A fibrocartilaginous transition forms at the tendon-bone interface during development. This tissue reduces stress concentrations at the insertion and reduces the risk for failure. During tendon-bone healing, on the other hand, a fibrocartilaginous transition does net develop. The mechanical environment likely plays a role in fibrocartilage development. We hypothesized that compressive stresses promote fibrocartilage formation while tensile stresses promote the production of aligned collagenous tissue.