Unit 2 Flashcards
Brachioradialis Origin
Proximal 2/3 of lateral supra-epicondylar ridge of humerus
Brachioradialis Insertion
Lateral surface of distal end of radius proximal to styloid process
Brachioradialis Innervation
Radial Nerve (C5, C6, C7)
Brachioradialis Action
Relatively weak flexion of elbow joint, maximal when forearm is in midpronated position
Extensor carpi radialis longus Origin
Lateral supra-epicondylar ridge of humerus
Extensor carpi radialis longus Insertion
Dorsal aspect of base of 2nd metacarpal
Extensor carpi radialis longus Innervation
Radial Nerve (C6, C7)
Extensor carpi radialis longus Action
Extend and abduct wrist joint
Extensor carpi radialis brevis Origin
Lateral epicondyle of humerus
Extensor carpi radialis brevis Insertion
Dorsal aspect of base of 3rd metacarpel
Extensor carpi radialis brevis Innervation
Deep branch of radial nerve (C7, C8)
Extensor carpi radialis brevis Action
Extend and abduct wrist joint; active during fist clenching
Extensor Digitorum Origin
Lateral epicondyle of humerus
Extensor Digitorum Insertion
Extensor expansions of medial four fingers
Extensor Digitorum Innervation
Posterior interosseous nerve (C7, C8), continuation of deep branch of radial nerve
Extensor Digitorum Action
Extend wrist joint; extend medial four fingres primarily at metacarpopholangeal joints, secondarily at interphalangeal joints
Extensor digiti minimi Origin
Lateral epicondyle of humerus
Extensor digiti minimi Insertion
Extensor expansion of 5th finger
Extensor digiti minimi Innervation
Posterior interosseous nerve (C7, C8), continuation of deep branch of radial nerve
Extensor digiti minimi Action
Extends wrist joint; extends 5th finger primarily at metacarpophalangeal joints, secondarily at interphalangeal joint
Extensor carpi ulnaris Origin
Lateral epicondyle of humerus; posterior border of ulna via a shared aponeurosis
Extensor carpi ulnaris Insertion
Dorsal aspect of base of 5th metacarpal
Extensor carpi ulnaris Innervation
Posterior interosseous nerve (C7, C8), continuation of deep branch of radial nerve
Extensor carpi ulnaris Action
Extends and adducts wrist joint (also active during fist clenching)
Supinator Origin
Lateral epicondyle of humerus, radial collateral and anular ligaments, supinator fossa, crest of ulna
Supinator Insertion
Lateral, posterior, and anterior surfaces of proximal third of radius
Supinator Innervation
Deep branch of radial nerve (C7, C8)
Supinator Action
Supinates forearm; rotates radius to turn palm anteriorly or superiorly (if elbow is flexed)
Abductor pollicis longus Origin
Posterior surface of proximal halves of ulna, radius, and interosseous membrane
Abductor pollicis longus Insertion
Base of 1st metacarpal
Abductor pollicis longus Innervation
Posterior interosseous nerve (C7, C8), continuation of deep branch of radial nerve
Abductor pollicis longus Action
Extends wrist joint; abducts thumb and extends it at carpometacarpal joint
Extensor pollicis longus Origin
Posterior surface of middle third of ulna and interosseous membrane
Extensor pollicis longus Insertion
Dorsal aspect of base of distal phalanx of thumb
Extensor pollicis longus Innervation
Posterior interosseous nerve (C7, C8), continuation of deep branch of radial nerve
Extensor pollicis longus Action
Extends wrist joint; extends distal phalanx of thumb at interphalangeal joint; extends metacarpophalangeal and carpometacarpal joints
Extensor pollicis brevis Origin
Posterior surface of distal third of radius and interosseous membrane
Extensor pollicis brevis Insertion
Dorsal aspect of base of proximal phalanx of thumb
Extensor pollicis brevis Innervation
Posterior interosseous nerve (C7, C8), continuation of deep branch of radial nerve
Extensor pollicis brevis Action
Extends wrist joint; extends proximal phalanx of thumb at metacarpophalangeal joint; extends carpometacarpal joint
Extensor indicis Origin
Posterior surface of distal third of ulna and interosseous membrane
Extensor indicis Insertion
Extensor expansion of 2nd finger
Extensor indicis Innervation
Posterior interosseous nerve (C7, C8), continuation of deep branch of radial nerve
Extensor indicis Action
Extends wrist joint; extends 2nd finger (enabling its independent extension); helps extend hand at wrist
Pronator Teres Origin
Ulnar head: coronoid process of ulna
Humeral head: medial epicondyle of humerus
Pronator Teres Insertion
Middle of convexity of lateral surface of radius
Pronator Teres Innervation
Median nerve (C6, C7)
Pronator Teres Action
Pronates and flexes forearm
Flexor carpi radialis Origin
Medial epicondyle of humerus
Flexor carpi radialis Insertion
Base of 2nd (3rd) metacarpal
Flexor carpi radialis Innervation
Median nerve (C6, C7)
Flexor carpi radialis Action
Flexes and abducts hand at wrist
Palmaris longus Origin
Medial epicondyle of humerus
Palmaris longus Insertion
Distal half of flexor retinaculum, palmar aponeurosis
Palmaris longus Innervation
Median nerve (C7, C8)
Palmaris longus Action
Flexes hand (at wrist) and tenses palmar aponeurosis
Flexor carpi ulnaris Origin
Ulnar head: olecranon and posterior border of ulna (via aponeurosis)
Humeral head: medial epicondyle of humerus
Flexor carpi ulnaris Insertion
Pisiform, hook of hamate, 5th metacarpal
Flexor carpi ulnaris Innervation
Ulnar nerve (C7, C8)
Flexor carpi ulnaris Action
Flexes and adducts hand at wrist
Flexor digitorum superficialis Origin
Humero-ulnar head: medial epicondyle of humerus and coronoid process of ulna
Radial head: oblique line of radius
Flexor digitorum superficialis Insertion
Shafts of middle phalanges of medial four digits
Flexor digitorum superficialis Innervation
Median nerve (C7, C8, T1)
Flexor digitorum superficialis Action
Flexes wrist joint; flexes proximal interphalangeal joints of middle four digits; acting more strongly, it also flexes proximal phalanges at metacarpophalangeal joints
Flexor digitorum profundus Origin
Proximal three quarters of medial and anterior surfaces of ulna and interosseous membrane
Flexor digitorum profundus Insertion
Bases of distal phalanges of 2nd, 3rd, 4th, and 5th digits
Flexor digitorum profundus Innervation
Lateral part (to digits 2 and 3): median nerve (C8, T1) (anterior interosseous branch) Medial part (to digits 4 and 5): ulnar nerve (C8, T1)
Flexor digitorum profundus Action
Flexes wrist joint; flexes distal interphalangeal joints of digits 2, 3, 4, and 5; assists in wrist flexion
Flexor pollicis longus Origin
Anterior surface of radius and adjacent interosseous membrane
Flexor pollicis longus Insertion
Base of distal phalanx of thumb
Flexor pollicis longus Innervation
Anterior interosseous nerve, from median nerve (C8, T1)
Flexor pollicis longus Action
Flexes wrist; flexes metacarpophalangeal and interphalangeal joints of thumb
Pronator quadratus Origin
Distal quarter of anterior surface of ulna
Pronator quadratus Insertion
Distal quarter of anterior surface of radius
Pronator quadratus Innervation
Anterior interosseous nerve, from median nerve (C8, T1)
Pronator quadratus Action
Pronates forearm; deep fibers bind radius and ulna together
Opponens pollicis Origin
Flexor retinaculum and tubercles of scaphoid and trapezium
Opponens pollicis Insertion
Lateral side of 1st metacarpal
Opponens pollicis Innervation
Recurrent branch of median nerve (C8, T1)
Opponens pollicis Action
To oppose thumb, it draws 1st metacarpal medially to cetner of palm and rotates it medially
Abductor pollicis brevis Origin
Flexor retinaculum and tubercles of scaphoid and trapzium
Abductor pollicis brevis Insertion
Lateral side of base of proximal phalanx of thumb
Abductor pollicis brevis Innervation
Recurrent branch of median nerve (C8, T1)
Abductor pollicis brevis Action
Abducts thumb; helps oppose it
Flexor pollicis brevis Origin
Flexor retinaculum and tubercles of scaphoid and trapezium
Flexor pollicis brevis Insertion
Lateral side of base of proximal phalanx of thumb
Flexor pollicis brevis Innervation
Superficial head: Recurrent branch of median nerve (C8, T1)
Deep head: Deep branch of ulnbar nerve (C8, T1)
Flexor pollicis brevis Action
Flexes thumb
Adductor pollicis Origin
Oblique head: bases of 2nd and 3rd metacarpals, capitate, adjacent carpals
Transverse head: surface of shaft of 3rd metacarpal
Adductor pollicis Insertion
Medial side of base of proximal phalanx of thumb
Adductor pollicis Innervation
Deep branch of ulnar nerve (C8, T1)
Adductor pollicis Action
Adducts thumb toward lateral border of palm
Abductor digiti minimi Origin
Pisiform
Abductor digiti minimi Insertion
Medial side of base of proximal phalanx of 5th finger
Abductor digiti minimi Innervation
Deep branch of ulnar nerve (C8, T1)
Abductor digiti minimi Action
Abducts 5th finger; assists in flexion of its proximal phalanx
Flexor digiti minimi brevis Origin
Hook of hamate and flexor retinaculum
Flexor digiti minimi brevis Insertion
Medial side of base of proximal phalanx of 5th finger
Flexor digiti minimi brevis Innervation
Deep branch of ulnar nerve (C8, T1)
Flexor digiti minimi brevis Action
Flexes proximal phalanx of 5th finger
Opponens digiti mini Origin
Hook of hamate and flexor retinaculum
Opponens digiti mini Insertion
Medial border of 5th metacarpal
Opponens digiti mini Innervation
Deep branch of ulnar nerve (C8, T1)
Opponens digiti mini Action
Draws 5th metacarpal anterior and rotates it, bringing 5th finger into opposition with thumb
Lumbricals Origin
1 and 2: lateral two tendons of flexor digitorum profundus (as unipennate muscles)
3 and 4: medial three tendons of flexor digitorum profundus (as bipenate muscles)
Lumbricals Insertion
Lateral sides of extensor expansions of 2nd–5th fingers
Lumbricals Innervation
1 and 2: Median nerve (C8, T1)
3 and 4: Deep branch of ulnar nerve (C8, T1)
Lumbricals Action
Flex metacarpophalangeal joints; extend interphalangeal joints of 2nd-5th fingers
Dorsal interossei, 1-4 Origin
Adjacent sides of 2 metacarpals (as bipennate muscles)
Dorsal interossei, 1-4 Insertion
Bases of proximal phalanges; extensor expansions of 2nd-4th fingers
Dorsal interossei, 1-4 Innervation
Deep branch of ulnar nerve (C8, T1)
Dorsal interossei, 1-4 Action
Abduct 2nd-4th fingers from axial line; act with lumbricals in flexing metacarpophalangeal joints and extending interphalangeal joints
Palmar inerossei, 1-3 Origin
Palmar surfaces of 2nd, 4th, and 5th metacarpals (as unipennate muscles)
Palmar inerossei, 1-3 Insertion
Bases of proximal phalanges; extensor expansions of 2nd, 4th, and 5th fingers
Palmar inerossei, 1-3 Innervation
Deep branch of ulnar nerve (C8, T1)
Palmar inerossei, 1-3 Action
Adduct 2nd, 4th, and 5th fingers toward axial line; assist lumbricals in flexing metacarpophalangeal joints and extend interphalangeal joints
External Intercostal Origin
Inferior border of ribs
External Intercostal Insertion
Superior border of ribs
External Intercostal Innervation
Intercostal nerve
External Intercostal Action
During forced insipiration: elevates ribs
Internal Intercostal Origin
Superior border of ribs
Internal Intercostal Insertion
Inferior border of ribs
Internal Intercostal Innervation
Intercostal nerve
Internal Intercostal Action
During forced respiration: interosseus part depresses ribs: interchondral part elevates ribs
Innermost Intercostal Origin
Inferior border of ribs
Innermost Intercostal Insertion
Superior border of ribs
Innermost Intercostal Innervation
Intercostal nerve
Innermost Intercostal Action
During forced respiration: interosseus part depresses ribs: interchondral part elevates ribs
Transversus Thoracis Origin
Posterior surface of lower sternum
Transversus Thoracis Insertion
Internal surface of costal cartilages 2-6
Transversus Thoracis Innervation
Intercostal nerve
Transversus Thoracis Action
Weakly depresses ribs
External Oblique Origin
External surfaces of 5th-12th ribs
External Oblique Insertion
Linea alba, pubic tubercle, and anterior half of illiac crest
External Oblique Innervation
Thoraco-abdominal nerves (anterior rami of T7-T11) and subcostal nerve
External Oblique Action
Compress and support abdominal viscera; flex and rotate trunk
Internal Oblique Origin
Thoracolumbar fascia, anterior two thirds of illiac crest, and connective tissue deep to inguinal ligament
Internal Oblique Insertion
Inferior borders of 10th-12th ribs, linea alba, and pubis via conjoint tendon
Internal Oblique Innervation
Thoraco-abdominal nerves (anterior rami of T7-T11), subcostal and first lumbar nerve
Internal Oblique Action
Compress and support abdominal viscera; flex and rotate trunk
Transversus Abdominis Origin
Internal surfaces of 7th-12th rcostal cartilages, thoracolumbar fascia, illiac crest, and connective tissue deep to inguinal ligament
Transversus Abdominis Insertion
Linea alba with aponeurosis of internal oblique, pubic crest, and pubis via conjoint tendon
Transversus Abdominis Innervation
Thoraco-abdominal nerves (anterior rami of T7-T11), subcostal and first lumbar nerve
Transversus Abdominis Action
Compresses and supports abdominal viscera
Rectus Abdominis Origin
Pubic symphysis and pubic crest
Rectus Abdominis Insertion
Xiphoid process of 5th-7th costal cartilages
Rectus Abdominis Innervation
Thoraco-abdominal and subcostal nerves (anterior rami of T7-T12 spinal nerves)
Rectus Abdominis Action
Flexes trunk (lumbar vertebrae) and compresses abdominal viscera, stabilizes and controls tilt of pelvis (antilordosis)
Psoas Major Origin
Transverse processes of lumbar vertebrae; sides of bodies of T12-S1 vertebrae and intervening IV discs
Psoas Major Insertion
By a strong tendon to lesser trochanter of femur
Psoas Major Innervation
Lumbar plexus via anterior branches of nerves L2-L4
Psoas Major Action
Acting inferiorly with iliacus, flexes thigh; acting superiorly, flexes vertebral column laterally to balance the trunk; when sitting, acts inferiorly with iliacus to flex trunk
Iliacus Origin
Superior two thirds of iliac fossa, ala of sacrum, and anterior sacro-illiac ligaments
Iliacus Insertion
Lesser trochanter of femur and shaft inferior to it and to psoas major tendon
Iliacus Innveration
Femoral Nerve (L2-L4)
Iliacus Action
Flexes thigh and stabilizes hip joint; acts with psoas major
Quadratus Lumborum Origin
Medial half of inferior border of 12th rib and tips of lumbar transverse processes
Quadratus Lumborum Insertion
Illiolumbar ligament and internal lip of illiac crest
Quadratus Lumborum Innervation
Anterior branches of T12 and L1-L4 nerves
Quadratus Lumborum Action
Extends and laterally flexes vertebral column; fixes 12th rib during inspiration
Psoas Minor Origin
T12-L1 vertbrae and IV discs
Psoas Minor Insertion
Pectineal line and illiopoectineal eminence
Psoas Minor Innervation
Lumbar plexus via anterior branches of nerves L2-L4
Psoas Minor Action
Acting inferiorly with iliacus, flexes thigh; acting superiorly, flexes vertebral column laterally to balance the trunk; when sitting, acts inferiorly with iliacus to flex trunk
Obturator Internus Origin
Pelvic surface of illium and ischium; obturator membrane
Obturator Internus Insertion
Greater trochanter of femur
Obturator Internus Innervation
Nerve to obturator internus (L5, S1, S2)
Obturator Internus Action
Laterally rotates hip joint; assists in holding head of femur in acetabulum
Piriformis Origin
Pelvic surface of 2nd-4th sacral segments; superior margin of greater sciatic notch and sacrotuberous ligament
Piriformis Insertion
Greater trochanter of femur
Piriformis Action
Laterally rotates hip joint; abducts hip joint; assists in holding head of femur in acetabulum
Piriformis Innervation
Anterior rami of S1 and S2
Piriformis Action
Laterally rotates hip joint; abducts hip joint; assists in holding head of femur in acetabulum
Levator Ani (pubococcygeous and illiococcygeus) Origin
Body of pubis, tendinous arch of levator ani, ischial spine
Levator Ani (pubococcygeous and illiococcygeus) Insertion
Perineal body, cocyx, anococcygeal ligament, walls of prostate or vagina, rectum, anal canal
Levator Ani (pubococcygeous and illiococcygeus) Innervation
Nerve to levator ani (branches of S4), inferior anal (rectal) nerve, cocygeal plexus
Levator Ani (pubococcygeous and illiococcygeus) Action
Helps support pelvic visceral; resists increases in intra-abdominal pressure
Coccygeus (ischiococcygeus) Origin
Ischial spine
Coccygeus (ischiococcygeus) Insertion
Inferior end of sacrum and coccyx
Coccygeus (ischiococcygeus) Innervation
Branches of S4 and S5 nerves
Coccygeus (ischiococcygeus) ACtion
Forms small part of pelvic diaphragm that supports pelvic viscera; flexes coccyx
Gluteus Maximus Origin
Illium posterior to posterior gluteal line dorsal surface of sacrum and coccyx; scarotberous ligament
Gluteus Maximus Insertion
Most fibers end in illiotibial tract, which inserts into lateral condyle of tibia; some fibers insert on gluteal tuberosity of femur
Gluteus Maximus Innervation
Inferior gluteal nerve (L5, S1, S2)
Gluteus Maximus Action
Extends hip joint between flexed and standing positions and assists in its lateral rotation; steadies thigh and assists in rising from sitting position
Gluteus Medius Origin
External surface of ilium between anterior and posterior gluteal lines
Gluteus Medius Insertion
Lateral surface of greater trochanter of femur
Gluteus Medius Innervation
Superior gluteal nerve (L4, L5, S1)
Gluteus Medius Action
Abduct and anterior portions medially rotate hip joint; keep pelvis level when opposite limb is elevated
Gluteus Minimus Origin
External surface of illium between anterior and inferior gluteal lines
Gluteus Minimus Insertion
Anterior surface of greater trochanter of femur
Gluteus Minimus Innervation
Superior gluteal nerve (L4, L5, S1)
Gluteus Minimus Action
Abduct and anterior portions medially rotate hip joint; keep pelvis level when opposite limb is elevated
Tensor Fasciae Latae Origin
Anterior superior iliac spine; anterior part of iliac crest
Tensor Fasciae Latae Insertion
Illiotibial tract, which attaches to lateral condyle of tibia (Gerdy’s tubercle)
Tensor Fasciae Latae Innervation
Superior gluteal nerve (L4, L5, S1)
Tesnor Fasciae Latae Action
Flexes hip joint; acts with gluteus maximus to stabilize extended knee joint
Gemelli superior and inferior Origin
Superior: Ischial spine
Inferior: Ischial tuberosity
Gemelli superior and inferior Insertion
Medial surface of greater trochanter of femur
Gemelli superior and inferior Innervation
Superior: nerve to obturator internus (L5, S1)
Inferior: nerve to quadratus femoris (L5, S1)
Gemelli superior and inferior Action
Laterally rotate exteneded hip joint; abduct flexed hip joint; steady femoral head in acetabulum (stabilizes hip joint)
Quadratus Femoris Origin
Lateral border of ischial tuberosity
Quadratus Femoris Insertion
Quadrate tubercle on intertrochanteric crest of femur and area inferior to it
Quadratus Femoris Innervation
Nerve to quadratus femoris (L5, S1)
Quadratus Femoris Action
Laterally rotates hip joint; also pulls femoral head into acetabulum to stabilize hip joint/pelvis
Semitendinosus Origin
Ischial tuberosity
Semitendinosus Insertion
Medial surface of superior part of tibia
Semitendinosus Innervation
Tibial division of sciatic nerve (L5, S1, S2)
Semitendinosus Action
Extend hip joint; flex knee joint and rotate the leg medially when knee is flexed; when hip and knee are flexed, can extend trunk
Semimembranosus Origin
Ischial Tuberosity
Semimembranosus Insertion
Posterior part of medial condyle of tibia; reflected attachment forms oblique popliteal ligament
Semimembranosus Innervation
Tibial division of sciatic nerve (L5, S1, S2)
Semimembranosus Action
Extend hip joint; flex knee joint and rotate the leg medially when knee is flexed; when hip and knee are flexed, can extend trunk
Biceps femoris Origin
Long head: Ischial tuberosity
Short head: Linea aspera and lateral supracondylar line of femur
Biceps femoris Insertion
Lateral side of head of fibula; tendon is split at this site by fibular collateral ligament of knee
Biceps femoris Innervation
Long head: tibial division of sciatic nerve (L5, S1, S2)
Short head: common fibular division of sciatic nerve (L5, S1, S2)
Biceps femoris Action
Flexes knee joint and rotates it laterally when knee is flexed; extends hip joint
Pectineus Origin
Superior ramus of pubis
Pectineus Insertion
Pectineal line of femur, just inferior to lesser trochanter
Pectineus Innervation
Femoral Nerve (L2, L3); may receive branch from obturator nerve
Pectineus Action
Adducts and flexes hip joint; assists with medial rotation of hip joint
Sartorius Origin
Anterior superior illiac spiceand superior part of notch inferior to it
Sartorius Insertion
Superior part of medial surface of tibia
Sartorius Innervation
Femoral Nerve (L2, L3)
Sartorius Action
Flexes, abducts, and laterally rotates hip joint; flexes knee joint
Rectus Femoris Origin
Anterior inferior illiac spine and ilium superior to acetabulum
Rectus Femoris Insertion
Quadriceps tendon
Rectus Femoris Innervation
Femoral Nerve (L2, L3, L4)
Rectus Femoris Action
Extends knee joint; stabilizes hip joint and helps iliopsoas flex hip joint
Vastus Lateralis Origin
Greater trochanter and lateral lip of linea aspera
Vastus Lateralis Insertion
Quadriceps tendon, tibia and patella via aponeuroses
Vastus Lateralis Innervation
Femoral Nerve (L2, L3, L4)
Vastus Lateralis Action
Extends knee joint
Vastus Medialis Origin
Intertrochanteric line and medial lip of linea aspera
Vastus Medialis Insertion
Quadriceps tendon, tibia and patella via aponeuroses
Vastus Medialis Innervation
Femoral Nerve (L2, L3, L4)
Vastus Intermedius Origin
Anterior and lateral surfaces of shaft of femur
Vastus Intermedius Insertion
Quadriceps tendon
Vastus Intermedius Innervation
Femoral Nerve (L2, L3, L4)
Vastus Intermedius Action
Extends knee joint
Adductor Longus Origin
Body of pubis inferior to pubic crest
Adductor Longus Insertion
Middle third of linea aspera of femur
Adductor Longus Innervation
Obturator Nerve (L2, L3, L4)
Adductor Longus Action
Adducts hip joint
Adductor Brevis Origin
Body and inferior ramus of pubis
Adductor Brevis Insertion
Pectineal line and proximal part of linea aspera of femur
Adductor Brevis Innervation
Obturator Nerve (L2, L3, L4)
Adductor Brevis Action
Adductss hip joint and to some extend flexes it
Adductor Magnus Origin
Adductor part: inferior ramus of pubis, ramus of ischium
Hamstring part: ischial tuberosity
Adductor Magnus Insertion
Adductor part: gluteal tuberosity, linea apsera, medial supracondylar line
Hamstring part: adductor tubercle of femur
Adductor Magnus Innervation
Adductor part: obturator nerve (L2, L3, L4)
Hamstring part: tibial part of sciatic nerve (L4)
Adductor Magnus Action
Adducts hip joint; its adductor part also flexes hip joint, and its hamstring part extends it
Gracilis Origin
Body and inferior ramus of pubis
Gracilis Insertion
Superior part of medial surface of tibia
Gracilis Innervation
Obturator nerve (L2, L3)
Gracilis Action
Adducts hip joint; flexes knee joint and helps rotate it medially
Obturator Externus Origin
Margins of obturator foramen and obturator membrane
Obturator Externus Insertion
Trochanteric fossa of femur
Obturator Externus Innervation
Obturator Nerve (L3, L4)
Obturator Externus Action
Laterally rotates hip joint; pulls head of femur into acetabulum holding pelvis steady