Digital Mucous Cysts

Digital mucous cysts are small membranes that generally develop near the fingernails, expanding as they fill up with fluids. These cysts are typically benign and often form around the top knuckle near the fingernail, referred to medically as the distal interphalangeal (DIP) joint. Even though these cysts normally arise around fingernails, they can also develop around toe nails also.

Causes of Digital Mucous Cysts

There are traditionally two major types of digital mucous cysts. Each type can develop in a patient for vastly different reasons.

One type of digital mucous cyst occurs when fluid leaks from a nearby joint in the finger. The underlying cause can trace back to external trauma, arthritis, or another cause. But when joint-lining fluid in the fingers or toes leaks somewhere else, it can develop into a digital mucous cyst. 

Another type of digital mucous cyst relates to a substance known as mucin, which is a protein with a consistency similar to gelatin. If there is a build-up of mucin in the DIP joint, it can contribute to the development of a digital mucous cyst.

Symptoms of Digital Mucous Cysts

The symptoms of digital mucous cysts are usually relatively minor. Many of these cysts are painless, even if they are unsightly. In more severe cases, digital mucous cysts can produce painful symptoms in the affected joint. 

If the cyst becomes irritated, it can rupture and some of the fluid will drain out. This is not normally a huge problem. But as digital mucous cysts are connected to a joint, infection is a severe concern. If a cyst becomes infected, it can spread to the underlying joint and make the patient’s symptoms exponentially worse.

Treatment of Digital Mucous Cysts

Before assessing potential treatment methods, a qualified doctor should complete a thorough examination of the patient. In addition to a physical examination, a doctor will usually take an X-ray and may perform a biopsy to properly identify digital mucous cysts. 

As digital mucous cysts can arise for different reasons, patients should not attempt to treat this condition on their own. Without the assistance of a qualified doctor, patients may experience additional complications, such as an infection or permanent damage to the joint in question. 

In order to treat digital mucous cysts, a doctor might recommend any or all of the following treatment options:

• Drainage —Draining fluid build-up in a sterile environment is one effective method to treat digital mucous cysts;
• Excision — Conducting surgery to excise or remove the cyst is a common treatment option that is often effective; or
• Cryotherapy — Freezing or applying cold is an effective way to treat digital mucous cysts.

Contact a Doctor for Help with Digital Mucous Cysts

If you have any of the signs or symptoms of digital mucous cysts, it can be extremely constructive to contact a knowledgeable orthopaedic doctor. At the Orthopaedic Associates of Riverside, our roster of board-certified doctors have a dedicated focus on orthopaedic medical issues, including digital mucous cysts. If you have digital mucous cysts or another condition, contact us to evaluate your options.