This case report describes the histologic incorporation of a freeze-dried Achilles tendon allograft used for arthroscopic anterior cruciate ligament (ACL) reconstruction. The patient had regained stability from the procedure but had worsening pain over the medial compartment. The patient underwent total knee arthroplasty 2.5 years after ACL reconstruction. The surgeon was able to observe the graft in situ and examine the histology of the graft tunnel interface. This interface demonstrated Sharpey's fibers.