Symptoms · Wrist
A lump on the back of the wrist
The short answer
A round lump on the back of the wrist that may change in size and sometimes aches with use is usually a ganglion cyst: a harmless sac of fluid connected to a joint or tendon. It often shrinks or goes away by itself. If it hurts, limits movement, causes numbness, or bothers you, it can be removed under local anaesthesia. See a doctor if the lump is hard, grows quickly, or your hand is numb or weak.
How patients describe it
- A bump on the back of my wrist
- A lump that changes in size
- Wrist ache when I use my hand
- A lump after repeated wrist strain
- Tingling in my fingers
See a doctor soon if you have
- Numbness, tingling or weakness in the hand
- A hard lump that grows quickly
- Redness, heat or fever
- A lump after an injury, with severe pain or a deformed wrist
- Loss of finger movement
What can cause it
Ganglion cyst
A smooth, round lump that may change in size, sometimes aching with use.
Next step: Examination; watching it is a safe choice.
Tendon sheath swelling
A swelling along a tendon, with pain when you move the wrist or fingers.
Next step: Rest and examination; see a doctor if it persists.
Bony bump (carpal boss)
A hard, fixed bump on the back of the hand that does not change in size.
Next step: Examination and an X-ray.
Arthritis or another lump
Stiffness and pain in the joint, or an uncommon lump such as a lipoma.
Next step: Examination, ultrasound or MRI.
What you can do now
- Rest the wrist and avoid repeated strain
- A wrist support can make it more comfortable
- Do not hit the lump with a book or heavy object; it can injure the wrist and the lump often returns
- Note changes in size, pain and numbness, and tell the doctor
Tests your doctor may order
- Examination of the wrist and hand
- Ultrasound or an MRI scan if the diagnosis is unclear
When is surgery needed?
- Many ganglia need no treatment.
- A ganglion that hurts or limits movement can be removed under local anaesthesia, and fasting is not required. The waterproof dressing lets you shower. It comes back in about 5–10 in 100 people.
Related operation guides
Questions people ask
Will it go away by itself?
Many shrink or disappear. Some stay the same size, and this is harmless if there is no pain or numbness.
Is it cancer?
No. A ganglion is a fluid-filled sac. Any hard lump that grows quickly should still be checked.
Will it come back after surgery?
It can, in about 5–10 in 100 people.
This page gives general information and does not replace the advice of your treating team. In an emergency, go to the nearest emergency room.