9.7: MODELS- Arm and Leg

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Name	Action	Origin	Insertion
Forearm movers
Biceps brachii	Flexes arm at elbow	Scapula	Radius
Brachialis	Flexes arm at elbow	Humerus	Ulna
Triceps brachii	Extends arm at elbow	Humerus & Scapula	Ulna
Pronator teres	Pronates forearm	Humerus & Ulna	Radius
Supinator	Supinates forearm	Humerus & Ulna	Radius
Brachioradialis	Flexes arm at elbow (beer raising)	Humerus	Radius
Hand & finger movers
Name	Action	Origin	Insertion
Flexor carpi radialis	Flexes & abducts hand at wrist	Humerus	Carpal Bones
Palmaris longus	Flexes hand at wrist	Humerus	Carpal Bones
Flexor carpi ulnaris	Flexes & adducts hand at wrist	Humerus	Carpal Bones
Extensor carpi radialis	Extends & abducts hand at wrist	Humerus	Carpal Bones
Extensor digitorum	Extends fingers	Humerus	Digits
Extensor carpi ulnaris	Extends & adducts hand at wrist	Humerus	Carpal Bones
Muscles of the thigh & leg
Name	Action	Origin	Insertion
Flexor digitorum longus	Flexes toes	Tibia	Digits
Flexor hallucis longus	Flexes hallux	Fibula	big toe
Tibialis anterior	Dorsiflex foot at ankle, inverts foot	Tibia	1st metatarsal
Extensor digitorum longus	Extends toes	Tibia & fibula	digits
Fibularis (peroneus) longus	plantarflexes	Tibia & fibula	1st metatarsal
Gastrocnemius	plantarflexes	Femur	calcaneous
Soleus	Plantarflexes	Femur & tibia	calcaneous

Name	Action	Origin	Insertion
Muscles of the leg & thigh
Psoas major	Flexes thigh at hip (also flexes vertebral column)	Thoracic and Lumbar Vertebrae	Femur
Iliacus	Flexes thigh at hip	Ilium	Femur
Adductor longus	Adducts thigh at hip	Pubis	Femur
Adductor magnus	Adducts thigh at hip	Pubis and Ischium	Femur
Gracilis	Adducts thigh at hip	Pubis	Tibia
Gluteus maximus	Extends thigh at hip, rotates thigh laterally	Ilium, Sacrum and Coccyx	Femur, ITB
Gluteus medius	Abducts thigh at hip, rotates thigh medially	Ilium	Femur
Sartorius	Flexes leg at knee (also flexes + rotates thigh at hip)	Ilium	Tibia
Tensor fascia latae	tenses the ITB, supports knee	Ilium	ITB
Iliotibial band (IT band/tract)	Not a muscle	n/a	n/a

Quadriceps femoris
Name	Action	Origin	Insertion

Rectus femoris	Extends leg at knee (also flexes thigh at hip)	Ilium	Tibia
Vastus lateralis	Extends leg at knee	Femur	Tibia
Vastus medialis	Extends leg at knee	Femur	Tibia
Vastus intermedius	Extends leg at knee	Femur	Tibia

Hamstrings
Name	Action	Origin	Insertion

Biceps femoris	Flexes leg at knee (also extends thigh at hip)	Ischium & Femur	Tibia & Fibula
Semitendinosus	Flexes leg at knee (also extends thigh at hip)	Ischium	Tibia
Semimembranosus	Flexes leg at knee (also extends thigh at hip)	Ischium	Tibia