Carpal tunnel syndrome causes symptoms in one or both hands that, more rarely, may also extend up the arm. Symptoms are caused by compression of the median nerve in the carpal tunnel. This nerve supplies feeling to the thumb, index, middle, and half the ring finger. It also innervates the muscles that move the thumb toward the little finger and move the index finger around in a circle.

Symptoms include:

• Tingling, burning, or numbness, especially in your thumb and index or middle fingers
• Pain or numbness that worsens with:
  • Wrist, hand, or finger movement
  • Sleep (symptoms may wake you)
• Hand stiffness or cramping that gets better after:
  • Shaking the hand
  • Waking up in the morning
• Weakness or clumsiness of your hand
  • Loss of grip strength
  • Difficulty touching your little finger with your thumb
  • Frequently dropping things
• Pain extending up your arm