posterior sag test

pos·ter·i·or sag test

(pos-tēr'ē-ŏr sag test) Maneuver used to determine integrity of posterior cruciate ligament whereby the patient is in a supine position with the hips flexed at 45 degrees and knees flexed at 90 degrees. When viewed laterally, a loss of the tibial tubercle prominence is present in a posterior cruciate deficient knee when the tibia falls back or sags on the femur.