Quadriceps active test to diagnose PCL tear

The quadriceps active test is used to help diagnose a PCL tear. The test is performed with the patient supine and their knee flexed to 90 degrees. While the clinician holds the foot in place against the examination table, the patient is asked to contract their quadriceps muscles. In a patient with an intact PCL, the knee does not move forward noticeably during such a contraction. In a patient with a PCL tear, the tibia shifts anteriorly with the contraction. This is because during contraction the quadriceps pull the patella, patellar tendon, and ultimately the tibial tubercle, returning the tibia back to a reduced position.