Arm (Brachium) Flashcards
name the muscles of the anterior compartment of the arm
biceps brachii
coracobrachialis
brachialis
what nerve innervates the muscles of the anterior compartment of the arm?
musculocutaneous n
name the muscles of the posterior compartment of the arm
triceps brachii
what nerve innervates the muscles of the posterior compartment of the arm?
radial n
the medial intermuscular septum of the arm contains what structures?
median n
ulnar n
brachial a
the lateral intermuscular septum contains what structures?
radial n
profunda brachii a
origin of biceps brachii
long head: supraglenoid tubercle of scapula
short head: coracoid process of scapula
insertion of biceps brachii
radial tuberosity
innervation & spinal level of biceps brachii
musculocutaneous n (C6)
actions of biceps brachii
- forearm supination
- simple forearm flexion when elbow extended and forearm supinated
- long head = stabilizer of glenohumeral joint
what nerve root is associated with the deep tendon reflex of biceps brachii?
C5
origin & insertion of coracobrachialis
O: coracoid process, scapula
I: medial surface of middle humerus
innervation & spinal levels of coracobrachialis
musculocutaneous n (C6)
action of coracobrachialis
flex & adduct humerus at glenohumeral joint
origin & insertion of brachialis
O: distal half of anterior humerus (where coracobrachialis ends)
I: ulnar tuberosity & anterior surface of coronoid process
innervation & spinal levels of brachialis
musculocutaneous n (C6, sometimes C7 from radial n)
action of brachialis
- flex forearm at elbow in any position
- controlled relaxation during extension of forearm to gently place object down
musculocutaneous nerve lies deep to ____ and superficial to ____
biceps brachii
brachialis
peripheral entrapment sites of musculocutaneous n
- coracobrachialis (n pierces through)
- space between biceps brachii & brachialis
symptoms of peripheral entrapment of musculocutaneous n
- lateral forearm paresthesia (occurs first)
- weak supination & flexion
peripheral entrapment sites of lateral antebrachial cutaneous n
biceps brachii & brachialis (where it exits)
symptoms of peripheral entrapment of lateral antebrachial cutaneous n
lateral forearm paresthesia without weakness (no motor function here)
name the 3 branches off the brachial artery
profunda brachii a
superior ulnar collateral a
inferior ulnar collateral a
the brachial artery is a continuation of the ____ after it passes the ____
axillary a
teres major
the artery that runs with the radial nerve is the ____
profunda brachii a
the artery that branches off the middle of the brachial artery and runs with the ulnar nerve is the ____
superior ulnar collateral a
superior ulnar collateral artery runs with what nerve?
ulnar n
superior ulnar collateral artery anastomoses with ____
posterior ulnar recurrent a
(superior ulnar collateral a runs with ulnar n through groove on posterior side)
radial collateral artery anastomoses with ____
radial recurrent a
what artery runs anterior to the medial epicondyle?
inferior ulnar collateral a
inferior ulnar collateral artery anastomoses with ____
anterior ulnar recurrent a
the brachial artery runs with what nerve?
median n
origins of triceps brachii
long: infraglenoid tubercle, scapula
lateral: posterolateral surface of humerus & lateral intermuscular septum
medial: posteromedial surface of humerus & medial intermuscular septum
insertion of triceps brachii
olecranon process, ulna
innervation & spinal levels of triceps brachii
radial n
C7, C8
actions of triceps brachii
- extend forearm at elbow
- long head stabilizes GH joint and extends humerus at GH joint
triceps brachii is associated with what nerve root reflex?
C7
moving proximally up the arm, the brachial vein dumps into the ____ vein, which then dumps into the ____ vein
basilic v
axillary v (crosses teres major)
moving proximally up the arm, the cephalic vein passes through the ____ and dumps into the ____ vein
deltopectoral triangle
axillary v
the cephalic vein runs along the ____ side of the arm
lateral
the basilic vein runs along the ____ side of the arm
medial
the basilic vein runs with what nerve superficial to the cubital fossa?
medial antebrachial cutaneous n
what vein connects the cephalic to the basilic vein?
median cubital vein
the cephalic vein runs with what nerve superficial to the cubital fossa?
lateral antebrachial cutaneous n
what structure forms the floor of the cubital fossa?
tendon of brachialis m
what structure forms the base of the cubital fossa?
line between lateral and medial epicondyles
what structure forms the roof of the cubital fossa?
bicipital aponeurosis
what structure forms the lateral border of the cubital fossa?
brachioradialis m
what structure forms the medial border of the cubital fossa?
pronator teres m
what are the contents of the cubital fossa?
brachial v
median n
brachial a
describe the orientation of the radial nerve through the upper arm
begins posterior, runs posterolateral, then anterolateral along spiral groove of humerus
the radial nerve separates what 2 muscles lateral to the cubital fossa?
brachioradialis & brachialis
describe the path of the radial nerve as it approaches the cubital fossa
travels lateral to cubital fossa, branches into deep & superficial branches of radial n
name the potential entrapment sites of the radial nerve in the arm
- at the spiral groove
- between brachioradialis & brachialis