Muscle Anatomy: Origins, Insertions, Actions, and Innervations

Comprehensive flashcards covering muscle origins, insertions, actions, and innervations as described in the lecture notes.

What are the back muscles that make up the Superficial Extrinsic layer?

• Trapezius

• Rhomboid Major/Minor

• Levator Scapulae

• Latissimus Dorsi

What is the OIAN of the Trapezius?

O= EOP, medial portion of superior nuchal line, nuchal ligament, and SP C7-T12

I= lateral 1/3 of clavicle, acromion, and spine of scapula

A= descending fibers= ELEV

middle fibers= RETR

ascending fibers= DEPR

INE= cranial n. #11 (accessory nerve)

What is the OIAN of the Lats?

O= posterior sacrum, medial portion of posterior iliac crest, thoracolumbar fascia, and SP T6-12

I= medial crest of the intertubercular sulcus

A= EXT, ADD, and IR of shoulder

INE= thoracodorsal n. (C6-8)

What is the OIAN of the Levator Scapulae?

O= posterior tubercles on TP of C1-4

I= superior medial border of scapula, right above root of spine of scapula

A= ELEV, DR

INE= dorsal scapular n. (C5)

What is the OIAN of Rhomboid Minor?

O= nuchal ligament and SP C7-T1

I= medial end of spine of scapula

A= RETR, downward rotation, and fix scapula to thoracic wall

INE= dorsal scapular n. (C5)

What is the OIAN of the Rhomboid Major?

O= SP T2-5

I= the poriton b/t the medial end of scapular spine to inferior angle of scapula

A= RETR, DR, and fix scapula to thoracic wall

INE= dorsal scapular n, (C5)

What are the back muscles that make up the intermeditate extrinsic layer?

• serratus posterior superior

• serratus posterior inferior

What is the OIAN of the serratus posterior superior?

O= nuchal ligament and SP C7-T3

I= superior border of rubs 2-4

A= ELEV ribs for inhalation

INE= intercostal n. of ribs 2-5

What is the OIAN of the serratus posterior inferior?

O= SP T11-L2

I= inferior border of ribs 8-12

A= DEPR ribs for exhalation

INE= spinal nerves T9-12

What are the back muscles that make up the superficial intrinsic layer?

• splenius capitis

• splenius cervicis

What is the OIAN of the splenius capitis?

O= nuchal ligament and SP C7-T6

I= mastoid process and lateral 1/3 of superior nuchal line

A= neck and head EXT, IPL SB, and IPL ROT

INE= dorsal ramii

What is the OIAN of the splenius cervicis?

O= nuchal ligament and SP of C7-T6

I= TP of C1-3

A= head and neck EXT, IPL SB, and IPL ROT

INE= dorsal ramii

What are the back muscles that make up the intermediate intrinsic layer?

• the erector spinae group

What are the specific parts and their sub-parts of the erector spinae group?

• iliocostalis

  • lumborum

  • thoracis

  • cervicis

• longissimus

  • thoracis

  • cervicis

  • capitis

• spinalis

  • thoracis

  • cervicis

  • capitis

What is the OIAN of the iliocostalis lumborum?

O= posterior iliac crest, sacrum, SP of lumbar and sacral spine, supraspinous ligament

I= angles of lower ribs

A= trunk EXT and IPL SB

INE= dorsal ramii

What is the OIAN of the iliocostalis thoracis?

O= angles of lower ribs

I= angles of upper ribs

A= trunk EXT, IPL SB

INE= dorsal ramii

What is the OIAN of the iliocostalis cervicis?

O= angles of upper ribs

I= TP of cervical spine

A= trunk EXT and IPL SB

INE= dorsal ramii

What is the OIAN of the longissimus thoracis?

O= posterior iliac crest, sacrum, SP of lumbar and sacral spine, supraspinois ligament

I= b/t the angles and tubercles of the ribs

A= trunk EXT and IPL SB

INE= dorsal ramii

What is the OIAN of the longissimus cervicis?

O= TP of upper thoracic

I= TP of thoracic and cervical spine

A= trunk EXT and IPL SB

INE= dorsal ramii

What is the OIAN of the longissimus capitis?

O= articular processes of upper cervical

I= mastoid process

A= trunk EXT and IPL SB

INE= dorsal ramii

What is the OIAN of the spinalis thoracis?

O= SP of T10-12

I= SP of thoracic vertebrae and the skull

A= trunk EXT and IPL SB

INE= dorsal ramii

What are the back muscles. that make up the deep intrinsic layer?

• transversospinalis muscles

  • semispinalis

  • multifidus

  • rotatores

• interspinalis

• intertransversarri

• levator costrum

What is the OIAN of the semi-spinalis muscle?

(spans 4-6 segments)

O= TP within the region of C4-T12

I= SP within the region of C4-T12

A= EXT and CL ROT of head

INE= dorsal ramii

What is the OIAN of the multifidus?

(spans 2-4 segments)

O= TP (mostly in lumbar region)

I= SP (mostly in lumbar region)

A= head EXT, IPL SB and CL ROT (stabilization)

INE= dorsal ramii

What is the OIAN of the rotatores?

O= TP

I= SP (spanning 1-2 segments)

• longus= spans 2 segments

• brevis= spans 1 segment

A= sensory information, also some EXT and CL ROT

INE= dorsal ramii

What is the action and innervation of the interspinalis?

A= prevent ligaments from being torn by performing some extension and ROT (fine tune movements)

INE= dorsal ramii

What is the action and innervation of the intertransversarri?

A= IPL SB and stabilization

INE= dorsal ramii

What is the OIAN of the Levator Costrum?

O= TP

I= ribs

• longus= crosses a segment and then attaches

• brevis= attaches between segments

A= aid with respiration (especially ELEV of ribs for inhalation)

INE= dorsal rami

What is the OIAN for the Deltoids?

Anterior (clvaicular) part- unipenate

• O= lateral 1/3 of clavicle

• I= deltoid tuberosity

• A= FLX and IR

• INE= axillary nerve (C5-6)

Middle (acomial) part- multipenate

• O= acromion of scapula

• I= deltoid tuberosity

• A= ABD

• INE= axillary nerve (C5-6)

Posterior (spinal) part- unipenate

• O= spine of scapula

• I= deltoid tuberosity

• A= EXT and ER

• INE= axillary nerve (C5-6)

What are the OIAN of the supraspinatis muscle?

O= supraspinous fossa of scapula

I= superior facet of the greater tubercle

A= first 15 degrees of shoulder ABD

INE= suprascapular nerve (C5-6)

What is the OIAN of the infraspinatis?

O= infraspinous fossa

I= middle facet of the greater tubercle

A= ER

INE= suprascapular nerve (C5-6)

What is the OIAN of teres minor?

O= middle lateral border of the scapula

I= inferior facet of the greater tubercle

A= minor ER

INE= axillary nerve (C5-6)

WHat is the OIAN of the subscapularis muscle?

O= subscapular fossa

I= lesser tubercle

A= IR and ADD

INE= upper and lower subscapular nerves (both C5-6)

WHat is the OIAN of teres major?

o= posterior inferior angle of the scapula

I= medial crest of the intertubecular sulcus

A= ADD, IR, and slight EXT

INE= lower subscapular nerve (C5-6)

What is the OIAN for the Triceps, long head?

O= infraglenoid tubercle of scapula

I= proximal olecronon and forearm fasica

A= elbow EXT, shoulder EXT and steadies teh head of the humerus when the arm is ABD

INE= radial nerve (C6-8)

What is the OIAN of the serratus anterior?

O= external/lateral surface of ribs 1-8

I= anterior surface of the vetebral border of scapula

A= PRO, UR, and holds scapula tight against the thoracic wall

INE= long thoracic nerve (C5-7)

What is the OIAN of the pectoralis major?

O= anteior sternum, anteriomedial clavicle, superior 6 costal cartilages, and aponerosis of the external obliques

I= anterior lateral crest of the intertubercular groove

A= powerful ADD, but also PROT, DR, and IR

INE= lateral pectoral nerve (clavicular head) (C5-7)

part of the lateral pectoral nerve (just C7) and medial pectoral nerve (C8-T1) for the sternalcostal head

What is the OIAN for pec minor?

O= anterior surface of ribs 3-5

I= medial superior surface of the coracoid process of scapula

A= scapular setting= stabalizes scapula when reaching for something

INE= only medial pectoral nerve (C8-T1)

What is the OIAN of the subclavius muscle?

O= junction between the first rib and its costal cartilage

I= inferior middle 1/3 surface of the clavicle at the subclavian groove

A= DEPR and stabalize clavicle

INE= nerve to subclavius (C5-6)

What is the OIAN of the biceps brachii?

O= Long head= supraglenoid tubericle of scapula

short head= inferior lateral coracoid process of scapula

I= both heads onto the radial tuberosity and bicipital aponerosis ehich blends into the forearm fascia

A= both heads= elbow FLX, shoulder FLX, and forearm SUP

INE= both heads= musculocutaneous (C5-6)

What is the OIAN of the coracobrachialis?

O= inferior medial aspect of the coracoid process

I= middle 1/3 of medial humerus

A= shoulder FLX and assists with ADD

INE= musculocutaneous (C5-C7)

What is the OIAN of the brachialis?

O= distal ½ of anteior humerus

I= coronoid process and ulnar tuberosity

A= main elbow flexor

INE= medial= musculocutaneous (C5-6) and lateral= radial (C5 and C7)

What is the OIAN of the triceps lateral head?

O= posterior humerus, superior to radial groove

I= proximal olecronon and forearm fascia

A= elbow EXT

INE- radial nerve (C6-8)

What is the OIAN of the triceps medial head?

O= posterior humerus, inferior to radial groove

I= proximal olecronon and forearm fascia

A= elbow EXT

INE= radial nerve (C6-8)

What is the OIAN of the anconeus?

O= lateral epicondyle of humerus

I= lateral olecronon to superior and posterior ulna

A= assists triceps with elbow EXT, also ABD arm when in forearm PRO

INE= radial nerve (C7-T1)

What is the OIAN of the Pronater Teres?

O= ME and coronoid process of ulna

I= middle, lateral radius

A= PRO and elbow FLX

INE= median nerve (C6-C7)

What is the OIAN of the Flexor Carpi Radialis?

O= ME

I= base of 2nd MC

A= wrist FLX and RD

INE= median nerve (C6-7)

What is the OIAN of the Palmaris Longus?

O= ME

I= distal half of the anterior retineculum and palmar aponerosis

A= wrist FLX and tighten the palmar aponerosis

INE= median (C7-8)

What is the OIAN of the Flexor Carpi Ulnaris?

O= ME and olecronon/posterior ulna

I= pisiform, hook of hemmate, and 5th MC

A= wrist FLX and UD

INE= ulnar nerve (C7-8)

What is the OIAN of the Flexor Digitorum Superficialis?

O= humeroulnar= ME, ulnar collateral ligament, and coronoid process

radial head= anterior, superior hald of radius

I= bodies of the medial 4 middle phalanges

A= FLX of PIP, MCP, and wrist

INE= median nerve (C7-T1)

What is the OIAN of the Flexor Digitorum Profundis?

O= anterior proximal ¾ of the medial ulna and interosseus membrane

I= base of the medial 4 distal phalanges

A= FLX of DIP, MCP, wrist

INE= medial portion= ulnar (C8-T1) and lateral portion= anterior interosseus nerve (C8-T1)

What is the OIAN of Flexor Pollicis Longus?

O= anterior radius and interosseus membrane

I= base of distal phalanx of thumb

A= FLX of IP of thumb

INE= anterior interosseus nerve (C8-T1)

What is the OIAN of Pronator Quadratus?

O= distal ¼ of anterior ulna

I= distal ¼ of anterior radius

A= PRO and bind radius and ulna together

INE= anterior interosseus nerve (C8-T1)

What is the OIAN of the brachioradialis?

O= proximal 2/3 of lateral supracondylar ridge

I= lateral, distal radius

A= elbow FLX

INE= radial nerve (C5-7)

What is the OIAN of the Extensor Carpi Radialis Longus?

O= distal lateral supracondylar ridge

I= base of 2nd MC

A= wrist EXT, RD, and weak elbow FLX

INE= radial nerve (C6-7)

What is the OIAN of the Extensor Carpi Radialis Brevis?

O= LE

I= base of the 3rd MC

A= wrist EXT, RD, and weak elbow FLX

INE= deep radial nerve (C7-8)

What is the OIAN of the Extensor Digitorum?

O= LE

I= extensor expansion of medial 4 digits

A= EXT of medial 4 digits at their MCP joints and wrist EXT

INE= deep radial nerve (C7-8)

What is the OIAN of Extensor Digiti Minimi?

O= LE

I= extensor expansion of 5th digit

A= EXT 5th digit at the MCP

INE= deep radial (C7-8)

What is the OIAN of the extensor carpi ulnaris?

O= LE and posterior ulna

I= base ofo 5th MC

A= wrist EXT and UD

INE= deep radial (C7-8)

Wha tis the OIAN of the Supinator?

O= LE, supinator fossa, crest of ulna, radial collateral ligament, and anular ligament

I= proximal 1/3 of radius (anterior, lateral, proximal aspect)

A= SUP

INE= deep radial (C7-8)

What is the OIAN of the Extensor Indicis?

O= posterior ulna and interosseus membrane

I= extensor expansion of the 2nd digit

A= EXT of 2nd digit at the MCP and wrist EXT

INE= posterior interosseus (C7-8)

What is the OIAN of Abductor Pollicis Longus?

O= posterior ulna, radius, and interosseus membrane

I= base of 1st MC

A= ABD thumb, EXT thumb at CMC, and wrist RD

INE= posterior interosseus (C7-8)

What is the OIAN of the Extensor Pollicis Longus?

O= posterior middle 1/3 of ulna and interosseus membrane

I= distal phalanx of thumb

A= EXT thumb at the IP and MCP joints

INE= posterior interosseus (C7-8)

What is the OIAN of the Extensor Pollicis Brevis?

O= posterior radius and interosseus membrane

I= proximal phalanx of thumb

A= EXT of thumb at MCP

INE= posterior interosseus (C7-8)

What are the four muscles that make up the themar eminence?

• abductor policis brevis

• flexor policis brevis

• adductor policis

• opponens policis

OF the four themar hand muscles which ones are innervated by the recurrent branch of the median n.?

• abductor policis brevis

• superficial head of flexor policis brevis

• opponens policis

Of the four themar hand muscles, which are innervated by the deeo branch of the ulnar n.?

• adductor policis

• deep head of flexor policis brevis

What is the OIAN of the abductor policis brevis?

O= flexor retinaculum, tubercles of scaphoid and trapezium

I= lateral side of base of proximal phalanz of thumb

A= ABD and assist with opposition

INE= recurrent branch of median n. (C8-T1)

What is the OIAN of the Flexor Policis Brevis?

O= flexor retinaculum, tubercles of scaphoid and trapezium

I= lateral side of base of proximal phalanx of thumb

A= superficial head= FLX of thumb

deep head= ADD of thumb

INE= superficial head= recurrent branch of median n (C8-T1)

deep head= deep branch of ulnar n. (C8-T1)

What is the OIAN of Adductor Policis?

O= oblique head= base of 2nd and 3rd MC, capitate, adjacent carpals

transverse head= anterior shaft of 3rd MC

I= both heads= medial base of proximal phalanx of thumb

A= ADD of thumb

INE= deep branch of ulnar n. (C8-T1)

What is the OIAN of opponens policis?

O= flexor retinaculum, capitate, and adjacent carpals

I= lateral side of 1st MC

A= opposition

INE= recurrent branch of median n. (C8-T1)

What are the three muscles that make up the hypothemar eminence?

• abducor DM

• flexor DM

• opponens DM

What is the common innervation of all three hypothemar muscles?

deep branch of ulnar n. (C8-T1)

What is the OIAN of the abductor digiti minimi?

O= pisiform

I= base of proximal phalanx of 5th digit on medial side

A= ABD pinkt and assist with FLX at PIP

INE= deep ulnar n. (C8-T1)

What is the OIAN of the flexor digiti minimi?

O= hook of hamate and flexor retinaculum

I= base of proximal phalanx of 5th digit on medial side

A= FLX pinky at PIP

INE= deep branch of ulnar n. (C8-T1)

What is the OIAN of the opponens digiti minimi?

O= hook of hamate and flexor retinaculum

I= medial border of 5th MC

A= opposition

INE= deep branch of ulnar n. (C8-T1)

What is the OIAN of the lumbercals?

O= FDP tendons

I= extensor expansion

A= EXT of PIP and DID, FLX MCP of digits 2-5

INE=

• L1= lateral median n.

• L2= medial median n.

• L3+4= deep ulnar n.

(all C8-T1)

What is the OIAN of the palmar interossei?

O= palmar surface of MC 2.4.5

I= extensor expansions and base of proximal phalanx of digits 2,4,5

A= ADD and assist lumbercals

INE= deep ulnar n. (C8-T1)

What is the OIAN of the dorsal interossei?

O= adjacent 2 MC

I= extensor expansions and base of proximal phalanx of digits 2,3,4

A= ABD and sssist lumbercals

INE= depp ulnar n. (C8-T1)

What is the action and innervation of the palmaris brevis?

A= tightens base of hypothemar for stronger grip

• not actually part of the hypothemar muscles, it is within the subcutaneous tissue

INE= superficial branch of ulnar n. (C8-T1)

What is the OIA of the transversus thoracis muscles?

O= posterior sternum

I= midclavicular line

A= weak expirartory function by DEPR the ribs

What is the OIAN of the subcostal muscles?

O= internal surface of the lower ribs near the sternal angle

I= cross 1-2 spaces and inset on the ribs above

A= DEPR ribs

INE= intercostal nerves

What is the OIAN of the rectus abdominis?

O= pubic symphysis and pubic crest

I= xyphoid process and costal cartilages of ribs 5-7

A= trunk FLX, compress and stabilize viscera, control lumbar lordosis

INE= thoracoabdominal (ventral rami T6-12)

What is teh OIAN of the external obliques?

O= superiolateral external surface of ribs 5-12

I= anterior 1/3 of iliac crest, inferiomedial linea albs , pubic tubercle

A=

INE= thoracoabdominal (T7-T11) and subcostal n.

What is the OIAN of the internal obliques?

O= thoracolumbar fascia, anterior 2/3 of iliac crest, connectinve tissues deep to the lateral 1/3 of the inguinal ligament

I= inferior borders of ribs 10-12, linea alba, pectin pubis

A=

INE= thoracoabdominal n. (T6-T12) and 1st lumbar n.

What is the OIAN of the transversus abdominis?

O= thoracolumbar fascia, internal surfaces of costal cartilages of ribs 7-12, iliac crest, connective tissue deep to lateral 1/3 of inguinal ligament

I= linea alba, pectin pubis, and pubic crest

A= compression and stabilization of viscera

INE= thoracoabdominal n. (ventral rami T6-12) and 1st lumbar n.

What is the OIAN of the diaphragm?

O= internal surfaces of the ribs and vertebrae

I= into itself by way of central tendon

A= contracts and expand during inhalation

INE= phrenic n. (C3-5)

What is the OIAN of the quadratus lumborum?

O= inferior medial 1/2 border of 12th rib, TP of lumbar spine

I= internal lip of iliac crest and iliolumbar ligament

A= EXT and IPL FLX of vertebral column, holds rib cage down during inhalation

INE= ventral rami T12-L4

What is the OIAN of the psoas major?

O= TP of lumbar spine and sides of vertebral bodies (and their discs) of T12-L5

I= lesser trochanter of femur and the sahft just inferior to it

A= hip FLX

INE= ventral rami L1-3

What is the OIAN of the psoas minor?

O= sides of vertebral bodies (and their discs) of T12-L1

I= pectineal line and iliopectineal eminence

A= assists psoas major with hip FLX

INE= ventral rami L1-2