Superficial & Osseous Upper Limb

Question 1

Hand digit numbering

Answer 1

Thumb is #1
Pinky is #5

More precise: thumb, index, middle, ring, and little.

Question 2

Arm vs forearm

Answer 2

Arm: between shoulder and elbow joints.
Forearm: between elbow and wrist, and can be called forearm or antebrachium

Question 3

Superficial fascia

Answer 3

• located deep from the skin and superficial from deep fascia
• loose CT, typically containing a large amount of fat.
• allows skin and other superficial structures to be mobile.
• serves as a conduit for superficial structures: superficial veins, superficial lymphatic vessels, cutaneous nerves.

Question 4

Superficial veins

Answer 4

• veins coursing within superficial fascia, often visible when looking at the skin surface. (As opposed to deep veins which lie deep from the deep fascia- or perforating veins which communicate between the superficial and deep veins)
• These superficial veins are often used for intravenous access or phlebotomy.

Question 5

Basilic vs Cephalic veins

Answer 5

Are named based on the limb being in an abducted thumbs-up position- with the cephalic located toward the head, and the basilic toward the “base”

Question 6

Basilic vein

Answer 6

Begins at the medial (ulnar) confluence of the dorsal venous network of the hand-ascends the forearm and arm predominately anteromedially (medial from the biceps brachii)-then passes through deep fascia near the junction of the inferior and middle thirds of the arm.
-Joins veins accompanying the brachial artery (venae comitantes)- to then begin the auxiliary vein.

Question 7

Cephalic vein

Answer 7

Begins at the lateral (radial) confluence of the dorsal venous network of the hand, crosses the anatomical snuffbox-ascends forearm and arm predominantly anterolaterally (lateral from the biceps brachii)-then at the clavipectoral triangle penetrates deep fascia to join the terminal portion of the auxiliary vein.
-At the cubical fossa, a communication often courses from the cephalic vein, medically, to join the basilic vein-called the median cubical vein.

Question 8

Superficial Lymphatics

Answer 8

-Arise from lymphatic plexuses in the skin throughout the hand. The vessels then travel somewhat with the superficial veins. Superficial lymph vessels are more numerous than deep lymph vessels.
-Some accompanying the basilic vein to enter cubical lymph nodes-located proximal to the medial epicondyle and medial to the basilic vein.
-Some accompanying the cephalic vein enter deltopectoral lumph nodes.
(Eventually, they all drink to deep auxiliary lymph nodes)

Question 9

Cutaneous nerves

Answer 9

• Representations along the upper limb follow a segmental pattern that is easy to recognize if the limb is in the “embryonic position” (abducted, with thumb superiorly)- thus, the lateral portion is more cranial than the medial portion.
• Cutaneous nerves have mixed their way through the brachial plexus (C5-T1) prior to distributing along the extremity- so they do not always follow this same segmental pattern as dermatomes.

Question 10

Dermatomes

Answer 10

Segmental distribution of individual spinal nerves along the limb.

• Maps vary amongst different sources.
• Thumb is consistently C6, index C7, and little finger C8. Posteriorly, in general, C6 will be lateral from the elbow, C7 near the elbow, and C8 medial from the elbow.

Question 11

Peripheral Cutaneous Nerve Distributions

1. Median nerve
2. Ulnar nerve

Answer 11

1. Associated with carpal tunnel syndrome.

2. Associated with ulnar nerve entrapment at the elbow.