Muscle Anatomy: Origins, Insertions, and Actions

Gluteus maximus

origin: gluteal surface ilium, sacrum, coccyx;

insertion: gluteal tuberosity of the femur and IT tract;

action: Extends, abducts, and laterally rotates thigh;

innervation:

Gluteus medius

origin: gluteal surface of ilium;

insertion: greater trochanter of the femur;

action: Medially rotates and abducts thigh;

innervation:

Gluteus minimus

origin: gluteal surface of ilium;

insertion: greater trochanter of femur;

action: abducts thigh, medial/lateral rotation;

innervation:

Piriformis

origin: sacrum;

insertion: greater trochanter of femur;

action: Laterally rotates and abducts thigh;

innervation:

Superior gemellus

origin: ischial spine;

insertion: greater trochanter of femur;

action: Laterally rotates and transversely abducts thigh;

innervation:

Obturator internus

origin: obturator membrane;

insertion: greater trochanter of femur;

action: Laterally rotates and transversely abducts thigh;

innervation:

Inferior gemellus

origin: ischial tuberosity;

insertion: greater trochanter of femur;

action: Laterally rotates and transversely abducts thigh;

innervation:

Quadratus femoris

origin: ischial tuberosity;

insertion: femur;

action: laterally rotates thigh;

innervation:

Obturator externus

origin: obturator membrane;

insertion: trochanteric fossa of femur;

action: laterally rotates thigh;

innervation: obturator nerve

Tensor fascia latae

origin: iliac spine;

insertion: tubercle of the IT tract;

action: flexion of thigh and stabilizes knee

innervation:

Iliopsoas

origin: lumbar vertebrae, ilium;

insertion: lesser trochanter of femur;

action: flexion;

innervation:

Sartorius

origin: anterior iliac spine

insertion: tibial tuberosity

action: Flexion, lateral/medial rotation

innervation:

Adductor magnus

origin: Inferior pubic ramus, ischial ramus and tuberosity

insertion: linea aspera, medial supracondylar ridge

action: adducts and extends thigh, medial rotation;

innervation:

Adductor longus

origin: pubis;

insertion: linea aspera of femur;

action: adducts and flexes thigh, lateral rotation;

innervation:

Adductor brevis

origin: inferior pubic ramus;

insertion: linea aspera;

action: adducts and flexes thigh, lateral rotation;

innervation: obturator nerve

Gracilis

origin: inferior pubic ramus;

insertion: tibial tuberosity;

action: adducts thigh, flexes and medially rotates leg;

innervation: obturator nerve

Pectineus

origin: superior pubic ramus;

insertion: pectineal line of femur;

action: adducts and flexes thigh, lateral rotation;

innervation: femoral and obturator nerves

Semimembranosus

origin: ischial tuberosity;

insertion: medial condyle of tibia;

action: flexes and medially rotates leg; extends thigh;

innervation: sciatic nerve

Semitendinosus

origin: ischial tuberosity;

insertion: tibial tuberosity

action: Flexes and medially rotates leg; thigh extension;

innervation: sciatic nerve

Biceps femoris (long)

origin: Ischial tuberosity;

insertion: head of fibula;

action: flexes and laterally rotates leg; extends thigh;

innervation: sciatic nerve

Biceps femoris (short)

origin: Linea aspera;

insertion: head of fibula;

action: flexes and laterally rotates leg; innervation: sciatic nerve

Rectus femoris

origin: Anterior inferior iliac spine;

insertion: tibial tuberosity;

action: extends leg, flexes thigh;

innervation: femoral nerve

Vastus medialis

origin: linea aspera of femur;

insertion: tibial tuberosity;

action: extends leg;

innervation: femoral nerve

Vastus intermedius

origin: femur;

insertion: tibial tuberosity;

action: extends leg;

innervation: femoral nerve

Vastus lateralis

origin: inea aspera of femur;

insertion: tibial tuberosity;

action: extends leg;

innervation: femoral nerve

Popliteus

origin: lateral condyle of femur;

insertion: posterior surface of tibia;

action: flexes and internally rotates knee; innervation: tibial nerve

Plantaris

origin: lateral supracondylar line of femur; insertion: achilles tendon;

action: plantar flexion of foot; flexion of leg; innervation: tibial nerve

Gastrocnemius (medial)

origin: medial femoral condyles and popliteal surface of femur;

insertion: achilles tendon;

action: plantar flexes the foot; flexes leg; innervation: tibial nerve

Gastrocnemius (lateral)

origin: lateral condyle and lateral supracondylar line of the femur;

insertion: achilles tendon;

action: plantar flexion; knee flexion; innervation: tibial nerve

Tibialis anterior

origin: lateral condyle and surface of tibia, interosseous membrane;

insertion: medial cuneiform and first metatarsal;

action: extends and dorsiflexes foot;

innervation: deep fibular nerve

Extensor digitorum longus

origin: lateral condyle of tibia, fibula, interosseous membrane;

insertion: inferior phalanges 2-5, fifth metatarsal;

action: extends phalanges; dorsiflexes foot/ankle;

innervation: deep fibular nerve

Peroneus (Fibularis) tertius

origin: flexor digitorum longus tendon; insertion: fifth metatarsal;

action: dorsiflexes foot;

innervation: deep fibular nerve

Extensor Hallucis Longus

origin: fibula, interosseous membrane;

insertion: distal phalanx of big toe;

action: extends big toe and foot; dorsiflexes foot;

innervation: deep fibular nerve

fibularis longus

origin: head of fibula;

insertion: medial cuneiform, first metatarsal;

action: plantar flexes the foot;

innervation: Superficial peroneal nerve

Fibularis brevis

origin: fibula;

insertion: fifth metatarsal;

action: everts foot, plantar flexion;

innervation: superficial fibular nerve

Soleus

origin: fibula, tibia, soleal line;

insertion: calcaneus;

action: plantar flexion;

innervation: tibial nerve

Tibialis posterior

origin: tibia, soleal line, fibula;

insertion: navicular bone, cuneiform, forth metatarsal;

action: inverts and plantar flexion; innervation: tibial nerve

Flexor digitorum longus

origin: tibia;

insertion: distal phalanges;

action: flexes toes; plantar flexes foot; innervation: tibial nerve

Extensor digitorum brevis

origin: calcaneus;

insertion: extensor expansions in toes 2-4; action: extends toes 2-4;

innervation: deep peroneal nerve

Dorsal interossei

origin: metatarsal;

insertion: phalanges and extensor expansions;

action: abducts, flexes mtp joint, extends ip joints;

innervation: lateral plantar nerve

Abductor hallucis

origin: plantar aponeurosis;

insertion: proximal phalanx;

action: abducts big toe;

innervation: medial plantar nerve

Abductor digiti minimi

origin: plantar aponeurosis;

insertion: proximal phalanx;

action: abducts and flexes little toe; innervation: lateral plantar nerve

Flexor digitorum brevis

origin: plantar aponeurosis;

insertion: middle phalanges; action: flexes phalanges 2-5;

innervation: medial plantar nerve

Flexor digiti minimi longus

origin: fifth metatarsal;

insertion: proximal phalanx of little toe; action: flexion in little toe;

innervation: lateral plantar nerve

Quadratus plantae

origin: calcaneus;

insertion: flexor digitorum longus tendon; action: flexes toes 2-5;

innervation: lateral plantar nerve

Lumbricals

origin: flexor digitorum longus tendon; insertion: toe extensor expansions;

action: flexes MT joints and extends ip joints; innervation: medial plantar nerve

Adductor hallucis

origin: metatarsals, mtp joints, fibularis longus tendon, metatarsal ligament;

insertion: proximal phalanx of big toe;

action: adducts big toe; innervation: lateral plantar nerve

Plantar interossei

origin: metatarsals;

insertion: phalanges and extensor expansions;

action: adducts toes, flexes mtp joints, extends ip joints;

innervation: lateral plantar nerve

Sternocleidomastoid

origin: sternum, clavicle;

insertion: mastoid process, superior nuchal line;

action: flexes and laterally flexes neck, rotates neck;

innervation: accessory nerve

Trapezius

origin: nuchal line/ligament, spinal processes;

insertion: clavicle, acromion, spine of the scapula;

action: elevates, depresses, retracts; innervation: accessory nerve

Scalenes (anterior)

origin: transverse process of cervical vertebrae;

insertion: first rib;

action: laterally flexes neck, elevates first rib; innervation:

Scalenes (middle)

origin: transverse process of cervical vertebrae;

insertion: first rib;

action: laterally flexes neck, elevates first rib; innervation:

Scalenes (posterior)

origin: transverse process of cervical vertebrae;

insertion: second rib;

action: laterally flexes neck, elevates second rib;

innervation:

Internal Intercostals

origin: inferior borders of ribs 1-11;

insertion: superior borders of ribs;

action: depresses ribs;

innervation:

External Intercostals

origin: ;

insertion: ;

action: ;

innervation:

Rectus abdominus

origin: pubic crest and symphysis;

insertion: xiphoid process and costal cartilage;

action: flexes trunk;

innervation:

External oblique

origin: ribs;

insertion: ilium, pubis, linea albea;

action: flexes, laterally flexes trunk; innervation:

Internal oblique

origin: iliac crest;

insertion: ribs, costal cartilage;

action: flexes, laterally flexes, and rotates trunk;

innervation:

Transverse abdominus

origin: costal cartilage, iliac crest;

insertion: linea albea, pubic crest;

action: compresses abdominal structures; innervation:

Diaphragm

origin: xiphoid process, ribs, mcl/acl; insertion: central tendon;

action: inspiration;

innervation: phrenic nerves

Spinalis

origin: spinous process of thoracic/lumbar vertebrae;

insertion: spinous process of vertebrae;

action: extends and laterally flexes trunk;

innervation:

longissimus

origin: spinous process of lumbar vertebrae, sacrum, iliac crest;

insertion: transverse process of lumbar and thoracic nerves, ribs 2-12;

action: extends and laterally flexes trunk;

innervation:

iliocostalis

origin: iliac crest, sacrum;

insertion: ribs

action: extends and laterally flexes trunk;

innervation:

Quadratus lumborum

origin: iliac crest;

insertion: rib and transverse process of lumbar vertebrae;

action: extends and laterally flexes trunk;

innervation:

Flexor digiti minimi brevis

origin: ;

insertion: ;

action: ;

innervation: