A Determination of Efficacy and Therapeutic Benefits of Blood Flow Restriction Training in an Adolescent Population
Phase: NA
Conditions: Blood Flow Restriction, ACL Tear, ACL Injury
Sponsor: Connecticut Children's Medical Center

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A Determination of Efficacy and Therapeutic Benefits of Blood Floor Restriction Training in an Adolescent Population 
IRB# 19-168 
Clinical Trial# NCT04285879  
December 22, 2021 
PRINCIPAL INVESTIGATOR: Adam Weaver, PT, DPT  
 
 
 
DEPARTMENT: Sports Physical Therapy 
INSTITUTION: Connecticut Children’s 
PHONE: (860)284-0246 
EMAIL: aweaver@connecticutchildrens.org 
 
 
 
 
 
 
 
 
 
 
CO-INVESTIGATOR: Allison Crepeau, MD 
CO-INVESTIGATOR:  Dylan Roman, PT, DPT 
DEPARTMENT: Elite Sports Medicine 
DEPARTMENT:  Sports Physical Therapy  
INSTITUTION: Connecticut Children’s 
INSTITUTION:  Connecticut Children’s 
PHONE: (860) 837-9212 
PHONE: (860)284-0246 
Email: acrepeau@connecticutchildrens.org 
EMAIL: droman@connecticutchildrens.org 
 
 
CO-INVESTIGATOR: Art Fredericks, MS, PT 
CO-INVESTIGATOR: Nick Giampetruzzi, MS, PT  
DEPARTMENT:  Sports Physical Therapy 
DEPARTMENT: Sports Physical Therapy  
INSTITUTION: Connecticut Children’s 
INSTITUTION: Connecticut Children’s  
PHONE: (860)284-0246 
PHONE: (860)284-0246 
EMAIL: afredericks@connecticutchildrens.org 
EMAIL: ngiampetruzzi@connecticutchildrens.org 
 
 
CO-INVESTIGATOR: Adel Lolic, BS, MS 
CO-INVESTIGATOR: Jennifer Prue 
DEPARTMENT: Sports Physical Therapy 
DEPARTMENT:  Sports Physical Therapy 
INSTITUTION: Connecticut Children’s 
INSTITUTION: Connecticut Children’s 
 
PHONE: (860)284-0246 
PHONE: (860)284-0246 
EMAIL: alolic01@connecticutchildrens.org 
EMAIL: jprue@connecticutchildrens.org 
 
 
 
CO- INVESTIGATOR: Mike Rieger, CSCS 
 
DEPARTMENT: Sports Physical Therapy 
INSTITUTION: Connecticut Children’s 
PHONE: (860) 284-0246 
EMAIL: mrieger@connecticutchildrens.org 
 
 
 
STUDY COORDINATOR:  Adam Weaver, PT, DPT 
DEPARTMENT:  Sports Physical Therapy 
 
INSTITUTION:  Connecticut Children’s 
 
PHONE: (860)284-0246 
EMAIL: aweaver@connecticutchildrens.org 
 
 
 
 
 
 
 
 
 
 
 
 
 

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IS THIS A STUDENT OR TRAINEE PROJECT?       _x__ NO         ___ YES  
 
  
  
   
 
           
 
 
 
 
 
IF YES, INDICATE LEVEL: 
 
___ Medical/Dental Student 
 
 
 
 
 
 
___ Resident 
 
 
 
 
 
 
___ Fellow 
 
 
 
 
 
 
___ Undergraduate 
 
 
 
 
 
 
___ Other (specify ________________________)      
 
 
IF YES, HAS FACULTY ADVISOR REVIEWED THE PROTOCOL?      ___ NO       ___ YES 
                 
 
Note:  Student researchers are required to attend the Scientific Review Committee meeting when 
           their protocol is discussed.                                                                                                                                                            
 
 
 

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Contents 
 
Introduction  
Purpose of Research, Specific Aims and Hypotheses 
Background  
Previous Work or Preliminary Studies 
Methods 
 
Target population 
 
Inclusion Criteria 
 
Exclusion Criteria 
 
Identification, recruitment, consent and retention of subjects  
 
Screening procedures 
Sample size justification 
Accrual and Expected Duration of Accrual 
Materials and Methods 
 
Setting 
 
Pre-testing 
 
Roles and responsibilities 
Administrative Organization 
Data Collection and Management 
Data Analysis 
Human Subjects Protection and Ethical Conduct of Study 
 
Risks and Benefits of Study 
Use of Study Results 
Budget 
Budget Justification 
Appendices 
 
 
References Cited 
 

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Introduction 
 
Anterior cruciate ligament (ACL) injury is a very common injury for adolescents and young adults with over 
200,000 ACL injuries reported in the United States each year [1].  The standard treatment for this injury 
includes ACL reconstruction surgery and physical therapy.  Rehabilitation of this surgery requires that adequate 
quadriceps rehabilitation is important for full return function and activity.  The role of quadriceps strength 
recovery after ACL reconstruction has been well studied and is associated with return to play times, knee 
kinematics and patient reported outcomes [2].  Paterno et al. reported that patients with greater fear on Tampa 
Scale of Kinesiophobia (TSK-11) were six times more likely to have a quadriceps LSI of less than 90% 
supporting the role of adequate quadriceps strength in reduction of risk of sustaining a contralateral ACL injury 
or re-injury [3]. Ithurburn additionally reported that athletes who demonstrated quadriceps strength asymmetry 
at time of return to sport (RTS) were likely to demonstrate lower knee related function [4].  
 
Background  
Exercise training with blood flow restriction (BFR) is a technique increasingly used in physical therapy and 
rehabilitation settings as an alternative to heavy load resistance exercise, and has increased in popularity in 
clinical and healthy populations over the last two decades.   Exercise is completed in conjunction with a surgical 
grade pneumatic cuff or tourniquet.  Evidence has suggested that BFR assists with muscle hypertrophy, as well 
lower extremity and upper extremity strength in several populations including athletes, post-operation 
rehabilitation [5], and the elderly [6]. The clinical value of this technique has been posed to allow increased 
muscle adaptation and hypertrophy under low loads and intensity that could heretofore only be accomplished 
with impact activities and more intense training protocols.  This is very attractive in a population of early post-
operative patients who are not able to engage in this level of activity.  
 
Following ACL reconstruction patients have demonstrated persistent quadriceps strength deficits during 
and after rehabilitation.  Despite there being special attention paid to restoring quadriceps and hamstring 
strength to pre-operative levels, there is a need for additional intervention. The utilization of BFR in conjunction 
with current rehabilitation standards of care has shown potential [7]. A meta-analysis completed in 2017 
comparing BFR training on musculoskeletal rehabilitation versus traditional low load training, and reported that 
low load BFR training to be more effective in helping patients regain strength than traditional low load strength 
training [7]. In a 2018 review of BFR during ACL rehabilitation the authors state the use of BFR as a safe 
alternative to heavy loads reducing the risk of damage to the graft, cartilage, and meniscus [8]. Current ACSM 
guidelines for resistance training recommend 70% of a single maximum repetition (RM) to elicit strength and 
hypertrophy adaptations [9].  BFR provides an alternative to heavy load resistance training due to the light loads 
prescribed to help reduce mechanical stress on the post-operative knee. 
 
Connecticut Children’s Sports Physical Therapy and Elite Sports Medicine have a long relationship of 
working collectively with the management of patients with ACL tears both surgically and with rehabilitation 
post-surgically.  The current standard of care for the rehabilitation of ACL injuries includes several 
interventions and the process can last up to 12 months.  The early phases of rehabilitation include the use of 
therapeutic exercise, manual therapy and modalities to help reduce pain, normalize range of motion and gait.  In 
the later phases, a progressive lower extremity strengthening program is completed, in addition to plyometric 
and jump training.   Finally, Standardized strength assessments at 3 months’ post-operative, and return to sport 
test between 6 and 9 months are used to help physical therapists and surgeons in clinical decision making for 
progression with functional and recreational activities.  Since early 2019, BFR training has been implemented 
consistently for post-operative patients at Connecticut Children’s Sports Physical Therapy that have undergone 
ACL reconstruction, as well as patellar and shoulder stabilization procedures.    
 
While there are a number studies that have reported on the use of BFR in the adult population 
[14], there is limited information about the use of BFR in the adolescent population.  This study aims to 

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evaluate the use of BFR training in conjunction with traditional ACL reconstruction rehabilitation in 
adolescents.   
 
Previous Work 
 
Until recently, previous studies have examined the use of BFR with respect to muscular strength, 
endurance and hypertrophy.  With the rise in popularity of BFR, there has been increased attention to overall 
safety issues of training with BFR. The potential risks to the cardiovascular system that have been considered 
are increased blood pressure responses, thrombolytic events and damage to the vascular system [10].Despite 
these concerns, there have been several extensive reviews published demonstrating that the side effects are 
minimal [10, 11, 12], and that training with BFR and when compared with traditional methods shows no greater 
risk [13].   Additionally, a closer look at the literature has demonstrated that the use of BFR has shown 
significant strength adaptations in multiple patient populations: 
 
 A 2017 study showed a 2-fold improvement in extension and flexion strength with the use of 
BFR in patients after knee arthroscopy [15].  
 
 Patients with patellofemoral pain had greater improvements in knee extension strength following 
the use of BFR training [14]. 
 
 A 2003 study demonstrated improved quadriceps strength with BFR training in patients after 
ACL reconstruction [16].  
 
 
 Greater improvements in thigh circumference as opposed to a standard group [17]. 
 
Research Question: 
The purpose of this study is to evaluate the addition of BFR-based exercise to traditional methods of physical 
therapy.  Does the use of BFR-based exercise improve strength, hypertrophy, functional and patient reported 
outcomes after ACL Reconstruction in the adolescent population?   
Purpose of the Research, Specific Aims and Hypotheses 
 
The purpose of this study is to determine the safety and efficacy regarding the addition of BFR-based exercise 
to traditional methods of physical therapy in the adolescent, post-surgical population.   
 
Primary aims: 
 
1. To determine the relationship between adjunct BFR training during post-surgical rehabilitation and 
isometric and isokinetic lower extremity strength measures (HUMAC isokinetic dynamometer).  
a. We hypothesize that there will be a positive association between BFR training and isometric 
and isokinetic lower extremity strength  
2. To determine the impact of adding BFR training during post-surgical rehabilitation on functional 
outcomes. 
a. We hypothesize that BFR training will improve scores on lower extremity functional tests 
when compared to a control group.  

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Secondary aim: 
1. To determine the impact of adding BFR training during post-surgical rehabilitation on patient 
reported outcomes. 
a. We hypothesize that BFR training will show greater patient reported outcome scores on the 
post-op when compared to a control group.  
2. To determine the impact of adding BFR training during post-surgical rehabilitation on hypertrophy 
and mid-thigh circumference. 
a. We hypothesize that BFR training will demonstrate significant increased mid-thigh 
circumference over measured time points.  
3. To determine and record patient tolerance and reported side effects and to BFR training during post-
surgical rehabilitation. 
a. We hypothesize that patient tolerance to BFR will be consistent with previously published 
literature. 
Study Design 
The planned pilot study is a prospective study to compare the use of exercises augmented with BFR with 
quantitative measurements of strength and patient reported outcomes. A total of 33 youth and adolescent 
patients undergoing a surgical procedure for ACL reconstruction at Connecticut Children’s Elite Sports 
Medicine and completing physical therapy at Connecticut Children’s Sports Physical Therapy will be recruited 
for this study. Additionally, 14 patients will be recruited that do not participate at Connecticut Children’s Sports 
Physical Therapy and do not receive BFR training as prospective controls.  Should we be unable to obtain 20 
prospective controls, a review of data from 20 previous patients, matched for age, sex, BMI and surgical 
procedure that completed physical therapy at Connecticut Children’s Sports Physical Therapy will be used as a 
comparison.    
Target Population 
The target population for this study consists of patients post ACL Reconstruction whom have been 
treated and followed by Elite Sports Medicine at Connecticut Children’s and completed physical therapy at 
Connecticut Children’s Sports Physical Therapy.  The inclusion and exclusion criteria will be the same for both 
the study and control groups.   
Study Group Inclusion criteria: 
 
Patients between the age of 12 and 18 years at the time of surgery. 
 
Post–primary ACL reconstruction  
 
Orthopaedic surgical intervention (including all additional procedures at the knee) completed by 
one of the Elite Sports Medicine physicians. 
 
Patient completed postoperative rehabilitation following standard protocols  
 
No contraindications to performing BFR, as outlined in the Owens Recovery [18] Science 2018 
Personal Blood Flow Restriction manual.  

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Prospective Control Inclusion Criteria: 
 
Patients between the age of 12 and 18 years at the time of surgery. 
 
Post–primary ACL reconstruction  
 
Orthopaedic surgical intervention (including all additional procedures at the knee) completed by 
one of the Elite Sports Medicine physicians. 
 
Patient completed postoperative rehabilitation following standard protocols  
 
Patient did NOT use BFR training during their rehabilitation 
 
Patient did NOT complete physical therapy at Connecticut Children’s Sports Physical Therapy. 
Exclusion criteria for study group and prospective controls:  
a. Specific exclusions 
 
Patients older than 18 and younger than 12 at the time of surgery 
 
Any additional diagnoses or deformity not related to knee injury that could affect knee strength 
 
Additional lower extremity injury at time of knee injury (e.g., ankle injury) requiring treatment 
Previous surgical intervention on the knee (ipsilateral and contralateral) 
Patients with weight bearing restrictions for greater than two weeks after surgery due to concomitant pathology 
such as meniscal root/radial repair, chondral pathology, or multi-ligament pathology. Generic exclusion: 
“Subjects not meeting all inclusion criteria.” 
The exclusion of age is to ensure that the study population is old enough to complete testing on the HUMAC 
isokinetic dynamometer and young enough to be treated by one of our Elite Sports Medicine physicians. 
The secondary diagnosis and previous knee injury exclusions are to limit the influence of other diagnoses or 
injuries on measured knee strength, as well as provide a more homogeneous group for comparison to past data.  
Identification, recruitment, consent and retention of subjects  
 
Patient Screening and Determination of Eligibility 
 
Pre-Screening 
All potential patients undergoing ACL reconstruction at Elite Sports Medicine will be approached for 
participation for this study.  Patients scheduled to undergo ACL reconstruction will be screened by the 
individuals listed on this protocol using our pre-screening documentation form.  All patients undergoing ACL 
reconstruction undergo a pre-operative appointment.   
 
Identification and Recruitment:  
Once identified as a potential candidate, the study purpose and protocol will be explained and a brief summary 
of the study will be provided at the conclusion of the pre-operative appointment.  Patients must meet all the 
requirements of inclusion and exclusion criteria to be eligible for consent. 
 
 
 
 

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Consent:  Consent will take place at the pre-operative visit.  The patient/parent will be given a detailed 
description of the purpose and methodology for this study.  They will have the opportunity to read the consent 
forms and ask any questions they may have about the research.  If they agree to participate, they will be asked 
to sign the consent form and a copy will be provided.  
 
If patients agree to enroll, all demographics and information listed in the protocol will be stored in a data 
collection sheet that is listed in the attachments.  This sheet will be used to record all pertinent information for 
all active participants on the study and stored in a secure folder on the G drive.   
.  
 
Retention:  Eligible patients will be required to be seen for a minimum of 90% of patient visits to be included in 
this study.  
 
Retrospective control: Patients that will be used as part of the retrospective control will be collected using a 
billing run with CPT codes related to ACL reconstruction from January 2017- January 2019. 
 
Patient Reported Outcomes:     
1) 4 Patient reported outcome measures will be collected at 5 time points listed below:  
 
 
a) Pre-operative visit  
 
 
b) 3 months post-operative 
 
 
c) Return to sport testing 
 
 
d) 12 month follow up 
 
 
e) 2 year follow-up over phone or email 
 
2) Outcome measures completed: 
 
 
a) International Knee Documentation Committee (IKDC) 
 
 
b) Anterior Cruciate Return to Sport after Injury (ACL-RSI) 
 
 
c) Knee Injury and Osteoarthritis Outcome Score (KOOS) 
 
 
d) Marx Activity Rating Scale (MARX) 
Functional Outcome Definitions/Data Points Collected 
1. Demographic information will be collected and outcome measures will include the following: 
 
a. Age 
b. Medical record number 
c. Date of ACL surgery and related surgeries 
d. Sex 
e. Graft Type 
f. Surgeon 
g. Sport 
h. Level of competition in sport 
i. Weight and Height 
j. BMI 
k. Weight bearing precautions (weeks) 
l. Limb length (cm): ASIS to superior medial malleolus 
m. Tegner Scale 
2. Opened or closed Physis  (or skeletal maturity)  

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3. Data will be collected at five different time points during the rehabilitation process.  The current 
standard of care includes a pre-operative visit, a 3-month assessment visit, and a return to sport visit 
between 6-9 months post-operative, and a1 year follow up. Additionally, we will collect data a 2 year 
phone/email follow up to record patient outcomes.  These assessments are completed in conjunction 
with the surgeon’s follow up visit.  The physical therapist completing the assessment will record the 
outcomes in a secure Excel data collection form.(or Access data base)  
4.  
A) Pre-operative visit 
 
a. Isometric knee extension at 60 degrees on involved and involved side.  
i. Quadriceps deficit= 100- (Knee extension peak torque involved/knee extension peak 
torque uninvolved) 
b. Isometric knee flexion at 60 degrees on involved and uninvolved side 
i. Hamstring Deficit= 100- (Knee flexion peak torque involved/knee flexion peak torque 
uninvolved) 
c. Isometric hip extension at 60 degrees on involved and uninvolved side 
i. Hip extension deficit= 100- (Hip extension peak torque involved/hip extension peak 
torque uninvolved) 
d. Quad hypertrophy will be measured by thigh circumference measurement.  
i. Measured at 10cm above the superior pole of the patella bilaterally  
B) 3 month evaluation:  
e. Isometric knee extension at 60 degrees on involved and involved side.  
i. Quadriceps deficit= 100- (Knee extension peak torque involved/knee extension peak 
torque uninvolved) 
f. Isometric knee flexion at 60 degrees on involved and uninvolved side 
i. Hamstring Deficit= 100- (Knee flexion peak torque involved/knee flexion peak torque 
uninvolved) 
g. Isometric hip extension at 60 degrees on involved and uninvolved side 
i. Hip extension deficit= 100- (Hip extension peak torque involved/hip extension peak 
torque uninvolved) 
h. Quad hypertrophy will be measured by thigh circumference measurement.  
i. Measured at 10cm above the superior pole of the patella bilaterally. 

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i. Y Balance Test (all measures taken bilaterally) 
i. 3 trials anterior reach involved and uninvolved (cm) 
ii. 3 trials posteromedial reach involved and uninvolved (cm) 
iii. 3 trials posterolateral reach involved and uninvolved (cm) 
iv. Anterior reach difference= Max anterior reach involved – Max anterior reach uninvolved 
v. Posteromedial reach difference= Max posteromedial reach involved- Max posterior reach 
uninvolved 
vi. Posterolateral reach difference= Max posterolateral reach involved-Max posterolateral 
reach uninvolved. 
vii. Involved and Uninvolved Composite score= (Max anterior reach+ Max posteromedial 
reach + 
max posterolateral reach)/(3*Limb Length) *100. 
j. 8” Anterior Stepdown Test (measures taken bilaterally) 
i. Involved repetitions= Max repetitions in 1 minute. 
ii. Uninvolved repetitions= Max repetitions in 1 minute. 
k. Elevated single leg bridge test completed with a 12” box (all measures taken bilaterally) 
i. Involved repetitions= Max repetitions in 1 minute. 
ii. Uninvolved repetitions= Max repetitions in 1 minute. 
l. Half kneeling dorsiflexion distance (all measures taken bilaterally) 
i. Half kneeling difference = half kneeling involved- half kneeling non involved  
5. Return to sport testing:  
a. Isometric knee extension at 60 degrees on involved and involved side.  
i. Quadriceps deficit= 100- (Knee extension peak torque involved/knee extension peak 
torque uninvolved) 
b. Isometric knee flexion at 60 degrees on involved and uninvolved side 
i. Hamstring Deficit= 100- (Knee flexion peak torque involved/knee flexion peak torque 
uninvolved) 
c. Isokinetic knee extension at 300 deg/ sec, 180 deg/sec, and 60 deg/ sec 
i. Quadriceps deficit= 100- (Knee extension peak torque involved/knee extension peak 
torque uninvolved) 

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d. Isokinetic knee flexion 300 deg/ sec, 180 deg/sec, and 60 deg/ sec 
i. Hamstring Deficit= 100- (Knee flexion peak torque involved/knee flexion peak torque 
uninvolved) 
e. Isometric hip extension at 60 degrees on involved and uninvolved side  
i. Hip extension deficit = 100 – (hip extension peak torque involved/ hip extension peak 
torque uninvolved)  
f. Quad hypertrophy will be measured by thigh circumference measurement.  
i. Measured at 10cm above the superior pole of the patella bilaterally 
g. Anterior reach test (all measures taken bilaterally) 
i. 3 trials anterior reach involved and uninvolved (cm) 
ii. Anterior reach difference= Max anterior reach involved – Max anterior reach uninvolved 
h. Single leg heel raise testing (all measures taken bilaterally) 
i. Maximum number of repetitions completed to maximum height at pace of 60 beats per 
second 
ii. Heel raise difference = heel raise involved – heel raise non involved  
i. 8” Anterior Stepdown Test (measures taken bilaterally) 
i. Involved repetitions= Max repetitions in 1 minute. 
ii. Uninvolved repetitions= Max repetitions in 1 minute. 
j. Half kneeling dorsiflexion (all measures taken bilaterally) 
i. Half kneeling difference = half kneeling involved- half kneeling non involved 
k. Single leg hop for difference (all measures taken bilaterally) 
i. Single leg hop difference = maximum involved distance – maximum non- involved 
distance  
l. Timed hop for distance (all measures taken bilaterally) 
i. Timed hop difference = time involved – time non involved  
m. Single leg triple hop for distance (all measures taken bilaterally) 
i. Single leg triple hop difference = maximum involved distance – maximum non-involved 
distance  
n. Cross over hop for distance (all measures taken bilaterally) 

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o. Cross over hop difference = maximum involved distance – maximum non-involved 
distance  
6. 12-month testing  
Tegner Activity Scale 
7. Prospective control: All prospective controls will follow the ACL reconstruction protocol at an outside 
facility.  These patients will complete outcome measures, and standardized strength assessments 
consistent with the standard current standard of care listed above.  The same data points will be 
collected. 
8. Retrospective controls:  Outcome measures (RSI, IKDC) and the results of standardized 3 and 6mo + 
assessment results will be collected. 
9. All data points listed above for all three groups will be stored in a Microsoft Excel spreadsheet on the G 
drive. 
 
Study Design/Procedures: 
 
 
The current standard of care for patients undergoing ACL reconstruction at Connecticut Children’s and 
Elite Sports Medicine involves initiation of physical therapy approximately 2-5 days after surgery.   All patients 
undergoing ACL reconstruction follow the surgeon’s ACL rehabilitation protocol.  Each participant will be 
evaluated by one of the sport physical therapists during their initial evaluation as part of the current standard of 
care for all new patients.  Patient reported outcomes and strength measurements will be conducted according to 
the surgeon’s protocol for ACL reconstruction patients.  The current rehabilitation protocol includes a 
standardized assessment at 3 months post-operative and 6-9 months post-operative.  These assessments help 
determine progression to the next phase of rehabilitation. 
 
In addition to the standard ACL protocol, patients in this study will utilize the Owen Recovery Science exercise 
protocol for BFR [18]. The following guidelines will be followed concerning exercise progression, occlusion 
pressure and difficulties with volume achievement. To determine the appropriate resistance for each exercise, 
the patient’s 1 repetition maximum (1RM) will be attained using a repetition test [19]. This test will use a 
previously validated algorithm to determine the 1RM based on the weight used to perform a 7-10 repetition test 
[20]. Patient will perform the exercise with a weight they can comfortably lift for several repetitions. Based on 
the weight or resistance used, and the patient’s perceived exertion a 1RM will be estimated using the modified 
OMNI-RES scale. The starting load for each exercise will be 20-30% of their 1RM, or bodyweight resistance 
will be used when loading is not feasible. 
 
Load progression of exercises will be based on the patient’s ability to complete the prescribed number of 
repetitions. If the patient successfully completes all 75 repetitions, they will have their 1 RM reassessed in 1-3 
session to increase the load. 
 
If the patient completes between 60-74 repetitions, they will continue with the prescribed training and increase 
the rest periods between sets 3 and 4, to 45 seconds. They then will continue with the prescribed weight until 
the patient can complete 75 repetitions for 1 to 3 sessions.  
 
If the patient completes between 45- 59 repetitions, they will continue with the prescribed weight, but will 
extend the rest period between all sets to 45 seconds. This exercise prescription will be followed until the 
patient can complete all 75 repetitions. After which the rest periods will be reduced to 30 seconds. Once the 

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patient can complete all 75 repetitions with 30 second break between sets for 1-3 session, they then would have 
their 1RM reassessed. 
 
If the patient completes less than 44 repetitions, the load will be reduced by approximately 10% until the patient 
can complete 75 repetitions in the prescribed manor. After the patient has successfully complete 1-3 sessions, 
they will have their 1RM reassessed using the previously described repetition test.  
 
 
Proposed Protocol 
Phase 1- Weeks 1 to 2 
 Quad Set: 10 second on, 10 second rest at 100% occlusion x10’ 
o  progress to isometrics at the edge of the table 60 degrees as clinically appropriate 
 Side Lying Hip Abduction, 30/15/15/15, at 80% occlusion 
 Hip Extension from prone 30/15/15/15, at 80% occlusion 
 Re-check load at the start of each Phase, to determine 1 RM (7-10RM test on leg press) 
 Total BFR time approximately 24 minutes per session, with 2 sessions per week 
 
Phase 2- Weeks 3 to 4 
 Replace Quad Set with Long Arc Quad (90-30deg), 30/15/15/15 at 80% occlusion 
 Replace Hip Extension with Leg Press (shuttle), 30/15/15/15 at 80% occlusion 
 Hip Abduction, 30/15/15/15 at 80% occlusion 
 Total BFR time approximately 24 minutes per session with 2 sessions per week 
 
Phase 3- Weeks 5 to 6 
 Long Arc Quad (90-30deg), 30/15/15/15 at 80% occlusion 
 Leg Press (shuttle), 30/15/15/15 at 80% occlusion 
 Replace Hip Abduction with Bilateral Hip Bridge, 30/15/15/15 at 80% occlusion 
 Total BFR time approximately 24 minutes per session, with 2 sessions per week 
 
Phase 4- Weeks 7 to 8 
  Leg Press (shuttle), 30/15/15/15 at 80% occlusion 
  Replace Long Arc Quad with Step Up 30/15/15/15 at 80% occlusion 
  Bilateral Hip Bridge, 30/15/15/15 at 80% occlusion 
 Total BFR time approximately 24 minutes per session, with 2 sessions per week 
 
Phase 5- Weeks 9 to 12 
 Replace Bilateral Hip Bridge with Medial Step Down, 30/15/15/15 at 80% occlusion 
 Replace Step up with Split Squat, 30/15/15/15 at 80% occlusion 
 Leg Press (shuttle), 30/15/15/15 at 80% occlusion 
 Total BFR time approximately 24 minutes per session, with 2 sessions per week 
 
Phase 6- Weeks 11 to 12 
 Progressively load exercises from phase 5 
Total BFR time approximately 24 minutes per session, with 2 sessions per week 
a. At the conclusion of each exercise completed listed in the proposed protocol above, the following will 
be recorded:  

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i) patient rating of perceived exertion (RPE) will be recorded in the exercise flow sheet.   
ii) Ability or inability to complete the exercise session 
 
b. At the conclusion of each treatment session any side effect, as previously described by Brandner et 
al, 2018, will be recorded in the patient chart.   
Sample Size Justification 
 It is our intention to use all possible patients meeting the inclusion criteria in this study. According to 
the most recent clinical data available, approximately 100 patients per year receive care for ACL knee injury 
and 25 to 50 patients per year receive physical therapy at Elite Sports Medicine following ACL reconstruction.  
.  
Accrual and Expected Duration of Accrual    
Once approved, we expect that this study can be accomplished within two to three years. The open 
period for this study will be between January 1, 2020 and December 1, 2023. 
Data Analysis:  
The endpoint of this study is when data is collected and analyzed from 20 patients who have completed a one 
year follow up from date of surgery.  
Data will be collected on all patients who meet the inclusion criteria for this study and have agreed to 
participate through the consenting process.  Descriptive statistics will be completed to help gain an overall 
understanding of the data for the effect of BFR training on lower extremity strength, mid-thigh circumference 
and outcome measures.  T-tests between strength and outcome variables for the BFR and non-BFR group to test 
if there are differences between the two groups.  Correlation tests will be used to determine association between 
lower extremity strength and BFR training.  Corrections will be made for multiple comparisons.   
We will be entering into a Data Use Agreement with University of Connecticut (UCONN) for assistance with 
data analysis and interpretation as well as statistical analysis. All data sharing procedures will be in accordance 
with Connecticut Children’s policy. All data will be de-identified prior to sharing to assure patient’s 
confidentiality. The UCONN collaborator is not engaged in human subject research (no access to identifiers) 
and will obtain an independent determination from the UCONN IRB.  
 
Study Limitations:  
There are several limitations anticipated with this study that will impact its power and external validity. These 
limitations include an inherent sampling bias with our recruitment strategy, lack of patient or participant 
blinding, and small sample size.  
Attempts will be made to reduce any potential bias by having standardized educational scripts regarding BFR 
training that each treating therapist will read to subjects prior to their first BFR session.  
Subjects in our study will likely come from the same surgeon and the same type of ACL graft (QT). This could 
be a potential limitation in the generalizability of our results to other surgeons and graft types.  
 
 
 

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Administrative Organization 
Roles and responsibilities:   
Adam Weaver, PT, DPT: Will serve as the study’s co-primary investigator and study coordinator. Adam will 
provide primary support for the SRC and IRB study protocol development and submission. He will review the 
required databases and pull the relevant data required to complete this study.  He will also aid in data 
interpretation and manuscript preparation.  
Allison Crepeau, MD: Will serve as the study’s co-investigator.  She will help with data interpretation and 
manuscript preparation. 
Arthur Fredericks, MS, PT: Will serve as the study’s co-investigator.  He will provide 
support in development of SRC and IRB documents (review of literature).  He will help with data collection   
He will provide an orthopaedic perspective to data interpretation and ultimately utilization of the results in the 
clinical setting.  
Nicholas Giampetruzzi, MS, PT: Will serve as the study’s co-investigator.  He will be essential for data 
interpretation and utilization of results.   
Dylan Roman, PT, DPT: Will serve as the study’s co-investigator.  He will provide an orthopaedic 
perspective to data interpretation and ultimately utilization of the results in the clinical setting. He will provide 
support in development of SRC and IRB documents (review of literature).  
Adel Lolic, MS, EP-C: Will serve as the study’s co-investigator. Adel with help the physical therapists with 
data collection as needed during subject tests as well as organizing tabulated results. Adel is an exercise 
technologist at Connecticut Children’s Sports Physical Therapy.  He will provide support in development of 
SRC and IRB documents, and assist with patient recruitment. 
Jennifer Prue, ATC, LAT, MEd: Will serve as the study’s co-investigator. She will help the physical therapists 
with data collection as needed during subject tests as well as organizing tabulated results. She will provide 
support in development of SRC and IRB documents, assist with patient recruitment and consenting. 
Mike Rieger, BS, CSCS: Will serve as the study’s co-investigator. He will help the physical therapists with data 
collection as needed during subject tests as well as organizing tabulated results. He assist with patient 
recruitment and consenting. 
Data Collection and Management   
a. Data collection forms: All data will be entered into a Microsoft Excel database to facilitate data 
analysis. 
b. Data collection software: Data collection software will include Microsoft Excel to organize data. 
Statistics will be run using Microsoft Excel. 
c. All outcome measures will be completed and stored in a secure online database: Microsoft Excel spreadsheet 
on G drive.   
d. Adam Weaver will oversee data management. The data will be collected by investigators, and it will 
be stored in a secured folder on the G drive.  The spreadsheet will only be accessible to those individuals 
included in this study.   
e. Information will be reviewed prior to de-identification to insure there are no errors with 
transcription. 

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f. Data quality assurance: Data that is collected will be manually verified to ensure that no information 
has been entered into Excel incorrectly. Additionally, we will randomly check 10% of data in the Excel data 
base for accuracy after initial entry to insure accuracy. 
CCMC Department of Research 
g. Record retention and confidentiality will be dictated by the current procedures in place here at 
Connecticut Children’s. All information will be stored in a private office and on a 
single password protected computer. No access to information is possible from an outside source. 
Human Subjects Protections and Ethical Conduct of the Study 
Patient confidentiality statement  
Strict measures will be required for respecting and maintaining patient confidentiality. Application for IRB 
approval is currently being created for submission, and once IRB evaluation has occurred we will make any 
changes required to ensure HIPPA compliance. Collection of a patient identifier including medical record 
numbers and the patients name is necessary to ensure comprehensive inclusion of eligible subjects and accurate 
linking of data from different data sets. The database used for the study will be password protected and stored in 
a secure folder on the G drive.  Once we have collected all the data, the data set will be frozen for analysis. At 
this time, we will completely de-identify all subjects. Medical record numbers as well as the patient’s names 
will be removed and patients will be referred to by study number only. De-identification will take place once we 
have collected all data. In the event that further time is needed prior to de-identification of the data set, we will 
request a continuation through the IRB at the time of annual review of the protocol. We expect that these 
measures will minimize any risk to confidentiality very effectively, and that any unavoidable residual risk will 
be balanced generously by the potential benefit to society of the knowledge that will be obtained through this 
research. 
Financial:  There are no financial burdens for the subjects. There are no extra costs due to travel to extra 
appointments or therapy sessions as the subjects will follow standard of care protocols for timing and quantity 
of physical therapy and follow-up appointments with their surgeon.  Again, the nature of this study will produce 
no cost to Elite Sports Medicine and Connecticut Children’s Sports Physical Therapy, and we have specific 
time set aside to accomplish our research objectives.  
Benefits:  The results of this study would benefit surgeons, rehabilitation specialists, and of course future 
patients and their families by possibly providing a method of determining the patient’s progress at an earlier 
stage and allow for early interventions to improve the patient’s outcome. 
Use of results of study 
The results of this study would provide the Elite Sports Medicine surgeons here at Connecticut Children’s 
information to determine the effectiveness and application of the use of BFR in conjunction with exercise. The 
results of this research would also provide a basis for a future study to determine how the application of BFR 
with exercise following surgery can improve patient outcomes. 
Study budget  
 
There is no budget for this study. All study personnel will be taking salary in kind for this project. 
Budget Justification 
N/A 

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Appendices (as needed) 
 
Please see attached excel file. 
References Cited  
 
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reconstruction and return to sport. Am J Sports Med 2014, 42:1567-73 
 
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51(23), 1688-1694. 
 

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[15] Tennent, D. J., Hylden, C. M., Johnson, A. E., Burns, T. C., Wilken, J. M., & Owens, J. G. (2017). Blood flow 
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