ACL Tear
Conditions
Brief summary
The study is a prospective randomized control trial consisting of subjects requiring ACL reconstruction with BTB autograft. Subjects were randomly divided into two groups following their inclusion in the study. One group underwent the normal ACL rehab protocol as determined by the participating surgeons. The study group underwent normal ACL rehab modified by use of a tourniquet for blood flow restriction during selected exercises.
Detailed description
On the day of the procedure, the surgeon will measure the subject's thigh circumference 1/3 distance from the superior pole of the patella to the inguinal crease. The subject will then undergo the normal BTB autograft ACL reconstruction procedure. A subject will be excluded from the study if a meniscal repair is performed. At the subject's two week post-operative clinic visit, the physician will measure thigh circumference at 1/3 distance from the superior pole of the patella to the inguinal crease. Study group subjects will begin physical therapy instructed BFR exercises at two weeks post operatively. Study group subjects will be taken through normal ACL rehab protocol as well as BFR exercises. Control group subjects will do the same exercises and formal physical therapy rehab protocol as the study group without BFR. The BFR exercises will consist of: bilateral leg press week 3-10, eccentric leg press weeks 4-10, hamstring curl week 4-6, eccentric hamstring curl weeks 7-10, straight leg press weeks 6-10. The pressure used will be elevated to occluded blood flow by 80% (80% occlusion pressure) which will be determined for each individual subject. Subjects will do exercises at 20% of 1RM in 4 sets of 30-15-15-15 repetitions separated by 30 seconds of rest. Repetition maximum (1RM) will be determined by the contralateral leg, using the greatest amount of weight with full range of motion and proper form. This will be done over three separate tries, separated by one minute breaks. Resistance loads will be adjusted every 2 weeks as strength improves. During the exercise protocol, if patients are unable to complete the prescribed amount of repetitions, rest periods between sets will be increased as needed. The control group will do these exercises without BFR. Both study and control groups will also do the surgeons' standard post-ACL reconstruction physical therapy protocol. Cuff pressures will be determined using the Loenneke et al outline, based off of thigh circumference and estimated cuff pressure for 50% artery occlusion \[19\]. Body composition (DEXA), bone density (DEXA), IKDC and Tegner Lysholm scores will be recorded at first rehabilitation visit, two weeks, eight weeks and 12 weeks following the initiation of rehab (1 wk following surgery). Y- balance, single leg squat distance, and single leg step down will be measured at 8 weeks and 12 weeks of rehab. Return to play will be recorded as the number of months after the day of operation until subject returns to sport.
Interventions
The study group underwent normal ACL rehab modified by use of a tourniquet for blood flow restriction during selected exercises.
Sponsors
The Methodist Hospital Research Institute
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
Participants were randomized to either receive standard physical therapy or standard physical therapy with blood flow restriction therapy.
Eligibility
Sex/Gender
ALL
Age
18 Years to 35 Years
Healthy volunteers
Yes
Inclusion criteria
* Ages 18-35 * Received ACL surgery with a patellar tendon autograft
Exclusion criteria
* Concomitant meniscal tear or additional ligamentous injury to the knee * Obesity (BMI\>30) * Diabetes * Cardiovascular, renal, liver or pulmonary disease * Active infections * Cancer (current or treated within the past 2 years) or coagulation disorder * Rapid weight change within the past year * Physically unable to participate in the intervention * Are not currently taking, or recently (w/in 1month of participation) taken prescribed or over the counter ergogenic aids or compounds known to be banned by the NCAA. The NCAA banned substances list can be viewed from: http://www.ncaa.org/health-and-safety/policy/2014-15-ncaa-banned-drugs * Unable to complete a minimum of 85% of the assigned rehabilitation sessions.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Determine if BFR Changes Loss of LE Lean Muscle Mass | Pre-surgery, 6 weeks post-surgery and 12 weeks post-surgery | LE lean muscle mass was measured in kilograms using DEXA (iDXA, GE®) |
| Determine if BFR Changes Loss of Bone Mass | Pre-surgery, 6 weeks post-surgery and 12 weeks post-surgery | Bone mass was measured in grams using DEXA (iDXA, GE®) |
| Determine if BFR Changes Loss of Bone Mineral Density | Pre-surgery, 6 weeks post-surgery and 12 weeks post-surgery | Bone mineral density was measured in grams/cm2 using DEXA (iDXA, GE®) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | Week 8 and Week 12 post-surgery | Single leg (SL) squat (best of 3 attempts) |
Participant flow
Recruitment details
Houston hospital and clinic locations
Pre-assignment details
Examples of why a patient might be enrolled and then not assigned to a study arm would be: * new injury * deciding on a different PT location * time constraints
Participants by arm
| Arm | Count |
|---|---|
| Control - Routine Rehab Participants in this group received standard ACL rehab with no blood flow restriction therapy. | 24 |
| Experimental - BFR Participants in this group received standard ACL rehab with the addition of blood flow restriction therapy.
Blood flow restriction (BFR): The study group underwent normal ACL rehab modified by use of a tourniquet for blood flow restriction during selected exercises. | 26 |
| Total | 50 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Lost to Follow-up | 9 | 9 |
Baseline characteristics
| Characteristic | Control - Routine Rehab | Experimental - BFR | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical Between 18 and 65 years | 24 Participants | 26 Participants | 50 Participants |
| Race and Ethnicity Not Collected | — | — | 0 Participants |
| Sex: Female, Male Female | 11 Participants | 8 Participants | 19 Participants |
| Sex: Female, Male Male | 13 Participants | 18 Participants | 31 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 26 | 0 / 24 |
| other Total, other adverse events | 1 / 26 | 0 / 24 |
| serious Total, serious adverse events | 0 / 26 | 0 / 24 |
Outcome results
Primary
Determine if BFR Changes Loss of Bone Mass
Bone mass was measured in grams using DEXA (iDXA, GE®)
Time frame: Pre-surgery, 6 weeks post-surgery and 12 weeks post-surgery
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Control | Determine if BFR Changes Loss of Bone Mass | Whole Limb Bone Mass at Pre-surgery | 567.9 g | Standard Deviation 6.4 |
| Control | Determine if BFR Changes Loss of Bone Mass | Whole Limb Bone Mass at 6 weeks post-operation | 555 g | Standard Deviation 6.4 |
| Control | Determine if BFR Changes Loss of Bone Mass | Whole Limb Bone Mass at 12 weeks post-operation | 550.9 g | Standard Deviation 6.4 |
| Control | Determine if BFR Changes Loss of Bone Mass | Femur Bone Mass at Pre-surgery | 156.2 g | Standard Deviation 2.5 |
| Control | Determine if BFR Changes Loss of Bone Mass | Femur Bone Mass at 6 weeks post surgery | 151.2 g | Standard Deviation 2.5 |
| Control | Determine if BFR Changes Loss of Bone Mass | Femur Bone Mass at 12 weeks post surgery | 148.9 g | Standard Deviation 1.8 |
| Experimental - BFR | Determine if BFR Changes Loss of Bone Mass | Femur Bone Mass at 6 weeks post surgery | 154.3 g | Standard Deviation 2.3 |
| Experimental - BFR | Determine if BFR Changes Loss of Bone Mass | Whole Limb Bone Mass at Pre-surgery | 568.2 g | Standard Deviation 6.1 |
| Experimental - BFR | Determine if BFR Changes Loss of Bone Mass | Femur Bone Mass at Pre-surgery | 156.4 g | Standard Deviation 2.3 |
| Experimental - BFR | Determine if BFR Changes Loss of Bone Mass | Whole Limb Bone Mass at 6 weeks post-operation | 567.2 g | Standard Deviation 6.1 |
| Experimental - BFR | Determine if BFR Changes Loss of Bone Mass | Femur Bone Mass at 12 weeks post surgery | 153 g | Standard Deviation 1.7 |
| Experimental - BFR | Determine if BFR Changes Loss of Bone Mass | Whole Limb Bone Mass at 12 weeks post-operation | 565.4 g | Standard Deviation 6.1 |
Primary
Determine if BFR Changes Loss of Bone Mineral Density
Bone mineral density was measured in grams/cm2 using DEXA (iDXA, GE®)
Time frame: Pre-surgery, 6 weeks post-surgery and 12 weeks post-surgery
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Control | Determine if BFR Changes Loss of Bone Mineral Density | Distal Femur Bone Mineral density at 6 weeks post-operation | 1.1 g/cm^2 | Standard Deviation 0.02 |
| Control | Determine if BFR Changes Loss of Bone Mineral Density | Proximal Tibia Bone Mineral density at 12 weeks post surgery | 1.35 g/cm^2 | Standard Deviation 0.03 |
| Control | Determine if BFR Changes Loss of Bone Mineral Density | Proximal Tibia Bone Mineral density at pre-surgery | 1.47 g/cm^2 | Standard Deviation 0.02 |
| Control | Determine if BFR Changes Loss of Bone Mineral Density | Proximal Fibia Bone Mineral Density at pre-surgery | 0.46 g/cm^2 | Standard Deviation 0.02 |
| Control | Determine if BFR Changes Loss of Bone Mineral Density | Distal Femur Bone Mineral density at 12 weeks post-operation | 1.1 g/cm^2 | Standard Deviation 0.02 |
| Control | Determine if BFR Changes Loss of Bone Mineral Density | Proximal Fibia Bone Mineral Density at 6 weeks post-surgery | 0.40 g/cm^2 | Standard Deviation 0.02 |
| Control | Determine if BFR Changes Loss of Bone Mineral Density | Proximal Tibia Bone Mineral density at 6 weeks post surgery | 1.40 g/cm^2 | Standard Deviation 0.02 |
| Control | Determine if BFR Changes Loss of Bone Mineral Density | Proximal Fibia Bone Mineral Density at 12 weeks post surgery | 0.38 g/cm^2 | Standard Deviation 0.02 |
| Control | Determine if BFR Changes Loss of Bone Mineral Density | Distal Femur Bone Mineral density at pre-surgery | 1.2 g/cm^2 | Standard Deviation 0.02 |
| Experimental - BFR | Determine if BFR Changes Loss of Bone Mineral Density | Proximal Fibia Bone Mineral Density at 12 weeks post surgery | 0.43 g/cm^2 | Standard Deviation 0.02 |
| Experimental - BFR | Determine if BFR Changes Loss of Bone Mineral Density | Distal Femur Bone Mineral density at pre-surgery | 1.2 g/cm^2 | Standard Deviation 0.02 |
| Experimental - BFR | Determine if BFR Changes Loss of Bone Mineral Density | Distal Femur Bone Mineral density at 6 weeks post-operation | 1.2 g/cm^2 | Standard Deviation 0.02 |
| Experimental - BFR | Determine if BFR Changes Loss of Bone Mineral Density | Distal Femur Bone Mineral density at 12 weeks post-operation | 1.1 g/cm^2 | Standard Deviation 0.02 |
| Experimental - BFR | Determine if BFR Changes Loss of Bone Mineral Density | Proximal Tibia Bone Mineral density at pre-surgery | 1.47 g/cm^2 | Standard Deviation 0.04 |
| Experimental - BFR | Determine if BFR Changes Loss of Bone Mineral Density | Proximal Tibia Bone Mineral density at 6 weeks post surgery | 1.44 g/cm^2 | Standard Deviation 0.04 |
| Experimental - BFR | Determine if BFR Changes Loss of Bone Mineral Density | Proximal Tibia Bone Mineral density at 12 weeks post surgery | 1.44 g/cm^2 | Standard Deviation 0.03 |
| Experimental - BFR | Determine if BFR Changes Loss of Bone Mineral Density | Proximal Fibia Bone Mineral Density at pre-surgery | 0.46 g/cm^2 | Standard Deviation 0.02 |
| Experimental - BFR | Determine if BFR Changes Loss of Bone Mineral Density | Proximal Fibia Bone Mineral Density at 6 weeks post-surgery | 0.42 g/cm^2 | Standard Deviation 0.02 |
Primary
Determine if BFR Changes Loss of LE Lean Muscle Mass
LE lean muscle mass was measured in kilograms using DEXA (iDXA, GE®)
Time frame: Pre-surgery, 6 weeks post-surgery and 12 weeks post-surgery
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Control | Determine if BFR Changes Loss of LE Lean Muscle Mass | Pre-Surgery Whole Limb Lean Mass | 8.97 kg | Standard Deviation 0.21 |
| Control | Determine if BFR Changes Loss of LE Lean Muscle Mass | 6 week post surgery Whole Limb Lean Mass | 8.37 kg | Standard Deviation 0.21 |
| Control | Determine if BFR Changes Loss of LE Lean Muscle Mass | 12 Week Post Surgery Whole Limb Lean Mass | 8.58 kg | Standard Deviation 0.21 |
| Control | Determine if BFR Changes Loss of LE Lean Muscle Mass | Pre-Surgery Thigh Lean Mass | 3.18 kg | Standard Deviation 0.07 |
| Control | Determine if BFR Changes Loss of LE Lean Muscle Mass | 6 week post surgery Thigh Lean Mass | 2.91 kg | Standard Deviation 0.07 |
| Control | Determine if BFR Changes Loss of LE Lean Muscle Mass | 12 week post surgery Thigh Lean Mass | 3.04 kg | Standard Deviation 0.07 |
| Experimental - BFR | Determine if BFR Changes Loss of LE Lean Muscle Mass | 6 week post surgery Thigh Lean Mass | 3.10 kg | Standard Deviation 0.06 |
| Experimental - BFR | Determine if BFR Changes Loss of LE Lean Muscle Mass | Pre-Surgery Whole Limb Lean Mass | 8.97 kg | Standard Deviation 0.2 |
| Experimental - BFR | Determine if BFR Changes Loss of LE Lean Muscle Mass | Pre-Surgery Thigh Lean Mass | 3.18 kg | Standard Deviation 0.06 |
| Experimental - BFR | Determine if BFR Changes Loss of LE Lean Muscle Mass | 6 week post surgery Whole Limb Lean Mass | 8.93 kg | Standard Deviation 0.2 |
| Experimental - BFR | Determine if BFR Changes Loss of LE Lean Muscle Mass | 12 week post surgery Thigh Lean Mass | 3.18 kg | Standard Deviation 0.06 |
| Experimental - BFR | Determine if BFR Changes Loss of LE Lean Muscle Mass | 12 Week Post Surgery Whole Limb Lean Mass | 9.04 kg | Standard Deviation 0.2 |
Secondary
Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing
SL leg press (1RM)
Time frame: 8 weeks post surgery, 12 weeks post surgery
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Control | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | SL leg press (1RM) at 8 weeks post surgery | 58.6 kg | Standard Deviation 8 |
| Control | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | SL leg press (1RM) at 12 weeks post surgery | 76.5 kg | Standard Deviation 9 |
| Experimental - BFR | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | SL leg press (1RM) at 8 weeks post surgery | 59.3 kg | Standard Deviation 10 |
| Experimental - BFR | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | SL leg press (1RM) at 12 weeks post surgery | 72.7 kg | Standard Deviation 8.7 |
Secondary
Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing
SL hamstring curl (1RM)
Time frame: 8 weeks post surgery, 12 weeks post surgery
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Control | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | SL hamstring curl (1RM) at 8 weeks post surgery | 29.9 kg | Standard Deviation 5.1 |
| Control | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | SL hamstring curl (1RM) at 12 weeks post surgery | 38.5 kg | Standard Deviation 4.5 |
| Experimental - BFR | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | SL hamstring curl (1RM) at 8 weeks post surgery | 28.2 kg | Standard Deviation 4.2 |
| Experimental - BFR | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | SL hamstring curl (1RM) at 12 weeks post surgery | 37.7 kg | Standard Deviation 4.9 |
Secondary
Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing
Single leg (SL) squat (best of 3 attempts)
Time frame: Week 8 and Week 12 post-surgery
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Control | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | SL Squat Week 8 | 34.3 cm | Standard Deviation 6.3 |
| Control | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | SL Squat Week 12 | 40.9 cm | Standard Deviation 5.4 |
| Experimental - BFR | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | SL Squat Week 8 | 33.4 cm | Standard Deviation 5.1 |
| Experimental - BFR | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | SL Squat Week 12 | 43.0 cm | Standard Deviation 5.5 |
Secondary
Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing
Y-balance anterior (best of 3 attempts)
Time frame: 8 weeks post surgery, 12 weeks post surgery
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Control | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | Y-balance anterior (best of 3 attempts) at 8 weeks post surgery | 48.7 cm | Standard Deviation 14.3 |
| Control | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | Y-balance anterior (best of 3 attempts) at 12 weeks post surgery | 55.9 cm | Standard Deviation 18.6 |
| Experimental - BFR | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | Y-balance anterior (best of 3 attempts) at 8 weeks post surgery | 50.0 cm | Standard Deviation 2.2 |
| Experimental - BFR | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | Y-balance anterior (best of 3 attempts) at 12 weeks post surgery | 62.7 cm | Standard Deviation 18 |
Secondary
Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing
SL eccentric step down (reps to fatigue or inadequate technique)
Time frame: 8 weeks post surgery, 12 weeks post surgery
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Control | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | SL eccentric step down at 8 weeks post surgery | 44.3 reps | Standard Deviation 14.7 |
| Control | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | SL eccentric step down at 12 weeks post surgery | 61.0 reps | Standard Deviation 18.6 |
| Experimental - BFR | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | SL eccentric step down at 8 weeks post surgery | 45.1 reps | Standard Deviation 13.9 |
| Experimental - BFR | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | SL eccentric step down at 12 weeks post surgery | 62.7 reps | Standard Deviation 18 |
Secondary
Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing
Y-balance posteromedial (best of 3 attempts)
Time frame: 8 weeks post surgery, 12 weeks post surgery
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Control | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | Y-balance posteromedial (best of 3 attempts) at 8 weeks post surgery | 93.3 cm | Standard Deviation 8.6 |
| Control | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | Y-balance posteromedial (best of 3 attempts) at 12 weeks post surgery | 104.4 cm | Standard Deviation 9.2 |
| Experimental - BFR | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | Y-balance posteromedial (best of 3 attempts) at 8 weeks post surgery | 93.9 cm | Standard Deviation 7.4 |
| Experimental - BFR | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | Y-balance posteromedial (best of 3 attempts) at 12 weeks post surgery | 100.0 cm | Standard Deviation 8.5 |
Secondary
Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing
Y-balance posterolateral (best of 3 attempts)
Time frame: 8 weeks post surgery, 12 weeks post surgery
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Control | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | Y-balance posterolateral (best of 3 attempts) at 8 weeks post surgery | 90.3 cm | Standard Deviation 10.3 |
| Control | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | Y-balance posterolateral (best of 3 attempts) at 12 weeks post surgery | 104.5 cm | Standard Deviation 9.2 |
| Experimental - BFR | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | Y-balance posterolateral (best of 3 attempts) at 8 weeks post surgery | 91.9 cm | Standard Deviation 4.6 |
| Experimental - BFR | Does BFR Change the Number of Exercise Repetitions in Functional Physical Therapy Testing | Y-balance posterolateral (best of 3 attempts) at 12 weeks post surgery | 99.7 cm | Standard Deviation 8.5 |