What should you know about cysts on fingers under skin?

A cyst on a finger can sit near a joint, tendon, nail, or the skin itself. It may feel smooth and firm, fluctuate in size, or become noticeable when the finger bends. A lump near a joint can affect movement or feel uncomfortable with gripping, while a lesion near the nail can alter the nail surface.

Not every finger lump is a skin cyst. Injury, inflammation, infection, and changes around a joint can look similar from the outside. A clinician considers the exact position, whether the lump moves with the skin or joint, how long it has been present, and whether sensation or strength has changed.

Avoid hitting, squeezing, or attempting to burst the lump. Remove rings if swelling makes them tight, and keep a simple record of changes in size, pain, colour, and movement. Reduce activities that repeatedly press on the area until it has been assessed if gripping is painful.

Treatment depends on the diagnosis and location. Observation may suit a small, quiet lump. An intralesional steroid injection can be discussed for selected inflammatory lesions, whereas drainage is used when a clinician identifies a collection that needs releasing. Cyst removal may be considered when the lump recurs, restricts function, or remains troublesome.

Arrange review for a growing lump, persistent pain, reduced bending or straightening, numbness, weakness, or a change around the nail. Seek prompt help if the finger becomes rapidly red, hot, very swollen, severely painful, or starts draining, particularly with fever or a recent wound.

Is the lump connected to the skin, joint, tendon, or nail? Do I need imaging or simply observation? Which treatment would protect movement, and what recovery or wound care would follow a procedure?