Clinical test · Hips

Thomas test

A length test for the muscles at the front of the hip. Pulling one knee to the chest flattens the low back and takes it out of the equation, so the opposite thigh can only rest down as far as its own hip flexors allow. How that free leg hangs separates the deep hip flexor (iliopsoas) from the quadriceps (rectus femoris) and the tensor fasciae latae on the outside of the hip.