Personalized Blood Flow Restriction for Anterior Cruciate Ligament Rehabilitation

This is a cross-sectional study on the use of personalized blood flow restriction during rehabilitation exercises and its effects on biomechanics on people who have had an anterior cruciate ligament reconstruction and healthy controls

Study Overview

• Status: Completed
• Conditions: Anterior Cruciate Ligament Tear
• Intervention / Treatment: Device: Blood flow restriction

Detailed Description

Rehabilitation after surgical reconstruction of the anterior cruciate ligament (ACL) aims to reestablish the function of the knee. However, regaining previous levels of strength is challenging, with long-term muscle weakness frequently reported and thought to play a key role in the increased risk of knee osteoarthritis for individuals with a history of ACL damage. Effectively building muscle strength requires exercises with high resistance loads, however the joint stress and risk of further injury makes these types of activities inappropriate and unsafe for those rehabilitating after ACL reconstruction surgery and other injuries. Personalized blood flow restriction (BFR) training is a technique where the blood flow to the muscles being exercised is controlled by a pressure cuff to a predefined level, and has been shown to increase strength while exercising with significantly lower loads. Early results have been promising, however the effects of BFR on the biomechanics of the exercise as well as the acceptability in the ACL reconstruction population have not been explored. In this application, we propose a cross-sectional study designed to test the acceptability of BFR training for those undergoing rehabilitation from ACL reconstruction surgery and healthy controls during free standing exercises. We will also investigate the biomechanical effects of this rehabilitation technique. This application is part of a larger program of musculoskeletal research in this area being developed by the team. The results from the proposed project will inform the design of a clinical trial of personalized BFR after ACL reconstruction.

• Study Type: Interventional
• Enrollment (Actual): 40
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Washington
    • Seattle, Washington, United States, 98195
      • University of Washington Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria (ACL-R group):

• Must be undergoing rehabilitation for anterior cruciate ligament reconstruction surgery
• Must be at least 3 months post surgery.
• Attending clinician should confirm that they are able to take part in the trial

Exclusion Criteria:

• Any other orthopaedic, neurological, or other condition within the last 12 months that would affect ability to carry out the required exercises
• Any medical conditions that may affect circulation including, but not limited to, deep vein thrombosis, high blood pressure, and cardiac disease

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Anterior cruciate ligament reconstruction group; Single session blood flow restriction of lower limb to individuals who have undergone anterior ligament reconstruction surgery	Device: Blood flow restriction; Intervention restricts blood flow to the lower limb as a percentage of the limb occlusion pressure
Active Comparator: Control group; Single session blood flow restriction of lower limb to individuals who have no musculoskeletal injuries	Device: Blood flow restriction; Intervention restricts blood flow to the lower limb as a percentage of the limb occlusion pressure

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Knee Flexion	Maximum difference in flexion motion of knee while performing exercise between baseline and blood flow restriction condition. Measured in degrees	6 minutes
Knee Internal Rotation	Maximum difference in internal rotation of knee while performing exercise between baseline and blood flow restriction condition. Measured in degrees	6 minutes
Knee Varus	Maximum difference in varus motion of knee while performing exercise between baseline and blood flow restriction condition. Measured in degrees	6 minutes
Hip Flexion	Maximum difference in flexion motion of hip while performing exercise between baseline and blood flow restriction condition. Measured in degrees	6 minutes
Hip Adduction	Maximum difference in adduction motion of hip while performing exercise between baseline and blood flow restriction condition. Measured in degrees	6 minutes
Hip Internal Rotation	Maximum difference in internal rotation motion of hip while performing exercise between baseline and blood flow restriction condition. Measured in degrees	6 minutes
Knee Extension Moment	Maximum difference in extension moment of knee while performing exercise between baseline and blood flow restriction condition. Measured in Newton meters per kilogram	6 minutes
Knee Internal Rotation Moment	Maximum difference in internal rotation moment of knee while performing exercise between baseline and blood flow restriction condition. Measured in Newton meters per kilogram	6 minutes
Knee Adduction Moment	Maximum difference in adduction moment of knee while performing exercise between baseline and blood flow restriction condition. Measured in Newton meters per kilogram	6 minutes
Hip Extension Moment	Maximum difference in extension moment of hip while performing exercise between baseline and blood flow restriction condition. Measured in Newton meters per kilogram.	6 minutes
Hip Adduction Moment	Maximum difference in adduction moment of hip while performing exercise between baseline and blood flow restriction condition. Measured in Newton meters per kilogram	6 minutes
Hip Internal Rotation Moment	Maximum difference in internal rotation moment of hip while performing exercise between baseline and blood flow restriction condition. Measured in Newton meters per kilogram	6 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Exercise Difficulty Score	Numerical Analogue Scale, 0-10, higher scores indicate greater difficulty	6 minutes
Exercise Discomfort Score	Numerical Analogue Scale, 0-10, higher scores indicate greater discomfort	6 minutes

Collaborators and Investigators

• Sponsor: University of Washington
• Collaborators: National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
• Investigators: Principal Investigator: Scott Telfer, EngD, University of Washington

Study record dates

Study Major Dates

• Study Start (Actual): May 8, 2018
• Primary Completion (Actual): November 2, 2020
• Study Completion (Actual): November 2, 2020

Study Registration Dates

• First Submitted: November 2, 2020
• First Submitted That Met QC Criteria: November 13, 2020
• First Posted (Actual): November 19, 2020

Study Record Updates

• Last Update Posted (Actual): February 28, 2022
• Last Update Submitted That Met QC Criteria: February 3, 2022
• Last Verified: February 1, 2022

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Wounds and Injuries; Leg Injuries; Knee Injuries; Anterior Cruciate Ligament Injuries
• Other Study ID Numbers: STUDY00004543; 5P30AR072572-02 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: Yes
• IPD Plan Description: Data will be made available to researchers on request. Dataset includes all kinematic, kinetic and patient reported data.
• IPD Sharing Time Frame: 11/19/2021 - 11/18/2026
• IPD Sharing Supporting Information Type: Study Protocol; Analytic Code

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: Yes