Arm and Cubital Fossa

Question 1

Review Osteology and Articular surfaces

Answer 1

Carpal articular surfaces
Humeroradial
Humeroulnar
proximal radioulnar

Question 2

Important Veins

Answer 2

Cephalic Vein

Basilic Vein

Question 3

Important Nerves

Answer 3

Brachial Plexus
Supraclavicular Nerves
Intercostobrachial Nerve T2 (heart attach nerve)
Posterior Cutaneous Nerve of Arm
Posterior Cutaneous Nerve of Forearm
Medial Cutaneous Nerve of Arm
Lateral Cutaneous Nerve of forearm

Question 4

Dermatomes

Answer 4

Brachial Plexus:

C5, 6, 7, 8
T1

Question 5

Dermatome Vs. Myotome

Answer 5

D: area of skin supplied w/ afferent nerve fibers by a single posterior spinal root

M: all muscles innervated by a single efferent ant. root Most muscles have more than one myotome

Question 6

Brachial Fascial

Answer 6

Lateral and Medial Intermuscular septa
Median Nerve Medial w/ brachial artery and veins
Ulnar Nerve w/ collateral veins inferior to median nerve
Radial nerve w/ collateral arteries and veins lateral and inferior to brachialis

Question 7

Vasculature of the arm

Answer 7

Axillary a. > Brachial a.
Brachial breaks to 3 arteries

Profunda Brachii (deep brachial) artery: 2 branches
middle collateral
radial collateral

Superior ulnar collateral

Inferior ulnar collateral

Question 8

Musculature of the Arm Flexors

Answer 8

Biceps Brachii (long and short head)
Brachialis
Coracobrachialis

Question 9

Biceps Brachii

Answer 9

Origin: Long head supraglenoid tubercle of scapula
Short head coracoid porcess of scapula

Insertion: radial tuberosity & fascia of forearm via bicipital aponeurosis

Axns: supinate forearm
flex forearm (when supine)
Short head resists dislocation of shoulder

Blood: Brachial artery

Nerve: musculocutaneous nerve (C5, 6)

Question 10

Musculature of Arm Extensors

Answer 10

Triceps Brachii

Aconeus

Question 11

Coracobrachialis

Answer 11

Origin: coracoid process of scapula

Insertion: middle 1/3 of medi. humeral surface

Axns: flexes and adducts arm at shoulder
Resistis dislocation of shoulder joint

Blood: brachial artery

Nerve: musculocutaneous nerve (C5, 6, 7)

Question 12

Brachialis

Answer 12

Origin: distal 1/2 of ant. surface of humerus

Insertion: coronoid process and tuberosity of ulna

Axns: flexes forearm at elbow joint

Blood: brachial artery

Nerve: musculocutaneous nerve C5, 6

Question 13

Aconeus

Answer 13

Origin: lateral epicondyle of humerus

Insertion: lat. surface of olecranon:
superior surface of ulna

Axns: assists triceps in extension of forearm
stabilizes elbow joint

Blood: deep brachial artery

Nerve: radial nerve ( C7, 8, T1)

Question 14

Triceps Brachii

Answer 14

Origin: Long: infraglenoid tubercle
Lateral: post. surface of humerus
Medial: post. surface of humerus, infer. to radial groove

Insertion: prox. end of olecranon and fascia of forearm

Axns: extends forearm at elbow
Resists dislocation of shoulder joint (long head)

Blood: deep brachial artery

Nerve: Radial nerve (C6, 7, 8)

Question 15

Cubital Fossa: Subcutaneous structures:

Answer 15

Cephalic Vein

Basilic Vein (gives rise to median cubital vein)

Inferior ulnar collateral a.

ulnar n

musculocutaneous n

radial a

Question 16

Cubital Fossa: Boundaries

Answer 16

Lateral: brachioradialis

Medial: pronator teres

Superior: an imaginary line between medial and lateral epicondyles of humerus

Roof: skin, superficial and deep fascia, bicipital aponeurosis

Floor: supinator and brachialis

Question 17

Contents of Cubital Fossa

Answer 17

Median Nerve

Bifurcation of radial and ulnar arteries

Brachial veins

Tendon of Biceps brachii and bicipital aponeurosis

Radial Nerve
deep and superficial branches

Question 18

Elbow Region

Answer 18

Triceps and Olecranon Process

anconeus

ulnar nerve runs posterior to medial epicondyle of humerus

posterior ulnar recurrent artery

Question 19

Cubital Anastomosis

Answer 19

Brachial artery - Ulnar artery
superior ulnar collateral - posterior ulnar recurrent
inferior ulnar collateral - anterior ulnar recurrent

Deep Brachial Artery - Radial and Interosseous Arteries
Radial Collateral artery - Radial recurrent artery
Middle collateral artery - interosseous recurrent artery