upper limb muscles Flashcards
sternocleidomastoid (SCM)
O:
- clavicular head: sternal end of clavicle
-Sternal head: manubrium
I: mastoid region of skull and lateral portion of superior nuchal line
A:
-together: felt the neck
-Individually: laterally flex/rotate head to opposite side
Innervation: accessory (cranial nn XI)
Strap muscles (infra hyoids) (action only)
- Sternohyoid
- Thyrohyoid
- Sternothyroid
- omohyoid
action: depress the hyoid
Suprahyoid Muscles (action only)
- Diagastric (ant./post. belly)
- Mylohyoid
- Geniohyoid
5.Stylohyoid
(anterior neck)
Action: all elevate hyoid and depress mandible
Trapezius
O: occipital bone, ligament nuchae, spinous process of the T spine vertebrae
I: clavicle and scapula (acromion and scapular spine)
A: elevate, retract, depress rotate scapula upwards
Innervation: Accessory nerve
Scalene muscles (action only)
Posterior
Middle
Anterior
Action:
-Together: flexion
-Alone: lateral flexion, rib elevation
-Rotation: Ant. scalene; rotate opposite side
- Mid+Post; same side rotation
Latissimus Dorsi
O: spinous process of inferior thoracic and all lumbar/sacral vertebrae, ribs 8-12 and thoracolumbar fascia
I: Floor of inter tubercular sulcus of humerus
A: extends, adducts, med. rotates shoulder
N: thoracodorsal nerve
Levator scapula
O: Transverse process of first four C spine vertebrae
I: Vertebral border of scapula near superior angle and medial end of scapular spine
A: elevates scapula
N: cervical C3-C4 and dorsal scapular nerve
Rhomboid Major
O: ligamentum nuchae and SP of T2-T5
I: vertebral border of scapula from spine to inferior angle
A: adducts and performs downward rotation of scapula
N: Dorsal scapular nerve
Rhomboid Minor
O: SP of vertebrae C7-T1
I: vertebral border of scapula
A: adducts and downward rotation
N: dorsal scapular nerve
erector spinae (intermediate layer) (I love spaghetti)
iliocostalis
longissimus
spinalis
Action: together extension of back
Unilateral- neck lateral flexion, lateral flexion of spine
deep layer of posterior trunk (action only)
-multifidus
-rotatores
-interspinalis
-semispinalis
-intertransversarii- lateral flexion
Action: all extend vertebral column
rotatores, semispinalis, and multifidus also rotate to the opposite side
external oblique
O: external and inferior borders of ribs 5-12
-fibres run anterior and inferior
I: external oblique aponeurosis extending to iliac crest and linea alba
A: compresses, rotates opposite side
Internal oblique
O: thoracolumbar fascia, inguinal ligament and iliac crest
-fibres run anterior superior
I: inferior surfaces of ribs 9-12, costal cartilages 8-10, linea alba and pubis
A: compresses, rotates to same side
transverse abdominis
deep layer and compresses abdomen
rectus abdominis
O: superior surface of pubis around symphysis
I: inferior surfaces of cartilages ribs 5-7 and diploid of sternum
A: flexion of vertebral column, compression and depress ribs
N: intercostal nerve
-riight and left side superheated by linea alba
-contained within rectus sheath
intercostals (external, internal)
external- elevate ribs
internal- depress ribs
transverse thoracis- depress ribs
Diaphragm
innervated by phrenic nerve
C3, 4 and 5 keep me alive
contracts during inhalation- expands thoracic cavity
biceps brachii
O:
-short head: coracoid process
-Long head: supragelnoid tubercle on scapula
I: radial tuberosity
A: flexion at elbow and shoulder, supination of forearm and hand
N: musculocutaneous nerve C5-C6
Brachialis
O: distal half of anterior surface of humerus
I: Ulnar tuberosity and coronoid process
A: flexion at elbow
N: musculocutaneous C5-C6 and radial C7-C8
Brachioradialis
O: lateral supercondylar ridge of humerus (superior to lateral epicondyle)
I: lateral aspect of styloid process of radius
A: flexion at elbow
N: radial nerve C6-C8
Triceps Brachii
O:
-lateral head: superior lateral margin of humerus
-medial head: posterior surface inferior to radial groove
-Long head: infraglenoid tubercle of the scapula
I: olecranon process of ulna
A: extension of elbow
Long head also shoulder extension and adduction
N: radial C6-C8
Aconeus
O: posterior surface of lateral epicondyle of humerus
I: lateral margin of olecranon and ulnar shaft
A: extension of elbow
N: radial nerve C6-C8
Flexor Carpi radials
O: medial epicondyle of humerus
I: bases of second and third metacarpal
A: flexion and abduction
N: median nerve C6-C7
Flexor Carpi Ulnaris
O: medial epicondyle and anteromedial portion of ulna
I: pisiform, hamate, and base of fifth metacarpal
A: flexion and adduction of wrist
N: ulnar C8-T1
Palmaris Longus
O: medial epicondyle of humerus
I: palmar aponeurosis and flexor retinaculum
A: flexion of wrist
N: median nerve C6-C7
Digital Flexors (anterior compartment)
flexor digitorum profundus
(action)
flexion of wrist, DIP and PIP
Digital Flexors (anterior compartment)
flexor digitorum superficialis
(action)
flexion of wrist
MCP
PIP
Digital Flexors (anterior compartment)
flexor pollicis longus
(action)
flexion of thumb
Extensor Carpi Radialis Longus
O: lateral supracondylar ridge of humerus
I: base of second metacarpal bone
A: extension and abduction at wrist
N: radial nerve C6-C7
Extensor Carpi Radialis Brevis
O: lateral epicondyle of humerus
I: base of third metacarpal
A: extension and abduction at wrist
N: radial nerve C6-C7
Extensor Carpi Ulnaris
O: lateral epicondyle of humerus, dorsal surface of ulna
I: base of fifth metacarpal bone
A: extension and adduction at the wrist
N: deep radial nerve C6-C8
extensor digitorum (action)
extension of fingers and wrist
extensor pollicis longus (action)
extension at joints of thumb, abduction at wrist
extensor pollicis brevis (action)
extension at joints of thumb, abduction at wrist
extensor digiti minimi (action)
extension at joints of little finger, extension of wrist
abductor pollicis longus (action)
abduction at joints of thumb and wrist
extensor indicis (action)
extension and adduction at joints of index finger
pronator teres (long and thread like)
O: medial epicondyle of humerus and coronoid process of ulna
I: middle or lateral surface of radius
A: pronate forearm and hand
N: median nerve C6-C7
Pronator quadratus (wrist watch)
O: anterior and medial surface of distal ulna
I: anterolateral surface of distal portion of radius
A: pronation (medial rotation of radius)
N: median nerve C8-T1
supinator
O: lateral epicondyle of humerus and ridge near radial notch of ulna
I: anterolateral surface of radius distal to the radial tuberosity
A: supinates forearm
N: deep radial nerve C6-C8
