Anatomy & Biomechanics Final- Muscles
Pectoralis major
aDuction, flexion, and medial rotation of GHJ; Medial and lateral pectoral nerves
Abductor pollicis longus
ABduct & Extend thumb (CMC joint); Radial nerve; Deep group of posterior forearm
Gluteus medius & minimus
ABduct and medially rotate thigh, stabilize trunk; Superior gluteal nerve; Gluteal region
Dorsal interosseus muscles (foot)
ABduction of digits, Flexion of MT joints, Extension of IP joints; 1 & 2→ deep branch of fibular n., 3 & 4→ deep branch of lateral plantar n.; Interosseus compartment of foot
Adductor pollicis
ADduction of thumb; Ulnar nerve; Adductor compartment of hand
Deltoid
Actions at GHJ: Anterior→ flexion and medial rotation, Middle → aBduction (after initial 15°), Posterior→ extention & lateral rotation; Axillary nerve
Teres major
Adduction and medial rotation of the arm, Extension when flexed; Lower subscapular nerve
Lumbricals (foot)
Assists flexion of MP joints and maintains extension of PIP joints; Digits 2-4→ lateral plantar n., Digit 1→ medial plantar n.; Central compartment of foot
Tibialis anterior
Dorsiflex ankle, Invert foot; Deep fibular nerve; Anterior leg
Fibularis (peroneus) longus & brevis
Evert foot and weakly plantarflex ankle joint; Superficial fibular nerve; Lateral leg
Extensor hallucis brevis
Extend MP joint of hallux; Lateral branch of deep fibular n.; Dorsal foot
Extensor pollicis longus
Extend and ABduct thumb (CMC); Radial nerve; Deep group of posterior forearm
Extensor carpi radialis longus & brevis
Extend and ABduct wrist joint; Radial nerve; Superficial group of posterior forearm
Extensor carpi ulnaris
Extend and ADduct wrist joint; Radial nerve; Superficial group of posterior forearm
Extensor digitorum
Extend digits 2-5 (MCP, PIP, DIP) & Extend wrist; Radial nerve; Superficial group of posterior forearm
Extensor digitorum longus
Extend digits 2-5 at MTP, PIP, & DIP, Dorsiflex ankle; Deep fibular nerve; Anterior leg
Extensor digitorum brevis
Extend distal IP joints of digits 2-4; Lateral branch of deep fibular n.; Dorsal foot
Triceps brachii
Extend elbow joint, Extend GHJ (long head only); Radial nerve; extensor compartment of arm
Extensor hallucis longus
Extend hallux (MTP & IP joints), Weakly dorsiflex ankle; Deep fibular nerve; Anterior leg
Quadriceps femoris (rectus femoris, vastus lateralis, vastus medialis, vastus intermedialis)
Extend knee joint, Rectus femoris flexes hip joint; Femoral nerve; Anterior compartment of thigh
Gluteus maximus
Extend thigh at hip, ABducts hip, stabilizes trunk; Inferior gluteal nerve; Gluteal region
Extensor pollicis brevis
Extend thumb (CMC, MCP, IP); Radial nerve; Deep group of posterior forearm
Adductor magnus
Extends hip joint; aDductor part→ obturator nerve, Hamstring part→ tibial nerve; Medial compartment of thigh
Latissimus dorsi
Extension & aDduction of GHJ, medial rotation; Thoracodorsal nerve
Adductor longus and brevis
aDduct hip joint; Obturator nerve; Medial compartment of thigh
Lumbricals (hand)
Flex MCP joint; Digits 2 & 3 → Median nerve, Digits 4 & 5 → Ulnar nerve; Central compartment of hand
Flexor carpi radialis
Flex and aBduct wrist joint; Median nerve; Superficial group of anterior forearm
Abductor hallicus
Flex and aBducts big toe at MP joint; Medial plantar n.; Medial foot
Flexor carpi ulnaris
Flex and aDduct wrist joint; Ulnar nerve; superficial group of anterior forearm
Flexor digitorum superficialis
Flex digits 2-5 (MCP and PIP joints); Median nerve; Superficial group of anterior forearm
Hypothenar Muscles
aBducts, flexes, and opposes digiti minimi; Ulnar n.; Hypothenar compartment of hand
Thenar Muscles
aBducts, flexes, and opposes thumb; Median n.; Thenar compartment of hand
Flexor digitorum profundus
Flex digits 2-5 (MCP, PIP, DIP joints); Lateral ½ (digits 2,3) → Median nerve, Medial ½ (digits 4, 5) → Ulnar nerve; Deep group of anterior forearm
Flexor digitorum longus
Flex digits 2-5 and plantarflex ankle joint; Tibial nerve; Deep group of posterior leg
Quadratus plantae
Flex distal IP joint of digits 2-5 (assists FDL); Lateral plantar n.; Central foot
Brachialis
Flex elbow joint; Musculocutaneous nerve; Flexor compartment
Brachioradialis
Flex elbow joint; Radial nerve; Superficial group of posterior forearm
Flexor hallicus longus
Flex hallux and weakly plantarflex ankle joint; Tibial nerve; Deep group of posterior leg
Gastrocnemius
Flex knee joint, Plantarflex ankle joint; Tibial nerve; Superficial group of posterior leg
Flexor pollicis longus
Flex thumb (MCP, IP joints); Median nerve; Deep group of anterior forearm
Sartorius
Flex, aBduct, laterally rotate hip joint, Flex knee joint; Femoral nerve; Anterior compartment of thigh
Adductor hallucis
Flexes & aDducts big toe; Lateral plantar nerve (S2, S3); Central foot
Flexor hallucis brevis
Flexes hallux at MP joint (minimally); Medial plantar n.; Medial foot
Biceps femoris
Flexes knee, extends hip, laterally rotates thigh and leg; Long head→ tibial nerve, Short head→ common fibular nerve; Posterior thigh
Semitendinosus and semimembranosus
Flexes knee, medially rotates tibia/femur, extends hip; Tibial nerve; Posterior thigh
Supraspinatus
Initial aBductor of shoulder (synergist to deltoid in GHJ abduction); Suprascapular nerve
Tibialis posterior
Invert foot and plantarflex ankle joint; Tibial nerve; Deep group of posterior leg
Trapezius
Lateral rotation, retraction, elevation of scapula; CN XI / accessory nerve
Piriformis
Laterally rotates hip; L5-S2 spinal nerves; Gluteal region
Soleus
Plantarflex ankle joint; Tibial nerve; Superficial group of posterior leg
Infraspinatus
Principal lateral rotator of GHJ; Suprascapular nerve
Pronator quadratus
Pronate forearm; Median nerve; Deep group of anterior forearm
Serratus anterior
Protracts and laterally rotates scapula, suspends scapula; Long thoracic nerve
Abductor digiti minimi
Weakly flexes & aBducts pinky toe; Lateral plantar n.; lateral foot
Biceps brachii
When forearm supinated→ flex elbow joint, When elbow flexed→ supimate forearm: Musculocutaneous nerve; Flexor compartment
Dorsal interosseus muscles (hand)
aBduction of digits 2 - 4 (DAB); Ulnar nerve; Interosseous compartment of hand
Teres minor
principal lateral rotator at GHJ; axillary n.