Blood Flow Restriction Training for ACL Reconstruction Recovery

Overseen By Arthur Fredericks, MSPT

Age: < 65

Sex: Any

Trial Phase: Academic

Sponsor: Connecticut Children's Medical Center

Disqualifiers: Lower extremity injury, Multiple ligament ruptures, Weight bearing restrictions, Neurologic impairments, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 3 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 5

Duration: 8 weeks

40 Participants Needed

Trial Summary

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.

What data supports the idea that Blood Flow Restriction Training for ACL Reconstruction Recovery is an effective treatment?

The available research does not provide any data on Blood Flow Restriction Training for ACL Reconstruction Recovery. Instead, it focuses on the use of tumor necrosis factor inhibitors for rheumatoid arthritis, which is unrelated to ACL recovery. ^{1 2 3 4 5}

Is Blood Flow Restriction Training safe for humans?

Blood Flow Restriction (BFR) training, which uses a tourniquet to limit blood flow during exercise, is generally considered safe when used correctly. Advances in personalized tourniquet systems have reduced the risk of injuries, such as nerve damage, by controlling pressure levels, making BFR a safer option for improving muscle strength and recovery. ^{6 7 8 9 10}

How does blood flow restriction training differ from other treatments for ACL reconstruction recovery?

Blood flow restriction training is unique because it uses a cuff to partially block blood flow during exercise, allowing patients to train with lighter weights while still gaining strength and muscle size, unlike traditional high-load training. ^{7 9 11 12 13}

What is the purpose of this trial?

While there are a number studies that have reported on the use of blood flow restriction training (BFRT) in the adult population, there is limited information about the use of BFRT in the adolescent population. This study aims to evaluate the use of BFRT in conjunction with traditional anterior ligament reconstruction (ACLR) rehabilitation in adolescents. The purpose of this study is to compare the addition of a BFRT based exercise protocol to a standard ACL rehabilitation protocol in adolescents. Does the addition of BFRT-based exercise improve strength, hypertrophy, and patient reported outcomes after ACLR in the adolescent population?

Research Team

Adam Weaver, PT, DPT

Principal Investigator

Physical Therapist

Eligibility Criteria

This trial is for adolescents who have had ACL reconstruction and were active in sports before their injury. They must have completed surgery and physical therapy at Connecticut Children's, following standard protocols, without other major knee injuries or surgeries, weight bearing restrictions over 4 weeks due to additional pathology, or follow-up procedures like arthrofibrosis.

Inclusion Criteria

Before surgery, you participated in more than 50 hours per year of intense sports and plan to go back to that level after the surgery.

I completed orthopedic surgery and physical therapy at Connecticut Children's.

I have finished my post-surgery rehab according to the standard plan.

Exclusion Criteria

I cannot attend most of my physical therapy sessions.

I must limit putting weight on my leg for over 4 weeks after surgery due to other knee issues.

I have another leg injury or had surgery on either knee.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants undergo ACL reconstruction surgery followed by a rehabilitation protocol, with the experimental group receiving additional blood flow restriction training (BFRT) exercises.

8 weeks

2 visits per week (in-person)

Follow-up

Participants are monitored for changes in strength, hypertrophy, and patient-reported outcomes at various intervals post-operation.

2 years

Regular follow-up visits at 3, 6, 9 months, and 2 years post-op

Treatment Details

Interventions

• Delfi Personalized Tourniquet System

Trial Overview The study tests if adding Blood Flow Restriction Training (BFRT) using the Delfi Personalized Tourniquet System to standard ACL rehab improves strength, muscle growth, and patient outcomes in adolescents after ACL reconstruction compared to just the standard rehab protocol.

Participant Groups

Group I: BFR Intervention Group Experimental Treatment 1 Intervention

In addition to the standard ACL rehabilitation protocol, the experimental group will complete 2 exercises using the Delfi BFR cuff 2x/week for 8 weeks during their treatment session at Connecticut Children's Sports Physical Therapy on the second post-operative visit. Cuff size will be determined by patient thigh circumference Limb occlusion pressure will be determined in supine position and all exercises will be completed at 80% occlusion. Long Arc Quadriceps (LAQ) progression Shuttle progression Post-op visit 2- 2 weeks Quadriceps Set Standing Straight Leg Raise 2 weeks-4 weeks Available range LAQ Standing terminal knee extension 4 weeks-8 weeks LAQ (0-90°) Single Limb Shuttle/Leg Press

Group II: No Intervention/Control Group Active Control 1 Intervention

In addition to the standard ACL rehabilitation protocol, the control group will complete the same exercises as the experimental group starting on the second post-operative visit. Long Arc Quadriceps (LAQ) progression Shuttle progression Post-op visit 2- 2 weeks Quadriceps Set Standing Straight Leg Raise 2 weeks-4 weeks Available range LAQ Standing terminal knee extension 4 weeks-8 weeks LAQ (0-90°) Single Limb Shuttle/Leg Press

Who Is Running the Clinical Trial?

Connecticut Children's Medical Center

Lead Sponsor

Trials

76

Recruited

30,000+

University of Connecticut

Collaborator

Trials

194

Recruited

162,000+

Findings from Research

A consensus among 15 Italian rheumatologists found that starting TNF inhibitors (TNFi) immediately in DMARDs-naïve patients with early rheumatoid arthritis (RA) does not significantly improve clinical, functional, or radiographic outcomes compared to a step-up approach within 12 weeks.

The review included 6 studies with a total of 1080 records, indicating that while TNFi can be effective, the optimal timing for its use in treatment strategies for early RA remains uncertain and requires further investigation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Immediate treatment with tumour necrosis factor inhibitors in synthetic disease-modifying anti-rheumatic drugs-naïve patients with rheumatoid arthritis: results of a modified Italian Expert Consensus. Bortoluzzi, A., Valesini, G., D'Angelo, S., et al.[2018]

In a study of 1,818 elderly patients with rheumatoid arthritis undergoing major surgeries, the timing of infliximab infusion before surgery did not affect the risk of post-operative infections or mortality.

Post-operative infection rates varied among different surgical procedures, but there was no increased risk associated with receiving infliximab closer to the time of surgery, suggesting that withholding TNF inhibitors may not be necessary.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Pre-operative withholding of infliximab and the risk of infections after major surgery in patients with rheumatoid arthritis. Ward, MM., Dasgupta, A.[2021]

Tumor necrosis factor inhibitors (TNFi) are effective biologic therapies for rheumatoid arthritis (RA) with a proven clinical efficacy, but they are associated with a range of potential adverse events, from mild to serious.

Despite the risks, the overall safety profile of TNFi is reasonable, and with proper screening and ongoing monitoring, the benefits of treatment generally outweigh the risks, especially when compared to the dangers of untreated RA.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The safety of tumor necrosis factor-alpha inhibitors in the treatment of rheumatoid arthritis. Hernández, MV., Sanmartí, R., Cañete, JD.[2017]

In a study comparing 67 rheumatoid arthritis patients using a tapering strategy for TNF inhibitors to 77 patients on a standard regimen, both groups maintained similar disease activity scores (DAS28) after one year, indicating effective disease control.

The tapering group experienced significant reductions in drug administration (up to 52.9% for certain medications) without an increase in flare incidence, suggesting that tapering TNF inhibitors can be a safe and effective strategy for managing rheumatoid arthritis.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Comparing a tapering strategy to the standard dosing regimen of TNF inhibitors in rheumatoid arthritis patients with low disease activity. Plasencia, C., Wolbink, G., Krieckaert, CL., et al.[2017]

In a study involving 97 rheumatoid arthritis patients, tapering TNF inhibitor doses by 33% did not lead to an increase in disease flares, suggesting it is a safe option for patients in sustained remission.

However, tapering by 66% resulted in a higher risk of disease flares, indicating that while some reduction in medication may be feasible, larger reductions could compromise patient stability.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Optimizing treatment with tumour necrosis factor inhibitors in rheumatoid arthritis-a proof of principle and exploratory trial: is dose tapering practical in good responders? Ibrahim, F., Lorente-Cánovas, B., Doré, CJ., et al.[2022]

Tourniquets are effective in providing blood-free surgical fields in orthopaedic surgery, but they carry risks of nerve, muscle, and tissue injuries; however, advancements in tourniquet technology have reduced these risks by lowering pressure levels.

Recent evidence shows that tourniquets can also be used for blood flow restriction (BFR) therapy, which helps reduce muscle atrophy and improve strength, thus enhancing recovery outcomes when used appropriately.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Tourniquet-induced nerve compression injuries are caused by high pressure levels and gradients - a review of the evidence to guide safe surgical, pre-hospital and blood flow restriction usage. Masri, BA., Eisen, A., Duncan, CP., et al.[2020]

In a study of 46 subjects over 8 weeks, both blood flow restriction (BFR) training and traditional exercise led to significant strength gains in the rotator cuff muscles, but there was no difference in strength improvements between the two methods.

Both groups also experienced increases in supraspinatus tendon thickness, indicating that low-load, high-repetition exercises can effectively enhance rotator cuff strength and tendon size, regardless of BFR application.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Blood Flow Restriction Training for the Rotator Cuff: A Randomized Controlled Trial. Brumitt, J., Hutchison, MK., Kang, D., et al.[2023]

In a study of 29 participants, a minimum blood flow restriction pressure of 50% limb occlusion pressure (LOP) was necessary to significantly reduce arterial blood flow in the lower limbs, indicating a threshold for effective blood flow restriction.

The study found no significant differences in vessel diameter or blood flow at higher occlusion pressures (60% to 90% LOP), suggesting that pressures above 50% LOP may not provide additional benefits for blood flow restriction during exercise.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Acute Blood Flow Responses to Varying Blood Flow Restriction Pressures in the Lower Limb. Hornikel, B., Saffold, KS., Mota, JA., et al.[2023]

Blood flow restriction (BFR) training, when combined with traditional resistance training, can significantly enhance strength in healthy athletes, with 78% of studies showing notable improvements compared to control groups.

BFR training also has the potential to increase muscle size and improve sport-specific performance metrics, with 50% of studies reporting muscle size gains and 75% showing enhancements in athletic performance measures.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Blood Flow Restriction Training for Athletes: A Systematic Review. Wortman, RJ., Brown, SM., Savage-Elliott, I., et al.[2021]

In a study involving 24 healthy subjects, low-weight training combined with blood flow restriction (BFR) resulted in significantly greater strength gains in both proximal and distal muscle groups compared to low-weight training without BFR, with increases in shoulder strength by up to 30%.

BFR training also led to significant increases in arm and forearm circumferences, indicating enhanced muscle hypertrophy, while no adverse events were reported, suggesting that this method is safe for participants.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Upper-extremity blood flow restriction: the proximal, distal, and contralateral effects-a randomized controlled trial. Bowman, EN., Elshaar, R., Milligan, H., et al.[2020]

Blood flow restriction (BFR) training combined with low-intensity resistance training (LIRT) shows promise in reducing quadriceps muscle atrophy after ACL reconstruction, with three out of four studies indicating an increase in muscle cross-sectional area.

The systematic review assessed four studies with moderate strength, suggesting that while BFR may be beneficial, further research is needed before it can be widely recommended in clinical practice.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A SYSTEMATIC REVIEW OF THE EFFECTS OF BLOOD FLOW RESTRICTION TRAINING ON QUADRICEPS MUSCLE ATROPHY AND CIRCUMFERENCE POST ACL RECONSTRUCTION. Charles, D., White, R., Reyes, C., et al.[2022]

Blood flow restriction (BFR) training is considered a safe and effective method for improving musculoskeletal training outcomes, supported by 25 years of research.

There is a need for standardized, evidence-based protocols for BFR training among health professionals in South Africa to ensure its proper and safe application during rehabilitation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Blood flow restriction training in South Africa - a panel discussion. Evans, RW., Ganda, J., van Schalkwyk, L., et al.[2023]

This study will evaluate the effectiveness of blood flow restriction training (BFRT) on improving quadriceps strength and knee biomechanics in 60 participants aged 15 to 40 with ACL tears, using a randomized, double-blind, placebo-controlled design.

If successful, BFRT could provide a targeted intervention to address long-lasting quadriceps strength deficits after ACL reconstruction, potentially leading to better recovery outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effect of Blood Flow Restriction Training on Quadriceps Muscle Strength, Morphology, Physiology, and Knee Biomechanics Before and After Anterior Cruciate Ligament Reconstruction: Protocol for a Randomized Clinical Trial. Erickson, LN., Lucas, KCH., Davis, KA., et al.[2020]

References

1. England pubmed.ncbi.nlm.nih.gov

Immediate treatment with tumour necrosis factor inhibitors in synthetic disease-modifying anti-rheumatic drugs-naïve patients with rheumatoid arthritis: results of a modified Italian Expert Consensus. [2018]

2. England pubmed.ncbi.nlm.nih.gov

Pre-operative withholding of infliximab and the risk of infections after major surgery in patients with rheumatoid arthritis. [2021]

3. England pubmed.ncbi.nlm.nih.gov

The safety of tumor necrosis factor-alpha inhibitors in the treatment of rheumatoid arthritis. [2017]

4. Italy pubmed.ncbi.nlm.nih.gov

Comparing a tapering strategy to the standard dosing regimen of TNF inhibitors in rheumatoid arthritis patients with low disease activity. [2017]

5. England pubmed.ncbi.nlm.nih.gov

Optimizing treatment with tumour necrosis factor inhibitors in rheumatoid arthritis-a proof of principle and exploratory trial: is dose tapering practical in good responders? [2022]

6. England pubmed.ncbi.nlm.nih.gov

Tourniquet-induced nerve compression injuries are caused by high pressure levels and gradients - a review of the evidence to guide safe surgical, pre-hospital and blood flow restriction usage. [2020]

7. United States pubmed.ncbi.nlm.nih.gov

Blood Flow Restriction Training for the Rotator Cuff: A Randomized Controlled Trial. [2023]

8. United States pubmed.ncbi.nlm.nih.gov

Acute Blood Flow Responses to Varying Blood Flow Restriction Pressures in the Lower Limb. [2023]

9. United States pubmed.ncbi.nlm.nih.gov

Blood Flow Restriction Training for Athletes: A Systematic Review. [2021]

10. United States pubmed.ncbi.nlm.nih.gov

Upper-extremity blood flow restriction: the proximal, distal, and contralateral effects-a randomized controlled trial. [2020]

11. United States pubmed.ncbi.nlm.nih.gov

A SYSTEMATIC REVIEW OF THE EFFECTS OF BLOOD FLOW RESTRICTION TRAINING ON QUADRICEPS MUSCLE ATROPHY AND CIRCUMFERENCE POST ACL RECONSTRUCTION. [2022]

12. South Africa pubmed.ncbi.nlm.nih.gov

Blood flow restriction training in South Africa - a panel discussion. [2023]

13. United States pubmed.ncbi.nlm.nih.gov

Effect of Blood Flow Restriction Training on Quadriceps Muscle Strength, Morphology, Physiology, and Knee Biomechanics Before and After Anterior Cruciate Ligament Reconstruction: Protocol for a Randomized Clinical Trial. [2020]