THE MUSCLES OF THE UPPER AND LOWER EXTREMITIES

THE MUSCLES OF THE UPPER EXTREMITY

THE ARM

THE ANTERIOR COMPARTMENT

THE ANTERIOR COMPARTMENT OF THE ARM

THE SUPERFICIAL MUSCLES OF THE ARM (ANTERIOR VIEW)

THE DEEP MUSCLES OF THE ARM (ANTERIOR VIEW)

THE POSTERIOR COMPARTMENT

THE POSTERIOR AND LATERAL COMPARTMENTS OF THE ARM

Muscle Action

Biceps brachii - long head, short head

Flexes the forearm and the arm; supinates the forearm

Brachialis Flexes the forearm

Triceps brachii Extends the forearm and arm

Muscles of the forearm

Anconeus Extends the forearm

Brachioradialis Flexes the forearm

THE FOREARM

THE ANTERIOR GROUP

THE SUPERFICIAL ANTERIOR GROUP(LATERAL TO MEDIAL)

Muscle Action

Pronator teres Pronates the forearm

Flexor carpi radialis Flexes the wrist and adducts the hands, aids in flexion of the elbow and pronation

Plamaris longus Flexes the wrist

Flexor carpi ulnaris Flexes the wrist and adducts the hands

Flexor digitorum superficialis Flexes the wrist and phalanges

THE SUPERFICIAL ANTERIOR GROUP

Pronator teres Flexor carpi

radialis Plamaris longus Flexor carpi

ulnaris Flexor digitorum

superficialis

THE DEEP ANTERIOR GROUP(LATERAL TO MEDIAL)

Muscle Action

Flexor digitorum profundus Flexes the wrist and phalanges

Flexor pollicis longus Flexes the thumb; aids in flexing the wrist

Pronator quadratus Pronates the hands

THE DEEP ANTERIOR GROUP

Flexor digitorum profundus

Flexor pollicis longus

Pronator quadratus

THE POSTERIOR GROUP

THE SUPERFICIAL POSTERIOR GROUP(LATERAL TO MEDIAL)

Muscle Action

Extensor carpi radialis longus Extends the wrist and adducts the hand

Extensor carpi radialis brevis Extends the wrist and adducts the hand

Extensor digitorum communis Extends the fingers and the wrist

Extensor digiti minimi Extends the little finger

Extensor carpi ulnaris Extends the wrist and the hand

THE SUPERFICIAL POSTERIOR GROUP

Extensor carpi radialis longus

Extensor carpi radialis brevis

Extensor digitorum communis

Extensor digiti minimi

Extensor carpi ulnaris

THE DEEP POSTERIOR GROUP(LATERAL TO MEDIAL)

Muscle Action

Supinator Supinates the forearm

Abductor pollicis longus Abducts the thumb and the hand

Extensor pollicis brevis Extends the thumb and abducts the hand

Extensor pollicis longus Extends the thumb and abducts the hand

Extensor indicis Extends the index finger

THE DEEP POSTERIOR GROUP

Supinator Abductor pollicis

longus Extensor pollicis

brevis Extensor pollicis

longus Extensor indicis

THE MUSCLES OF THE LOWER EXTREMITY

MUSCLES THAT ACT ON THE FEMUR

Muscles Action

Iliopsoas Psoas major

Flex the thigh; flex the trunk on the femur

Gluteus maximus Exntends and laterally rorates the thigh

Gluteus medius Abducts and medially rotates the thigh

Gluteus minimus Abducts and medially rotates the thigh

Tensor fascia latae Assists in flexion, abduction, and medial rotation of the thigh

MUSCLES THAT ACT ON THE FEMUR

MUSCLES THAT ACT ON THE FEMUR

Muscle Action

Pyriformis Rotates the thigh laterally; assists in extending and abducting the thigh

Obturator internus Rotates the thigh laterally

Obturator externus Rotates the thigh laterally

Superior gemelus Rotates the thigh laterally

Inferior gemelus Rotates the thigh laterally

Quadratus femoris Rotates the thigh laterally

MEDIAL COMPARTMENT OF THE THIGH

Muscle Action

Adductor magnus Adducts and laterally rotates the thigh; assists in extending the thigh.

Adductor longus Adducts and laterally rotates the thigh; assists in extending the thigh.

Adductor brevis Adducts and laterally rotates the thigh; assists in extending the thigh.

Pectineus Adducts, flexes, and laterally rotates the thigh

Gracilis Adduct and flex the leg

ANTERIOR COMPARTMENT OF THE THIGH

Muscle Action

Sartorius Flex the thigh and the leg; laterally rotates the thigh

QUADRICEPS FEMORIS

Rectus femoris Extend the leg; flexes the thigh

Vastus lateralis Extend the leg

Vastus medialis Extend the leg

Vastus intermedius Extend the leg

POSTERIOR COMPARTMENT OF THE THIGH

Muscle Action

Hamstrings

Biceps femoris (long head and short head)

Flexes the leg; the long head extends the thigh

Semitendinosus Flexes the leg and extends the thigh

Semimembranosus Flexes the leg and extends the thigh

SUMMARY OF MUSCLE ACTIONS ON THE HIP (INCLUDING THE MUSCLES OF THE THIGH)

Flexion Extension

Iliopsoas Gluteus maximus

Sartorius Biceps femoris

Rectus femoris Semitendinosus

Pectineus Semimembranosus

Addcutor longus Piriformis

Tensor fascia latae Adductor magnus

Adduction Abduction

Adductor magnus Gluteus medius

Adductor longus Gluteus minimus

Adductor brevis Tensor fascia latae

Gracilis Piriformis

Medial rotation Lateral rotation

Gluteus medius Gluteus maximus

Gluteus minimus Piriformis

Tensor fascia latae Obturator internus

Obturator externus

Superior and inferior gemellus

Quadratus femoris

Adductor magnus

Adductor longus

Adductor brevis

Pectineus

THE LEG

ANTERIOR COMPARTMENT OF THE LEG

Muscle Action

Tibialis anterior Dorsiflexes and inverts the foot

Extensor hallucis longus (hallus = great toe)

Dorsiflexes and inverts the foot; extends the great toe

Extensor digitorum longus Dorsiflexes and everts the foot; extends the toes

Peroneus tertius Dorsiflexes and everts the toes

LATERAL COMPARTMENT OF THE LEG

Muscle Action

Peroneus longus (fibularis longus)

Plantar flexes and everts the foot

Peroneus brevis(fibularis brevis)

Plantar flexes and everts the foot

POSTERIOR COMPARTMENT OF THE LEG

Muscle Action

Superficial muscles

Gastrocnemius Flexes the leg; plantarflexes the foot

Soleus Flexes the leg

Plantaris Flexes the leg; plantarflexes the foot

Muscle Action

Deep muscles

Popliteus Flexes and medially rotates the leg

Flexor hallucis longus Plantar flexes and inverts the foot; flexes the great toe

Flexor digitorum longus Plantar flexes and inverts the foot; flexes the toes

Tibialis posterior Plantar flexes and inverts the foot

SUMMARY OF MUSCLE ACTIONS ON THE ANKLE

Dorsiflex Plantarflex

Tibialis anterior Peroneus longus

Extensor hallucis longus Peroneus brevis

Extensor digitorum longus Plantaris

Peroneus tertius Gastrocnemius

Soleus

Tibialis posterior

Flexor hallucis longus

Flexor digitorum longus

Adduction plus inversion Abduction plus eversion

Tibialis anterior Peroneus longus

Tibialis posterior Peroneus brevis

Extensor hallucis longus Peroneus tertius

Flexor hallucis longus Extensor digitorum longus

Flexor digitorum longus