The Anatomy of the Basilic Vein

The basilic vein runs from the palm of the hand and up your arm on the side of the ulna (a long bone that extends from your elbow to your finger) and the pinky finger. The basilic vein is considered superficial because it’s near the surface of your skin. It’s often visible in the inner arm. 

This vein’s job is to drain blood out of the hand and arm on its way back to the heart. It’s sometimes used for various medical procedures, including vein punctures and transfusions.

Anatomy

Blood vessels—arteries, veins, and capillaries—take oxygen-rich blood from the heart and lungs, distribute it to all of your organs and tissues, and then return it to the heart and lungs for more oxygen. The basilic vein is responsible for draining oxygen-depleted blood from parts of the hand and arm.

Structure

In the back of your hand is a network of veins called the dorsal venous network of the hand. Dorsal means upper side or back. This network is made up of veins coming from the fingers, which are called the dorsal metacarpal veins.

Location

The basilic vein arises from the dorsal venous network. Veins from this network in the outer edge of the back of your hand curve slightly around your wrist and join together to become the basilic vein.

The basilic vein then runs up the outer edge of the inside of your arm, generally along the ulna. Along its course, other veins connect to it, including a branch from the cephalic vein called the median cubital vein, which joins with the basilic vein near the elbow.

The basilic vein continues traveling upward in a groove between the biceps brachii and pronator teres muscles. It crosses the brachial artery and runs up along the edge of the biceps brachii.

Just below the level of your axilla (armpit), the basilic vein travels deeper into your arm and joins with the brachial veins from the middle of your inner arm. Together, those veins become the axillary vein.

Anatomical Variations

While human anatomy has certain “standard” forms, not everyone is exactly the same. Variations in the paths of the veins do occur, and it’s important for healthcare providers to be aware of what variations they may encounter, especially during surgical procedures or while inserting a needle into your vein.

Studies have reported two common variations of the basilic vein, both of which have to do with the brachial veins at the point where they join the basilic. These variations are sometimes associated with variations of other veins as well. Some people may have a variation in one arm but not the other.

Function

The function of the basilic vein is to drain the blood from portions of your hand and arm so it can go back to the heart and lungs to be oxygenated and pumped out again.

The dorsal venous network of the hand drains the blood from the palm of your hand and sends it upward to the basilic vein. Small branches of the basilic vein transport blood from the arm as well. All of that is transferred to the axillary vein above the point where the basilic and brachial veins come together.

Clinical Significance

The basilic vein and other superficial veins of the arm are often used in medical procedures such as:

• Vein puncture for administering intravenous drugs or taking blood samples
• Transfusions of medication or blood
• Bypass graft, which involves taking a portion of the vein to repair another vein that’s damaged or diseased

The preferred site for these procedures is the inside of your elbow because of easy access to the veins and because it is relatively safe compared to other areas. The superficial veins running through there are obvious choices because they’re clearly visible.

However, among those veins, the basilic vein is considered the last choice. The better choices are the: 

• Medial cubital vein, which runs up the center of your inner arm and is usually highly visible
• Cephalic vein, which runs up the thumb side of your inner arm and is harder to see but farther from other important structures

The basilic vein is trickier to access because it’s closer to the brachial artery and the median nerve, which makes it more likely that a puncture will lead to an injury of one of those structures. In addition, the median cubital and cephalic veins are more stable, meaning they’re less able to move and roll away from the needle.

Summary

The basilic vein is responsible for taking blood that doesn’t have oxygen from the arms back to the heart and lungs, where it’s given oxygen again. While you can usually see it clearly, it’s considered a last resort in medical procedures. That’s because it’s close to important structures of the body that can potentially be injured and it’s less stable than the other two major veins in the arms.