The investigators wish to compare 3 methods for reconstruction of the anterior cruciate ligament using 3 different grafts: bone-patella tendon-bone, hamstrings and iliotibial tract graft, as these methods influence the muscles around the knee differently. Methods using bone-patella tendon-bone and hamstrings are performed as standard operations, and the use of the iliotibial tract graft using a new method of reconstruction.

The purpose is:

1. To assess whether one of three different grafts used for reconstruction of the ACL shows superior results compared to the others in relation to mechanical stability and re-rupture rates.
2. To assess whether one of three different methods for reconstruction of the ACL shows superior results compared to the others in subjective patient outcome measures.
3. To assess whether one of three different methods for reconstruction of the ACL shows superior results compared to the others when considering specific symptoms and complications that can be related to donor-site morbidity.
4. To assess whether one of three different methods for reconstruction of the ACL shows superior results compared to the others when considering muscular power, muscle coordination, and function.

The purpose of the study is described in the "Brief Summary" section.

Patients scheduled for ACL reconstruction at the Section of Arthroscopic Surgery and Sports Traumatology M51, Department of Orthopedics, Bispebjerg-Frederiksberg Hospital are eligible for this study Eligibility criteria are described in the "Eligibility" section.

The patients are scheduled for ACL surgery at consultation with a doctor from the Section of Arthroscopic Surgery and Sports Traumatology after usual, clinical criteria. The doctor informs the patient about the project, gives the patient the written patient information, and if the patient shows interest in the study, an appointment is scheduled with one of the surgeons involved in the project.

At this appointment the patient is informed about the project by the surgeon. The patients will be granted the reflection time they need before consenting or rejecting.

Before the day of surgery muscle power, muscle coordination and functional tests are performed, and objective tests and PROMs are completed.

Surgery is performed by one of two surgeons experienced in all three methods of surgery as described in the "Arms and Interventions" section.

After the patient is put under general anaesthesia the method of ACL reconstruction is chosen by opening a sealed envelope.

Outcome measures are recorded at 1-year and 2-year follow-up.

All three methods of reconstruction are believed to have the same risk for basic complications: infection (approx. 1%), stiffening of the knee (approx. 2%) and deep venous thrombosis (approx. 1 %)

It is assumed that a 20% difference in a patient reported outcome score (KNEES-ACL) represents a clinically relevant difference. Based on standard deviations for the outcome score, and with a 90% power, significant differences of 20 % can be shown in a sample of 20 patients. Significance level is set at 5%. The investigators aim for 30 patients in each group, considering potential drop-outs.

Inclusion Criteria:

• Patients with an ACL rupture scheduled for ACL reconstruction after clinical investigation by an orthopedic specialist at the Section of Sports Traumatology M51.
• Age 18-40 years.
• Patients able to understand given information in relation to the study and to complete out-come questionnaires.

Exclusion Criteria:

• Patient activity (sports or work) that excludes one or more of the three methods of surgery, e.g. work predominantly performed kneeling would exclude the use of the BPTBG.
• Other ligament injuries (except non-surgically treated lesion of MCL - medial collateral ligament) to the same knee or ligament injury (except non-surgically treated lesion of MCL - medial collateral ligament) to the contralateral knee
• Conditions in either knee with pain of such intensity, that participation in the functional tests of this study are impossible.
• Auto-immune disease that involves lower limb joints or muscles.
• Local or systemic infection.
• Actual or previous systemic corticosteroid, chemotherapeutic, or immunosuppressive treatment.
• BMI>30.

Yes

Outcome assessor is not involved in the surgical procedures. Participants wear long trousers at follow-up procedures to mask surgical incisions.