velocity. PBVs are also paired with movement phase 
information, stored, and available for viewing by the player, parents, and coaches to aid in 
quick identification of problems with form or opportunities to improve performance. Injury 
estimation cost functions will score actions based on the potential for accumulated overuse 
injury risk. For example, large forces on the UCL during the stride phase of a baseball pitch 
due to an excessive rotation of the forearm from the horizon to the vertical plane would 
accumulate a higher cost than a similar pitch with proper form [43].  
5.3 Safety Evaluation 
This is a minimal risk study. The Principal Investigator will be responsible for monitoring 
the safety of study subjects and complying with all reporting requirements. Members of the 
study team who perform the motion analysis will monitor subjects throughout to ensure that 
they do so safely. The PI and study investigators will monitor data accuracy and identify 
ways to resolve any problem areas.  
6 
STATISTICAL CONSIDERATIONS 
6.1 Primary Endpoint 
• The primary endpoint of this study is to quantify motion capture data on movements 
common to baseball play. 
6.2 Secondary Endpoints 
Secondary endpoints will include the following:  
• Quantify injury associated with different baseball movement using the proposed system. 
• Development of algorithms to quantify workloads associated with injury during common 
baseball movements. 
• Validation of basic device measurements (Pilot Phase) 
 
6.3 Statistical Methods 
6.3.1 Baseline Data  
Data will be analyzed with the goal of determining the feasibility of the approach. The 
accuracy of movement classification, movement phase segmentation, mapping of sensor 
reading to biomechanical values, and movement detection will all be quantified. K-fold 
cross validation will be used to estimate the performance of regressors and classifiers. 
Regressor performance will be quantified via the mean and standard deviation of error 
values between predicted biomechanical variable values and actual values as determined 
from motion capture data. Biomechanical value prediction models will be considered 
successful if error distributions have mean and standard deviation of less than 5% and 10% 
respectively of the nominal value. Sensitivity and specificity will be used to quantify the 

 
  
 
 
 
11 
performance of movement detection and classification algorithms. Movement segment 
detection will be considered correct if the algorithm identifies 90% of time occupied by the 
movement. Detection algorithms will be considered successful if they are able to operate 
with specificity and sensitivity of 95%. 
6.3.2 Efficacy Analysis 
Data recorded from the motion capture system will be analyzed with C-Motion Research 
Visual 3D v5 Professional and used to derive biomechanical variables of interest when 
performing movements associated with overuse injuries or of interest for performance 
monitoring. Analysis will calculate a time series of torques, compression forces, and tension 
forces on joints, ligaments, and muscles of interest. A biomechanist at the Epic Sports 
Biomechanics research facility familiar with baseball will review video of each movements 
of interest (e.g. pitches) and segment movements into their constituent phases. Additionally, 
the biomechanist will flag any abnormalities in data such as aborted movements and 
instances of improper form or technique. 
6.3.3 Safety Analysis 
This is a minimal risk study. The Principal Investigator will be responsible for monitoring 
the safety of study subjects and complying with all reporting requirements. Members of the 
study team who perform the motion analysis will monitor subjects throughout to ensure that 
they do so safely. The PI and study investigators will monitor data accuracy and identify 
ways to resolve any problem areas.  
6.4 Sample Size and Power 
This is an exploratory study so no power analysis was conducted. A total of 40 patients will 
be enrolled study-wide. For the pilot phase, we plan to enroll 20 patients to yield 10 
evaluables. Additionally, based on previously reported literature, we plan to enroll a 
convenience sample of 20 youth baseball players in Phase 1 to yield 10 evaluable subjects, 
mainly consisting of pitchers, will be recruited to participate in this study. However, to 
account for subject withdrawal and attrition rates, study team plans to enroll additional 10 
more subjects per phase.  
7 
SAFETY MANAGEMENT 
7.1 Clinical Adverse Events 
Clinical adverse events (AEs) will be monitored throughout the study.  
7.2 Adverse Event Reporting 
Since the study procedures are not greater than minimal risk, SAEs are not expected. If any 
unanticipated problems related to the research involving risks to subjects or others happen 
during the course of this study (including SAEs) they will be reported to the IRB in 
accordance with CHOP IRB SOP 408: Unanticipated Problems Involving Risks to Subjects. 
AEs that are not serious but that are notable and could involve risks to subjects will be 
summarized in narrative or other format and submitted to the IRB at the time of continuing 
review.  

 
  
 
 
 
12 
8 
STUDY ADMINISTRATION 
8.1 Treatment Assignment Methods 
8.2 Data Collection and Management 
1. Confidentiality of Data. A master list will be maintained separately from the data 
collection sheet and will contain identifiable data including subject ID, name, DOB 
and MRN (if applicable). The study team members will be the only individuals with 
access to the master list. All other data will be collected on a separate coded data 
collection sheet– only the study ID number will link the master sheet to the coded 
data sheet. Both the master list and coded data collection sheet will be password-
protected excel files. Data will be managed and stored using the research-focused 
electronic data capture system REDCap, under an agreement with the software’s 
development consortium, led by Vanderbilt University. REDCap supports two 
secure, web-based applications designed exclusively to support data capture for 
research studies. REDCap is a PHP web application served by Apache Tomcat over 
a 128 bit SSL connection using a signed certificate. The application relies on a study-
specific data dictionary defined in an iterative self-documenting process that will be 
conducted by all members of the research team. The data dictionary is the foundation 
for custom case report form design and validated coding of variables. Authentication 
of research staff will be performed via LDAP using CHOP’s enterprise Active 
Directory service. The application generates a complete audit trail of user activity, 
provides reporting, and has an automated export mechanism to common statistical 
packages (SAS, SPSS, Stata, R/S-Plus).  
2. Security. The master sheet and data collection sheet will be password protected 
excel files kept in the secure storage network for the Division of Orthopaedics on the 
secure hospital server. The REDCap MySQL database is replicated in real time to a 
completely redundant instance of MySQL.  The redundant instance is available for 
restoration of the primary database or for manual failover in the case of primary 
database failure.  Time-stamped backup files are made from the replicated database 
daily by CHOP Research Information Systems using automated backup routines.  
Backup files are encrypted and transferred to a secure file server accessible only to 
designated personnel.  A rolling seven-day window of backup files is maintained in 
an immediately available online state, with a larger window maintained in a 
compressed file archive available at a reduced speed of access.  Daily destructive 
database backup files are stored on the database server and are deleted only after 
successful backup of the entire database to file.  In the event of data error, loss or 
corruption, research personnel will work with CHOP Research Information Systems 
to determine the most appropriate recovery strategy. Data and backups are stored in 
the CHOP Research Information Systems Storage Area Network (SAN).  Access to 
the SAN directories where data are stored will be limited to Research Information 
Systems personnel, with authentication performed using CHOP’s enterprise Active 
Directory service. Consent forms from the Pilot Phase will be stored electronically 
on the secure orthopaedics hard drive or a hard-copy will be kept in a binder in the 
locked research office. Consent forms from Phase 1 will be stored in REDCap. All 
data collected from the throwing device or at the Epic Sports Biomechanics research 

 
  
 
 
 
13 
facility will be secured electronically or in locked cabinets only accessible to 
research personnel. Processed data collected in the Epic Sports Biomechanics 
research facility will be transferred to research staff at CHOP and the University of 
Pennsylvania as coded, password-protected excel files sent via secure email servers 
or CHOP’s secure ShareFile functionality. Any processed or unprocessed data from 
the throwing device and/or Epic Sports Biomechanics analysis will be transferred to 
CHOP or the University of Pennsylvania before being sent via secure email servers, 
an encrypted flash drive, or CHOP’s ShareFile function to collaborators outside of 
CHOP or the University of Pennsylvania where it will be stored securely in 
password-protected computers or drives. 
3. Anonymization, de-identification or destruction. The information collected as part 
of this study will be retained until at least two years following final marketing 
approval for the device according to FDA data retention guidelines. At that time, the 
research information will either be destroyed or all the information that identifies the 
subject will be removed from the study results and the key destroyed. 
8.3 Confidentiality 
All data and records generated during this study will be kept confidential in accordance with 
Institutional policies and HIPAA on subject privacy and the Investigator and other site 
personnel will not use such data and records for any purpose other than conducting the 
study. Data will be maintained in REDCap or in password-protected data files on password-
protected computers. Data transfers will be limited to within the study team and will utilize 
encrypted flash drive, secure email providers, and/or CHOP’s secure ShareFile function.  
No identifiable data will be used for future study without first obtaining IRB approval or a 
determination of exemption”. The investigator will obtain a data use agreement between the 
provider (the PI) of the data and any recipient researchers (including others at CHOP) before 
sharing a limited dataset (PHI limited to dates and zip codes).  
8.4 Regulatory and Ethical Considerations 
8.4.1 Data and Safety Monitoring Plan 
The principal investigator will monitor data and safety throughout the duration of the study.  
There is minimal safety risk associated with participation in this protocol, but the study team 
will immediately notify the PI if any safety issues do arise. The PI and study team will 
monitor data accuracy and identify ways to resolve any problem areas. 
8.4.2 Risk Assessment 
The risks of this study are no greater than minimal. Risks to study subjects are breach of 
privacy and/or breach of confidentiality. There is a minimal risk that survey questions may 
make subjects uncomfortable, but subjects do not have to answer any questions that make 
them feel uncomfortable. There is also a minimal risk that subjects may become injured 
while being asked to perform different throws and movements typical of physical therapy 
regimens or youth baseball play. However, this risk will be minimized because subjects will 
be under the supervision of a trained physical therapist and subjects will be able to 

 
  
 
 
 
14 
discontinue any throw/movement that makes them uncomfortable. Finally, there may be a 
risk of skin irritation from wearing the PhysSens device. 
8.4.3 Potential Benefits of Trial Participation 
There are no direct benefits to the subject related to this study.  
8.4.4 Risk-Benefit Assessment 
The risks of this study are no greater than minimal. While there is minimal risk to subjects 
due to accidental disclosure of PHI, this risk is minimized through the techniques outlined in 
the “Data Collection and Management” section. 
8.5 Recruitment Strategy 
Participants for the Pilot Phase will be recruited from orthopaedics physical therapy clinics 
at CHOP. Potential subjects will be identified by a member of the study team based on 
screening sports medicine physical therapy clinic schedules against the inclusion/exclusion 
criteria. Patients who are qualified for the study (based on the inclusion/exclusion criteria) 
will be approached and consented during their physical therapy visit. 
Participants for Phase 1 will be recruited from multiple sources including solicitation letters 
sent to local youth sport organizations, fliers placed in the Sports Medicine Centers 
throughout CHOP organization, and or personal solicitation via email, phone, or in-person 
contact. Patients who are qualified for the study (based on inclusion/exclusion criteria) and 
who respond to solicitation or other recruitment strategies will be consented via e-consent 
processes using REDCap and will have the opportunity to ask questions during a phone call 
with a member of the study team prior to signing the eConsent. At the biomechanics 
laboratory for throwing performance housed at Epics Sports Biomechanics, the subjects will 
undergo additional data collection within the 3-D motion laboratory in order to augment 
training data and re-estimate the accuracy of the various algorithmic components.  
For the Pilot Phase, a convenience sample of 20 youth athletes will be recruited to 
participate. Recruitment will stop when 10 evaluable subjects have undergone data 
collection. 
For Phase 1, a convenience sample of 20 youth baseball pitchers, will be recruited to 
participate in this study. Recruitment will stop when 10 evaluable subjects have undergone 
data collection.  
 
8.6 Informed Consent/Assent and HIPAA Authorization 
A member of the study team will obtain consent and assent from all eligible subjects and 
families that agree to participate in the research. For pilot phase, the consent and assent 
process will take place in physical therapy setting after a member of the study team has 
explained the research, clearly outlined the risks and benefits of participation, and provided 
the subjects and their families with sufficient time to ask questions and consider 
participation. Similarly, the participants for Phase 1 will be recruited via methods elaborated 
in Section 8.5 for a study session at th Epic Sports Biomechanics research facility. Subjects 

 
  
 
 
 
15 
in Phase 1 will be consented and provide assent via e-consent processes using REDCap and 
will have the opportunity to ask questions during a phone call with a member of the study 
team prior to signing the eConsent. All subjects will be under 18, so parental consent and 
child assent will be obtained. All subjects will be provided with a hard or digital copy of the 
consent form, which includes a description of the research and contact information for the 
study team. 
The Phase 1 eConsent will be administered via REDCap, and will grant parental 
permission/consent, child assent, and HIPPA authorization for screening procedures 
(questionnaires) for the main study within the same form. The consent form will be emailed 
to the address provided by the parent/legal guardian when discussing the study on the phone 
as detailed above, and a valid electronic signature will be obtained for parental consent and 
child assent. The subject will be able to save or print a copy of the signed as well as the 
unsigned consent form, and the form will have instructions on how to do so. 
 
8.6.1 Waiver of HIPAA Authorization 
We believe this study qualifies for a waiver of HIPAA authorization for the screening of 
subjects for the Pilot Phase, as the use or disclosure of protected health information involves 
no more than minimal risk to the privacy of individuals. This is due to the fact that there is 
an adequate plan to protect identifiers and to destroy identifiers at the earliest opportunity as 
noted in the section entitled “Data Collection and Management.” There is also a written 
assurance that protected health information will not be reused or disclosed to any other 
person or entity, except as required by law, for authorized oversight of the research project, 
or for other research for which the use or disclosure of protected health information would 
be permitted by this subpart as noted in the section entitled “Confidentiality.” The research 
cannot be practicably carried out without the waiver since it is not feasible for the study 
team to approach all subjects coming to the Sports Medicine Center for physical therapy 
prior to screening for eligibility. PHI is necessary to identify our target population and 
review medical records; therefore, this research could not be practicably carried out without 
access to this information.  
 
8.7 Payment to Subjects/Families 
8.7.1 Reimbursement for travel, parking and meals 
Subjects in Phase 1 only will receive free validated parking slips to cover the parking cost at 
the Penn Medicine University City lot near the gait lab. 
8.7.2 Payments to parent for time and inconvenience (i.e. compensation) 
No compensation will be provided to the parent.  
8.7.3 Payments to subject for time, effort and inconvenience (i.e. compensation) 
Subjects in Phase 1 only will receive $50 to compensate for time, effort, and inconvenience. 
Subjects in the Pilot Phase will not receive compensation as the study procedures will take 

 
  
 
 
 
16 
no more than 15 minutes beyond their indicated physical therapy visit for consent, surveys, 
and donning/doffing the device. 
9 
PUBLICATION 
Following the completion of data collection and analysis, manuscript(s) will be written and 
submitted for publication in appropriate journals. Abstracts will also be prepared for 
submission and presentation at relevant scientific meetings. Data may also be included in 
future grant applications. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
  
 
 
 
17 
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11 APPENDIX 
11.1 Proposed Device Overview 
From Grant Application, Pages 10-11. 
 
Starting with the IDL PhySens design, the custom electronics will swap the microSD Card holder for 
a solder-on eMMC memory IC to greatly reduce size and increase robustness. To sense the full 
dynamic range of various athletic activities (often exceeding accelerations of 60g) the updated device 
will include both low-range/high-resolution (ST LSM6DSL) and high-range/low-resolution 
(H3LIS331DL) triaxial accelerometers and gyros as well as a triaxial magnetometer (LIS2MDL) 
fused together through IDL’s Extended Kalman Filter. This approach allows a continual, smooth 
estimate of the motions throughout a large dynamic range. 
 
The sensor data will be processed by a Nordic Semiconductor nRF52840 RF SoC which includes an 
integrated Bluetooth Low Energy (BLE) Radio and ARM Cortex-M4F processor with floating point 
hardware. This processor will perform calculations, and transmit the compressed results wirelessly 
using a BLEv5 compatible stack. Using BLEv5 legacy features, the sensors can connect directly to 
nearly all smartphones produced since 2012. The new BLEv5 mesh networking capability, and 
“Long Range” mode of the BLEv5 network also allows sensors to communicate to the Team 
Communication Hub extend the range to over 200m between each player with a >110dBm link 
budget. When not connected to an internet enabled device (mobile phone or communication hub) 
data is stored locally. The sensor will provide status and activity information to the user through a 
segmented led “fuel bar”. 
 
It is expected that the time-averaged, total system draw when in use will be roughly 6.5mA during 
active play. A thin 100mAH rechargeable lithium polymer battery (2.8x2.8x1.4mm) will power the 
system for 15 hours of continuous use. To conserve power, the system will automatically shut off 
when periods of inactivity are detected. The battery will “fast-charge” through sealed contact points 
on a charging dock in “fast-mode” to reach 80% full charge in under 15mins. 
 
As the comfort, ease-of-use, robustness, and appearance of any wearable device is of critical 
importance to its acceptance, significant effort will be put into analyzing the requirements and testing 
concepts (phase 1) and then perfecting its design and manufacturability (phase 2). IDL is 
collaborating with Mr. Scott Melanson an expert in medical, wearable, and exercise equipment 
industrial design including on ongoing NIH Phase 2 SBIR to monitor motions of exercises to relieve 
low-back pain. The sensors will be sealed in soft, hypoallergenic foam to provide resistance to sweat, 
dirt, and physical impact. Multiple form-factors including arm-bands, elbow compression sleeves, 
and wrist straps will be investigated, optimizing the combination of easy donning and doffing, 
maximal comfort, aesthetics, and to accurate motion transfer. The system will include a “zero touch” 
interface where no user interaction is required to utilize the device. Power will be automatically 
managed based on the user’s actions—sleeping while not in use and waking up during play. The case 
will be hermetically sealed creating a dust tight and waterproof device (IP68 rated).