The health care practitioner will have you lay on your back with your knee bent to 90 degrees and foot resting on the table. Your foot is stabilized by another person, or by the practitioner sitting on it, then slow pressure is placed on the proximal tibia. Any looseness in the joint could indicate ACL injury. The health care practitioner will have you lay on your back. The foot on the symptomatic side is lifted with the leg straight and the foot turned inward.
Pressure is applied to the outside of the knee while the knee joint is slowly bent.
ACL injury is noted if the tibia moves out of joint at 30-40 degrees of knee flexion. The ligament prevents the knee joint from anterior instability, that is, instability in the front of the joint. This injury occurs in 4 out of 1,000 people. Please read it.