Purpose: To assess for rotary instability in the knee.
Test Position: Prone.
Performing the Test: The tested knee should be placed in 30 degrees of flexion. The examiner then passively rotates the tibia medially and laterally (on the femur). Compare to the opposite extremity and to the opposite motion on the same leg.
Diagnostic Accuracy: Unknown.
Importance of Test: This test is used to recreate posterolateral instability in the knee. The position of 30 degrees flexion puts many of the rotation restricting structures on slack to allow some rotation. Should asymmetry be observed during the test, consider using other tests to determine the involved structure.
Note: these tests should only be used by properly trained health care practitioners