Functional Biomechanical Outcome of ACL-reconstruction vs. ACL-reconstruction and Extra-articular-tenodesis in Patients

Screening Protocol All participants that express interest in the study will receive a screening interview that will determine eligibility for participation in the study. The screening of surgical patients will be performed by one of the clinical research coordinators in the clinic of Dr. Musahl.

Potential participants who pass the screening interview will be provided a copy of the informed consent form (in person or via email). The potential participant will review the consent form in detail with a member of the clinical team in order to ensure that the participant understands the information contained in the consent form and to provide an opportunity for the participant to ask questions about the study. If the potential participant then agrees to participate, the consent form will be signed by the participant and a member of the clinical team.

Surgical Protocol Baseline testing before surgery will consist of the IKDC objective and subjective score, KOOS score, Marx activity level, Lysohm Scale and VR-12. A radiologist will grade clinical MRI for ACL, meniscus, MCL, LCL, and ALC injury. Quantitative pivot shift testing will be performed under anesthesia using the PIVOT technology and inertial sensor. Intraoperative grading of ACL injury and concomitant injuries to the articular cartilage and meniscus will be performed. If deemed eligible final randomization will occur following intraoperative grading.

Standard single bundle anatomic ACL reconstruction will be performed for all subjects. Quadrupled hamstring tendon will be used with cortical fixation on femur and tibia. ACL-R+EAT will be performed as described by Marcacci with doubled hamstring tendon left attached at the pes anserinus, an anatomic tibial tunnel, staple fixation in the over the top position, routing of the graft superficial to the LCL, and staple fixation at Gerdy's tubercle. Concomitant tears to the menisci and their roots will be repaired as indicated.

Research Scans After surgery, approximately 6 months, subjects will undergo a CT scan on bilateral knees. The CT scan will be used to create volumetric models. These bone models will be matched to the dynamic biplane x-rays. Subjects will also undergo a research MRI scan on bilateral knees. The MRI scan will be used to generate models of the knee articular cartilage.