What are ganglions (ganglion cysts)?
Ganglions are small sacs (cysts) filled with fluid that often appear as bumps on the hands and wrists. They can also develop on feet, ankles, knees, or shoulders. A ganglion can grow out of a joint capsule, which surrounds the joint, or a tendon sheath, which covers the tendon (the fibers connecting muscle to bone). Ganglions aren't cancerous.
Most people with ganglions notice that the bumps appear suddenly. Bumps may be very small or bigger than a cherry. Ganglions may get bigger as activity increases and more fluid collects in the sac. They may also shrink and may break and go away on their own.
Anyone can get a ganglion: adults between 15 and 40 years old are most likely to be affected.footnote 1 Children don't usually have ganglions, but if they do, the ganglion will very likely go away without any treatment.
What causes them?
Experts don't know the exact cause of ganglions. They may be linked to:
- Inflammation or irritation of the tendon sheath or joint capsule.
- An injury.
- Overuse or repetitive motions, such as those you do at work.
- Arthritis. A common type of ganglion called a mucous cyst ganglion occurs with arthritis of the hands. It usually affects the joint nearest the fingernail.
What are the symptoms?
Ganglions are usually small, painless bumps and do not cause other symptoms.
Sometimes the bump can be tender to the touch, or there can be pain that gets worse with activity or pressure. If the ganglion puts pressure on nearby nerves, you may have tingling in your fingers, hand, or forearm. Some ganglions can weaken your grip or affect joint motion.
How are they diagnosed?
A ganglion can usually be diagnosed based on how it looks and where it is. Your doctor will also feel the bump and shine a light alongside it. If the bump is a ganglion, the light usually shines through it.
You may need an X-ray if your doctor suspects arthritis or injury. Some of the fluid found in the ganglion may be removed and examined. In rare cases, an MRI or ultrasound may be done.
How are ganglions treated?
Ganglions usually don't need treatment, and they often go away on their own. But treatment may be needed if the ganglion causes pain or other symptoms, limits what you can do, affects your bones or ligaments, or gets infected. You may also want treatment if you're bothered by how the bump looks.
Your doctor may treat a ganglion by:
- Giving you a wrist or finger splint to wear.
- Draining fluid from the bump with a needle (aspiration).
- Injecting hydrocortisone into the joint.
- Doing surgery to remove it.
With or without treatment, ganglions may come and go and may get bigger or smaller.
How can you care for yourself?
To care for yourself:
- Use a wrist or finger splint for several weeks. This may be all that is needed for the ganglion to shrink and disappear on its own. Make sure that the splint isn't too tight. Numbness, tingling, pain, or coolness in your hand are signs that you need to loosen the splint.
- Do not smash a ganglion with a book or other heavy object. You may break a bone or otherwise injure your wrist by trying this folk remedy, and the ganglion may return anyway.
- Do not try to drain the fluid by poking the ganglion with a pin or any other sharp object. You could cause an infection.
- If the ganglion breaks open on its own and the skin is broken:
- Cover the wound with a thin layer of petroleum jelly, such as Vaseline, and a nonstick bandage.
- Apply more petroleum jelly and replace the bandage as needed.