Moderated Blood Flow Restriction After Anterior Cruciate Ligament Reconstruction

The aim of this study is to determine if there is a difference in post operative rehabilitation after anterior cruciate ligament (ACL) reconstruction surgery while using moderated blood flow therapy vs. standard physical therapy. All patients undergoing ACL reconstruction, between the ages of 18-30, that consent to taking part in the study, and meet eligibility criteria, will be included in the study. Patients will be followed for two years to determine any differences in muscle strength, thigh circumference, knee range of motion, pain, functional and activity levels, patient satisfaction, levels of Human growth hormone HGH), Insulin-like Growth Factor (IGF), and Creatine Kinase (CK), KT2000, and Lachman physical examination.

The study will be a prospective, randomized, controlled trial between two treatment cohorts. A total of 50 patients will be enrolled in the study. Informed consent will be obtained in clinic prior to any surgical intervention, per the IRB protocol. Enrollees will receive a copy of the consent and HIPAA form. All patients that meet inclusion criteria who consent to participate in the study will then be randomly assigned to either the control group or moderated blood flow therapy group. Randomization will occur by autogenerated permutated 1:1 block randomization using electronic assignment from the orthopaedic research team prior to initiation of post-operative therapy. The control group will undergo standard of care, post-operative ACL reconstruction rehabilitation. The treatment group will also receive standard ACL rehabilitation combined with Delfi moderated blood flow restriction therapy. Patients will follow up at standard of care clinic visits and participate in the same standard of care physical therapy protocol for ACL reconstruction. Baseline measurements of thigh circumference, knee ROM, KT 2000, Lachman exam, and labs for HGH, IGF, and CK will be obtained preoperatively. Patients will also complete preoperative IKDC, Tegner, PROMIS, and VAS pain surveys. Measurements of thigh circumference and knee range of motion will occur at 2 week intervals post operatively. Strength testing will start at 6 weeks post-operatively. These measurements will occur during standard therapy sessions. KT 2000 and Lachman exam will be performed at 4, 6, 8, and 12 months post operatively. A standard functional return to sport evaluation will be performed at the 4, 6, 8, and 12 month postoperative visits. Labs for HGH, IGF, and CK will be drawn at 2, 6, 12, and 24 weeks. VAS pain scores will be recorded before and after each therapy session. The PROMIS, IKDC, and Tegner surveys will be given at 4, 6, 8, 12 month intervals. The study will conclude at 12 month follow up. All post-operative visits will be standard of care. No additional clinic visits will be required for this study. Background patient information will be collected including age, sex, BMI, and co-morbidities.

The control group will be necessary to provide a baseline measure on which moderated blood flow therapy will be compared.

Blinding of the subject will not be possible as the patient will be able to recognize if they have or have not had the moderated blood flow (Delfi) device applied during therapy and application of a sham-device is not practical or considered standard of care. Evaluators performing measurements will be blinded to the patient's treatment group during assessment of muscle strength, thigh circumference, knee range of motion, Lachman exam, and KT2000. Surgeons will also be blinded to the respective treatment groups. All other outcome measures are objective and quantitative.

Eligibility Criteria:
Inclusion Criteria:

* Patients between 18-30 years of age.
* Diagnosis of isolated anterior cruciate ligament (ACL) tear and pending ACL reconstruction.

Exclusion Criteria:

* age \<18 years old or \>30 years old
* Multi-ligament knee injury
* Revision ACL reconstruction
* History or peripheral vascular disease
* History of deep vein thrombosis or pulmonary embolism
* Any contraindication to moderated blood flow restriction therapy
* Inability to comply with post-operative ACL reconstruction rehabilitation
* If meniscal repair or a cartilage procedure is performed at the time of surgery that would preclude the patient from being able to follow the standard post-operative ACL rehabilitation.