Myology Flashcards
What are the attachment points of trapezius m.?
thoracic spinous processes, external occipital protuberance, clavicle, acromion, and scapular spine
What is the action and Innervation of the trapezius m.?
Rotate glenoid cavity superiority, retract the scapula, elevate scapula, depress scapula, extend the neck (with bilateral contraction), laterally flex the neck and rotate the face away (with unilateral contraction)
Spinal Accessory N.
What are the attachment points for Latissimus Dorsi M.?
Thoracic spinous process, ribs, Inferior scapula, Intertubercular groove of the humerus, and iliac crest
What is the action and Innervation of Latissimus Dorsi M.?
Extend, ADduct, and medically rotate the humerus, rotate the glenoid cavity inferiority
N: Thoracodorsal
What are the attachment points for rhomboid major and minor?
Major: thoracic spinous processes and medial border of scapula, inferior to the scapular spine
Minor: thoracic spinous processes and medial border of scapula, at the level of the scapular spine
What is the innervation for Rhomboid major, minor, and levator scapulae m.?
Dorsal Scapular N.
What are the attachment points for Levator Scapulae M.?
Cervical transverse processes and medial border of scapula, superior to the scapular spine
What are the actions of rhomboid major, minor, and levator scapulae?
Major and Minor: Retract and elevate the scapula, rotate the glenoid cavity inferiorly
Levator: Elevate scapula, rotate the glenoid cavity inferiorly, extend and laterally flex the neck (when bilaterally and unilaterally contracting, respectively)
What muscles are in Layer 3 and what are their functions?
Serratus Posterior Superior: elevate ribs with forced inspiration (but primarily proprioception)
Serratus Posterior Inferior: depress ribs with forced expiration (but primarily proprioception)
What are the attachments for and innervations for Serratus Posterior Inferior/Superior?
S. P. Superior: nuchal line and cervical/thoracic spinal processes, and superior surfaces of ribs
N: Intercostal nerves (2-5)
S.P. Inferior: Thoracic/lumbar spinal processes and inferior surface of ribs
N: Anterior Rami T9-12
What layer are Splenius Capitus M. and Splenius Cervicis M. In and where do they respectively attach?
They are both in layer 4.
Splenius Capitus: mastoid process of temporal bone, cervical/thoracic spinous processes, and ligamentum nuchae
Splenius Cervicis: thoracic spinous processes and cervical transverse processes
What are the actions and innervations of Splenius Cervicis and Splenius Capitus?
Splenius Cervicis: Extend the neck (when contracting bilaterally), laterally flex the neck and rotate the face toward the muscle (when contracting unilaterally)
N: Posterior Rami C5-C7
Splenius Capitus: Extend the neck (when contracting bilaterally), laterally flex the neck and rotate the face toward the muscle (when contracting unilaterally) [SAME AS CERVICIS]
N: Posterior Rami C3-C7
What is the action and innervation of the Erector Spinae Group and what are they from lateral to medial?
They maintain erect posture and extend the vertebral column and head (when contracting bilaterally), and laterally flex the vertebral column (when contracting unilaterally)
N: Posterior rami of spinal nerves
Iliocostalis, Longissimus, and Spinalis
What are the different regions of Iliocostalis and their respective attachment points?
Iliocostalis Lumborum M.: Attaches from the iliac crest, to thoracic/lumbar spinal processes, sacral crest, and costal angles of ribs
Iliocostalis Thoracis M.: Costal angles of ribs and transverse process C7
Iliocostalis Cervicis M.: Costal angles of ribs and posterior tubercles of cervical transverse processes
What are the different regions of Longissimus and their respective attachment points?
Longissimus Thoracis M.: Iliac crest, sacral crest, and thoracic/lumbar spinous processes, thoracic transverse processes, and ribs
Longissimus Cervicis M.: Thoracic transverse processes and cervical posterior tubercles of transverse processes
Longissimus Capitis M.: Thoracic transverse processes, cervical articulated processes, and mastoid process of the temporal bone
What are the regional Spinalis muscles and what are their respective attachment points?
Spinalis Thoracis M.: Thoracic/lumbar spinous processes to upper thoracic spinous processes
Spinalis Cervicis M.: Thoracic spinous processes to cervical spinous processes
Spinalis Capitis M.: Usually absent or blended with Semispinalis Capitis M.
Over how many spinal segments does the semispinalis group extend and what are they innervated by?
5-6 segments
N: Posterior Rami
What are the regional separations for the semispinalis muscles and their respective actions/attachments?
Semispinalis Thoracis: Extends spine and rotates the spine away; attaches to thoracic transverse processes and upper thoracic/lower cervical spinous processes
Semispinalis Cervicis: Extends the spine and rotates the spine away; attaches to the upper thoracic transverse processes and cervical spinous processes
Semispinalis Capitis: Extends the head and rotates the face away; attaches to the cervical transverse processes and between the superior and inferior nuchal lines of the occipital bone
What are the actions of Multifidus, Rotatores Longus, and Rotatores Brevis, and what are they innervated by?
They all extend the spine and rotate the spine away
N: Posterior Rami
How many spinal segments do Multifidus, Rotatores Longus, and Rotatores Brevis extend over?
Multifidus: 3-4 segments
Rotatores Longus: 2 segments
Rotatores Brevis: 1 segment
What are the other deep back muscles and their innervation?
Interspinalis, Intertransversarii, levator cosatrum Longus, and levator cosatrum brevis
N: Posterior Rami
What are the attachments and their actions for the “other deep back muscles”?
Interspinalis: spinous process to adjacent spinous process; extend spine
Intertransversarii: transverse process to adjacent transverse process; laterally flex spine
Levator Costarum Longus: Transverse processes to 2nd rib inferior to the origin; elevate ribs
Levator Costarum Brevis: Transverse processes to adjacent rib inferior to origin; elevate ribs
What is the innervation for the Suboccipital muscles and what are they?
N: Suboccipital N.
Rectus Capitis Posterior Minor & Major
Obliquus Capitis Inferior and Superior
What makes up the Suboccipital triangle?
Rectus Capitis posterior major (medial border), Obliquus Capitis inferior (inferior border), and Obliquus Capitis Superior (lateral border)
What are the attachments and actions for Rectus Capitis Posterior Major and Minor?
Major: C2 spinous process and the lateral portion of the inferior nuchal line; extend head and rotate face toward the muscle
Minor: Posterior tubercle of C1 and just below the inferior nuchal line; extend the head
What are the attachments and actions for Obliquus Capitis Superior and Inferior?
Superior: Transverse process of C1 to in between superior and inferior nuchal lines; extend and laterally flex the head
Inferior: C2 spinous process to transverse process of C1; rotate the face toward the muscle
What are the attachments and action of Pectoralis Major M.?
It attaches to the clavicle, sternum, costal cartilage, the aponeurosis of the abdominal muscles, and the anteriolateral edge of the humerus
It ADducts and medically rotates the humerus, protracted and depresses the scapula, flexes the humerus, and extends the humerus when it is in the flexed state
What are the attachments and action of Pectoralis Minor M.?
The medial portion of the ribs and the coracoacromial process of the scapula
It stabilizes the scapula by protraction great and depressing it agains the thoracic wall
What are the innervations for the Pectoralis Major and Minor M.?
Major: Medial and Lateral Pectoral N.
Minor: Medial Pectoral N.
Where does the Subclavius M sit and what does it do?
It sits below the clavicle, in between the clavicle and 1st rib
It positions and depresses the clavicle
What innervates the Subclavius M.?
Subclavian Nerve
Where does Serratus Anterior M. attach and what does it do?
It attaches to the lateral external surface of the ribs and the anterior surface of the medial border of the scapula
It protracts the scapula, stabilizing it against the thoracic wall, and it rotates the glenoid cavity superiority
What innervates and supplies Serratus Anterior M.?
Long Thoracic Nerve and the Lateral Thoracic Artery
Where does the Deltoid M. attach and what does it do?
It attaches to the clavicle, scapular spine, acromion, and deltoid tuberosity on the humerus
Anterior part: Flexes and medially rotates the humerus
Middle part: ABducts the humerus
Posterior part: Extend and laterally rotates the humerus
What innervates and supplies the deltoid M.?
Axillary Nerve and Posterior Circumflex Humeral Artery
What are the rotator cuff muscles?
Subscapularis, Supraspinatus, Infraspinatus, and Teres Minor
Where does subscapularis attach and what does it do?
It attaches to the subscapular fossa and the humerus
It medially rotates and ADducts the humerus, and helps hold the humeral head in the glenoid cavity
Where does Supraspinatus attach and what does it do?
It attaches to the supraspinous fossa of the scapula and the greater tubercle of the humerus
It ABducts the humerus and helps to hold the humeral head in the glenoid cavity
Where does Infraspinatus sit and what does it do?
It attaches to the infraspinous fossa of the scapula and the greater tubercle of the humerus
It laterally rotates the humerus and helps to hold the humeral head in the glenoid cavity
What innervates Subscapularis, Supraspinatus, and Infraspinatus?
Subscapularis: Upper and Lower Subscapular Nerve
Supraspinatus: Suprascapular N.
Infraspinatus: Suprascapular N.
Where does Teres Minor attach and what does it do?
It attaches to the middle portion of the lateral border of the scapula
It laterally rotates the humerus and helps to hold the humeral head in the glenoid cavity
Where does Teres Major attach and what does it do?
It attaches to the posterior aspect of the inferior angle of the scapula and the intertubercular groove of the humerus
It ADducts and medially rotates the humerus
What are Teres Minor and Major innervated by?
Minor: Axillary N (same as the deltoid)
Major: Lower Subscapular N.
What are the borders of the triangular space and what runs through it?
Borders: Teres Minor, Teres Major, and Long head of the Triceps Brachii
Circumflex Scapular Artery runs through it
What are the borders of the quadrangular space and what runs through it?
Borders: Teres Minor, Teres Major, Long and Lateral heads of the Triceps Brachii
Posterior Circumflex Humeral Artery and Axillary Nerve run through it
What are the borders of the triangular interval and what runs through it?
Borders: Teres Major, Long and Lateral heads of the Triceps Brachii
Deep Brachial Artery and Radial Nerve run through it
What muscles does the Musculocutaneous nerve innervate?
Biceps Brachii, Coracobrachialis, and Brachialis
What are the attachments for the Biceps Brachii and what does it do?
Long head: Supraglenoid tubercle of the scapula to the radial tuberosity/antebrachial fascia as the bicipital aponeurosis
Short head: Coracoid process of the scapula (to the same insertion point)
It flexes the humerus and forearm, and it supinates the forearm
Where does the Coracobrachialis M. attach and what does it do?
The coracoid process of the scapula and the medial aspect of the humerus
It flexes and ADducts the humerus
Where does the brachialis attach and what does it do?
It attaches to the distal anterior aspect of the humerus to the ulnar tuberosity/Coronoid process
It flexes the forearm
What nerve innervates Triceps Brachii and Anconeus?
Radial Nerve
What muscles are part of the anterior compartment of the brachium?
Biceps Brachii, Coracobrachialis, brachialis
What nerve innervates the anterior compartment of the brachium?
Musculocutaneous
What muscles are part of the posterior compartment of the brachium?
Triceps Brachii and Anconeous
Where do the Triceps Brachii attach and what do they do?
Long Head: infraglenoid tubercle of the scapula
Medial Head: posterior aspect of the humeral body
Lateral Head: posterior aspect of the humeral body
- All attach to the olecranon
They extend the forearm
Where does the anconeous attach and what does it do?
Lateral humeral epicondyle and olecranon
It helps extend the forearm and stabilize the elbow joint
What muscles are in the superficial layer of FLEXORS?
Pronator Teres, Flexor Carpi Radialis, Palmaris Longus, Flexor Carpi Ulnaris
What innervates Pronator Teres, Flexor Carpi Radialis, and Palmaris Longus?
Median N.
What innervates Flexor Carpi Ulnaris?
Ulnar N.
Where do all the superficial layer of flexors originate from?
Medial Humeral Epicondyle
Where does Pronator Teres insert into and what does it do?
It inserts into the lateral aspect of the radius
It pronates and flexes the arm
Where does Flexor Carpi Radialis insert and what does it do?
It inserts into the base of the 2nd metacarpal
It flexes the forearm, and flexes and ABducts the hand at the wrist
Where does Palmaris Longus insert and what does it do?
It inserts into the palmar aponeurosis and flexor retinaculum
It flexes the forearm, and flexes the hand and tenses the palmar aponeurosis
Where does the Flexor Carpi Ulnaris insert and what does it do?
It inserts into the pisiform, hamate hook, and base of the 5th metacarpal
It flexes the forearm, and flexes and ADducts the hand at the wrist
What muscles are part of the Intermediate Layer of FLEXORS?
Flexor Digitorum Superficialis
What innervates Flexor Digitorum Superficialis?
Median N.
Where does Flexor Digitorum Superficialis attach and what does it do?
It attaches from the medial humeral epicondyle, anteriosuperior part of the radius, and coronoid process of the ulna to the intermediate phalanges of digits 2-5
It flexes the forearm, flexes the hand at the wrist, flexes the proximal and intermediate phalanges of digits 2-5
What muscles are in the deep layer of FLEXORS?
Flexor Digitorum Profundus, Flexor Pollicis Longus, Pronator Quadratus
What innervates the muscles of the deep layer of flexors?
Anterior Interosseous N. (A branch of the median N.)
Where does Flexor Digitorum Profundus attach and what does it do?
It attaches from the ulna and interosseous membrane to the bases of the distal phalanges 2-5
NOTE: the tendon passes through the bifed tendon on the Flexor Digitorum Superificialis
It flexes the hand at the wrist, flexes all phalanges of digits 2-5 at the Metacarpophalangeal/proximal/distal interphalangeal joints
Where does the Flexor Pollicis Longus attach and what does it do?
It attaches on the radius and interosseous membrane to the base of the distal phalanx of the Pollux
It flexes the hand, flexes and ABducts the 1st metacarpal at the 1st carpometacarpal joint, flexes both phalanges of the Pollux
Where does the Pronator Quadratus attach and what does it do?
It attaches on the distal ulna and distal radius
It pronates the forearm and holds the ulna and radius together
What muscles are part of the superficial layer of EXTENSORS?
Brachioradialis, Extensor Carpi Radialis Longus, Extensor Digitorum, Extensor Digiti Minimi, and Extensor Carpi Ulnaris
What are Brachioradialis and Extensor Carpi Radialis Longus innervated by?
Radial N
What is Extensor Carpi Radialis Longus innervated by?
Deep Radial N
What innervates Extensor Digitorum, Extensor Digiti Minimi, and Extensor Carpi Ulnaris?
Posterior Interosseous Nerve
Where do Brachioradialis and Extensor Carpi Radialis Longus originate?
Lateral Humeral Supracondylar Ridge
Where do Extensor Carpi Radialis Brevis, Extensor Digitorum, Extensor Digiti Minimi, and Extensor Carpi Ulnaris originate from?
Lateral Humeral Epicondyle
Where does Extensor Carpi Radialis insert and what does it do?
It inserts to the base of the 2nd metacarpal
It extends and ABducts the hand at the wrist
Where does Extensor Carpi Radialis Brevis insert and what does it do?
The base of the 3rd metacarpal
It extends and ABducts the hand at the wrist
Where does Extensor Digitorum insert and what does it do?
It inserts into the Extensor expansions of digits 2-5
It extends the hand at the wrist, extends all phalanges of digits 2-5
Where does Extensor Digiti Minimi insert and what does it do?
It inserts in to the extensor expansion of digit 5
It extends all phalanges of digit 5
Where does Extensor Carpi Ulnaris insert and what does it do?
It inserts into the base of the 5th metacarpal
It extends and ADducts the hand at the wrist
What are the deep extensor muscles and what are they innervated by?
Supinator: Deep Radial N.
Extensor Indicis: Posterior Interosseous N.
What do the deep extensor muscles do and where do they respectively attach?
Supinator: Attaches between the lateral humeral epicondyle, ligaments of the elbow, and the proximal aspect of the radial body
It supinates the forearm
Extensor Indicis: Attaches between the distal ulna and the extensor expansion of digit 2
It extends the hand at the wrist and extends the 2nd digit
What are the outcropping muscles of the deep layer of extensors and what are they all innervated by?
Abductor Pollicis Longus, Extensor Pollicis Longus, and Extensor Pollicis Brevis
Posterior Interosseous N.
Where does the Abductor Pollicis Longus attach and what does it do?
It attaches on the proximal ulna and radius to the base of the 1st metacarpal
It ABducts the hand at the wrist, ABducts the Pollux
Where does the Extensor Pollicis Longus attach and what does it do?
It attaches at the posterior aspect of the ulna to the base of the distal phalanx of the Pollux
It ABducts the hand at the wrist, extends 1st metacarpal and the proximal and distal phalanges of the Pollux
Where does the Extensor Pollicis Brevis attach and what does it do?
It attaches to the posterior aspect of the radius to the base of the proximal phalanx of the Pollux
It ABducts the hand, Extends the 1st metacarpal and proximal phalanges of the Pollux
What muscles make up the Thenar Eminence?
Abductor Pollicis Brevis, Opponens Pollicis, Flexor Pollicis Brevis, and Adductor Pollicis
Where does the Abductor Pollicis Brevis attach and what does it do?
It attaches to the scaphoid, trapezium, and flexor retinaculum to the base of the proximal phalanx of the Pollux
It ABducts the Pollux and aids in opposition
Where does the Opponens Pollicis attach and what does it do?
It attaches to the scaphoid, trapezium, and flexor retinaculum to the 1st metacarpal
It opposes the Pollux
What does Flexor Pollicis Brevis attach to and what does it do?
It attaches to the scaphoid, trapezium, and flexor retinaculum to the base of the proximal phalanx of the Pollux
It flexes the 1st Metacarpal and Proximal phalanges of the Pollux
Where does Adductor Pollicis attach and what does it do?
Transverse head: body of 3rd metacarpal to the proximal phalanx of the Pollux
Oblique Head: capitate and base of 2nd and 3rd metacarpals to proximal phalanx of the Pollux
It ADducts the Pollux
What innervates Abductor Pollicis Brevis and Opponens Pollicis?
Recurrent Branch of the Median N.
What innervates Adductor Pollicis?
Deep Ulnar N.
What innervates Flexor Pollicis Brevis?
Superficial Head: Recurrent Branch of the Medial N.
Deep Head: Deep Ulnar N.
What muscles are part of the Hypothenar eminence and what are they innervated by?
Abductor Digiti Minimi, Flexor Digiti Minimi Brevis, and Opponens Digiti Minimi
Deep Ulnar N.
Where does Abductor Digiti Minimi attach to and what does it do?
Pisiform to base of proximal phalanx of 5th digit
ABduct 5th digit
Where does Flexor Digiti Minimi Brevis attach and what does it do?
Attaches from the Hamate hook to the base of the proximal phalanx of the 5th digit
It flexes the proximal phalanx of the 5th digit
Where does Opponens Digiti Minimi attach and what does it do?
It attaches from the hamate hook to the medial aspect of the 5th metacarpal
It opposes the 5th digit
What groups of muscles are the intermediate muscles in the hand?
Lumbricals, DABs, and PADs
Action and Innervation for 1st and 2nd Lumbricals?
Action: Flex proximal phalanges of the 2nd and 3rd digits, extend intermediate and distal phalanges of 2nd and 3rd digits by tightening extensor expansion
N: Median N.
Action and Innervation for 3rd and 4th Lumbricals?
Action: Flex proximal phalanges of the 4th and 5th digits, extend intermediate and distal phalanges of the 4th and 5th digits by tightening extensor expansion
N: Deep Ulnar N
Action and Innervation of DABs?
Action: ABduct digits 2-4, flex proximal phalanges, extend intermediate and distal phalanges
N: Deep Ulnar N.
Action and Innervation of PADs?
Action: ADduct 2nd, 4th, and 5th digits, flex proximal phalanges of the 2nd, 4th, and 5th digits, and extend intermediate and distal phalanges of the 2nd, 4th, and 5th digits
N: Deep Ulnar N.
