Sartorius Muscle

The sartorius is the longest muscle in the body. It is narrow and ribbon-like and stems from the iliac spine and the upper half of the notch below it. It slants across the front of the upper thigh from the side to the middle and then descends vertically to the knee. It ends in a tendon that expands to be inserted into the surface of the body of the tibia (leg bone). The sartorius flexes, abducts (moves away from the body), and rotates the thigh sideways at the hip. It also flexes the leg at the knee joint and rotates it slightly after flexing. These actions draw the lower extremities into a sitting position and place the heel of one foot on the knee of the other. This is sometimes called a "tailor's position".