Superficial veins of upper limb
Most of the blood from the palm of the hand passes through to a superficial venous network on the dorsum. From the radial side of this arch the cephalic vein begins in the anatomical snuffbox and runs up along the preaxial border of the limb. It runs in the upper arm lateral to biceps, in the deltopectoral groove, and perforates the clavipectoral fascia to drain into the axillary vein. From the ulnar side of the dorsal venous arch the basilic vein runs up the postaxial border of the limb. It pierces the deep fascia halfway between elbow and axilla and joins the brachial veins to form the axillary vein.
The median forearm vein drains subcutaneous tissue of the front of the wrist and forearm. It divides at the elbow into median cephalic and median basilic, the latter receives a deep vein. These two veins open into the cephalic and basilic veins respectively. The deep communicating vein joins the median basilic vein and makes it a larger vessel than the median cephalic. The median cephalic is much less movable in the subcutaneous tissues than the median basilic, and therefore is often more convenient to use in intravenous therapy in spite of its smaller size. There are frequent variations from the standard patterns just described.