manœuvre de Losee

CONT: Losee's test ... is similar to the jerk test, in that the limb is moved from flexion to extension. If the left knee is being tested, the examiner stands to the left of the patient, grasps the foot with his left hand, flexes the knee to about 40° and uses his abdomen as a fulcrum to apply a valgus stress to the knee. With his right hand he increases the valgus pressure, placing the fingers on the patella and the thumb behind the fibular head ..., while simultaneously pulling the upper tibia forward. On subsequent extension, during which the lower leg may rotate inward, a lateral snapping will occur between the femur and tibia at about 20° if there is an anterior cruciate insufficiency with anterolateral rotatory instability ...