Femoral nerve stretch test

Femoral nerve stretch test (Mackiewicz sign) - for the FNST the patient lies prone, the knee is passively flexed to the thigh and the hip is passively extended; the test is positive if the patient experiences anterior thigh pain. This test is usually strongly positive in patients with protrusions at L2–L3 and L3–L4, slightly positive or negative in L4–L5 disc protrusions and negative in cases with a lumbosacral protrusion.