Tensor fascia lata M. function Abduction, medial rotation, and flexion of the thigh. Protects the knee joint. Tensor fascia lata M. innervation Superior gluteal N. (L4-L5) Gluteus maximus M. function Powerful extensor of hip joint. Lateral rotator. Active in rising, sitting, and climbing. Gluteus maximus M. innervation Inferior gluteal N. (L5-S2) Gluteus medius/minimus M. function Abduction, medial rotation of thigh. Keeps pelvis level when opposing leg is raised. Gluteus medius/minimus M. innervation Superior gluteal N. (L5-S1) Piriformis M. function Lateral rotator and abductor of the thigh. Keeps femur head in acetabulum. Piriformis M. innervation Sacral plexus (S1-S2) Obturator internus M. function Lateral rotator of the thigh when extended. Abductor of the thigh when flexed. Stronger than medial rotators. Controls the balance. Obturator internus M. innervation L5-S1 Superior/inferior gemellus M. function Lateral rotator of the thigh when extended. Abductor of the thigh when flexed. Stronger than medial rotators. Controls the balance. Superior gemellus M. innervation N. to Obturator int. Inferior gemellus M. innervation N. to quadratus femoris. Quadratus femoris M. function Lateral rotator of the thigh when extended. Abductor of the thigh when flexed. Stronger than medial rotators. Controls the balance. Quadratus femoris M. innervation N. to quadratus femoris Biceps femoris M. function Long head: extension at hip. Flexor and lateral rotator at knee joint. *Short head may be absent* Biceps femoris M. innervation Long head: tibial N. (L5-S2) Short head: common peroneal N. (S1-S2) Semitendineous M. function Extension at hip. Flexion and medial rotation at knee. Semitendineous M. innveration tibial N. (L5-S2) Semimembraneous M. function Hip extensor. Knee flexor. Medial rotator. Semimembraneous M. innervation tibial N. Adductor magus M. function Powerful adductor. Lateral rotator (part inserted to linea aspera) Medial rotator at knee joint. Extensor at hip joint. Adductor magnus M. innervation tibial N. to the part inserted to linea aspera obturator N. to the part inserted to adductor tubercle (puberty and conception) Adductor magnus M. Perforating arteries (3-4) usually pierce this muscle from deep femoral artery in anterior femoral region to posterior thigh region to give blood to the dorsal muscles. Adductor hiatus may be considered as the 5th hiatus, it contains the popliteal artery and vein. Plantaris M. function Best plantar flexors. Active in walking. Plantaris M., Soleus M., and Gastrocnemius M. innervation tibial N. (S1-S2) Achilles tendon (calcaneal tendon) is the most powerful tendon and important in walking. Tibialis posterior M. function Active in plantar flexion. Supination of the foot. Tibialis posterior M. innervation tibial N. (L4-L5) Flexor hallusis longus M. function Active in plantar flexion. Supination of the foot. Flexor hallusis longus M. innveration tibial N. (S1-S2) Flexor digitorum longus M.function Active in plantar flexion. Supination of the foot. Flexor digitorum longus M. innervation tibial N. (S1-S3) The tendon of tibialis posterior M., flexor hallusis longus M., and flexor digitorum longus M. pass beneath the flexor retinaculum. Popliteus M. function Flexion of the knee. Unlocking of the knee joint. Protection of lateral meniscus. Popliteus M. innervation tibial N. (L4-S1) Peroneus longus/brevis M. function Strongest pronators of the foot. Peroneus longus/brevis M. innervation superficial peroneal N. (L5-S1) What passes through the suprapiriformis hiatus? Superior gluteal vessels What passes through the infrapiriformis hiatus? Inferior gluteal vessels Internal pudendal artery and vein Pudendal N. Posterior cutaneous N. of the thigh Sciatic N. N. to obturator internus