Origin: external surfaces of 5th-12th ribs

Insertion: linea alba, pubic tubercle and anterior half of iliac crest

Action: compresses and supports abdominal viscera, flexes and rotates trunk

Innervation: Thoracoabdominal nn. (T7-T11 spinal nn.) and subcostal n.

Origin: thoracolumbar fascia, anterior 2/3 of iliac crest, and connective tissue deep to lateral 1/3 of inguinal ligament

Insertion: inferior borders of ribs 10-12, linea alba, and pecten pubis via conjoint tendon

Action: compresses and supports abdominal viscera, flexes and rotates trunk

Innervation: Thoracoabdominal nn. (anterior rami of T6-T12 spinal nn.) and first lumbar nn.

Origin: internal surfaces of 7th-12th costal cartilages, thoracolumbar fascia, iliac crest, and connective tissue deep to lateral 1/3 of inguinal ligament

Insertion: linea alba with aponeurosis of internal oblique, pubic crest, and pectin pubis via conjoint tendon

Action: Compresses and supports abdominal viscera

Innervation: Thoracoabdominal nn. (anterior rami of T6-T12 spinal nn.) and first lumbar nn.

Origin: pubic symphysis and pubic crest

Insertion: xiphoid process and 5th-7th costal cartilages

Action: flexes trunk (lumbar vertebrae) and compresses abdominal viscera; stabilizes and controls tilt of pelvis (antilordosis)

Innervation: Thoracoabdominal nn. (anterior rami of T6-T12 spinal nn.)

Origin: body of pubis; tendinous arch of obturator fascia; ischial spine

Insertion: perineal body; coccyx; anococcygeal ligament; walls of prostate or vagina, rectum, and anal canal 

Action: forms most of pelvic diaphragm that helps support pelvic viscera and resists increases in intra-abdominal pressure

Innervation: Nerve to levator ani (branches of S4), inferior anal (rectal) n., and coccygeal plexus

Origin: ischial spine

Insertion: inferior end of sacrum and coccyx

Action: forms small part of pelvic diaphragm that supports pelvic viscera; flexes coccyx 

Innervation: branches of S4 and S5 spinal nn.

Origin: pelvic surface of S2-S4 segments; superior margin of greater sciatic notch and sacrotuberous ligament

Insertion: greater trochanter of femur

Action: rotates thigh laterally; abducts thigh; assists in holding head of femur in acetabulum

Innervation: anterior rami of S1 and S2

Origin: pelvic surfaces of ilium and ischium; obturator membrane

Insertion: greater trochanter of femur

Action: rotates thigh laterally; assists in holding head of femur in acetabulum

Innervation: nerve to obturator internus (L5, S1, S2)

Origin: sides of T12-L5 vertebrae and discs between them; transverse processes of all lumbar vertebrae

Insertion: lesser trochanter of femur

Action: act conjointly in flexing thigh at hip joint and in stabilizing this joint

Innervation: anterior rami of lumbar nn. (L1, L2, L3)

Origin: sides of T12-L1 vertebrae and intervertebral discs

Insertion: pectineal line, iliopectineal eminence via iliopectineal arch

Action: act conjointly in flexing thigh at hip joint and in stabilizing this joint

Innervation: anterior rami of lumbar nn. (L1, L2)

Origin: iliac crest, iliac fossa, ala of sacrum, and anterior sacroiliac ligaments

Insertion: tendon of psoas major, lesser trochanter, and femur distal to lesser trochanter

Action: act conjointly in flexing thigh at hip joint and in stabilizing this joint

Innervation: femoral n. (L2, L3)

Origin: medial 1/2 of inferior border of 12th ribs and tops of transverse processes of lumbar vertebrae

Insertion: iliolumbar ligament and internal tip of iliac crest

Action: extends and laterally flexes vertebral column; fixes 12th rib during inspiration

Innervation: anterior branches of T12-L4 nerves

Origin: ilium posterior to posterior gluteal line; dorsal surface of sacrum and coccyx; sacrotuberous ligament

Insertion: most fibers end in IT tract, which inserts into lateral condyle of tibia; some fibers insert on gluteal tuberosity

Action: extends thigh (esp. from flexed position) and assists in its lateral rotation; steadies thigh and assists in rising from sitting position

Innervation: inferior gluteal n.

Origin: external surface of ilium between anterior and posterior gluteal lines

Insertion: lateral surface of greater trochanter of femur

Action: abduct and medially rotate thigh; keep pelvis level when ipsilateral limb is weight-bearing and advance opposite (un-supported) side during its swing phase

Innervation: superior gluteal n.

Origin: external surface of ilium between anterior and inferior gluteal lines

Insertion: anterior surface of greater trochanter of femur

Action: abduct and medially rotate thigh; keep pelvis level when ipsilateral limb is weight-bearing and advance opposite (unsupported) side during its swing phase

Innervation: superior gluteal n.

Origin: ischial spine

Insertion: medial surface of greater trochanter (trochanteric fossa) of femur

Action: laterally rotate extended thigh and abduct flexed thigh; steady femoral head in acetabulum

Innervation: nerve to obturator internus

Origin: ischial tuberosity

Insertion: medial surface of greater trochanter (trochanteric fossa) of femur

Action: laterally rotate extended thigh and abduct flexed thigh; steady femoral head in acetabulum

Innervation: nerve to quadratus femoris

Origin: lateral border of ischial tuberosity

Insertion: quadrate tubercle on intertrochanteric crest of femur and area inferior to it

Action: laterally rotates thigh; steadies femoral head in acetabulum

Innervation: nerve to quadratus femoris

Origin: anterior superior iliac spine; anterior part of iliac crest

Insertion: IT tract, which attaches to lateral condyle of tibia

Action: abduct and medially rotates thigh; keep pelvis level when ipsilateral limb is weight-bearing and advance opposite (un-supported) side during its swing phase

Innervation: superior gluteal n.

Origin: margins of obturator foramen and obturator membrane

Insertion: trochanteric fossa of femur

Action: laterally rotates thigh; steadies head of femur in acetabulum

Innervation: obturator n.

Psoas major and iliacus mm. merge at lesser trochanter of femur to form this muscle

Origin: anterior superior iliac spine and superior part of notch inferior to it

Insertion: superior part of medial surface of tibia

Action: flexes, abducts, and laterally rotates thigh at hip joint; flexes leg at knee joint (medially rotating leg when  knee is flexed)

Innervation:

Origin: anterior inferior iliac spine and ilium superior to acetabulum

Insertion: via common tendon (quadriceps tendon) and independent attachments to base of patella; indirectly via patellar ligament to tibial tuberosity

Action: extend leg at knee joint; steadies hip joint and helps iliopsoas flex thigh

Innervation: femoral n. (L2, L3, L4)

Origin: greater trochanter and lateral lip of linea aspera of femur

Insertion: via common tendon (quadriceps tendon) and independent attachments to base of patella; indirectly via patellar ligament to tibial tuberosity; attaches to tibia and patella via aponeuroses (lateral patellar retinacula)

Action: extends leg at knee joint

Innervation: femoral n. (L2, L3, L4)

Origin: anterior and lateral surfaces of shaft of femur

Insertion: via common tendon (quadriceps tendon) and independent attachments to base of patella; indirectly via patellar ligament to tibial tuberosity

Action: extends leg at knee joint

Innervation: femoral n. (L2, L3, L4)

Origin: intertrochanteric line and medial lip of linea aspera of femur

Insertion: via common tendon (quadriceps tendon) and independent attachments to base of patella; indirectly via patellar ligament to tibial tuberosity; attaches to tibia and patella via medial retinacula

Action: extends leg at knee joint

Innervation: femoral n. (L2, L3, L4)

Origin: superior ramus of pubis

Insertion: pectineal line of femur, just inferior to lesser trochanter 

Action: adducts and flexes thigh; assists with medial rotation of thigh

Innervation: femoral nerve, may receive a branch from obturator nerve

Origin: body of pubis inferior to pubic crest

Insertion: middle 1/3 of linea aspera of femur

Action: adducts thigh

Innervation: obturator n.

Origin: body and inferior ramus of pubis

Insertion: pectineal line and proximal part of linea aspera of femur

Action: adducts thigh; to some extent flexes it 

Innervation: obturator n.

Origin: inferior ramus of pubis, ramus of ischium (adductor part)

ischial tuberosity (hamstrings part)

Insertion: gluteal tuberosity, linea aspera, medial supracondylar line (adductor part)

adductor tubercle of femur (hamstring part)

Action: adducts thigh

adductor part flexes thigh

hamstring part extends thigh

Innervation: obturator n. (adductor part)

tibial part of sciatic n. (hamstring part)

Origin: body and inferior ramus of pubis

Insertion: superior part of medial surface of tibia

Action: adducts thigh; flexes leg; helps rotate leg medially

Innervation: obturator n.

Origin: ischial tuberosity (long head)

linea aspera and lateral supracondylar line of femur (short head)

Insertion: lateral side of head of fibula; tendon is split at this site by fibular collateral ligament of knee

Action: flexes leg and rotates it laterally when knee is flexed; extends thigh (e.g. accelerating mass during first step of gait)

Innervation: tibial division of sciatic n. (long head)

common fibular division of sciatic n. (short head)

Origin: ischial tuberosity

Insertion: medial surface of superior part of tibia

Action: extend thigh; flex leg and rotate it medially when knee is flexed; when thigh and leg are flexed, these muscles can extend trunk

Innervation: tibial division of sciatic n.

Origin: ischial tuberosity

Insertion: posterior part of medial condyle of tibia; reflected attachment forms oblique popliteal ligament (to lateral femoral condyle)

Action: extend thigh; flex leg and rotate it medially when knee is flexed; when thigh and leg are flexed, these muscles can extend trunk

Innervation: tibial division of sciatic n.

Origin: lateral aspect of lateral condyle of femur (lateral head)

popliteal surface of femur; superior to medial condyle (medial head)

Insertion: posterior surface of calcaneus via calcaneal tendon

Action: plantarflexes ankle when knee is extended; raises heel during walking; flexes leg at knee joint

Innervation: tibial n.

Origin: lateral surface of lateral condyle of femur and lateral meniscus

Insertion: posterior surface of tibia, superior to soleal line

Action: weakly flexes knee and unlocks it by rotating femur 5 degrees on fixed tibia; medially rotates tibia of unplanted limb

Innervation: tibial n.

Origin: lateral condyle and superior half of lateral surface of tibia and interosseous membrane

Insertion: medial and inferior surfaces of medial cuneiform and base of 1st metatarsal

Action: dorsiflexes ankle and inverts foot

Innervation: deep fibular n.

Origin: middle part of anterior surface of fibula and interosseous membrane

Insertion: dorsal aspect of base of distal phalanx of great toe (hallux)

Action: extends great toe and dorsiflexes ankle

Innervation: deep fibular n.

Origin: lateral condyle of tibia and superior 3/4 of medial surface of fibula and interosseous membrane

Insertion: middle and distal phalanges of lateral 4 digits

Action: extends lateral 4 digits and dorsiflexes ankle

Innervation: deep fibular n.

Origin: lower part of fibula

Insertion: shaft and base of 5th metatarsal

Action: dorsiflexes ankle and aids in eversion of foot

Innervation: deep fibular nerve

Origin: calcaneus (floor of tarsal sinus); interosseous talocalcaneal ligament; stem of inferior extensor retinaculum

Insertion: long extensor tendons of four medial digits (toes 2-4)

Action: aids extensor digitorum longus in extending the four medial toes at the MTP and IP joints

Innervation: deep fibular n.

Origin: calcaneus (floor of tarsal sinus); interosseous talocalcaneal ligament; stem of inferior extensor retinaculum

Insertion: dorsal aspect of base of proximal phalanx of great toe

Action: aids the extensor hallucis longus in extending the great toe at the MTP joint

Innervation: deep fibular n.

Origin: lateral side of head of fibula; lateral 2/3 of shaft of fibula

Insertion: plantar surface on opposite side of tibialis anterior insertion

Action: eversion; assist in plantar flexion

Innervation: superficial fibular nerve

Origin: inferior 2/3 of lateral surface of fibula

Insertion: tuberosity of 5th metatarsal

Action: eversion; assists in plantar flexion

Innervation: superficial fibular nerve

Origin: posterior aspect of head and superior quarter of posterior surface of fibula; soleal line and middle 1/3 of medial border of tibia; and tendinous arch extending between the bony attachments 

Insertion: posterior surface of calcaneus via calcaneal tendon

Action: plantarflexes ankle independent of position of knee; steadies leg on foot

Innervation: tibial n.

Origin: inferior end of lateral supracondylar line of femur; oblique popliteal ligament

Insertion: posterior surface of calcaneus via calcaneal tendon

Action: weakly assists gastrocnemius in plantarflexing ankle

Innervation: tibial n.

Origin: medial part of posterior surface of tibia inferior to soleal line; by a broad tendon to fibula

Insertion: bases of distal phalanges of lateral 4 digits

Action: flexes lateral 4 digits; plantarflexes ankle; supports longitudinal arches of foot

Innervation: tibial n.

Origin: inferior 2/3 of posterior surface of fibula; inferior part of interosseous membrane

Insertion: base of distal phalanx of great toe (hallux)

Action: flexes great toe at all joints; weakly plantarflexes ankle; supports medial longitudinal arch of foot

Innervation: tibial n.

Origin: interosseous membrane; posterior surface of tibia inferior to soleal line; posterior surface of fibula

Insertion: tuberosity of navicular, cuneiform, cuboid, and sustentaculum tali of calcaneus; bases of 2nd, 3rd, and 4th metatarsals

Action: plantarflexes ankle; inverts foot

Innervation:

Origin: medial tubercle of tuberosity of calcaneus; flexor retinaculum; plantar aponeurosis

Insertion: medial side of base of proximal phalanx of 1st digit

Action: abducts and flexes great toe

Innervation: medial plantar n.

Origin: medial tubercle of tuberosity of calcaneus; plantar aponeurosis; intermuscular septa

Insertion: both sides of middle phalanges of lateral 4 digits

Action: flexes lateral 4 digits

Innervation: medial plantar n.

Origin: medial and lateral tubercles of tuberosity of calcaneus; plantar aponeurosis; intermuscular septa

Insertion: lateral side of base of proximal phalanx of 5th digit

Action: abducts and flexes little toe

Innervation: lateral plantar n.

Origin: medial surface and lateral margin of plantar surface of calcaneus

Insertion: posterolateral margin of tendon of flexor digitorum longus

Action: assists flexor digitorum longus in flexing lateral four digits

Innervation: lateral plantar n.

Origin: tendons of flexor digitorum longus

Insertion: medial aspect of expansion over lateral four digits

Action: flex proximal phalanges, extend middle and distal phalanges of lateral four digits

Innervation: medial plantar n. (medial one)

lateral plantar n. (lateral three)

Origin: plantar surfaces of cuboid and lateral cuneiforms

Insertion: both sides of base of proximal phalanx of 1st digit

Action: flexes proximal phalanx of 1st digit

Innervation: medial plantar n.

Origin: base of 5th metatarsal

Insertion: base of proximal phalanx of 5th digit

Action: flexes proximal phalanx of 5th digit, thereby assisting with its flexion

Innervation: superficial branch of lateral plantar n.

Origin: bases of metatarsals 2-4 (oblique head)

plantar ligaments of MTP joints (transverse head)

Insertion: tendons of both heads attach to lateral side of base of proximal phalanx of 1st digit

Action: traditionally said to adduct 1st digit; assists in transverse arch of foot by metatarsals medially

Innervation: deep branch of lateral plantar n.

Origin: adjacent sides of metatarsals 1-5

Insertion: medial side of proximal phalanx of 2nd digit (1st)

lateral sides of 2nd-4th digits (2nd-4th)

Action: abduct digits 2-4 and flex MTP joints

Innervation: lateral plantar n.

Origin: bases and medial sides of metatarsals 3-5

Insertion: medial sides of bases of phalanges of 3rd-5th digits

Action: adduct digits (3-5) and flex MTP joints

Innervation: lateral plantar n.