Arm

Question 1

Posterior surface of humerus

Answer 1

Superiorly marked by linear roughening for attachment of lateral head of triceps brachii, passing diagonally inferiorly to deltoid tuberosity

Middle part - radial groove (parallel to posterior margin of deltoid tuberosity). Radial nerve and profunda brachii artery lie in this groove

Question 2

Anterior compartment of arm

Answer 2

Coracobrachialis
Biceps brachii
Brachialis

Question 3

Coracobrachialis

Answer 3

Origin: coronoid process
Insertion: Midshaft of humerus on medial side
Flexor of forearm
Innervated by musculocutaneous nerve

Question 4

Biceps brachii

Answer 4

Origin: long head - supraglenoid tubercle, short head - coronoid process
Insertion: Radial tuberosity
Flexor of forearm, strongest supinator of arm when flexed
Innervated musculocutaenous nerve

Question 5

Brachialis

Answer 5

Origin - Anterior aspect of humerus (medial and lateral surfaces)
Insertion: ulna tuberosity
Innervated by musculocutaneous nerve, small component innervated by radial nerve
Flexor of forearm
Deep to biceps brachii

Question 6

Posterior compartment of arm

Answer 6

Triceps brachii

Question 7

Triceps brachii

Answer 7

3 heads 
Long head - infraglenoid tubercle
Medial and lateral head - posterior surface of humerus
Insertion: olecranon
Innervated by radial nerve
Extensor of forearm

Question 8

Brachial artery

Answer 8

Continuation of axillary artery beneath teres major
In proximal arm, lies on the medial side.
In the distal arm moves laterally to be midway between lateral epicondyle and medial epicondyle
At elbow joint, lies medial to tendon of biceps brachii.
Branches into radial and ulnar artery

Question 9

Basilic vein

Answer 9

Lies medial to brachial artery

Brachial veins join basilic or axillary vein

Question 10

Musculocutaneous nerve

Answer 10

Passes through coracobrachialis muscle
Passes in between biceps brachii and brachialis
Emerges laterally to tendon of biceps brachii at elbow, and continues as lateral cutaneous nerve of forearm

Question 11

Median nerve

Answer 11

Passes vertically down medial side of arm in anterior compartment
Proximal region - median nerve lateral to brachial artery
Distally - median nerve medial to brachial artery
Has no branches in arm, but branch to pronator teres may originate from the nerve immediately proximal to the elbow joint

Question 12

Ulnar nerve

Answer 12

Passes through proximal regions medial to axillary artery
Middle of arm lis anterior to medial head of triceps brachii
Passes posterior to medial epicondyle
No major branches in arm

Question 13

Radial nerve

Answer 13

As it enters arm, lies posterior to brachial artery, then enters posterior compartment through triangular interval

Posteriorly lies in radial groove - diagonally from medial to lateral, between medial and lateral heads of triceps brachii
Enters anterior compartment where it lies between brachialis and brachioradialis (which attaches to lateral epicondyle of humerus)
Enters forearm anterior to lateral epicondyle of humerus, just deep to brachioradialis.

Question 14

Branches of radial nerve in arm

Answer 14

Muscular and cutaneous branches
Muscular to triceps brachii, brachioradialis, and extensor carpi radialis longus + lateral part of brachialis
Cutaneous - inferior lateral cutaneous nerve of arm and posterior cutaneous nerve of forearm (both pierces through lateral head of triceps brachii to be subcut)

Question 15

Cubital fossa borders

Answer 15

Brachioradialis muscle from lateral supraepicondylar ridge of humerus
Pronator teres from medial epicondyle of humerus
Base - imaginary line between medial and lateral epicondyle
Floor - brachialis

Question 16

Content of cubital fossa

Answer 16

From lateral to medial
Tendon of biceps brachii
brachial artery - bifurcates into radial and ulnar artery in the apex of fossa
median nerve - passes between ulnar and humeral heads of pronator teres

Brachial artery and median nerve protected anteriorly by bicipital aponeurosis

Ulnar nerve does not pass through cubital fossa

Question 17

Radial nerve at elbow joint

Answer 17

Lies just under hip of brachioradialis (which forms lateral margin of fossa). Here divides into superficial and deep branches:

1. superficial continues into forearm just deep to brachioradialis
2. deep passes between two heads of supinator to access posterior compartment of forearm

Question 18

Roof of cubital fossa

Answer 18

Formed by superficial fascia and skin
Most important structure = medial cubital vein which connects cephalic (laterally) and basilic (medially)
Other structures - medial cutaneous and lateral cutaneous