Blood Flow Restriction Exercise in Patients With an Achilles Tendon Rupture

NCT ID: NCT06434272

Last Updated: 2025-04-17

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: NA
• Total Enrollment: 218 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2025-01-28
• Study Completion Date: 2028-01-09

Brief Summary

The goal of this clinical trial is to gain insights into the effects of Blood Flow Restriction Exercise (BFRE) in patients with an acute Achilles tendon Rupture. The main questions it aims to answer are:

Is BFRE an effective adjunct to usual care when compared with only usual care? When is the optimal timing for initiating BFRE: In the early treatment stage or at the later stage after hospital treatment? Participants will receive an intervention comprising 12 weeks of BFRE as an adjunct to usual care.

• Either in the initial 1-12 weeks after Achilles tendon rupture, or
• In the following 13-24 weeks after Achilles tendon rupture

Researchers will compare the two groups at 13 weeks (3 months) to compare BFRE to usual care, and at 25 weeks (6 months) to compare the two time points for initiating BFRE (early vs. late).

Detailed Description

This is an assessor-blinded, randomized, controlled multicenter trial with patients allocated 1:1 to one of two parallel groups, with follow-up times at weeks 13 and 25 after allocation.

Patients with an acute Achilles tendon rupture treated non-surgically are eligible for inclusion. All patients will receive a 12-week BFRE program, either in weeks 1-12 or 13-24 post allocation, as an add-on to usual care.

The BFRE program is performed three times weekly on the injured leg at 80% of the limb occlusion pressure required to restrict the arterial blood flow fully.

Outcome measures are assessed at baseline, week 13, and week 25 after allocation. The primary outcome at the week 13 follow-up is the Single-Leg Heel-Raise test which assesses the patient's ability to raise the heel of the injured leg a minimum of 2 cm. The primary outcome at the week 25 follow-up is the Achilles Total Tendon Rupture Score which assesses the patient's self-reported symptoms and physical activity.

During most of the initial trial phase (weeks 1-12), patients are treated at local hospitals, where recruitment, assessment, and randomization occur. Usual care at the hospitals consists of ankle immobilization with a gradual return to weight-bearing in the following weeks. In the latter half of the trial phase (weeks 13-24), patients have transitioned to municipal care, where usual care includes diverse exercises performed at home or training facilities.

Conditions

Achilles Tendon Rupture

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: SINGLE

Study Groups

Early initiated Blood Flow Restriction Exercise

Receives an intervention in adjunct to usual care in weeks 1-12, and continues with usual care in weeks 13-24.

Group Type: EXPERIMENTAL

Early exercise with partial Blood Flow Restriction

Intervention Type: OTHER

The intervention comprises of 12 weeks of blood flow restriction exercise in weeks 1-12 after injury. Three weekly exercise sessions are performed. Six supervised sessions are provided during the 12 weeks.

Blood flow restriction of 80% of the limb occlusion pressure required to fully restrict the arterial blood flow is employed.

The intervention comprises three exercises: Seated leg extension, standing knee flexion, and seated heel-rise performed at home as an adjunct to usual care treatment.

Each exercise is performed in four sets of 30, 15, 15, +1 repetitions, with the fourth set (+1) being as many repetitions as possible.

Pause in between sets is 30 seconds. Pause in between exercises are 120 seconds.

In weeks 13-24, patients in this arm follow usual care treatment.

Late initiated Blood Flow Restriction Exercise

Receives usual care in weeks 1-12, and receives an intervention in adjunct to usual care weeks 13-24.

Group Type: EXPERIMENTAL

Late exercise with partial Blood Flow Restriction

Intervention Type: OTHER

The intervention comprises of 12 weeks of blood flow restriction exercise in weeks 13-24 after injury. Three weekly exercise sessions are performed. Six supervised sessions are provided during the 12 weeks.

Blood flow restriction of 80% of the limb occlusion pressure required to fully restrict the arterial blood flow is employed.

The intervention comprises three exercises: Leg press in machine, heel-rise in machine, knee flexion in machine performed at training facilities as an adjunct to usual care treatment. If facilities are unavailable, three home-based exercises will be provided.

Each exercise, regardless of study arm, is performed in four sets of 30, 15, 15, +1 repetitions, with the fourth set (+1) being as many repetitions as possible.

In weeks 1-12, patients in this arm follow usual care treatment.

Interventions

Early exercise with partial Blood Flow Restriction

The intervention comprises of 12 weeks of blood flow restriction exercise in weeks 1-12 after injury. Three weekly exercise sessions are performed. Six supervised sessions are provided during the 12 weeks.

Blood flow restriction of 80% of the limb occlusion pressure required to fully restrict the arterial blood flow is employed.

The intervention comprises three exercises: Seated leg extension, standing knee flexion, and seated heel-rise performed at home as an adjunct to usual care treatment.

Each exercise is performed in four sets of 30, 15, 15, +1 repetitions, with the fourth set (+1) being as many repetitions as possible.

Pause in between sets is 30 seconds. Pause in between exercises are 120 seconds.

In weeks 13-24, patients in this arm follow usual care treatment.

Intervention Type: OTHER

Late exercise with partial Blood Flow Restriction

The intervention comprises of 12 weeks of blood flow restriction exercise in weeks 13-24 after injury. Three weekly exercise sessions are performed. Six supervised sessions are provided during the 12 weeks.

Blood flow restriction of 80% of the limb occlusion pressure required to fully restrict the arterial blood flow is employed.

The intervention comprises three exercises: Leg press in machine, heel-rise in machine, knee flexion in machine performed at training facilities as an adjunct to usual care treatment. If facilities are unavailable, three home-based exercises will be provided.

Each exercise, regardless of study arm, is performed in four sets of 30, 15, 15, +1 repetitions, with the fourth set (+1) being as many repetitions as possible.

In weeks 1-12, patients in this arm follow usual care treatment.

Intervention Type: OTHER

Other Intervention Names

BFR; BFRE; Blood Flow Restriction Exercise; BFR-T; Blood Floow Restriciton Training; LL-BFR; Low Load Blood Flow Restriction; BFR; BFRE; Blood Flow Restriction Exercise; BFR-T; Blood Flow Restriction Training; LL-BFR; Low Load Blood Flow Restriction

Eligibility Criteria

Inclusion Criteria

• aged 18 years or older
• have started initial treatment within 72 hours of Achilles tendon rupture
• understand written and spoken Danish

Exclusion Criteria

• bilateral Achilles tendon rupture
• previous Achilles tendon rupture in either leg
• decreased lower extremity function, caused by conditions other than Achilles tendon rupture
• treated with fluoroquinolones within the last six months
• treated with corticosteroid injection(s) in the area near the Achilles tendon within the last six months.
• diabetes
• previous diagnosed thrombosis
• Known atherosclerosis in the peripheral arteries of the lower limb
• other reasons for exclusion (cognitive deficits, inability to provide informed consent, requiring cast-treatment due to low compliance regarding gradual wedge removal, etc.)

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Aarhus University Hospital

OTHER

Sponsor Role: collaborator

Aalborg University Hospital

OTHER

Sponsor Role: collaborator

Gødstrup Hospital

OTHER

Sponsor Role: collaborator

Regionshospitalet Horsens

OTHER

Sponsor Role: collaborator

University of Aarhus

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Andreas Bentzen, MHSc

Role: PRINCIPAL_INVESTIGATOR

University of Aarhus

Inger Mechlenburg, DMSc

Role: STUDY_DIRECTOR

University of Aarhus

Per H. Gundtoft, MD, PhD

Role: STUDY_DIRECTOR

Aarhus University Hospital

Stian L. Jørgensen, PT, PhD

Role: STUDY_DIRECTOR

Regionshospitalet Horsens

Locations

Aarhus University Hospital

Aarhus N, , Denmark

Site Status: RECRUITING

Countries

Denmark

Central Contacts

Andreas Bentzen, MHSc

Role: CONTACT

andreas.bentzen@clin.au.dk

4553109112

Inger Mechlenburg, DMSc

Role: CONTACT

inger.mechlenburg@clin.au.dk

4521679062

Facility Contacts

Inger Mechlenburg

Role: primary

+45 21679062

Other Identifiers

BEAN (1-10-72-192-23)

Identifier Type: -

Identifier Source: org_study_id