Ligament tensioning is a key step in Total Knee Arthroplasty surgery. The surgeon has to manually set proper tension conditions for the two lateral ligaments of the knee. Inaccuracies may lead to severe postoperative complications and, in the worst-case scenario, to revision surgery. Unfortunately, suboptimal balance conditions are unavoidable and no assistance tool has been developed up to now to help the surgeon during the surgery. The goal of this work is to propose an instrumented tibial component able to evaluate ligament balance conditions after surgery and to monitor their evolution in the postoperative period. Thanks to an embedded actuation system, optimal ligament tension values can be restored so as to improve the prosthesis lifespan and avoid the need for revision surgery.