Anatomy of the Muscles of the Lower Limb

PLEASE NOTE LEGAL ADVICE: The contents are under continuing development and improvements and may contain errors of omission or fact. The official launch will be at the end of 2018. Feedback vital and always welcome at drokane at gmail.com. This is not to be used for the assessment, diagnosis or management of patients. It should not be regarded as medical advice. It is only for educational purposes. Please adhere to your local protocols. If you are unwell please seek healthcare advice from your doctor. This does not replace senior or specialist advice. If you do not accept this then please do not use the website. If you need medical advice, please consult a doctor or other appropriate medical professional. If you are a medical professional and you need advice then speak to your senior or colleagues.

Hits

Muscles of the Lower Limb - Listed Alphabetically
Muscle	Origin	Insertion	Action	Innervation	Artery	Notes
abductor digiti minimi (foot)	medial and lateral sides of the tuberosity of the calcaneus	lateral side of the base of the proximal phalanx of the 5th digit	abducts the 5th toe; flexes the metatarsophalageal joint	lateral plantar nerve	lateral plantar a.	abductor digiti minimi forms the lateral margin of the sole of the foot
abductor hallucis	medial side of the tuberosity of calcaneus	medial side of the base of the proximal phalanx of the great toe (hallux)	abducts the great toe; flexes the metatarsophalageal joint	medial plantar nerve	medial plantar a.	abductor hallucis forms the medial margin of the sole of the foot (Latin, hallex = great toe)
adductor brevis	inferior pubic ramus	pectineal line and linea aspera (deep to the pectineus and adductor longus mm.)	adducts, flexes, and medially rotates the femur	anterior division of the obturator nerve	obturator a., deep femoral a.	anterior and posterior divisions of the obturator nerve lie on the anterior and posterior surfaces of adductor brevis
adductor hallucis	oblique head: bases of metatarsals 2-4; transverse head: heads of metatarsals 3-5	lateral side of base of the proximal phalanx of the great toe	adducts the great toe (moves it toward midline of the foot; i.e.toward the 2nd digit)	deep branch of the lateral plantar nerve	plantar arterial arch	the plantar arterial arch passes superior to the oblique head of adductor hallucis (Latin, hallex = great toe)
adductor longus	medial portion of the superior pubic ramus	linea aspera of the femur	adducts, flexes, and medially rotates the femur	anterior division of the obturator nerve	obturator a., deep femoral a.	the most anterior of the adductor group of muscles
adductor magnus	ischiopubic ramus and ischial tuberosity	linea aspera of the femur; the ischiocondylar part inserts on the adductor tubercle of the femur	adducts, flexes, and medially rotates the femur; extends the femur (ischiocondylar part)	posterior division of the obturator nerve; tibial nerve (ischiocondylar part)	obturator a., deep femoral a., medial femoral circumflex a.	the ischiocondylar part of adductor magnus is a hamstring muscle by embryonic origin and action, so it is innervated by the tibial nerve
adductor minimus	lower portion of the inferior pubic ramus	gluteal ridge and upper part of the linea aspera of the femur	adducts and laterally rotates the femur	posterior division of the obturator nerve	obturator a., medial femoral circumflex a., deep femoral a.	adductor minimus m. is the uppermost fibers of the adductor magnus m.
articularis genu	anterior surface of the femur above the patellar surface	articular capsule of the knee	elevates the articular capsule of the knee joint	femoral nerve	descending genicular a.	articularis genu is formed by muscle fascicles deep to the vastus intermedius m.
biceps femoris	long head: ischial tuberosity; short head: lateral lip of the linea aspera	head of fibula and lateral condyle of the tibia	extends the thigh, flexes the leg	long head: tibial nerve; short head: common fibular (peroneal) nerve	perforating branches of the deep femoral a.	one of the "hamstring" muscles
dorsal interosseous (foot)	shafts of adjacent metatarsal bones	bases of the proximal phalanges for digit 2 (both sides) & digits 3,4 (lateral side)	abduct digits 2-4 (move these digits away from midline as defined by a plane passing through the 2nd digit); flex the metatarsophalangeal joints and extend the interphalangeal joints of those digits	deep branch of the lateral plantar nerve	dorsal metatarsal aa.	four in number; remember DAB (Dorsal interossei ABduct) and PAD (Plantar interossei ADduct), then logic can tell you where these muscles insert (Latin, inter = between + os = bone)
extensor digitorum brevis	superolateral surface of the calcaneus	extensor expansion of toes 1-4	extends toes 1-4	deep fibular (peroneal) nerve	dorsalis pedis a.	the part of the extensor digitorum brevis that goes to the great toe is called the extensor hallucis brevis m.
extensor digitorum longus	lateral condyle of the tibia, anterior surface of the fibula, lateral portion of the interosseous membrane	dorsum of the lateral 4 toes via extensor expansions (central slip inserts on base of middle phalanx, lateral slips on base of distal phalanx)	extends the metatarsophalangeal, proximal interphalangeal and distal interphalangeal joints of the lateral 4 toes	deep fibular (peroneal) nerve	anterior tibial a.	one of the muscles involved in anterior compartment syndrome
extensor hallucis brevis	superolateral surface of the calcaneus	dorsum of base of proximal phalanx of the great toe	extends the great toe	deep fibular (peroneal) nerve	dorsalis pedis a.	usually considered to be the medial-most part of the extensor digitorum brevis m. (Latin, hallex = great toe)
extensor hallucis longus	middle half of the anterior surface of the fibula and the interosseous membrane	base of the distal phalanx of the great toe	extends the metatarsophalangeal interphalangeal joints of the great toe	deep fibular (peroneal) nerve	anterior tibial a.	one of the muscles involved in anterior compartment syndrome (Latin, hallex = great toe)
fibularis (peroneus) brevis	lower one third of the lateral surface of the fibula	tuberosity of the base of the 5th metatarsal	extends (plantar flexes) and everts the foot	superficial fibular (peroneal) nerve	fibular (peroneal) a.	stress fracture of the base of the 5th metatarsal bone is a common runner's injury
fibularis (peroneus) longus	upper two/thirds of the lateral surface of the fibula	after crossing the plantar surface of the foot deep to the intrinsic muscles, it inserts on the medial cuneiform and the base of the 1st metatarsal bone	extends (plantar flexes) and everts the foot	superficial fibular (peroneal) nerve	fibular (peroneal) a.	fibularis longus lies superficial to the fibularis brevis m. in the lateral compartment of the leg
fibularis (peroneus) tertius	distal part of the anterior surface of the fibula	dorsum of the shaft of the 5th metatarsal bone	everts the foot	deep fibular (peroneal) nerve	anterior tibial a.	fibularis tertius is in the anterior compartment of the leg, not the lateral compartment (which contains fibularis longus and brevis)
flexor digiti minimi brevis (foot)	base of 5th metatarsal bone	lateral side of base of proximal phalanx of 5th digit	flexes the metatarsophalangeal joint of the 5th digit	lateral plantar nerve	lateral plantar a.	none
flexor digitorum brevis	tuberosity of the calcaneus, plantar aponeurosis, intermuscular septae	base of the middle phalanx of digits 2-5 after splitting to allow passage of the flexor digitorum longus tendons	flexes the metatarsophalangeal & proximal interphalangeal joints of digits 2-5	medial plantar nerve	medial and lateral plantar aa.	flexor digitorum brevis in the foot is equivalent to the flexor digitorum superficialis m. of the arm
flexor digitorum longus	middle half of the posterior surface of the tibia	bases of the distal phalanges of digits 2-5	flexes the metatarsophalangeal, proximal interphalangeal and distal interphalangeal joints of digits 2-5; plantar flexes the foot	tibial nerve	tibial a.	flexor digitorum longus in the leg is equivalent to the flexor digitorum profundus m. of the arm
flexor hallucis brevis	cuboid, lateral cuneiform, medial side of the first metatarsal	medial belly: medial side of proximal phalanx of the great toe; lateral belly: lateral side of the proximal phalanx of the great toe	flexes the metatarsophalangeal joint of the great toe	medial plantar nerve (lateral belly occasionally receives innervation from the lateral plantar nerve)	medial plantar a.	each tendon of insertion contains a sesamoid bone (Latin, hallex = great toe)
flexor hallucis longus	lower 2/3 of the posterior surface of the fibula	base of the distal phalanx of the great toe	flexes the metatarsophalangeal and proximal interphalangeal joints of the great toe; plantar flexes the foot	tibial nerve	fibular (peroneal) a. and tibial a.	flexor hallucis longus is very important in the "push off" part of the normal gait (Latin, hallex = great toe)
gastrocnemius	femur; medial head: above the medial femoral condyle; lateral head: above the lateral femoral condyle	dorsum of the calcaneus via the calcaneal (Achilles') tendon	flexes leg; plantar flexes foot	tibial nerve	sural aa. (from the popliteal a.), posterior tibial a.	the calcaneal tendon of the gastrocnemius and soleus is the thickest and strongest tendon in the body
gemellus, inferior	ischial tuberosity	obturator internus tendon	laterally rotates the femur	nerve to the quadratus femoris m.	inferior gluteal a.	gemellus is a Latin word that means "little twin"
gemellus, superior	ischial spine	obturator internus tendon	laterally rotates the femur	nerve to the obturator internus m.	inferior gluteal a.	gemellus is a Latin word that means "little twin"
gluteus maximus	posterior gluteal line, posterior surface of sacrum and coccyx, sacrotuberous ligament	upper fibers: iliotibial tract; lowermost fibers: gluteal tuberosity of the femur	extends the thigh; laterally rotates the femur	inferior gluteal nerve	superior and inferior gluteal aa.	gluteus maximus is a site of intramuscular injection
gluteus medius	external surface of the ilium between the posterior and anterior gluteal lines	greater trochanter of the femur	abducts the femur; medially rotates the thigh	superior gluteal nerve	superior gluteal a.	the angle at which the gluteus medius tendon approaches the greater trochanter of the femur is anterior to the axis of rotation of the thigh, resulting in medial rotation
gluteus minimus	external surface of the ilium between the anterior and inferior gluteal lines	greater trochanter of the femur	abducts the femur; medially rotates the thigh	superior gluteal nerve	superior gluteal a.	the angle at which the gluteus minimus tendon approaches the greater trochanter of the femur is anterior to the axis of rotation of the thigh, resulting in medial rotation
gracilis	pubic symphysis and the inferior pubic ramus	medial surface of the tibia (via pes anserinus)	adducts the thigh, flexes and medially rotates the thigh, flexes the leg	anterior division of the obturator nerve	obturator a.	the pes anserinus is the common insertion of the gracilis, sartorius, and semitendinosus mm. (Latin, pes anserinus = goose's foot; gracilis = slender)
iliacus	iliac fossa and iliac crest; ala of sacrum	lesser trochanter of the femur	flexes the thigh; if the thigh is fixed it flexes the pelvis on the thigh	femoral nerve	iliolumbar a.	inserts in company with the psoas major m. via the iliopsoas tendon
iliopsoas	iliac fossa; bodies and transverse processes of lumbar vertebrae	lesser trochanter of the femur	flexes the thigh; flexes and laterally bends the lumbar vertebral column	branches of the ventral primary rami of spinal nerves L2-L4; branches of the femoral nerve	iliolumbar a.	a combination of the iliacus and psoas major mm.
inferior gemellus	ischial tuberosity	obturator internus tendon	laterally rotates the femur	nerve to the quadratus femoris m.	inferior gluteal a.	Latin, gemellus = little twin
interosseous, dorsal (foot)	shafts of adjacent metatarsal bones	bases of the proximal phalanges for digit 2 (both sides) & digits 3,4 (lateral side)	abduct digits 2-4 (move these digits away from midline as defined by a plane passing through the 2nd digit); flex the metatarsophalangeal joints and extend the interphalangeal joints of those digits	deep branch of the lateral plantar nerve	dorsal metatarsal aa.	four in number; remember DAB (Dorsal interossei ABduct) and PAD (Plantar interossei ADduct), then logic can tell you where these muscles insert (Latin, inter = between + os = bone)
interosseous, plantar	base and medial side of metatarsals 3-5	bases of proximal phalanges and extensor expansions of digits 3-5	adduct digits 3-5 (move these digits toward the midline of the foot as defined by a plane through the second digit); flex the metacarpophalangeal and extend interphalangeal joints of digits 3-5	deep branch of the lateral plantar nerve	plantar metatarsal aa.	remember PAD (Plantar interossei ADduct) and DAB (Dorsal interossei ABduct), and logic will tell you where these muscles must insert (Latin, inter = between + os = bone)
lumbricals (foot)	tendons of the flexor digitorum longus	medial side of the extensor expansion of digits 2-5	flex the metatarsophalangeal joint, extend the proximal interphalangeal & distal interphalangeal joints of digits 2-5	medial (1st) lumbrical: medial plantar nerve; lateral three lumbricals: lateral plantar nerve	medial and lateral plantar aa.	the lumbricals of the foot have the same action on the toes that the lumbricals in the hand have on the fingers (Latin, lumbricus = earthworm)
obturator externus	the external surface of the obturator membrane and the superior and inferior pubic rami	trochanteric fossa of the femur	laterally rotates the thigh	obturator nerve	obturator a.	the tendon of the obturator externus m. passes inferior to the neck of the femur to reach its insertion site
obturator internus	the internal surface of the obturator membrane and margin of the obturator foramen	greater trochanter on its medial surface above the trochanteric fossa	laterally rotates and abducts the thigh	nerve to the obturator internus m.	obturator a.	the obturator internus m. leaves the pelvis by passing through the lesser sciatic foramen; the superior and inferior gemellus mm. insert on the obturator internus tendon
pectineus	pecten of the pubis	pectineal line of the femur	adducts, flexes, and medially rotates the thigh	femoral nerve and possibly the anterior division of the obturator nerve	medial femoral circumflex a.	pectineus often has a dual innervation
peroneus mm. (SEE fibularis mm.)						peroneus is the old terminology used for the fibularis mm.
piriformis	anterior surface of sacrum	upper border of greater trochanter of femur	laterally rotates and abducts thigh	ventral rami of S1-S2		piriformis leaves the pelvis by passing through the greater sciatic foramen
plantar interosseous	base and medial side of metatarsals 3-5	bases of proximal phalanges and extensor expansions of digits 3-5	adduct digits 3-5 (move these digits toward the midline of the foot as defined by the second digit),flex metatarsophalangeal and extend interphalangeal joints of digits 3-5	deep branch of the lateral plantar nerve	plantar metatarsal aa.	remember PAD (Plantar interossei ADduct) and DAB (Dorsal interossei ABduct), and logic will tell you where these muscles must insert (Latin, inter = between + os = bone)
plantaris	above the lateral femoral condyle (above the lateral head of gastrocnemius)	dorsum of the calcaneus medial to the calcaneal tendon	flexes the leg; plantar flexes the foot	tibial nerve	popliteal a.	plantaris has a long slender tendon that is equivalent to the tendon of the palmaris longus m. of the arm; its tendon is often called the "freshman nerve" because it is often misidentified by the freshman medical student
popliteus	lateral condyle of the femur	posterior surface of the tibia above soleal line	flexes and rotates the leg medially (with the foot planted, it rotates the thigh laterally)	tibial nerve	popliteal a.	has a round tendon of origin; popliteus unlocks the knee joint to initiate flexion of the leg
psoas major	bodies and transverse processes of lumbar vertebrae	lesser trochanter of femur (with iliacus) via iliopsoas tendon	flexes the thigh; flexes & laterally bends the lumbar vertebral column	branches of the ventral primary rami of spinal nerves L2-L4	subcostal a., lumbar aa.	the genitofemoral nerve pierces the anterior surface of the psoas major m. (Latin, psoas = the muscles of the loins)
psoas minor	bodies of the T12 & L1 vertebrae	iliopubic eminence at the line of junction of the ilium and the superior pubic ramus	flexes & laterally bends the lumbar vertebral column	branches of the ventral primary rams of spinal nerves L1-L2	lumbar aa.	absent in 40% of cases (Latin, psoas = the muscles of the loins)
quadratus femoris	lateral border of the ischial tuberosity	quadrate line of the femur below the intertrochanteric crest	laterally rotates the thigh	nerve to the quadratus femoris m.	inferior gluteal a.	the nerve to the quadratus femoris m. also innervates the inferior gemellus m.
quadratus plantae	anterior portion of the calcaneus and the long plantar ligament	tendons of the flexor digitorum longus m.	assists the flexor digitorum longus in flexing the toes	lateral plantar nerve	lateral plantar a.	the quadratus plantae m. changes the line of force of the flexor digitorum longus m. to bring it in line with the long axis of the foot (Latin, quadratus = square)
quadriceps femoris	anterior surface of the femur and the anterior side of the medial and lateral intermuscular septa	tibial tuberosity via the patellar ligament	extends the knee; rectus femoris flexes the thigh	femoral nerve	lateral circumflex femoral a., deep femoral a.	composed of 4 muscles: rectus femoris, vastus lateralis, vastus intermedius and vastus medialis
rectus femoris	straight head: anterior inferior iliac spine; reflected head: above the superior rim of the acetabulum	patella and tibial tuberosity (via the patellar ligament)	extends the leg, flexes the thigh	femoral nerve	lateral circumflex femoral a.	rectus femoris is part of the quadriceps femoris muscle
sartorius	anterior superior iliac spine	medial surface of the tibia (pes anserinus)	flexes, abducts and laterally rotates the thigh; flexes leg	femoral nerve	lateral femoral circumflex a., saphenous a.	its actions put the lower limb in the traditional cross-legged seated position of a tailor (Latin, sartorius = tailor)
semimembranosus	upper, outer surface of the ischial tuberosity	medial condyle of the tibia	extends the thigh, flexes the leg	tibial nerve	perforating branches of the deep femoral a.	one of the "hamstring" muscles
semitendinosus	lower, medial surface of ischial tuberosity (common tendon with biceps femoris m.)	medial surface of tibia (via pes anserinus)	extends the thigh, flexes the leg	tibial nerve	perforating branches of the deep femoral a.	pes anserinus is the common insertion for the gracilis, sartorius, and semitendinosus mm.
soleus	posterior surface of head and upper shaft of the fibula, soleal line of the tibia	dorsum of the calcaneus via the calcaneal (Achilles') tendon	plantar flexes the foot	tibial nerve	posterior tibial a.	soleus and the 2 heads of gastrocnemius are sometimes called the triceps surae muscle