Brain-Computer Interface Visualization Training to Optimize Muscle Activation Following Orthopaedic Surgery: A Blinded Randomized Controlled Trial
Phase: PHASE2
Conditions: Anterior Cruciate Ligament Reconstruction, Total Hip Arthroplasty (THA), Total Knee Arthroplasty, Hip Arthroscopy
Sponsor: Rush University Medical Center

Brain-Computer Interface Visualization Training to Optimize Muscle Activation Following 
Orthopaedic Surgery 
 
NCT number: Not Assigned 
Unique Protocol ID: 24021101 
05/17/2025 
 

1. Abstract 
 
Postoperative recovery following orthopedic surgeries often faces challenges due to Arthrogenic 
Muscle Inhibition (AMI), a neurological condition that impairs muscle activation and hinders 
rehabilitation. This study investigates the effectiveness of visualization training with 
neurofeedback as a supplementary method to standard physical therapy in reducing AMI and 
improving functional recovery. Neurofeedback, utilizing electroencephalography (EEG), 
provides real-time feedback on motor cortex activation during mental visualization of 
movements. The study focuses on patients recovering from four orthopedic procedures—anterior 
cruciate ligament reconstruction (ACLR), total knee arthroplasty (TKA), total hip arthroplasty 
(THA), and hip arthroscopy (HA) for femoroacetabular impingement syndrome (FAIS). Using 
iBrainTech™ technology, we aim to assess improvements in muscle activation, range of motion, 
strength, and patient-reported outcomes. Findings could enhance rehabilitation protocols, 
accelerate recovery, and deepen understanding of neuroplasticity in motor control. 
 
2. Introduction 
 
Background 
 
Patients recovering from orthopedic surgical procedures require a comprehensive physical 
rehabilitation process to help recover pre-operative functional mobility and strength.  
 
A limiting factor in physical rehabilitation is a patient’s inability to activate the involved muscle 
groups postoperatively, a phenomenon termed Arthrogenic Muscle Inhibition (AMI) [1, 2]. AMI 
is a complex neurological process where the injury or surgery disrupts sensory and motor 
neurological pathways, resulting in decreased muscle activation and strength. AMI can be a 
major obstacle to a patient’s return to normal mobility and muscular function [2]. For example, 
patients who have undergone anterior cruciate ligament reconstruction (ACLR), may experience 
ineffective quadriceps activation and persistent hamstring contracture, leading to loss of passive 
and active range of motion (ROM). Even with standard physical therapy rehabilitation, patients 
with AMI have ineffective recovery due to decreased muscular activation and movement 
dysfunction [3].  
 
Visualization training with neurofeedback therapy is a non-invasive method that could be used 
with standard post-operative physical rehabilitation to decrease AMI and help patients recover 
pre-operative functional mobility and strength. 
 
The motor regions of the brain (motor cortex) play a crucial role in planning, controlling, and 
executing voluntary movements. The motor cortex is not only active during actual movement; 
mentally rehearsing motor acts without physically moving also activates the motor cortex [4]. 
For example, one could imagine themselves performing squats without squatting (visualization), 
this process activates the brain regions related to squatting. Such visualization training can 
enhance the brain’s ability to plan, control and execute movement without physical load on the 
body [5]. Theoretically, this training could help restore disrupted neurological pathways, leading 
to reduced AMI and improved patient recovery after surgery [6].  

 
When a brain region has heightened activity, passive sensors on the scalp can detect the 
increased electrical activity, this technique is known as electroencephalography (EEG). A 
computer can process the EEG signal and provide users with real time feedback on their 
concentration level and whether they are activating their motor cortex through mental 
visualization of movements (neurofeedback). This feedback process enhances the visualization 
training [6].  
 
This study aims to investigate the effect of visualization with neurofeedback on postoperative 
recovery in patients undergoing physical rehabilitation from 4 orthopedic surgical procedures: 
anterior cruciate ligament reconstruction (ACLR), total knee arthroplasty (TKA), total hip 
arthroplasty (THA), and hip arthroscopy (HA) for femoroacetabular impingement syndrome 
(FAIS). More specifically, neurofeedback training will be implemented using a novel technology 
developed by iBrainTech™ (Figure 1).  
 
The findings of this study have the potential to revolutionize physical rehabilitation protocols for 
patients, offering a novel approach that integrates visualization therapy with neurofeedback to 
enhance standard physical rehabilitation. This could lead to faster, more complete recoveries, 
and potentially mitigate the long-term impacts of AMI. The successful application of this 
technology would also help deepen current understanding of neuroplasticity, specifically the 
malleability of the neuromuscular pathways and how this can improve motor control. 
 
 
Figure 1 : The EEG device used in this study. 

 
 
Purpose 
 
The purpose of this study is to investigate the effect of visualization training with neurofeedback 
on postoperative recovery in patients rehabilitating from orthopedic surgeries. 
 
Hypothesis 
 
We hypothesize that through targeted visualization training with neurofeedback using 
iBrainTech™, post-surgical participants will experience improved muscle activation, which in 
turn will contribute to better rehabilitation outcomes, strength, such as range of motion, , and 
functional mobility. We also hypothesize that these improvements seen throughout the recovery 
period will have a positive impact on short-term patient-reported outcome surveys (PROs). 
 
3. Methods 
 
Trial Design 
 
This study is a randomized, blinded (outcome assessors, physicians and statisticians) controlled 
trial investigating the effect of neurofeedback visualization training on AMI in patients following 
orthopedic procedures. The study will have two arms – a 1:1 allocation ratio for the control 
group and for the intervention cohort – stratified into four orthopedic surgeries:  
o Anterior Cruciate Ligament Reconstruction (ACLR)  
o Total Knee Arthroplasty (TKA)  
o Total Hip Arthroplasty (THA)  
o Hip Arthroscopy (HA) for Femoroacetabular Impingement Syndrome (FAIS)  
 
There will be 30 participants per cohort arm for each procedure, totaling 240 participants for the 
project. In the event of any changes, modifications to eligibility criteria or study methods will be 
documented and justified in study amendments. In addition, any changes to data collection, 
analysis, or participant follow-up will be noted in trial records.  
 
Participants 
- 
Inclusion Criteria: 
o Patient age >18 years  
o Ability to complete neurofeedback training and follow study follow-ups  
o Indicated for one of the four investigated orthopedic procedures 
- 
Exclusion Criteria: 
o Inability to participate in neurofeedback training  
o Lack of decisional capability  
o History of stroke, movement disorder (e.g. Parkinson’s), peripheral neuropathy  
o Cardiac pacemaker or other internal electronic device  
o BMI >35  

o Previous surgery or specific pathology on the affected joint (refer to procedure 
specific indications below)  
 
Procedure Specifics:  
Anterior cruciate ligament reconstruction (ACLR) 
Procedure-specific Inclusion Criteria 
• Patients undergoing primary ACLR with autograft or allograft tissue 
• Adjunct lateral Extra-articular tenodesis will be included 
• Additional meniscus debridement and repair will be included 
Procedure-specific exclusion criteria 
• Revision ACL surgery 
• Moderate to Severe arthritis – Kellgren-Lawerence (KL) Grade > 3 
• Patients with meniscus root repair 
• Non-weight-bearing status exceeding 1 week postoperatively 
  
Total knee arthroplasty (TKA) 
Procedure specific inclusion criteria 
• Patients undergoing primary TKA 
• Preoperative total knee range of motion of at least 100 degrees (combined flexion and 
extension)  
• Prior extensor mechanism tendon repair, quadriceps or patella tendon. 
Procedure specific exclusion criteria 
• Revision surgery 
• Hinged implant 
• Any open procedure involving the knee joint  
• Symptomatic arthritis in the contralateral knee with planned or expected total knee 
arthroplasty within 6 months 
• Inflammatory Arthritis 
  
Total hip arthroplasty (THA) 
Procedure Specific Inclusion Criteria 
• Patients undergoing primary THA 
Procedure Specific Exclusion Criteria 
• Revision Surgery 
• Any open procedure involving the hip joint  
• Bilateral THA procedures 
• Inflammatory Arthritis  
  
Hip arthroscopy (HA) for femoroacetabular impingement syndrome (FAIS) 
Procedure Specific Inclusion Criteria 
• Patients undergoing HA for FAIS 
Procedure Specific Exclusion Criteria 
• Revision Surgery 
• Diagnosis of hip dysplasia 

 
Settings & Locations  
 
Conducted at Rush University Medical Center, specifically within:  
- 
The main campus of Midwest Orthopaedics at Rush (MOR) Sofija and Jorge O. Galante 
Orthopedic Building, 1611 W Harrison St, Chicago, IL 60612 
- 
Motion Laboratory in the MOR Orthopedic Building  
- 
Physical therapy facility (Chicago location)  
 
4. Interventions 
 
Control group: Standard post-surgical rehabilitation therapy  
Intervention Group: Standard post-surgical rehabilitation therapy + iBrainTech neurofeedback 
training  
- 
Procedure: Patients use EEG-based neurofeedback twice a week until 8 weeks post-
operatively. 
- 
Neurofeedback setup: EEG cap monitors motor cortex activation, guiding visualization 
exercises  
- 
Training sessions: Patients visualize movements, and EEG feedback helps optimize 
motor activation  
- 
 
Physical Therapy 
 
Patients will follow a standard physical therapy protocol. The protocol will be assigned by their 
respective surgeon who conducted the procedure and will be specific to the procedure that the 
patient underwent. The standardized physical therapy protocols will be attached in supplemental 
materials.  
 
Treatment Group Intervention:  
 
The main study intervention for the treatment group involves visualization training using the i-
BrainTech™ Platform.  
 
This is a technology that uses electroencephalography (EEG) to read the electrical activities in 
the brain [7]. Active neurons in the brain causes change in electrical activities on the scalp, 
detectable by electrodes placed on the scalp. The sensing electrodes are completely passive, 
incapable of sending electrical current to the wearer. An EEG cap will be used with sensing 
electrodes aligned to the frontal cortex and the motor cortex. The detected electrical activity from 
these locations of the scalp will transmitted to the computer, which allows for assessment of 
focus and motor cortex activity [8]. There are multiple cap sizes of the cap to ensure a 
comfortable fit. 
 
By concentrating and imagining themselves performing the rehabilitation movements 
(visualization), patients activate their own motor and pre-frontal cortices. The EEG sensors 
detects the increased brain electrical activity, and the iBrainTech™ software translates the EEG 

signal into a virtual avatar figure performing such movements on a computer monitor, providing 
feedback to the patients on their visualization efforts (neurofeedback)( Figure 2). Patients will 
effectively play a video game using their own brain signals. By turning this feedback process 
into a video game, the iBrainTech™ platform provides an incentive for the user to intensely 
focus and visualize the rehabilitation exercises, and in the process activate and strengthen the 
neural pathways responsible for these rehabilitation movements. The repeated activation of 
neural pathways theoretically improves their muscle control and reduces AMI [6]. 
 
 
Figure 2: Rendition of neurofeedback training process. Source: iBrainTech™ 
 
 
Instruction to Participants (how to play the “game”) 
 
The i-BrainTech™ training station has a laptop and EEG caps. Participants will be seated in 
front of the laptop and put on the appropriately sized EEG cap.  A conductive gel is injected into 
2 insertion points on the cap.  The column of gel touches the participant's skin on one side and 
the sensor on the other.  The gel is water-soluble and dries up in chunks and is not sticky. The 
conductive gel is routinely used in the clinic and pre-operative area for ultrasound. The 
wet gel can be wiped off with a paper towel and the dried gel can be pulled off the participant’s 
scalp as it does not stick to hair.  The remaining fragments will be washed away when the patient 
showers. 
 
The session will be started and the i-BrainTech™ software will provide on screen prompts and 
feedback to the user. 
 
First is a 2-minute calibration period. During this time, the user is prompted to relax their mind 
so baseline brain activity may be detected. The brain activity above the baseline is used to 
control the cartoon avatar performing rehabilitation exercises.  
 

After calibration, a 20-minute visualization training with neurofeedback session begins. 
Participants are prompted to imagine themselves performing various rehabilitation exercises 
(visualization). The selections of exercises are the rehabilitation exercises they will eventually 
perform at a physical therapy session, specific to their surgical procedures (Table 1).  The 
software provides real time feedback on how concentrated the user is with the task, and how well 
the user is at visualizing the specific therapy exercises. The video game incentivizes participants 
to concentrate on the visualization therapy to maximize their score.  
 
When the participant finishes the i-BrainTech™ training session, they will remove the EEG cap 
and move on to their standard of care physical therapy session. 
 
Table 1: Exercises performed during the sessions of visualization training with 
neurofeedback. 
Day 1 to 3 weeks 
3 weeks to 6 weeks 
6 weeks to 8 weeks 
Mini-Squats 
Mini-Squats w/DB 
Squats w/DB 
Air Squats 
Lateral lunge (involved) 
Lunges/DB (uninvolved) 
Lateral Lunge 
(involved) 
Lunges w/DB (involved) 
Reverse Lunge w/DB 
(involved) 
Gastroc Stretch  
(uninvolved) 
Reverse Lunges (involved) 
Lunges/DB (involved) 
Heel raises 
Lunges w/DB (uninvolved) 
Reverse Lunge w/DB 
(uninvolved) 
Leg Raise (involved) 
Heel Raises w/DB 
SL Stance 
Lunges (involved) 
Air Squats 
Heel Raises w/DB 
Lunges (uninvolved) 
Lateral lunge (uninvolved) 
Lateral lunge (involved) 
DB: Dumbbell. SL: 
Single leg 
 
5. FDA Status of the Device 
 
The i-BrainTech™ platform is approved by the Food and Drug Administration (FDA) as a Class 
II medical device. 
 
Participant Flow 

 
Figure 3: Participants Flow 
 
6. Clinic Flow and Timing of Assessments 
 
Participants in the intervention group will perform virtual rehabilitation exercises for 20 minutes 
2 times per week for the first 8 weeks postoperatively.  
 
Approximately 45 minutes total is required for setup, calibration, virtual rehabilitation, and clean 
up.  
 
After the virtual rehab session, patients in the intervention group will move on to their standard-
of-care PT session based on the surgeon’s protocol specific to their operation. Patients in the 
control group go directly to their standard PT session.   
 

The intervention group will spend an additional 45 minutes in clinic to perform the i-
BrainTech™ training session for a total study visit time of no more than 1-1.5 hours. 
 
The control group will spend 45 minutes to 1 hour of total study visit time. 
 
Participants will continue receiving their standard clinical care with their attending healthcare 
team throughout the study. In addition, they will attend scheduled study visits at the Motion 
Laboratory in the Orthopedic Building at Rush University Medical Center for motion analysis 
and physical testing at 2 months, 4 months, and 6 months post-surgery. 
At each visit, anthropometric data (age, height, weight, and BMI) will be collected first. 
Participants will then change into standardized clothing provided by the research team. 
 
Surface Electromyography (sEMG)  
 
sEMG data will be collected from five muscles: rectus femoris, vastus medialis oblique, vastus 
lateralis, semitendinosus, and biceps femoris, using a research-grade sEMG system. Electrode 
placement will follow the SENIAM (Surface EMG for a Non-Invasive Assessment of Muscles) 
protocol. 
 
Per SENIAM guidelines, the skin will be shaved, lightly abraded with abrasion wipes, and 
cleaned with alcohol wipes before electrode application. Electrodes will be placed at least 2 cm 
apart to minimize crosstalk, and voluntary contractions will be performed to confirm correct 
placement. 
 
Each muscle will be assessed individually before data collection. Once all sensors are verified, 
simultaneous sEMG and 3D kinematic data collection will be performed using Qualisys Track 
Manager software or similar. 
 
Motion Capture 
 
To evaluate patient-specific movement mechanics, a markerless multi-camera motion analysis 
system will be used to track kinematics, while instrumented force plates will measure ground 
reaction forces. The markerless system allows for accurate motion tracking while significantly 
reducing setup time—by up to 80% since no physical markers need to be placed on the skin 
 
Participants will be evaluated while completing the following functional tasks (Table 2). 
 
Table 2: Motion Capture and Strength Tests 
Timeline 
ACL 
TKA 
THA 
Hip Arthroscopy 

2 
months 
Motion Analysis 
Walk 
Bilateral Squats 
Forward Lunge 
 
 
Strength 
Knee Extension 
Motion Analysis 
Walk 
Bilateral Squats 
Forward Lunge 
 
 
Strength 
Knee Extension 
Motion Analysis 
Walk 
Bilateral Squats 
Forward and 
Lateral Lunge 
 
Strength 
Hip Extension 
Hip Abduction 
 
Motion Analysis 
Walk 
Bilateral Squats 
Forward and Lateral 
Lunge 
 
Strength 
Hip Extension 
Hip Abduction 
4 months 
Motion Analysis 
Walk 
Bilateral Squats 
Forward Lunge 
Single Leg Vertical 
Jump 
 
 
Strength 
Knee Extension 
Knee Flexion 
Motion Analysis 
Walk 
Bilateral Squats 
Forward Lunge 
Single Leg Vertical 
Jump 
 
 
Strength 
Knee Extension 
Knee Flexion 
Motion Analysis 
Walk 
Bilateral Squats 
Forward and 
Lateral Lunge 
Single Leg 
Vertical Jump 
 
Strength 
Hip Extension 
Hip Abduction 
Motion Analysis 
Walk 
Bilateral Squats 
Forward and Lateral 
Lunge 
Single Leg Vertical 
Jump 
 
Strength 
Hip Extension 
Hip Abduction 
9 months 
Similar to 4 months 
Similar to 4 months 
Similar to 4 
months 
Similar to 4 months 
ACLR: Anterior Cruciate Ligament Reconstruction; TKA: Total Knee Arthroplasty; THA: Total 
Hip Arthroplasty. 
 
    
 
At 2 months postoperatively, all patients—regardless of the surgical procedure—will undergo 
motion analysis and strength testing. The motion analysis will include walking, bilateral squats, 
and a procedure-specific lunge (forward lunge for ACLR and TKA; lateral lunge for THA and 
hip arthroscopy). Strength assessments will focus on knee extension for ACLR and TKA, and 
hip extension and abduction for THA and hip arthroscopy. 
 
At 4 months postoperatively, all groups will repeat the same motion analysis tasks as at 2 
months, with the addition of a single-leg vertical jump. Strength testing will now include two 
joint actions: knee extension and flexion for ACLR and TKA, and hip extension and abduction 
for THA and hip arthroscopy. 
 
At 9 months postoperatively, assessments will mirror those conducted at the 4-month follow-up 
for all surgical groups, including the same motion tasks and strength tests. 
 
This schedule allows for tracking recovery progression over time using both movement quality 
and strength performance. 
 
Strength testing 
 

Strength testing will be conducted after sEMG placement and motion analysis. Participants will 
keep the sEMG sensors on while performing maximum voluntary contractions (MVC) for knee 
flexion and extension. 
 
Isometric and isokinetic strength will be assessed using either a Biodex dynamometer or a 
handheld dynamometer, depending on equipment availability and participant-specific 
considerations. Strength data will also be used to normalize sEMG signals, with mean 
amplitudes of each phase expressed as a percentage of MVC. A 30% MVC normalization will be 
applied to allow for valid comparisons across groups. 
 
Total Testing Time 
 
The full testing session—including subject setup, EMG placement, motion analysis, and strength 
testing—will take approximately 30 to 45 minutes. Participants will be offered opportunities for 
water and seated rest breaks as needed throughout the session to ensure comfort and minimize 
fatigue. 
 
7. Outcomes 
 
Primary outcomes 
 
ACLR and TKA 
• Outcome Measure Title   
 Knee extension strength 
• Outcome Measure Description 
• Maximal isokinetic knee extensor strength (Newtons/BMI). Maximal isokinetic knee 
extensor strength will be assessed using standardized dynamometry procedures with 
Biodex Isokinetic Dynamometer (Biodex System 3) at 2, 4 and 6 months after surgery. 
Each participant will perform three to five maximal voluntary isometric contractions of 
the knee extensors. The average of the peak torque values will be used for analysis. To 
account for individual differences in body size, values will be normalized to the 
participant’s body mass index (Newtons/BMI). The first assessment will occur at 2 
months to ensure patient safety and measurement consistency, as early postoperative 
conditions (e.g., pain, swelling) could compromise the reliability and validity of strength 
testing. 
• Outcome Measure Time Frame 
 2, 4 and 6 months 
• Statistical Analysis 
 Linear mixed-effects models : 
o Linear mixed-effects models will be used to analyze changes in knee 
extensor strength between the intervention and control group across the 2-, 
4-, and 6-month follow-up assessments. This approach accounts for 
repeated measures within participants and allows for the evaluation of 
group differences over time. Group (intervention vs. control), time (2, 4 
and 6 months), and their interaction will be entered as fixed effects, with 

subject-level random intercepts. Significant main effects or interactions 
will be further examined using pairwise comparisons of estimated 
marginal means, with Tukey’s adjustment for multiple comparisons to 
determine pairwise differences. All results will be reported with estimated 
means, p-values, and 95% confidence intervals. . 
 
Hip arthroscopy and THA 
• Outcome Measure Title   
 Hip Abduction Strength 
• Outcome Measure Description 
 Maximal isokinetic hip abductor strength (Newtons/BMI). Maximal isokinetic hip 
abductor strength will be assessed using standardized dynamometry procedures 
with Biodex Isokinetic Dynamometer (Biodex System 3) at 2, 4 and 6 months 
after surgery. Each participant will perform three to five maximal voluntary 
isometric contractions of the hip abductors. The average of the peak torque values 
will be used for analysis. To account for individual differences in body size, 
values will be normalized to the participant’s body mass index (Newtons/BMI). 
The first assessment will occur at 2 months to ensure patient safety and 
measurement consistency, as early postoperative conditions (e.g., pain, swelling) 
could compromise the reliability and validity of strength testing.. 
• Outcome Measure Time Frame 
 2, 4 and 6 months 
• Statistical Analysis 
 Linear mixed-effects models : 
o Linear mixed-effects models will be used to analyze changes in hip 
abductor strength between the intervention and control group across the 
2-, 4-, and 6-month follow-up assessments. This approach accounts for 
repeated measures within participants and allows for the evaluation of 
group differences over time. Group (intervention vs. control), time (2, 4 
and 6 months), and their interaction will be entered as fixed effects, with 
subject-level random intercepts. Significant main effects or interactions 
will be further examined using pairwise comparisons of estimated 
marginal means, with Tukey’s adjustment for multiple comparisons to 
determine pairwise differences. All results will be reported with estimated 
means, p-values, and 95% confidence intervals. 
 
Table 3: Secondary outcomes 
Assessment 
Type 
Outcomes 
Statistical Analysis 
Timeframe 

Motion 
Analysis 
Walk 
Bilateral Squats 
Lunge 
Single Leg 
Vertical Jump 
  
Kinematics: 
Joint Angles: Hip, knee, 
ankle and trunk angles 
over the task cycle 
(waveforms: joint angle 
× % task cycle). 
Segment Orientations: 
Pelvis, thigh, shank, trunk 
and foot angles over the 
task cycle (waveforms: 
segment orientation × % 
task cycle). 
Angular 
velocities/Accelerations: 
Rate of change in joint 
angles during the task 
cycle. 
  
Kinetics 
Joint Moments: Hip, 
Knee and ankle external 
and internal moments in 
the three planes of motion 
(waveforms: joint moment 
× % task cycle). 
Ground Reaction Forces 
(GRFs): Vertical, medial-
lateral, anterior-posterior 
components over the task 
cycle (GRF x % task 
cycle). 
  
Spatiotemporal 
Parameters 
Stride Length, Step 
Length 
Cadence (Steps/Minute) 
Gait Speed 
Stance Time, Swing Time 
Double Support Time 
  
Muscle Activation 
(EMG) 
Statistical Parametric 
Mapping (SPM):  
Kinematics and Kinetics 
Differences between the 
intervention and control group 
across each task and at each 
timepoint. The outcome will 
be reported as statistically 
significant clusters (with 
associated p-values and 
confidence intervals - e.g. knee 
flexion angle at 75%–85% of 
the gait cycle), highlighting 
precise phases of gait where 
the intervention had effects. 
 
Linear Mixed-effects models:  
Spatiotemporal parameters 
and EMG: 
Differences between the 
intervention and control 
groups across each task and 
time point will be assessed 
using linear mixed-effects 
models. These models will 
include fixed effects for group 
(intervention vs. control), time 
(2, 4 and 6 months), and their 
interaction, with random 
intercepts for participants to 
account for repeated measures. 
This approach allows for the 
evaluation of both within-
group changes over time and 
between-group differences 
across visits: 
Significant main effects or 
interactions will be further 
examined using pairwise 
comparisons of estimated 
marginal means, with Tukey’s 
adjustment for multiple 
comparisons to determine 
pairwise differences. All 
results will be reported with 
2, 4 and 6 
months 

Key muscle groups 
(Vastus lateralis, rectus 
femoris, vastus medialis, 
semimembranosus, 
semitendinosus, gluteus 
maximus, and medius).  
Timing of Muscle 
Onset/Offset: Normalized 
mean and max amplitude 
EMG signals as a 
percentage of Maximum 
Voluntary Contraction 
(%MVC), averaged across 
trials. 
Co-contraction index to 
compare the quadriceps 
relative to the hamstrings 
Area under the curve 
(AUC) as a summary of 
the total activation during 
each task and its change 
over time  
 
estimated means, p-values, and 
95% confidence intervals. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
Strength 
Knee Extension 
Knee Flexion 
Hip Extension 
Hip Abduction 
  
Kinematics 
Angular Velocity 
 Maximal isokinetic and 
isometric strength 
(Newtons/BMI).  
Kinetics 
Peak Torque (raw and 
BMI normalized):  
Maximum hip and knee 
extension/flexion torque 
produced 
Torque Curve: The shape 
of the torque traces over 
the range of motion. 
 Work and Power: Total 
work done and power 
generated during 
extension/flexion and 
abduction. 
 
Differences between the 
intervention and control 
groups across each task and 
time point will be assessed 
using linear mixed-effects 
models. These models will 
include fixed effects for group 
(intervention vs. control), time 
(2, 4 and 6 months), and their 
interaction, with random 
intercepts for participants to 
account for repeated measures. 
This approach allows for the 
evaluation of both within-
group changes over time and 
between-group differences 
across visits. Significant main 
effects or interactions will be 
further examined using 
pairwise comparisons of 
estimated marginal means, 
 
2, 4 and 6 
months 

  
Muscle Activation 
(EMG) 
Key muscle groups 
(Vastus lateralis, rectus 
femoris, vastus medialis, 
semimembranosus, 
semitendinosus, gluteus 
maximus, and medius).  
Timing of Muscle 
Onset/Offset: Normalized 
mean and max amplitude 
EMG signals as a 
percentage of Maximum 
Voluntary Contraction 
(%MVC), averaged across 
trials. 
Co-contraction index to 
compare the quadriceps 
relative to the hamstrings 
Area under the curve 
(AUC) as a summary of 
the total activation during 
each task and its change 
over each visit  
 
with Tukey’s adjustment for 
multiple comparisons to 
determine pairwise 
differences. All results will be 
reported with estimated means, 
p-values, and 95% confidence 
intervals. 
Flexibility 
TKA and ACLR: 
Passive knee flexion 
ROM (o) 
Passive knee extension 
ROM (o) 
THA and HA: 
Thomas test (o) 
Passive internal/external 
rotation (o) 
Differences between the 
intervention and control 
groups across each task and 
time point will be assessed 
using linear mixed-effects 
models. These models will 
include fixed effects for group 
(intervention vs. control), time 
(2, 4 and 6 months), and their 
interaction, with random 
intercepts for participants to 
account for repeated measures. 
This approach allows for the 
evaluation of both within-
group changes over time and 
between-group differences 
across visits. Significant main 
effects or interactions will be 
further analyzed using post 
2, 4, and 6 
months 

hoc comparisons and Tukey’s 
adjustment to determine 
pairwise differences. Results 
will be reported with means, p-
values, and 95% confidence 
intervals. 
Patient- 
reported 
outcome 
measures 
(PROs) 
ACLR: 
International Knee 
Documentations 
Committee (IKDC) 
Questionnaire 
Knee Injury and 
Osteoarthritis Outcome 
Score for Joint 
Replacement (KOOS Jr) 
(Veterans RAND 12-Item 
Health Survey) VR12  
Patient-Reported Outcome 
Measurement Information 
System-Pain Interference 
(PROMIS-PI) 
PROMIS Physical 
Function (PROMIS-PF) 
PROMIS depression short 
form 
Anterior Cruciate 
Ligament-Return to Sport 
after Injury (ACL-RSI) 
Tampa Scale of 
Kinesiophobia (TSK-11) 
  
TKA: 
VR12 
KOOS Jr 
Knee Society Score 
Knee Single Assessment 
Numeric Evaluation 
(SANE) 
Differences between the 
intervention and control 
groups across each task and 
time point will be assessed 
using linear mixed-effects 
models. These models will 
include fixed effects for group 
(intervention vs. control), time 
(pre-op, 2, 4 and 6 months), 
and their interaction, with 
random intercepts for 
participants to account for 
repeated measures. This 
approach allows for the 
evaluation of both within-
group changes over time and 
between-group differences 
across visits. Significant main 
effects or interactions will be 
further analyzed using post 
hoc comparisons and Tukey’s 
adjustment to determine 
pairwise differences. Results 
will be reported with means, p-
values, and 95% confidence 
intervals.. 
Pre-op, 2, 4 and 
6 months, 1 
year, 2 years 

Joint Score 
EQ5D-3L 
Tampa Scale of 
Kinesiophobia (TSK-11) 
 
  
THA: 
VR12 
Hip Dysfunction and 
Osteoarthritis Outcome 
Score for Joint 
Replacement (HOOS Jr) 
Harris Hip Score 
Joint Score 
EQ5D-3L 
Tampa Scale of 
Kinesiophobia (TSK-11) 
 
HA 
PROMIS-PF 
PROMIS-PI 
12-item international Hip 
Outcome Tool (iHOT12) 
Hip Outcome Score-
Activities of Daily Living 
(HOS-ADL) 
HOS-Sports Subscale 
(HOS-SS) 
Tampa Scale of 
Kinesiophobia (TSK-11) 
Knee AMI 
Classification 
Sonnery-Cottet et al. knee 
AMI classification (Grade 
0-3) 
Differences in the distribution 
of knee AMI classification 
(grades 0–3, per Sonnery-
Cottet et al.) between groups 
will be assessed using Fisher’s 
exact test. 
2, 4, and 6 
months 

Digital Avatar 
Performance 
Metrics  
Performance metrics 
generated during the 
neurofeedback training 
sessions will be collected 
directly from the 
iBrainTech software:  
Attention, motor imagery, 
and session scores 
Differences between the 
intervention and control 
groups across each task and 
time point will be assessed 
using linear mixed-effects 
models. These models will 
include fixed effects for group 
(intervention vs. control), time 
(pre-op, 2, 4 and 6 months), 
and their interaction, with 
random intercepts for 
participants to account for 
repeated measures. This 
approach allows for the 
evaluation of both within-
group changes over time and 
between-group differences 
across visits.. Significant main 
effects or interactions will be 
further analyzed using post 
hoc comparisons and Tukey’s 
adjustment to determine 
pairwise differences. Results 
will be reported with means, p-
values, and 95% confidence 
intervals 
2, 4, and 6 
months 
Notes: ACLR: Anterior Cruciate Ligament Reconstruction; ACL-RSI: Anterior Cruciate 
Ligament – Return to Sport after Injury; AMI: Arthrogenic Muscle Inhibition; ANOVA: Analysis 
of Variance; AUC: Area Under the Curve; BMI: Body Mass Index; CI: Confidence Interval; 
EMG: Electromyography; EQ5D-3L: EuroQol 5 Dimensions – 3 Level version; GRF: Ground 
Reaction Force; HA: Hip Arthroscopy; HKA: Hip-Knee-Ankle; HOOS Jr: Hip Disability and 
Osteoarthritis Outcome Score for Joint Replacement; HOS-ADL: Hip Outcome Score – 
Activities of Daily Living; HOS-SS: Hip Outcome Score – Sports Subscale; iHOT12: 
International Hip Outcome Tool – 12-item version; IKDC: International Knee Documentation 
Committee; KOOS Jr: Knee Injury and Osteoarthritis Outcome Score for Joint Replacement; 
MVC: Maximum Voluntary Contraction; N: Sample Size; PROMIS-PF: Patient-Reported 
Outcomes Measurement Information System – Physical Function; PROMIS-PI: Patient-
Reported Outcomes Measurement Information System – Pain Interference; PROs: Patient-
Reported Outcome Measures; ROM: Range of Motion; SANE: Single Assessment Numeric 
Evaluation; SD: Standard Deviation; SPM: Statistical Parametric Mapping; THA: Total Hip 
Arthroplasty; TKA: Total Knee Arthroplasty; TSK-11: Tampa Scale of Kinesiophobia – 11-item 
version; VR12: Veterans RAND 12-Item Health Survey; %MVC: Percentage of Maximum 
Voluntary Contraction. 
 
8. Statistical Methods 
 

Statistical methods are summarized in Table 3. For the primary outcome, linear mixed-effects 
models will be used to assess changes in knee and hip strength following ACLR, TKA, THA, 
and HA procedures. Strength outcomes will be compared between the intervention and control 
groups at 2, 4, and 6 months postoperatively. This modeling approach accounts for repeated 
measures within participants and allows for the evaluation of group differences over time. Group 
(intervention vs. control), time (2, 4 and 6 months), and their interaction will be entered as fixed 
effects, with subject-level random intercepts. Significant main effects or interactions will be 
further examined using pairwise comparisons of estimated marginal means, with Tukey’s 
adjustment for multiple comparisons to determine pairwise differences. All results will be 
reported with estimated means, p-values, and 95% confidence intervals 
 
Secondary outcomes will follow a similar analytic approach using linear mixed-effects models, 
accounting for repeated measures and assessing group-by-time interactions, with appropriate 
post hoc testing as needed.  
 
To assess the time-series data of kinematics and kinetics across different conditions and time 
points, Statistical Parametric Mapping (SPM) will be utilized. SPM is a robust analytical 
approach that allows for the statistical evaluation of entire waveforms, reducing the limitations of 
discrete-point analysis in biomechanical research. SPM maintains the temporal structure of the 
data and enables the identification of significant differences across the entire movement cycle, 
offering a more comprehensive understanding of biomechanical adaptations post-surgery. 
  
SPM will be applied to joint angle waveforms, ground reaction forces, and external moment 
profiles to compare surgical groups, timepoints, and control conditions. This approach will help 
detect subtle but functionally relevant alterations in movement patterns that may not be captured 
using traditional peak or mean value analyses. 
 
Kinematic and kinetic data will be collected bilaterally to examine compensatory strategies in the 
contralateral limb. EMG and strength only in the affect side. The integration of markerless 
motion capture, inverse dynamics, and SPM analysis will provide a detailed and objective 
assessment of post-surgical movement patterns. 
 
Differences in the distribution of knee AMI classification (grades 0–3, per Sonnery-Cottet et al.) 
between groups will be assessed using Fisher’s exact test. 
 
Statistical significance for all analyses will be set at an a priori α of 0.05.  All data analyses will 
be completed using R version 4.2.3 (R Core Team). 
 
Loss to Follow Up  
 
Data analysis will be conducted according to the intention-to-treat (ITT) principle. Patients who 
are lost to follow-up for any reason will be included in the primary analysis using the last 
observation carried forward (LOCF) method.  
 
9. Power Analysis 
 

Strength 
 
Separate power analyses were conducted for the knee surgery cohort (ACL and TKA) and the 
hip surgery cohort (HA and THA). 
 
Knee Surgery (ACL and TKA) 
 
 
The power analysis for the knee surgery group was based on data from a previous randomized 
controlled trial by Moukarzel et al. (Moukarzel et al., 2019), which evaluated the effects of 
motor imagery on quadriceps strength following total knee arthroplasty (TKA). The original 
study included 12 patients with unilateral TKA, assessed six months postoperatively (10 females, 
2 males). The primary outcome was quadriceps maximum voluntary isometric contraction 
(MVIC), measured using a hand-held dynamometer. This method is highly correlated with the 
Biodex system currently used in the present trial (R = 0.91; Martin et al., 2006). 
 
Statistical analysis was performed in R version 4.3.2 using the pwr package. The mean 
quadriceps MVIC reported was 20.58 N/BMI (SD = 1.85). Assuming a two-group parallel 
design (intervention vs. control) with 30 participants per group (total n = 60), the study is 
powered at 80% to detect a between-group difference of 1.31 N/BMI at a two-tailed α = 0.05 
(adjusted α = 0.025 to account for multiple comparisons). This corresponds to a minimum 
detectable difference (MDD) of 6.31% between groups. 
 
Hip Surgery (HA and THA) 
 
The power analysis for the hip surgery group was based on data from a retrospective study by 
Servant et al. (Servant et al., 2022), which evaluated hip abductor strength before and three 
months after hip arthroscopy for femoroacetabular impingement (FAI). The study included 29 
individuals (mean age 27.4 ± 7.5 years; 76% female). The primary outcome was hip abductor 
MVIC, also measured with a hand-held dynamometer. 
 
The reported mean abductor MVIC was 1.97 N/kg (SD = 0.42). A two-group parallel design with 
30 participants per group (n = 60 total) provides 80% power to detect a between-group difference 
of 0.31 N/kg at a two-tailed α = 0.05 (adjusted α = 0.025). This represents an MDD of 15.6%. 
 
To contextualize the clinical relevance of the estimated minimal detectable differences (MDDs), 
previously published values for minimal clinically important differences (MCIDs) were 
reviewed. For quadriceps MVIC, Oliveira et al. (2021) (Oliveira et al., 2021) reported an MCID 
of 26.9% in older adults with COPD, with improvements associated with enhanced performance 
in the six-minute walk test. In patients undergoing ACL reconstruction, a limb strength 
asymmetry of 10% is considered a clinically relevant threshold and a predictor of reinjury. For 
hip abductor strength, although there is no universally accepted MCID after hip surgery, many 
studies consider a relative difference of 10–15% to be clinically meaningful. These values serve 
as important clinical benchmarks and support the interpretation that the proposed sample size (n 
= 60 per pathology group) is adequate to detect both statistically and clinically relevant between-
group differences in strength outcomes. 

 
Kinematics 
 
A separate power analysis was conducted for the secondary kinematic outcomes to estimate the 
minimum detectable differences achievable with the current sample size and 80% statistical 
power. This analysis helps ensure that the study is adequately powered to detect changes that are 
not only statistically significant but also clinically meaningful.  
 
The power analysis was based on data from a previous investigation (Antognini et al., 2024) 
conducted in the same laboratory where the current study will take place, using identical 
equipment, camera setup, and software configuration parameters. Individuals assessed in study 
were 5 healthy males (mean age 26) and 5 females (mean age 28) (n=10). The primary variables 
of interest for the power analysis were the knee peak flexion angle (for the ACL and TKA study 
arms) and the hip peak extension angle (for the hip arthroscopy and THA study arms) during the 
gait cycle, measured using a markerless motion capture system (Theia 3D, Theia Markerless 
Inc., Kingston, ON). The statistical analysis was conducted using R version 4.3.2 (R Core Team, 
2023) and the pwr package (Champely, 2020). 
 
For the knee flexion angle, Antognini et al. reported a mean of 19° with a standard deviation 
(SD) of 7.68° (Antognini et al., 2024). Using these values, a two-group parallel design with 30 
participants per group (total n = 60) was powered at 80% to detect a between-group difference of 
at least 5.65° at a two-sided α = 0.05 (adjusted α = 0.025 for sidedness). Similarly, for hip 
extension angle (mean = 9.25°, SD = 5.11°), the same sample size and power would yield a 
minimum detectable difference of 3.76°. 
 
To contextualize the clinical relevance of the estimated minimal detectable differences (MDDs), 
previously published values for minimal clinically important differences (MCIDs) were 
reviewed. For knee flexion angle, Guzik et al. (Guzik et al., 2020) reported an MCID of 6.81 
degrees based on gait analysis of the unaffected limb in stroke patients. In a different clinical 
context, Kubo et al. (Kubo et al., 2021) identified an MCID of 5 degrees for passive range of 
motion following total knee arthroplasty, with improvements in flexion associated with better 
knee function and higher patient satisfaction. Regarding hip extension angle, Guzik et al. (Guzik 
et al., 2021) established an MCID of 2.86 degrees in stroke patients using motion analysis of the 
unaffected limb. These values serve as clinical benchmarks to interpret the statistical power and 
meaningfulness of the differences targeted in this study. 
 
10. 
Randomization 
 
Sequence Generation 
 
Randomized list generation before trial commencement utilizing the National Institute of Health 
(NIH) Clinical Trial Randomization Tool. We will utilize a 1:1 allocation (intervention vs. 
Control) per procedure. 
 

The randomization sequence will be generated before trial commencement by an independent 
data manager using the Clinical Trial Randomization Tool developed by the National Cancer 
Institute (NCI). The tool will use the Asymptotic Maximal procedure, a restricted randomization 
method that limits the imbalance between trial arms to a pre-specified Maximum Tolerated 
Imbalance (MTI) of 3. The randomization list will be created for a total of 70 participants, with 
no stratification applied. 
 
Type of Randomization 
 
A simple two-arm parallel group design will be used with a 1:1 allocation ratio for each 
procedure (ACLR, THA, TKA, and HA), with a separate randomization list of 35 participants 
per group (total n=70) generated independently for each procedure. Each procedure will be 
treated as a distinct trial with its own allocation sequence. The final participants will be randomly 
assigned in accordance with the MTI threshold, allowing minor tolerable imbalances between 
arms. No stratification or blocking will be implemented. The increased sample size per group 
(n=35 instead of n=30) accounts for potential losses or allocation issues during the study. 
Additional allocation slots beyond the target sample size will be generated to account for 
unexpected exclusions, dropouts before randomization, or technical errors during allocation. 
 
Allocation Concealment Mechanism 
 
Allocation concealment will be ensured using the REDCap (Research Electronic Data Capture) 
Randomization Module, which provides a secure, centralized, and automated platform for 
treatment allocation. The randomization sequence will be generated and implemented within 
REDCap by an independent data manager who will not be involved in participant enrollment, 
intervention, and outcome assessment. The system will be configured to assign participants in 
real time only after eligibility has been confirmed and baseline data have been entered, thereby 
preventing any foreknowledge of the upcoming assignment. Investigators, study staff, and 
participants will remain unaware of the allocation sequence prior to assignment (Figure 4). 
REDCap’s access controls and audit logs will safeguard against manipulation and preserve 
allocation concealment throughout the trial. 

 
Figure 4 Randomization and allocation concealment procedures 
 
 
Implementation 
 
All patients referred for ACLR, TKA, THA, or HA procedures in the physician’s office will be 
referred to the research team to assess eligibility criteria and initiate the enrollment process, 
either in person or by phone. Eligible patients will be enrolled in the study during the pre-
operative period and will complete baseline assessments. Following surgery, participants will be 
assigned to one of the intervention groups one day prior to the intervention date. Group 
allocation will be performed by an independent data manager using the REDCap Randomization 
Module and communicated only to the team responsible for delivering the NFVT. The individual 

responsible for generating the allocation sequence will be distinct from those involved in 
enrolling participants and assigning interventions.  
 
Blinding 
 
Investigators and physicians will be blinded to group allocation to minimize bias in clinical 
decision-making and post-operative care. Patients will not be blinded due to the nature of the 
neurofeedback intervention, which cannot be masked. Both study groups will receive standard 
rehabilitation, with the only difference being the addition of NFVT in the intervention arm. The 
neurofeedback sessions will take place within the physical therapy clinic, immediately prior to 
scheduled physical therapy appointments. 
 
The team delivering the neurofeedback intervention will be the only personnel aware of group 
allocation. Treating physicians, physical therapists, outcome assessors, and the statistical analysis 
team will remain blinded to participant allocation throughout the trial. Statistical analyses will be 
performed by the Rush Statistical Analysis team, an independent third-party ancillary resource, 
using a coded dataset to ensure blinding is maintained during data analysis. 
 
Unblinding Procedures 
 
Given the non-invasive nature of the EEG-based neurofeedback intervention, adverse effects are 
not expected. However, in rare cases where unblinding is required—such as equipment 
malfunction, unexpected clinical events, or participant withdrawal—a formal request must be 
submitted to the principal investigator (PI) or Data and Safety Monitoring Board (DSMB). All 
unblinding events will be logged with justification and date. 
 
For emergencies, a dedicated study coordinator will have secure access to the REDCap 
randomization module and group allocation. This coordinator will be available to authorized 
clinical staff in urgent scenarios requiring immediate unblinding. Outcome assessors and data 
analysts will remain blinded throughout the study. 
 
These procedures align with CONSORT guidelines and will be included in staff training to 
ensure adherence. 
 
11. 
Recruitment 
 
The investigators will identify eligible patients in the clinic, and the research study staff will 
discuss the study with eligible patients. The informed consent process may occur over a period of 
several discussions, culminating in the signing of a consent form in the office (iPad) or sent to 
their verified email address.  
  
Informed consent will be obtained via the eConsent process through the secured platform Patient 
IQ. The patient will be prompted to reply with the appropriate passcode to access the consent 
form and then provide the passcode again with their signature (secured). A copy of the time 
stamped document will be sent to the study team through the electronic platform and a copy will 

be sent to the participant. All participants will be consented prior to surgery and the performance 
of research related testing activities.   
 
12. 
Risks 
 
In any routine activities or exercise, there is an inherent risk of falling and musculoskeletal 
injuries. However, this risk will be minimized by using activities that are adequate for the 
training level of the subject. Subjects will only perform tasks that they are used to performing in 
their routines, and which they feel comfortable and confident to do. Furthermore, there will be 
staff supervision and close physical proximity to avoid falls and help in the execution of the task.  
 
Reassurance of the possibility of study abandonment without compromise of current medical 
treatment will be provided during all study visits.  
 
There are no alternative procedures, the only alternative to participation is not to participate. 
There are no additional risks for the participants than the ones that they are already exposed to 
during their normal training routines.  
 
There is a risk of breach of confidentiality for participation in this study. Measures will be taken 
to protect patient privacy. To minimize this risk, data will be stored on a password-protected 
secure Rush server using Microsoft 365 OneDrive. 
 
Side effects, risks, and/or discomforts from participation in this study may include fatigue during 
testing from the activities, minor skin irritation (i.e., reddening) from the adhesive used to place 
the sEMG sensors, discomfort in the limbs the following day due to the activities and potential 
minor muscle or joint soreness. 
 
The risk for performing visualization exercises with neurofeedback training is minimal and does 
not exceed the risk of performing physical therapy. 
 
13. 
Limitations 
 
While there is a great effort to produce highly reliable and generalizable results, there are 
limitations to this study that must be addressed. One potential source of bias is patient adherence 
to neurofeedback therapy, which may vary and influence treatment outcomes. The sample size, 
limited to 240 participants with 30 interventions per procedure type, may constrain the statistical 
power and affect the broader applicability/generalization of results. Additionally, the novelty of 
using EEG neurofeedback in the postoperative setting presents challenges for comparative 
analysis, as there is a lack of precedent in the existing literature. The clinical treatment, including 
the surgical procedure and physical therapy, will follow a pragmatic approach, allowing for 
natural variations in clinical practice across patients and providers. While this enhances the 
external validity and real-world applicability of the findings, it may introduce variability that 
could influence outcomes. 
 

Blinding poses another limitation; although physicians, researchers, and the data analysis team 
are masked to group allocation, participants are aware of their intervention, which could 
introduce potential expectation bias. Technological factors, such as EEG signal variability and 
the need for precise device calibration, may also affect the accuracy and consistency of data 
collection.  
 
14. 
Generalizability 
 
The generalizability of this study is inherently limited by its design. The population is restricted 
to orthopedic surgical patients, and the exclusion of individuals with a body mass index greater 
than 35, prior surgery on the affected joint, or underlying neurological disorders may further 
reduce external validity. As a single-center trial conducted at Rush University Medical Center, 
the findings may not be fully representative of broader or more diverse populations. Moreover, 
because the intervention relies heavily on patient engagement and adherence, its feasibility and 
effectiveness could differ across clinical settings. Differences in rehabilitation protocols across 
institutions may impact reproducibility and generalizability of the findings.  
 
15. 
Interpretation 
 
The results of this trial will be interpreted in the context of existing orthopedic rehabilitation 
literature, with a focus on balancing the potential benefits, such as enhanced neuroplasticity and 
AMI reduction, against risks related to adherence and technological constraints. If successful, 
this study may serve as a step toward integrating neurofeedback into postoperative rehabilitation 
protocols. Both patient-reported outcomes (e.g. PROMIS, KOOS Jr, IKDC) and objective 
measures (e.g. motion analysis, strength testing) will be used to evaluate the efficacy of the 
intervention.  
 
16. 
Other Information 
 
Funding 
 
An internal department fund will be utilized for the majority of the study funding. The Walbert 
Sports Medicine Endowed Education Fund is dedicated to supporting high-quality research 
studies. The study utilizes the NFVT and EEG caps, provided by iBrainTech for research 
purposes. Participants in the study will receive compensation for their involvement, including 
parking, and a total of $150 for completing all three study visits. The compensation is 
progressive, with participants receiving a $25 Visa gift card after the first visit, a $40 Visa gift 
card after the second visit, and an $85 Visa gift card after the third (final) visit. There is no cost 
to participants, as all study-related expenses, including neurofeedback therapy and testing, are 
covered by the Walbert Sports Medicine Endowed Education Fund and the Midwest 
Orthopaedics at Rush Research team. Results will be shared with participants as soon as the 
study is peer-reviewed and published. Our team will be able to address via e-mail any questions 
or concerns. 
 

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