Ganglion Cyst

What it is

Ganglion cysts are common lumps of the hand and wrist. Think of a water balloon on a stalk: the stalk connects to a joint or tendon sheath, and the balloon fills with clear, jelly-like fluid. Cysts are most often on the back of the wrist, on the palm side of the wrist near the thumb, at the base of a finger, or near the fingertip joint (a mucous cyst). They are not cancerous and do not spread.

What causes it

The cause is unknown, but cysts may form with joint or tendon irritation, arthritis, or injury. They occur at all ages.

Symptoms

• A round or oval lump that may grow, shrink, or disappear
• Aching or tenderness, especially with gripping, though many are painless
• With mucous cysts, a groove in the fingernail

If the skin over a fingertip mucous cyst breaks and becomes red or painful, call promptly: the opening connects to the joint, and infection needs urgent treatment.

Diagnosis

The diagnosis is usually based on the lump's location and appearance. X-rays can check the nearby joints, and ultrasound or MRI can help when a cyst is suspected but hard to feel.

Treatment

Observation: painless cysts can simply be watched, and many go away on their own.

Splints and anti-inflammatory medication: can ease activity-related pain.

Aspiration: draining the cyst with a needle in the office. Recurrence is common because the stalk remains.

Surgery: removing the cyst with its stalk, through an open or arthroscopic approach, for cysts that are painful, limiting, or keep returning.

Recovery

Surgery is generally successful, though a cyst can still come back. A painless recurrence can be left alone; a painful one can be removed again.