Arm muscles Flashcards
Anterior arm Posterior arm Formatives for pectoral girdle and arm
Which head of the biceps arise from coracoid process along with coracobrachialis
Short head of biceps
Origin: long head of biceps
Course in humerus
Supraglenoid tubercle
Runs in bicipital groove of humerus
Attachment of tendon of biceps on radius
Radial tuberosity
Action of biceps on shoulder and elbow joint
Action of biceps on radio ulnar joint
Flexion of shoulder and elbow joint
Supinator of radio ulnar joint
BBC nerve supply - anterior arm muscles
From which cord does this nerve arise from the brachial plexus
Musculocutaneous nerve
Lateral cord
Which segmental fibers mainly innervate biceps brachii
Musculocutaneous nerve -segmental root values
Course in the forearm
C5, C6
C5-C7
Continues as lateral cutaneous nerve in forearm
Coracobrachialis
Action on shoulder [2]
Nerve supply
Flexion and adduction (shoulder)
Musculocutaneous nerve
Brachialis
Action [1]
Nerve supply
Elbow flexion
Musculocutaneous nerve
How can u identify musculocutaneous nerve on cadaver [2]
Perforates coracobrachialis
Descends between biceps and brachialis
Axillary artery - when does it become brachial artery
End point of brachial artery
Where it divides into
Relation of brachial artery and profunda brachii
Begins at lower border of trees major
Ends in cubital fossa
Where it divides into radial and ulnar arteries
Profunda brachii is one of the main branches of brachial artery
Median nerve
Arises from 2 cords of brachial plexus
Which artery does it closely follow in the arm
Lateral and medial cord of brachial plexus
Median nerve follows brachial artery closely
Ulnar nerve
Which cord of brachial plexus does it arise from
Which artery does it closely follow in the arm
NB It then enters the posterior compartment of arm by running along medial head of triceps and to the back of the medial epicondyle
Medial cord
Brachial artery
Clinical knowledge: What fractures can result in damage to Radial nerve [1] Ulnar nerve [1] Axillary nerve [1]
Fractures of…
Radial nerve - midshaft humeral fracture
Ulnar nerve - posterior part of medial epicondyle (radial head)
Axillary nerve - surgical neck of humerus fracture
Cubital fossa boundaries: Base of triangle Medial border Lateral border NB this is where the brachial artery ends - bifurcation into radial and ulnar artery
Base of triangle - a line drawn between 2 humeral epicondyles
Medial border- pronator teres
Lateral border - brachioradialis
Posterior arm Triceps Origin [2] but 3 heads Attachment Action [1]
Origin - humerus and infraglenoid tubercle
Attachment - olecranon
Action - elbow extension
Anconeus action
elbow extension
N supply to Anconeus and triceps
radial nerve
Radial nerve
Root values
Which branch of brachial artery accompanies radial nerve in radial groove
Which group of muscles are most likely to be affected by a mid shaft humeral fractures
C5-C8, T1
Profunda brachii
Extensor muscles of arm and forearm
Characteristic clinical sign of radial nerve injury
Wrist drop
2 collateral ligaments in ligaments of elbow joint: lateral and medial collateral ligament
Which ligament holds head of radius
Annular ligament
Supinator muscles [2]
Pronator muscles [2]
Supination
- Biceps brachii
- Supinator
Pronation
- Pronator teres
- Pronator quadratus
Innervation of teres minor
Axillary nerve
Infrapsinatus action on shoulder rotation
Lateral rotation
Main action of serrates anterior
Innervation
scapula protraction
long thoracic nerve
Type of joint
Acromioclavicular joint
superior Radioulnar joint
Acromioclavicular joint- synovial plane joint
superior Radioulnar joint - synovial plane joint
Name 3 muscles that insert into greater tubercle of humerus
Supraspinatus
Infraspinatus
Teres minor
Which nerve is closely related to medial epicondyle
Ulnar nerve
3 actions of lat dorsi
Shoulder extension
Shoulder adduction
Medial rotation
