This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This is a computational stress analysis of bone stresses after anterior cruciate ligament (ACL) reconstruction surgery. This study will examine the effect that magnitudes of graft tension on bone stresses through contact. This will help identify if contact of the graft on the bone causes bone damage and widening of the graft tunnel. Large scale computational resourses are needed for the analysis because it invovles a moving contact area between the ligament and bone.