A digital mucous cyst appears alone on the finger, or less commonly, the toe. It is usually near the end of the digit by the nail.
Most are painless, but some can be tender to the touch. They may also cause the nail to become deformed. When the skin on the cyst is broken, the fluid will drain as a clear, jelly-like substance.
Digital mucous cysts usually:
- Appear alone.
- Are clear or flesh-colored.
- Have a shiny appearance.
- Are around 5 to 8 mm large (about the size of a pencil eraser).
- Are found on women who are 60 or older, but anyone can get them.
If the cyst is related you arthritis, your joints may also be stiff and sore, and sometimes deformed.
See your doctor if you develop a cyst of any kind on your hands or feet. Your doctor can check to make sure it is benign and help you decide how to treat it.
See you doctor right away if a cyst suddenly becomes red, hot, and painful as these may be signs of an infection.
Doctors are not sure why digital mucous cysts form. They may be caused by the breakdown of connective tissue due to arthritis. Or they may be caused by high amount of mucin in the skin.
Your doctor will look at the location and appearance of the cyst and ask about your symptoms. A small sample of fluid from the cyst may be sent to a laboratory for testing rule out other health conditions.
Digital mucous cysts often go away on their own. If not, the following treatments may be considered:
- Cryotherapy (freezing)
- CO2 ablative laser treatment
- Draining (sometimes repeatedly)
- Steroid injections
You should not try to drain the cyst on your own. It’s best if a doctor does it in a sterile environment. Otherwise, you run the risk of complications, such as joint infections or permanent damage to your fingers or toes. If the digital mucous cysts are due to fluid coming from a joint, the doctor will try to seal off that spot to keep the cyst from coming back. However, cysts often grow back even when they are removed.
Digital mucous cysts can’t be prevented.
A digital mucous cyst [DIJ-ih-tahl MYOO-kuss SIST] is a common, non-cancerous (benign) cyst. A cyst is a firm, fluid-filled bubble beneath the skin. Digital mucous cysts usually occur near the ends of the fingers (digits) by the nails, but may also be found on the toes.
The cysts are usually small and often painless. When they form by the base of a fingernail or toenail, they can make the nail split, and sometimes cause nail loss. Digital mucous cysts may go away on their own, or you may need a doctor to surgically remove them.
A digital mucous cyst is also known as a myxoid [MIK-soid] (or derived from mucus) cyst, digital ganglion [GANG-glee-ahn] cyst, or digital synovial [si-NOH-vee-uhl] cyst.