Damage to the ACL is a common injury that usually requires surgical reconstruction to restore function and prevent progression of post-traumatic osteoarthritis. However, the reconstruction procedure frequently causes degenerative changes to the knee joint over time. The amount of tension applied to the ACL during reconstruction may indirectly affect the possible onset of arthritis over time. High tension would result in less joint motion during the initial healing stages, which may make the onset of arthritis less likely. On the other hand, high tension would result in increased compressive forces between the joint surfaces, which could lead to arthritis. The purpose of this study is to evaluate the effect of initial graft tension set during ACL reconstruction surgery on joint cartilage and the development of knee arthritis over at least a 12-year period.