Posterior group of thigh m Gluteus medius 愿愿 Gracilis Adductor magnus Iliotibial band Vastus lateralis Hamstring group Semimembranosus Biceps femoris Biceps femoris semitendinosus (Long head)(Short head) semimembranosus They are the main extensors of the thigh and flexors of the leg When the knee joints is semi-flexed, they can also rotate the legBiceps femoris (Long head) semitendinosus semimembranosus Biceps femoris (Short head) Posterior group of thigh m. They are the main extensors of the thigh and flexors of the leg. When the knee joints is semi-flexed, they can also rotate the leg