Anterior Cruciate Ligament Tear
Conditions
Brief summary
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
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.
Interventions
DEVICEBlood flow restriction
Intervention restricts blood flow to the lower limb as a percentage of the limb occlusion pressure
Sponsors
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
University of Washington
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Hip Internal Rotation Moment | 6 minutes | Maximum difference in internal rotation moment of hip while performing exercise between baseline and blood flow restriction condition. Measured in Newton meters per kilogram |
| Hip Extension Moment | 6 minutes | Maximum difference in extension moment of hip while performing exercise between baseline and blood flow restriction condition. Measured in Newton meters per kilogram. |
| Hip Adduction Moment | 6 minutes | Maximum difference in adduction moment of hip while performing exercise between baseline and blood flow restriction condition. Measured in Newton meters per kilogram |
| Knee Flexion | 6 minutes | Maximum difference in flexion motion of knee while performing exercise between baseline and blood flow restriction condition. Measured in degrees |
| Knee Internal Rotation | 6 minutes | Maximum difference in internal rotation of knee while performing exercise between baseline and blood flow restriction condition. Measured in degrees |
| Knee Varus | 6 minutes | Maximum difference in varus motion of knee while performing exercise between baseline and blood flow restriction condition. Measured in degrees |
| Hip Flexion | 6 minutes | Maximum difference in flexion motion of hip while performing exercise between baseline and blood flow restriction condition. Measured in degrees |
| Hip Adduction | 6 minutes | Maximum difference in adduction motion of hip while performing exercise between baseline and blood flow restriction condition. Measured in degrees |
| Hip Internal Rotation | 6 minutes | Maximum difference in internal rotation motion of hip while performing exercise between baseline and blood flow restriction condition. Measured in degrees |
| Knee Extension Moment | 6 minutes | Maximum difference in extension moment of knee while performing exercise between baseline and blood flow restriction condition. Measured in Newton meters per kilogram |
| Knee Internal Rotation Moment | 6 minutes | Maximum difference in internal rotation moment of knee while performing exercise between baseline and blood flow restriction condition. Measured in Newton meters per kilogram |
| Knee Adduction Moment | 6 minutes | Maximum difference in adduction moment of knee while performing exercise between baseline and blood flow restriction condition. Measured in Newton meters per kilogram |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Exercise Discomfort Score | 6 minutes | Numerical Analogue Scale, 0-10, higher scores indicate greater discomfort |
| Exercise Difficulty Score | 6 minutes | Numerical Analogue Scale, 0-10, higher scores indicate greater difficulty |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Anterior Cruciate Ligament Reconstruction Group Single session blood flow restriction of lower limb to individuals who have undergone anterior ligament reconstruction surgery
Blood flow restriction: Intervention restricts blood flow to the lower limb as a percentage of the limb occlusion pressure | 20 |
| Control Group Single session blood flow restriction of lower limb to individuals who have no musculoskeletal injuries
Blood flow restriction: Intervention restricts blood flow to the lower limb as a percentage of the limb occlusion pressure | 20 |
| Total | 40 |
Baseline characteristics
| Characteristic | Anterior Cruciate Ligament Reconstruction Group | Total | Control Group |
|---|---|---|---|
| Age, Continuous | 30.6 years | 29.3 years | 28 years |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 2 Participants | 3 Participants | 1 Participants |
| Race (NIH/OMB) Black or African American | 1 Participants | 2 Participants | 1 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) White | 17 Participants | 35 Participants | 18 Participants |
| Region of Enrollment United States | 20 participants | 40 participants | 20 participants |
| Sex: Female, Male Female | 12 Participants | 23 Participants | 11 Participants |
| Sex: Female, Male Male | 8 Participants | 17 Participants | 9 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 20 | 0 / 20 |
| other Total, other adverse events | 0 / 20 | 0 / 20 |
| serious Total, serious adverse events | 0 / 20 | 0 / 20 |
Outcome results
Primary
Hip Adduction
Maximum difference in adduction motion of hip while performing exercise between baseline and blood flow restriction condition. Measured in degrees
Time frame: 6 minutes
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Anterior Cruciate Ligament Reconstruction Group | Hip Adduction | 0.61 Degrees | Standard Deviation 1.9 |
| Control Group | Hip Adduction | 1.52 Degrees | Standard Deviation 2.6 |
Primary
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
Time frame: 6 minutes
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Anterior Cruciate Ligament Reconstruction Group | Hip Adduction Moment | -0.01 Newton meters per kilogram | Standard Deviation 0.1 |
| Control Group | Hip Adduction Moment | -0.07 Newton meters per kilogram | Standard Deviation 0.14 |
Primary
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.
Time frame: 6 minutes
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Anterior Cruciate Ligament Reconstruction Group | Hip Extension Moment | 0.09 Newton meters per kilogram | Standard Deviation 0.16 |
| Control Group | Hip Extension Moment | 0.2 Newton meters per kilogram | Standard Deviation 0.14 |
Primary
Hip Flexion
Maximum difference in flexion motion of hip while performing exercise between baseline and blood flow restriction condition. Measured in degrees
Time frame: 6 minutes
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Anterior Cruciate Ligament Reconstruction Group | Hip Flexion | -1.73 Degrees | Standard Deviation 2.27 |
| Control Group | Hip Flexion | -2.9 Degrees | Standard Deviation 8.15 |
Primary
Hip Internal Rotation
Maximum difference in internal rotation motion of hip while performing exercise between baseline and blood flow restriction condition. Measured in degrees
Time frame: 6 minutes
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Anterior Cruciate Ligament Reconstruction Group | Hip Internal Rotation | 1.49 Degrees | Standard Deviation 2.37 |
| Control Group | Hip Internal Rotation | 1.05 Degrees | Standard Deviation 2.6 |
Primary
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
Time frame: 6 minutes
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Anterior Cruciate Ligament Reconstruction Group | Hip Internal Rotation Moment | -0.02 Newton meters per kilogram | Standard Deviation 0.13 |
| Control Group | Hip Internal Rotation Moment | 0.05 Newton meters per kilogram | Standard Deviation 0.05 |
Primary
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
Time frame: 6 minutes
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Anterior Cruciate Ligament Reconstruction Group | Knee Adduction Moment | 0.06 Newton meters per kilogram | Standard Deviation 0.05 |
| Control Group | Knee Adduction Moment | 0.12 Newton meters per kilogram | Standard Deviation 0.07 |
Primary
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
Time frame: 6 minutes
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Anterior Cruciate Ligament Reconstruction Group | Knee Extension Moment | 0.31 Newton meters per kilogram | Standard Deviation 0.21 |
| Control Group | Knee Extension Moment | 0.6 Newton meters per kilogram | Standard Deviation 0.26 |
Primary
Knee Flexion
Maximum difference in flexion motion of knee while performing exercise between baseline and blood flow restriction condition. Measured in degrees
Time frame: 6 minutes
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Anterior Cruciate Ligament Reconstruction Group | Knee Flexion | -0.05 Degrees | Standard Deviation 2 |
| Control Group | Knee Flexion | 0.01 Degrees | Standard Deviation 5.14 |
Primary
Knee Internal Rotation
Maximum difference in internal rotation of knee while performing exercise between baseline and blood flow restriction condition. Measured in degrees
Time frame: 6 minutes
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Anterior Cruciate Ligament Reconstruction Group | Knee Internal Rotation | 1.19 Degrees | Standard Deviation 1.4 |
| Control Group | Knee Internal Rotation | -0.03 Degrees | Standard Deviation 1.97 |
Primary
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
Time frame: 6 minutes
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Anterior Cruciate Ligament Reconstruction Group | Knee Internal Rotation Moment | -0.01 Newton meters per kilogram | Standard Deviation 0.05 |
| Control Group | Knee Internal Rotation Moment | -0.02 Newton meters per kilogram | Standard Deviation 0.07 |
Primary
Knee Varus
Maximum difference in varus motion of knee while performing exercise between baseline and blood flow restriction condition. Measured in degrees
Time frame: 6 minutes
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Anterior Cruciate Ligament Reconstruction Group | Knee Varus | 0.12 Degrees | Standard Deviation 1.25 |
| Control Group | Knee Varus | -0.36 Degrees | Standard Deviation 2.61 |
Secondary
Exercise Difficulty Score
Numerical Analogue Scale, 0-10, higher scores indicate greater difficulty
Time frame: 6 minutes
| Arm | Measure | Value (MEAN) |
|---|---|---|
| Anterior Cruciate Ligament Reconstruction Group | Exercise Difficulty Score | 4.0 units on a scale |
| Control Group | Exercise Difficulty Score | 5.0 units on a scale |
Secondary
Exercise Discomfort Score
Numerical Analogue Scale, 0-10, higher scores indicate greater discomfort
Time frame: 6 minutes
| Arm | Measure | Value (MEAN) |
|---|---|---|
| Anterior Cruciate Ligament Reconstruction Group | Exercise Discomfort Score | 4.0 units on a scale |
| Control Group | Exercise Discomfort Score | 4.5 units on a scale |