I Can't Feel My Hand.

When your hand falls asleep, feels numb, tingles or simply does not feel quite right, it can be unsettling. In many cases the cause is compression of a nerve that travels from your neck down your arm to your hand.

The nerves that bring feeling to the hand pass through narrow tunnels along the way. When those tunnels become tight or the nerve gets irritated, it cannot send signals normally — which is exactly when you feel numbness, tingling, burning or weakness.

Which Nerve Is Affected?

Where you lose feeling gives an important clue about which nerve is involved.

• Carpal tunnel syndrome — numbness or tingling in the thumb, index, middle and part of the ring finger, from compression of the median nerve at the wrist. Often worse at night.
• Cubital tunnel syndrome — numbness or tingling in the ring and small fingers, from compression of the ulnar nerve near the elbow.
• Pressure on the ulnar nerve at the wrist (Guyon's canal) can also affect the ring and small fingers.
• Nerve irritation higher up, such as in the neck, can cause symptoms that extend into the hand.

Why It Matters

Feeling is part of how your hand knows where it is in space and how firmly it is gripping. Long-standing nerve compression can also lead to weakness over time, so persistent numbness should not be ignored.

Getting an Evaluation

A hand and upper-extremity surgeon can evaluate the pattern of your symptoms, examine the relevant joints and nerves, and, when needed, use nerve conduction studies to pinpoint the level of compression. Understanding the cause guides the right treatment — from activity and positioning changes to splinting, therapy, injections or, in appropriate cases, surgical nerve decompression.

If your hand feels numb, tingles or has lost feeling, an evaluation can help you understand what is going on and whether it can be treated.