Testosterone Administration and ACL Reconstruction in Men

Overall Objective: The overall objective of this study is to determine if 8 weeks of
testosterone first administered 2 weeks prior to surgery, can improve the outcome of anterior
cruciate ligament (ACL) reconstruction.

Overall Hypothesis: Standard-of-care rehabilitation with the addition of testosterone
administration will augment muscle mass, strength, and physical function following ACL
reconstructive surgery compared to standard rehabilitation alone.

Significance: Muscle mass and strength are greatly reduced following ACL surgery. The
investigators hypothesize that administration of testosterone will minimize these reductions
or potentially increase muscle mass and strength. In doing so, testosterone may hasten a
patient's return to physical activity. If testosterone improves recovery after ACL surgery,
the same treatment may be used for other injuries that involve trauma and muscle atrophy.
Furthermore, this study will examine the effect of trauma with or without testosterone on
myogenic regulators in muscle tissue taken during ACL surgery—providing possible mechanistic
insights for the clinical outcomes.

Inclusion Criteria:

- A complete ACL tear as visualized on MRI

- The ACL injury can be either "isolated" or combined with one or several of the
following injuries visualized on MRI and/or arthroscopy:

- a meniscus tear that is either left untreated or treated with a partial resection

- a small, stable meniscus tear treated with fixation, but with the fixation not
interfering with the rehabilitation protocol

- cartilage changes verified on MRI with an arthroscopically determined intact surface.

- A radiographic examination with normal joint status or combined with either one of the
following findings:

- a small-avulsed fragment located laterally, usually described as a Segond fracture,
JSN grade 1 or osteophytes grade 1 as determined by the OARSI atlas15

Exclusion Criteria:

- Previous major knee injury or knee surgery

- Associated posterior cruciate ligament (PCL) or medical collateral ligament (MCL)
injury grade III

- Concomitant severe injury to contra-lateral knee

- Injury to the lateral/posterolateral ligament complex with significantly increased
laxity

- Unstable longitudinal meniscus tear that requires repair and where the following
postoperative treatment (we.e. bracing and limited range of motion) interferes with
the rehabilitation protocol

- Bi-compartmental extensive meniscus resections

- Cartilage injury representing a full thickness loss down to bone

- Total rupture of MCL/LCL as visualized on MRI.

- History of deep vein thrombosis (DVT) or a disorder of the coagulative system

- Claustrophobia

- Prior or current use of anabolic steroids

- General systemic disease affecting physical function

- Chromosomal disorders

- Medications that interfere with testosterone production or function, including but not
limited to 5α-reductase inhibitors

- Any other condition or treatment interfering with the completion of the trial