Arm and Brachial Musculature Flashcards
The lateral surface of the scapula supports an ovoid articular surface, the ___ fossa
glenoid
Roughened muscle attachment sites are located immediately superior (______ tuberosity) and inferior (______ tuberosity) to the glenoid fossa
supraglenoid; infragelnoid
The glnenoid fossa is extended laterally by a rim of fibrocartilage called the ___ ____
glenoid labrum
The tendon of the long head of ___ ____ integrates with the superior margin of the glenoid labrum as it passes through the glenohmeral joint to insert on the supraglenoid tuberosity
biceps brachii
The synovial membrane of the glenohumeral joint anchors medially on the outer margin of the glenoid labrum, and laterally along the anatomical neck of the humerus. There are three specializations of this synovial system. What are they?
- the synovial membrane is expansive inferiorly, forming the axillary recess
- the synovial membrane extends along the tendon of the long head of biceps brachia all the way into the intertubercular groove. In this way the membrane forms a lubricating sheath around this tendon preventing it from abrading against bone
- the synovial membrane evaginates anterosuperiorly forming the subtendinous bursa of the subscapularis
The coracohumeral ligament spans form the ___ of the coracoid process along the superior surface of the glenohumeral joint to the ___ ____
base; greater tubercle
This ligament attaches to the lesser and greater tubercles, spanning the intertubercular groove and functioning to prevent bowstringing of the tendon of biceps brachii
transverse humeral ligament
____ bursa is located immediately inferior to the accordion process and immediately superior to the tendon of supraspinatus
subacromial
The subacromial bursa is continuous distally with a second bursa, the ___ bursa, located superior to glenohumeral joint and greater tubercle and inferior to the deltoid
subdeltoid
Where is the subtendinous bursa of the subscapularis located?
anterior to the subacromial bursa, deep to the coracoid process and superficial to the tendon of subscapularis
This muscle is large, superficial, shaped like an inverted triangle and forms the rounded eminence of the shoulder
deltoid
what are the attachments of the deltoid
arises proximally from the lateral 1/3 of the clavicle, acromion, and spine of scapula to insert distally into the deltoid tuberosity of the humerus
what innervates the deltoid
axillary nerve
what are the actions of the deltoid?
entire muscle abducts arm from 15 to 120 degrees; anterior part flexes and medially rotates arm; posterior part extends and laterally rotates arm
The integrity of the proximal radioulnar joint is maintained by the ___ ligament which is attached to the superior margin of the radial notch, loops around the head and neck of the radius, then attaches to the inferior margin of the radial notch and the posterior surface of the ulna
annular
Dislocation of the radiulnar joint due to freeing of the annular ligament is called “____” elbow
nursemaid’s
note: happens with sharp jerks of the hand or forearm in children
The ulnar collateral ligament has three bands. Name and describe each
- anterior band: thickest, connects the medial epicondyle to the tubercle located on the medial surface of the coronoid process
- posterior band: broad, thin, sheet-like ligament spanning from the medial epicondyle to the medial margin of the olecranon
- oblique band: connects the distal tip of the medial olecranon to the tubercle on the medial surface of the coronoid process, runs from one portion of the ulna to another but crosses and strengthens the humeroulnar joint
Flexion of the elbow ____ the angle between the arm and forearm
decreases
Flexion of the elbow is achieved by the actions of ___ and ___ ___
brachialis; biceps brachii
Extension of the elbow is achieved by the actions of ___ ____ and ____
triceps brachii; anconeus
during extension, the radius moves ____, no extensor muscle inserts on the radius
passively
What is pronation of the forearm?
rotation of the forearm such that the palmar surface of the hand faces posteriorly
pronation of the forearm is achieved by the actions of ____ ___ and ____ _____
pronator teres; pronator quadratus
What is supination of the forearm?
rotation of the forearm such that the palmar surface of the hand faces anteriorly
Supination of the forearm is achieved by the actions of ____ ____ and ____
biceps brachii; supinator
The deep fascia of the arm is the ___ fascia
brachial
This muscles is large, three-headed and located on the posterior arm
triceps brachii
Give the origins of the long, lateral, and medial heads of triceps brachii
long head: infraglenoid tubercle of scapula
lateral head: humerus, proximal and lateral to th eradial groove and from the lateral intermuscular septum
medial head: from the humerus, distal and medial to the radial groove and from the medial intermuscular septum
What is the insertion of the triceps brachia?
the three heads converge onto a single strong tendon which inserts on the olecranon process of the ulna. The subtendinous olecranon bursa protects this tendon from the rough surface of the olecranon
What is the action of triceps brachii
extension of forearm
note: the medial head is active in all phases of extension , while the other two heads are recruited when extra power is needed
What innervates triceps brachia?
radial nerve
What is the vascular supply of triceps brachia?
profunda brachii (deep brachial) artery
The ___ head of triceps brachia weaves between teres major and teres minor producing the quadrangular space, triangular space, and triangular interval
long
This muscle is a small, triangular muscle on posterolateral aspect of elbow
anconeus
What is the origin of anconeus?
the lateral epicondyle of the humerus
What is the insertion of the anconeus?
olecranon and adjacent shaft of ulna
What is the action of anconeus?
assists in extending the forearm and stabilizing the elbow joint and joint capsule
What innervates anconeus?
radial nerve
What is the vascular supply of anconeus?
profunda brachii artery and recurrent interosseus artery
this muscle is short, slender, and in the proximal, medial portion of the arm
coracobrachialis
What is the origin of coracobrachialis?
coracoid process
What is the insertion of coracobrachialis?
medial surface of mid humerus
What is the action of coracobrachialis?
assits in flexion and adduction of the arm at the shoulder joint
What innervates coracobrachialis?
musculocutaneous nerve
What is the vascular supply of coracobrachialis?
brachial artery
___ is a flat, broad, strap-like muscle on the arm that acts as the primary flexor of the forearm/elbow
brachialis
What is the origin and insertion of brachialis?
origin: distal half of anterior surface of the humerus
insertion: the ulnar tuberosity and coronoid process of the ulna
What is the innervation and vascular supply of brachialis?
innervation: musculocutaneous nerve
vascular supply: raidal recurrent artery
___ ___ is a long, fusiform muscle with two heads, separated proximally that acts as the most powerful supiantory and also flexes the forearm/elbow and flexes, abducts the arm
biceps brachii
origin of short and long head of biceps brachii
short head: coracoid process
long head: supraglenoid tubercle
The bicipitoradial bursa protects the tendon of biceps brachii from what?
abrasion from the tuberosity
the bicipital aponeurosis arises as a wide, thin tendinous sheet. it sweeps inferomedially and memes with what fascia?
antebrachial
What innervates the biceps brachii?
musculocutaneous nerve
What is the vascular supply of biceps brachii?
brachial artery
