Lecture 3 - Muscles Of The Upper Arm

Question 1

What can the arm be referred to as?

Answer 1

• the brachium

Question 2

What is the biceps brachii?

Answer 2

• Superficial on anterior arm
• Biceps = “two heads”

Question 3

What is the origin of the biceps brachii (long/short head)?

Answer 3

• Long head (lateral) - supraglenoid tubercle of scapula
• Short head (medial) - coracoid process of scapula

Question 4

What is the insertion/Innervation of the biceps brachii?

Answer 4

• I: Radial tuberosity
• Inn: Musculocutaneous nerve

Question 5

What is the main actions of the biceps brachii?

Answer 5

• Radio-ulnar (forearm) supination
• Elbow & Shoulder flexion

Question 6

What is the origin/insertion/Innervation/main action of the brachialis ?

Answer 6

• O: Anterior humerus 1/3 down the shaft
• I: Ulnar tuberosity & coronoid process of the ulna
• Inn: Musculocutaneous nerve
• MA: Elbow flexion

Question 7

What is the origin/insertion/Innervation/main action of the coracobrachialis?

Answer 7

• O: Coracoid process of scapula
• I: Medial shaft of humerus (mid shaft)
• Inn: Musculocutaneous nerve
• MA: Shoulder flexion & adduction

Question 8

What is the origin of the triceps brachii (long/lateral/medial heads)?

Answer 8

• Long head - infraglenoid tubercle of the scapula
• Lateral head - greater tubercle on the posterior humerus
• Medial head - posterior humerus shaft

Question 9

What is the insertion/Innervation of the triceps brachii?

Answer 9

• I: Olecranon process of the ulna
• Inn: Radial nerve

Question 10

What is the main actions of the triceps brachii?

Answer 10

• Elbow extension
• Shoulder extension (long head only)

Question 11

What is the origin/insertion/Innervation/main action of the anconeus ?

Answer 11

• O: Lateral epicondyle of the humerus
• I: Olecranon process of the ulna
• Inn: Radial nerve
• MA: Elbow extension