Leg Flexion and Extension

Flexion of the leg is flexion at the knee. Only slight rotation can occur at the knee joint.

Muscles: sartorius, gracilis, hamstrings (semitendinosus, semimembranosus, biceps femoris), gastrocnemius, plantaris

Extension of the leg is extension at the knee. Only slight rotation can occur at the knee joint.

Muscles: quadriceps (rectus femoris, and vastus lateralis, medialis, and intermedius)