Navigation for revision ACL reconstruction

Abstract

Revision reconstruction of the anterior cruciate ligament (ACL) is becoming more frequent due to the increasing number of ACL primary reconstruction combined with the high level of activity expected by the patients. In the revision ACL reconstruction, there are many technical issues, like bone tunnel defects or incorrect tunnel placement, that influence negatively the result compared with primary procedures. Computer-aided surgery (CAS) can enable the surgeon to improve the outcome and to detect causes for failure of the primary reconstruction. The purpose of this chapter is to describe an approach to ACL revision surgery using a commercial navigation system (BLU-IGS, Orthokey LLC, Lewes, De, USA) to intra-operatively measure joint laxity, graft elongations, isometry maps, and previous tunnel placement. This technique allows to evaluate joint kinematics and laxities before performing the ACL revision, to check the placement and the isometry of the new tunnels. Further, navigated surgery allows to test in real-time the efficacy of the reconstruction and to search for any possible associated secondary laxity. Advantages of CAS are especially important for complex scenarios as ACL revision surgery, due to the improvement of the accuracy that may potentially allow to customize the surgery for each patient to reduce the failures.