2nd Order - Exam 2

Vocabulary flashcards for upper extremity and lower extremity muscles, including attachments, innervation, and main actions.

Latissimus Dorsi

Origin: Thoracolumbar aponeurosis, iliac crest, inferior angle of scapula, and lower ribs.

Insertion: Intertubercular groove of the humerus.

Action: Extends, adducts, and medially rotates the arm; assists in respiration.

Innervation: Thoracodorsal nerve.

Pectoralis Major

Origin: Clavicular head: anterior surface of the medial clavicle. Sternocostal head: anterior surface of the sternum, superior six costal cartilages, and aponeurosis of the external oblique muscle.

Insertion: Lateral lip of the intertubercular groove of the humerus.

Action: Adducts and medially rotates humerus; flexes and extends humerus.

Innervation: Lateral and medial pectoral nerves.

Pectoralis Minor

Origin: Ribs 3-5.

Insertion: Coracoid process of scapula.

Action: Stabilizes scapula by drawing it inferiorly and anteriorly against the thoracic wall.

Innervation: Medial pectoral nerve.

Subclavius

Origin: First rib.

Insertion: Inferior surface of the middle third of the clavicle.

Action: Anchors and depresses clavicle.

Innervation: Nerve to subclavius.

Serratus Anterior

Origin: External surfaces of ribs 1-8 (or 9).

Insertion: Anterior surface of vertebral border of scapula.

Action: Protracts scapula and holds it against the thoracic wall; superiorly rotates scapula.

Innervation: Long thoracic nerve.

Deltoid

Origin: Lateral third of clavicle (anterior part), acromion (middle part), and spine of scapula (posterior part).

Insertion: Deltoid tuberosity of humerus.

Action: Anterior part flexes and medially rotates arm; middle part abducts arm; posterior part extends and laterally rotates arm.

Innervation: Axillary nerve.

Supraspinatus

Origin: Supraspinous fossa of scapula.

Insertion: Greater tubercle of humerus.

Action: Initiates and assists deltoid in abduction of arm; stabilizes humeral head in glenoid cavity.

Innervation: Suprascapular nerve.

Infraspinatus

Origin: Infraspinous fossa of scapula.

Insertion: Greater tubercle of humerus.

Action: Laterally rotates arm; stabilizes humeral head in glenoid cavity.

Innervation: Suprascapular nerve.

Teres Minor

Origin: Lateral border of scapula.

Insertion: Greater tubercle of humerus.

Action: Laterally rotates arm; stabilizes humeral head in glenoid cavity.

Innervation: Axillary nerve.

Teres Major

Origin: Inferior angle of scapula.

Insertion: Intertubercular groove of humerus.

Action: Adducts, extends, and medially rotates arm.

Innervation: Lower subscapular nerve.

Subscapularis

Origin: Subscapular fossa of scapula.

Insertion: Lesser tubercle of humerus.

Action: Medially rotates arm; helps hold head of humerus in glenoid cavity.

Innervation: Upper and lower subscapular nerves.

Biceps Brachii

Origin: Short head: Coracoid process of scapula. Long head: Supraglenoid tubercle of scapula.

Insertion: Radial tuberosity and bicipital aponeurosis into deep fascia of forearm.

Action: Supinates forearm (most powerful) and flexes forearm when supine.

Innervation: Musculocutaneous nerve.

Coracobrachialis

Origin: Coracoid process of scapula.

Insertion: Medial surface of humerus (midshaft).

Action: Helps flex and adduct arm.

Innervation: Musculocutaneous nerve.

Brachialis

Origin: Anterior surface of humerus (distal half).

Insertion: Coronoid process and ulnar tuberosity of ulna.

Action: Flexes forearm in all positions.

Innervation: Musculocutaneous and radial nerves.

Triceps Brachii

Origin: Long head: Infraglenoid tubercle of scapula.

Lateral head: Posterior surface of humerus (above radial groove).

Medial head: Posterior surface of humerus (below radial groove).

Insertion: Olecranon process of ulna.

Action: Prime mover of forearm extension. Innervation: Radial nerve.

Anconeus

Origin: Lateral epicondyle of humerus.

Insertion: Olecranon process of ulna.

Action: Assists triceps in extending forearm.

Innervation: Radial nerve.

Pronator Teres

Origin: Medial epicondyle of humerus and coronoid process of ulna.

Insertion: Lateral surface of radius (midshaft).

Action: Pronates and flexes forearm.

Innervation: Median nerve.

Flexor Carpi Radialis (FCR)

Origin: Medial epicondyle of humerus.

Insertion: Base of second and third metacarpal bones.

Action: Flexes and abducts hand.

Innervation: Median nerve.

Palmaris Longus

Origin: Medial epicondyle of humerus.

Insertion: Palmar aponeurosis.

Action: Flexes hand (at wrist) and tenses palmar aponeurosis.

Innervation: Median nerve.

Flexor Carpi Ulnaris (FCU)

Origin: Medial epicondyle of humerus and olecranon and posterior surface of ulna.

Insertion: Pisiform bone, hamate bone, and base of fifth metacarpal bone.

Action: Flexes and adducts hand (at wrist).

Innervation: Ulnar nerve.

Flexor Digitorum Superficialis (FDS)

Origin: Medial epicondyle of humerus, coronoid process of ulna, and radial shaft.

Insertion: Middle phalanges of digits 2-5.

Action: Flexes middle proximal interphalangeal joints (PIP) and metacarpophalangeal joints (MCP); flexes wrist.

Innervation: Median nerve.

Flexor Digitorum Profundus (FDP)

Origin: Anterior and medial surfaces of ulna and interosseous membrane.

Insertion: Distal phalanges of digits 2-5.

Action: Flexes distal interphalangeal joints (DIP), proximal interphalangeal joints (PIP), and metacarpophalangeal joints (MCP) of digits 2-5; flexes wrist.

Innervation: Ulnar and median nerves.

Flexor Pollicis Longus (FPL)

Origin: Anterior surface of radius and interosseous membrane.

Insertion: Distal phalanx of 1st digit (thumb).

Action: Flexes phalanges of 1st digit (thumb).

Innervation: Median nerve.

Pronator Quadratus

Origin: Distal quarter of ulna and interosseous membrane.

Insertion: Distal quarter of radius.

Action: Pronates forearm.

Innervation: Median nerve.

Brachioradialis

Origin: Lateral supracondylar ridge of humerus.

Insertion: Styloid process of radius.

Action: Relatively weak flexion of forearm; maximal when forearm is in midpronated position.

Innervation: Radial nerve.

Extensor Carpi Radialis Longus (ECRL)

Origin: Lateral supracondylar ridge of humerus.

Insertion: Base of second metacarpal bone.

Action: Extends and abducts hand at the wrist joint.

Innervation: Radial nerve.

Extensor Carpi Radialis Brevis (ECRB)

Origin: Lateral epicondyle of humerus.

Insertion: Base of third metacarpal bone.

Action: Extends and abducts hand at wrist joint.

Innervation: Radial nerve.

Extensor Digitorum

Origin: Lateral epicondyle of humerus.

Insertion: Extensor expansions of digits 2-5.

Action: Extends medial four digits at metacarpophalangeal joints (MCP) and interphalangeal joints (IP).

Innervation: Radial nerve.

Extensor Digiti Minimi (EDM)

Origin: Lateral epicondyle of humerus.

Insertion: Extensor expansion of 5th digit.

Action: Extends 5th digit at metacarpophalangeal joint and at interphalangeal joint (IP).

Innervation: Radial nerve.

Extensor Carpi Ulnaris (ECU)

Origin: Lateral epicondyle of humerus and posterior surface of ulna.

Insertion: Base of fifth metacarpal bone.

Action: Extends and adducts hand.

Innervation: Radial nerve.

Supinator

Origin: Lateral epicondyle of humerus and supinator crest of ulna.

Insertion: Lateral surface of radius (proximal).

Action: Supinates forearm.

Innervation: Radial nerve.

Extensor Indicis

Origin: Posterior surface of ulna.

Insertion: Extensor expansion of 2nd digit.

Action: Extends 2nd digit (enabling its independent extension); helps extend hand at wrist.

Innervation: Radial nerve.

Abductor Pollicis Longus (APL)

Origin: Posterior surfaces of ulna and radius and interosseous membrane.

Insertion: Base of proximal phalanx of thumb.

Action: Abducts thumb.

Innervation: Radial nerve.

Extensor Pollicis Longus (EPL)

Origin: Posterior surfaces of radius and ulna and interosseous membrane.

Insertion: Distal phalanx of thumb.

Action: Extends distal interphalangeal joint (DIP) at thumb; extends metacarpophalangeal (MCP) and carpometacarpal joints.

Innervation: Radial nerve.

Extensor Pollicis Brevis (EPB)

Origin: Posterior surface of radius and interosseous membrane.

Insertion: Base of proximal phalanx of thumb.

Action: Extends metacarpophalangeal joint (MCP) of thumb; extends carpometacarpal joint.

Innervation: Radial nerve.

Abductor Pollicis Brevis

Origin: Scaphoid and trapezium tubercles and flexor retinaculum.

Insertion: Base of proximal phalanx of thumb.

Action: Abducts thumb.

Innervation: Median nerve.

Flexor Pollicis Brevis

Origin: Trapezium, trapezoid, and capitate bones (superficial head); hamate bone (deep head).

Insertion: Base of proximal phalanx of thumb.

Action: Flexes thumb.

Innervation: Median and ulnar nerves.

Opponens Pollicis

Origin: Trapezium tubercle and flexor retinaculum.

Insertion: Radial border of first metacarpal bone.

Action: To oppose thumb.

Innervation: Median nerve.

Adductor Pollicis

Origin: Oblique head: Capitate and 2nd and 3rd metacarpals. Transverse head: Palmar surface of 3rd metacarpal.

Insertion: Base of proximal phalanx of thumb.

Action: Adducts thumb.

Innervation: Ulnar nerve.

Abductor Digiti Minimi

Origin: Pisiform bone and tendon of flexor carpi ulnaris.

Insertion: Base of proximal phalanx of 5th digit.

Action: Abducts 5th digit.

Innervation: Ulnar nerve.

Flexor Digiti Minimi Brevis

Origin: Hook of hamate and flexor retinaculum.

Insertion: Base of proximal phalanx of 5th digit.

Action: Flexes proximal phalanx of 5th digit.

Innervation: Ulnar nerve.

Opponens Digiti Minimi

Origin: Hook of hamate and flexor retinaculum.

Insertion: Medial side of 5th metacarpal bone.

Action: Brings 5th digit into opposition with thumb.

Innervation: Ulnar nerve.

Lumbricals

Origin: Tendons of flexor digitorum profundus.

Insertion: Extensor expansions on digits 2-5.

Action: Flex metacarpophalangeal joints (MCP); extend interphalangeal joints (IP) of 2nd–5th digits.

Innervation: Median nerve (1 and 2) and ulnar nerve (3 and 4).

Dorsal Interossei

Origin: Adjacent sides of metacarpals.

Insertion: Proximal phalanges and extensor expansions of digits 2-4.

Action: Abduct 2nd–4th digits.

Innervation: Ulnar nerve.

Palmar Interossei

Origin: Palmar surfaces of metacarpals.

Insertion: Proximal phalanges of digits 2, 4, and 5.

Action: Adduct 2nd, 4th, and 5th digits.

Innervation: Ulnar nerve.

Gluteus Maximus

Origin: Posterior iliac crest, sacrum, coccyx, and sacrotuberous ligament.

Insertion: Gluteal tuberosity of femur and iliotibial tract.

Action: Extends hip joint (especially from flexed position) and assists in lateral rotation; fixes hip joint.

Innervation: Inferior gluteal nerve.

Gluteus Medius

Origin: External surface of ilium between anterior and posterior gluteal lines.

Insertion: Lateral surface of greater trochanter of femur.

Action: Abduct and medially rotate hip joint; keep pelvis level when ipsilateral limb is weight bearing.

Innervation: Superior gluteal nerve.

Piriformis

Origin: Anterior surface of sacrum and sacrotuberous ligament.

Insertion: Greater trochanter of femur.

Action: Laterally rotates extended hip joint and abduct hip joint when flexed; stabilize hip joint.

Innervation: Branches of anterior rami of S1 and S2.

Quadratus Femoris

Origin: Ischial tuberosity.

Insertion: Intertrochanteric crest of femur.

Action: Laterally rotates hip joint; stabilizes hip joint.

Innervation: Nerve to quadratus femoris.

Pectineus

Origin: Superior pubic ramus.

Insertion: Pectineal line of femur.

Action: Adducts and slightly flexes hip joint; assists with lateral rotation.

Innervation: Femoral nerve (usually).

Psoas Major

Origin: Transverse processes of lumbar vertebrae.

Insertion: Lesser trochanter of femur.

Action: Act conjointly in flexion of hip joint.

Innervation: Anterior rami of lumbar nerves.

Sartorius

Origin: Anterior superior iliac spine.

Insertion: Medial surface of tibia near tibial tuberosity.

Action: Flexes, abducts, and laterally rotates hip joint; flexes knee joint.

Innervation: Femoral nerve.

Rectus Femoris

Origin: Anterior inferior iliac spine and acetabular rim.

Insertion: Tibial tuberosity via patellar tendon.

Action: Extends knee joint; rectus femoris also steadies hip joint and helps iliopsoas flex hip joint.

Innervation: Femoral nerve.

Vastus Lateralis

Origin: Greater trochanter and lateral lip of linea aspera of femur.

Insertion: Tibial tuberosity via patellar tendon.

Action: Extends knee joint.

Innervation: Femoral nerve.

Vastus Medialis

Origin: Intertrochanteric line and medial lip of linea aspera of femur.

Insertion: Tibial tuberosity via patellar tendon.

Action: Extends knee joint.

Innervation: Femoral nerve.

Vastus Intermedius

Origin: Anterior and lateral surfaces of femur (proximal).

Insertion: Tibial tuberosity via patellar tendon.

Action: Extends knee joint.

Innervation: Femoral nerve.

Adductor Longus

Origin: Inferior pubic ramus.

Insertion: Linea aspera of femur (middle third).

Action: Adducts hip joint.

Innervation: Obturator nerve.

Adductor Brevis

Origin: Inferior pubic ramus.

Insertion: Pectineal line and linea aspera of femur (proximal).

Action: Adducts hip joint and, to some extent, flexes it.

Innervation: Obturator nerve.

Adductor Magnus

Origin: Inferior pubic ramus and ischial tuberosity.

Insertion: Linea aspera and adductor tubercle of femur.

Action: Adducts hip joint; flexes hip joint (Adductor part); extends hip joint (Hamstring part).

Innervation: Obturator nerve (Adductor part) and tibial part of sciatic nerve (Hamstring part).

Gracilis

Origin: Inferior pubic ramus.

Insertion: Medial surface of tibia near tibial tuberosity.

Action: Adducts hip joint; flexes knee joint, medially rotating it when flexed.

Innervation: Obturator nerve.

Obturator Externus

Origin: Obturator foramen and adjacent bony rami.

Insertion: Trochanteric fossa of femur.

Action: Laterally rotates hip joint; stabilizes hip joint.

Innervation: Obturator nerve.

Semitendinosus

Origin: Ischial tuberosity.

Insertion: Medial surface of tibia near tibial tuberosity.

Action: Extend hip joint; flex knee joint and medially rotate it when flexed.

Innervation: Tibial division of the sciatic nerve.

Semimembranosus

Origin: Ischial tuberosity.

Insertion: Medial condyle of tibia.

Action: Extend hip joint; flex knee joint and medially rotate it when flexed.

Innervation: Tibial division of the sciatic nerve.

Biceps Femoris

Origin: Long head: Ischial tuberosity. Short head: Linea aspera of femur.

Insertion: Head of fibula.

Action: Flexes knee joint and laterally rotates it when flexed; long head extends hip joint.

Innervation: Tibial division of sciatic nerve (long head) and common fibular division of sciatic nerve (short head).

Tibialis Anterior

Origin: Lateral surface of tibia (proximal two-thirds).

Insertion: Medial cuneiform and first metatarsal bone.

Action: Dorsiflexes ankle joint and inverts foot.

Innervation: Deep fibular nerve.

Extensor Digitorum Longus

Origin: Lateral condyle of tibia and anterior surface of fibula.

Insertion: Distal phalanges of digits 2-5.

Action: Extends lateral four digits and dorsiflexes ankle joint.

Innervation: Deep fibular nerve.

Extensor Hallucis Longus

Origin: Middle portion of the anterior surface of the fibula and the interosseous membrane.

Insertion: Base of the distal phalanx of the great toe.

Action: Extends great toe and dorsiflexes ankle joint.

Innervation: Deep fibular nerve.

Fibularis Tertius

Origin: Anterior surface of fibula (distal third).

Insertion: Base of fifth metatarsal bone.

Action: Dorsiflexes ankle joint and aids in eversion of foot.

Innervation: Deep fibular nerve.

Fibularis Longus

Origin: Head and lateral surface of fibula.

Insertion: Base of first metatarsal and medial cuneiform bones.

Action: Everts foot and weakly plantarflexes ankle joint.

Innervation: Superficial fibular nerve.

Fibularis Brevis

Origin: Lateral surface of fibula (distal two-thirds).

Insertion: Tuberosity of fifth metatarsal bone.

Action: Everts foot and weakly plantarflexes ankle joint.

Innervation: Superficial fibular nerve.

Gastrocnemius

Origin: Lateral and medial heads from lateral and medial condyles of femur.

Insertion: Calcaneus via calcaneal tendon.

Action: Plantarflexes ankle joint when knee joint is extended.

Innervation: Tibial nerve.

Soleus

Origin: Head and proximal shaft of fibula and medial border of tibia.

Insertion: Calcaneus via calcaneal tendon.

Action: Plantarflexes ankle joint; stabilizes ankle joint.

Innervation: Tibial nerve.

Plantaris

Origin: Lateral supracondylar ridge of femur.

Insertion: Calcaneus via calcaneal tendon.

Action: Weakly assists gastrocnemius in plantarflexing ankle joint.

Innervation: Tibial nerve.

Popliteus

Origin: Lateral condyle of femur.

Insertion: Posterior surface of tibia (proximal to soleal line).

Action: Weakly flexes knee joint and unlocks it by rotating femur on fixed tibia.

Innervation: Tibial nerve.

Flexor Hallucis Longus

Origin: Posterior surface of fibula.

Insertion: Base of distal phalanx of great toe.

Action: Flexes great toe at all joints; weakly plantarflexes ankle joint.

Innervation: Tibial nerve.

Flexor Digitorum Longus

Origin: Posterior surface of tibia.

Insertion: Distal phalanges of digits 2-5.

Action: Flexes lateral four digits; plantarflexes ankle joint; supports longitudinal arches of foot.

Innervation: Tibial nerve.

Tibialis Posterior

Origin: Interosseous membrane and adjacent borders of tibia and fibula.

Insertion: Navicular, cuneiform, and cuboid bones.

Action: Plantarflexes ankle joint; inverts foot; maintains medial longitudinal arch.

Innervation: Tibial nerve.

Abductor Hallucis

Origin: Medial tubercle of calcaneus and plantar aponeurosis.

Insertion: Base of proximal phalanx of great toe.

Action: Abducts and flexes 1st digit (great toe).

Innervation: Medial plantar nerve.

Flexor Digitorum Brevis

Origin: Medial tubercle of calcaneus and plantar aponeurosis.

Insertion: Middle phalanges of digits 2-5.

Action: Flexes lateral four digits.

Innervation: Medial plantar nerve.

Abductor Digiti Minimi

Origin: Medial tubercle of calcaneus and plantar aponeurosis.

Insertion: Base of proximal phalanx of 5th digit.

Action: Abducts and flexes little toe (5th digit).

Innervation: Lateral plantar nerve.

Flexor Hallucis Brevis

Origin: Plantar surface of cuboid and lateral cuneiform bones.

Insertion: Base of proximal phalanx of great toe.

Action: Flexes 1st digit.

Innervation: Medial plantar nerve.

Adductor Hallucis

Origin: Oblique head: Bases of metatarsals 2-4.

Transverse head: Plantar ligaments of metatarsophalangeal joints.

Insertion: Base of proximal phalanx of great toe.

Action: Traditionally said to adduct 1st digit; assists in maintaining transverse arch of foot. Innervation:

Deep branch of the lateral plantar nerve.

Flexor Digiti Minimi Brevis

Origin: Base of the 5th metatarsal.

Insertion: Base of the proximal phalanx of the 5th digit.

Action: Flexes 5th digit.

Innervation: Superficial branch of the lateral plantar nerve.

Plantar Interossei

Origin: Plantar surfaces of metatarsals.

Insertion: Proximal phalanges of digits 3–5.

Action: Adduct and flex digits 3–5.

Innervation: Lateral plantar nerve.

Dorsal Interossei

Origin: Adjacent sides of metatarsals.

Insertion: Proximal phalanges of digits 2–4.

Action: Abduct and flex digits 2–4.

Innervation: Lateral plantar nerve.