Lower Extremity Muscle Atlas
Michael L. Richardson, M.D. source University of Washington, Radiology Department

Adductor Brevis
Adductor Longus
Adductor Magnus
Biceps Femoris-Long Head
Biceps Femoris-Short Head
Extensor Digitorum Longus
Flexor Digitorum Longus
Flexor Hallucis Longus
Gastrocnemius
Gluteus Maximus
Gluteus Medius
Gluteus Minimus
Gracilis
Iliopsoas
Obturator Externus
Obturator Internus
Pectineus
Peroneus Brevis
Peroneus Longus
Peroneus Tertius
Piriformis
Plantaris
Popliteus
Quadratus Femoris
Rectus Femoris
Sartorius
Semimembranosus
Semitendinosus
Soleus
Superior Gemellus
Tensor Fascia Lata
Tibialis Anterior
Tibialis Posterior
Vastus Intermedius
Vastus Lateralis
Vastus Medialis

Iliopsoas

Origin Psoas from anterior surfaces and lower borders of transverse processes of L1 - L5 and bodies and discs of T12 - L5; Iliacus from upper 2/3 of iliac fossa of ilium, internal lip of iliac crest, lateral aspect of sacrum, ventral sacroiliac ligament, and lower portion of iliolumbar ligament Insertion Lesser trochanter Action Flex the torso and thigh with respect to each other Innervation Psoas from direct fibers of L1 - L3 of lumbar plexus; Iliacus from muscular branch of femoral nerve Arterial Supply Lumbar branch of iliopsoas branch of internal iliac artery The medical illustrations contained in this online atlas are copyrighted © 1997 by the University of Washington.