QUADRICEPS ACTIVE TEST FOR PCL TEARS The Quadriceps Active Test is usually a follow-up test for the posterior sag sign. In case of a posteriorly sagged tibia, a contraction of the quadriceps will lead to an anterior translation of the tibia of 2mm or more as the patellar ligament is slightly directed anterior. In a normal knee with 90° of flexion and with a tibia sticking out anteriorly about 1cm, the patellar ligament is slightly oriented posterior and contraction of the quadriceps does not res