Muscles of the Lower Limb

Muscles Of The Gluteal Region

Muscle: Coccygeus (ischiococcygeus)

Origin: Ischial spine

Insertion: Inferior end of spine

Nerve: Branches of S4 and S5 nerves

Action: Forms small part of pelvic diaphragm that supports pelvic viscera and flexes coccyx

Muscle: Gluteus maximus

Origin: Ilium; sacrum; coccyx; sacrotuberous ligament

Insertion: Gluteal tuberosity; iliotibial tract

Nerve: Inferior gluteal, L5, S1, S2

Action: Extends and rotates thigh laterally

Muscle: Gluteus medius

Origin: Ilium between iliac crest and anterior and posterior gluteal lines

Insertion: Greater trochanter

Nerve: Superior gluteal, L5, S1

Action: Abducts and rotates thigh medially; helps keep pelvis level

Muscle: Gluteus minimus

Origin: Ilium between anterior and posterior gluteal lines

Insertion: Greater trochanter

Nerve: Superior gluteal, L5, S1

Action: Abducts and rotates thigh medially; helps keep pelvis level

Muscle: Inferior gemellus

Origin: Ischial tuberosity

Insertion: Obturator internus tendon

Nerve: Nerve to quadratus femoris

Action: Rotates thigh laterally

Muscle: Obturator internus

Origin: Ischiopubic rami; obturator membrane

Insertion: Greater trochanter

Nerve: Nerve to obturator internus, L5, S1

Action: Abducts and rotates thigh laterally

Muscle: Piriformis

Origin: Pelvic surface of sacrum; sacrotuberous ligament

Insertion: Superior border of greater trochanter

Nerve: Sacral, S1, S2

Action: Rotates thigh medially

Muscle: Quadratus femoris

Origin: Ischial tuberosity

Insertion: Intertrochanteric crest

Nerve: Nerve to quadratus femoral, L5, S1

Action: Rotates thigh laterally

Anterior Muscles Of The Thigh

Muscle: Abductor

Origin: Inferior pubic ramus

Insertion: Pectineal line; uppermost linea aspera of femur

Nerve: Obturator, L2, L3, L4

Action: Adducts, flexes, rotates thigh laterally

Muscle: Abductor longus

Origin: Body of pubis below its crest

Insertion: Middle third of linea aspera of femur

Nerve: Obturator, branch of anterior division, L2, L3, L4

Action: Adducts, flexes, rotates thigh laterally

Muscle: Adductor magnus

Origin: Ischiopubic ramus; ischial tuberosity

Insertion: Linea aspera; medial supracondylar line; adductor tubercle

Nerve: Obturator, L2, L3, L4; sciatic L4

Action: Adducts, flexes, rotates, and extends thigh

Muscle: Gracilis

Origin: Body and inferior ramus of pubis

Insertion: Superior part of medial surface of tibia

Nerve: Obturator, L2, L3

Action: Adducts and flexes thigh; flexes and rotates leg medially

Muscle: Iliacus

Origin: Iliac crest, iliac fossa; ala of sacrum

Insertion: Lesser trochanter, psoas major tendon

Nerve: Femoral, L2, L4

Action: Flexes and rotates thigh medially with psoas major

Muscle: Obturator externus

Origin: Margin of obturator foramen and obturator membrane

Insertion: Trochanteric fossa of femur

Nerve: Obturator, L3, L4

Action: Rotates thigh laterally

Muscle: Pectineus

Origin: Pectineal line of pubis

Insertion: Pectineal line of femur

Nerve: Femoral, L3, L4; obturator

Action: Adducts and flexes thigh; helps with rotation

Muscle: Rectus femoris

Origin: Anterior inferior iliac spine; ilium rim of acetabulum

Insertion: Base of patella; tibial tuberosity

Nerve: Femoral, L2, L3, L4

Action: Extends leg at knee joint; stabilizes hip; helps iliopsoas flex thigh

Muscle: Sartorius

Origin: Anterior superior iliac spine, superior part of notch inferior to it

Insertion: Upper medial side of tibia

Nerve: Femoral, L2, L3

Action: Flexes, abducts, rotates thigh at hip      laterally; flexes, rotates leg at knee joint

Muscle: Vastus intermedius

Origin: Upper shaft of femur; lower lateral intermuscular septum

Insertion: Base of patella; by patellar ligament to tibial tuberosity

Nerve: Femoral

Action: Extends leg at knee joint

Muscle: Vastus lateralis

Origin: Intertrochanteric line; greater trochanter; linea aspera; gluteal tuberosity; lateral intermuscular septum

Insertion: Lateral side of patella; tibial tuberosity

Nerve: Femoral, L2, L3, L4

Action: Extends leg at knee joint

Muscle: Vastus medialis

Origin: Intertrochanteric line; linea aspera; medial intermuscular septum

Insertion: Medial side of patella; tibial tuberosity

Nerve: Femoral, L2, L3, L4

Action: Extends leg at knee joint

Medial Muscles Of The Thigh

Muscle: Abductor brevis

Origin: Body and inferior ramus of pubis

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

Nerve: Obturator, L2, L3, L4

Action: Adducts thigh; aids in flexion

Muscle: Adductor longus

Origin: Body of pubis inferior to pubic crest

Insertion: Middle third of linea aspera of femur

Nerve: Obturator L2, L3, L4

Action: Adducts thigh

Muscle: Adductor magnus

Origin: Ischiopubic ramus; ischial tuberosity

Insertion: Linea aspera; medial supracondylar line; adductor tubercle

Nerve: Obturator and sciatic

Action: Adducts, flexes, and extends thigh

Muscle: Gracilis

Origin: Body of inferior pubic of ramus

Insertion: Superior part of medial surface of tibia

Nerve: Obturator, L2, L3

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

Muscle: Obturator externus

Origin: Margin of obturator foramen and obturator membrane

Insertion: Trochanteric fossa of femur

Nerve: Obturator, L3, L4

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

Muscle: Pectineus

Origin: Pectineal line of pubis

Insertion: Pectineal line of femur

Nerve: Femoral L2 and L3; branch of obturator

Action: Adducts and flexes thigh; aids in medial rotation of thigh

Posterior Muscles Of The Thigh

Muscle: Biceps femoris

Origin: Long head from ischial tuberosity; short head from linea aspera and upper supracondylar line

Insertion: Lateral side of head of fibula; tendon split here by fibular collateral ligament of knee

Nerve: Tibial (long head), common peroneal; division of sciatic nerve, L5, S1, S2

Action: Flexes leg medially; extends thigh

Muscle: Semimembranosus

Origin: Ischial tuberosity

Insertion: Medial condyle of tibia

Nerve: Tibial portion of sciatic, L5, S1, S2

Action: Extends thigh; rotates leg medially; helps raise trunk of body against gravity

Muscle: Semitendinosus

Origin: Ischial tuberosity

Insertion: Medial surface of superior part of tibia

Nerve: Tibial division of sciatic nerve, L5, S1, S2

Action: Extends thigh; flexes leg; rotates knee medially when flexed

Muscles Of The Anterior Leg

Muscle: Articularis genus

Origin: Distal portion of anterior aspect of shaft of femur

Insertion: Synovial membrane of suprapatellar bursa of knee joint

Nerve: Femoral, L2-L4

Action: Retracts synovial membrane during extension of the knee

Muscle: Extensor digitorum longus

Origin: Lateral tibial condyle; upper two-thirds of fibula

Insertion: Bases of middle and distal phalanges

Nerve: Deep peroneal, L5, S1

Action: Extends great toe and dorsiflexes ankle

Muscle: Extensor hallucis longus

Origin: Middle half of anterior surface of fibula; interosseous membrane

Insertion: Base of distal phalanx of great toe

Nerve: Deep peroneal, L5, S1

Action: Extends great toe; dorsiflexes and inverts foot

Muscle: Peroneus tertius

Origin: Distal one-third of fibula; interosseous membrane

Insertion: Base of fifth metatarsal

Nerve: Deep peroneal

Action: Dorsiflexes and inverts foot

Muscle: Tibialis anterior

Origin: Lateral tibial condyle; interosseous membrane

Insertion: First cuneiform; first metatarsal

Nerve: Deep peroneal, L4, L5

Action: Dorsiflexes and inverts foot

Muscles Of The Lateral Leg

Muscle: Peroneus brevis

Origin: Lower lateral side of fibula; interosseous membrane

Insertion: Base of fifth metatarsal

Nerve: Superficial peroneal

Action: Everts and plantar flexes foot

Muscle: Peroneus longus

Origin: Lateral tibial condyle; head and upper lateral side of fibula

Insertion: Base of first metatarsal;        medial cuneiform

Nerve: Superficial peroneal

Action: Everts and plantar flexes foot

POSTERIOR MUSCLES OF THE LEG: SUPERFICIAL GROUP

Muscle: Gastrocnemius

Origin: Lateral (head) and medial (head) femoral condyle

Insertion: Posterior aspect of calcaneus via tendo calcaneus

Nerve: Tibial, S1, S2

Action: Flexes knee; plantar flexes ankle when knee extended

Muscle: Plantaris

Origin: Lower lateral supracondylar line and oblique popliteal ligament

Insertion: Posterior surface of calcaneus

Nerve: Tibial, S1, S2

Action: Assist gastrocnemius in plantar flexing ankle and flexing knee

Muscle: Soleus

Origin: Upper fibular head; soleal line on tibia

Insertion: Posterior aspect of calcaneus via tendo calcaneus

Nerve: Tibial, S1, S2

Action: Plantar flexes foot and ankle

Posterior Muscles Of The Leg: Deep Group

Muscle: Flexor digitorum longus

Origin: Medial portion of posterior surface of tibia        inferior to soleal line

Insertion: Base of distal phalanges of lateral four digits

Nerve: Tibial, S2, S3

Action: Flexes lateral four digits; plantar flexes ankle; supports arches of foot

Muscle: Flexor hallucis longus

Origin: Inferior two-thirds of posterior surface of fibula and interior part of interosseous membrane

Insertion: Base of distal phalanx of great toe

Nerve: Tibial, S2, S3

Action: Flexes great toe at all joints; weakly plantar flexes ankle; supports medial longitudinal arches of foot

Muscle: Popliteus

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

Insertion: Posterior surface of tibia, superior to soleal line

Nerve: Tibial, L4, L5, S1

Action: Weakly flexes knee and unlocks knee

Muscle: Tibialis posterior

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

Insertion: Tuberosity of navicular cuneiform and cuboid; base of 2nd-4th metatarsals

Nerve: Tibial, L4, L5

Action: Plantar flexes ankle; inverts foot

Muscles Of The Dorsum Of The Foot

Muscle: Extensor digitorum brevis

Origin: Dorsal surface of calcaneus

Insertion: Lateral side of long extensor tendons with slips to proximal phalanges 2nd-4th toes

Nerve: Deep peroneal, L5, S1

Action: Assists in extending middle three toes

Muscle: Extensor hallucis brevis

Origin: Dorsal surface of calcaneus

Insertion: Base of proximal phalanx of great toe

Nerve: Deep peroneal, L5, S1

Action: Extends great toe

Muscles Of The Sole Of The Foot

Muscle: Abductor digiti minimi

Origin: Medial and lateral tubercles of calcaneus, plantar aponeurosis and intermuscular septa

Insertion: Lateral side of base of proximal phalanx of fifth digit

Nerve: Lateral plantar, S2, S3

Action: Abducts and flexes fifth digit

Muscle: Abductor hallucis

Origin: Medial tubercle of calcaneus; flexor retinaculum and plantar aponeurosis

Insertion: Medial side of base of proximal phalanx of first digit

Nerve: Medial plantar, S2, S3

Action: Abducts and flexes great toe

Muscle: Adductor hallucis; oblique head

Origin: Base of metatarsals 2-4

Insertion: Proximal phalanx of great toe

Nerve: Deep branch of lateral plantar, S2, S3

Action: Adducts great toe; assists in maintaining transverse arch

Muscle: Adductor hallucis; transverse head

Origin: Capsule of lateral four metatarsophalangeal joints

Insertion: Tendon of head attached to lateral sides of base of proximal phalanx of first digit

Nerve: Deep branch of plantar, S2, S3

Action: Adducts great toe; assists in maintaining transverse arch

Muscle: Dorsal interossei (4)

Origin: Adjacent shafts of metatarsals

Insertion: Proximal phalanges of second toe medial and lateral sides; third and fourth toes lateral sides

Nerve: Lateral plantar, S2, S3

Action: Abducts toes; flexes and extends proximal and distal phalanges

Muscle: Flexor digitorum brevis

Origin: Medial tubercle of calcaneus, plantar aponeurosis and intermuscular septa

Insertion: Middle phalanges of lateral four toes

Nerve: Medial plantar, S2, S3

Action: Flexes middle phalanges of lateral four toes

Muscle: Flexor digiti minimi brevis

Origin: Base of fifth metatarsal

Insertion: Proximal phalanx of fifth toe

Nerve: Lateral plantar, S2, S3

Action: Flexes fifth toe

Muscle: Flexor hallucis brevis

Origin: Cuboid; third cuneiform

Insertion: Proximal phalanx of great toe

Nerve: Medial plantar, S2, S3

Action: Flexes great toe

Muscle: Lumbricals (4)

Origin: Tendons of flexor digitorum longus

Insertion: Proximal phalanges; extensor expansion

Nerve: First by medial plantar nerve; lateral three by lateral plantar nerve, S2, S3

Action: Flexes metatarsophalangeal joints and extends interphalangeal joints

Muscle: Plantar interossei (3)

Origin: Medial sides of metatarsals 3-5

Insertion: Medial side of base of proximal phalanges 3-5

Nerve: Lateral plantar, S2, S3

Action: Adducts toes; flexes proximal and extends distal phalanges

Muscle: Quadratus plantae

Origin: Medial and lateral side of calcaneus

Insertion: Tendons of flexor digitorum longus

Nerve: Lateral plantar, S2, S3

Action: Assists in flexing toes