Finger joint lumps and bumps can be disfiguring and a cause of great concern for the patient. Here are some potential causes.

Osteoarthritis, the most common form of arthritis, often affects the hands. When it does, it often causes local inflammation of the distal interphalangeal joints (DIP or last row) and proximal interphalangeal joints (PIP or next to last row). This inflammation causes the joints to swell and hurt. The lumps that form are called Heberdens nodes (DIP) and Bouchards nodes (PIP). Involvement of the base of the thumb may also cause a lumpiness or squared-off appearance.

Gout also causes lumps in the fingers. Gout may cause inflammation of the interphalangeal joints of the fingers. When this occurs, it may be indistinguishable from a flare of osteoarthritis. Middle-aged (post-menopausal) or elderly women on diuretic therapy are particularly prone to developing this. Gout may also cause soft tissue lumps. The diagnosis is made by aspiration of fluid from the affected joint or soft tissue mass with examination of the aspirated material using polarizing microscopy.

Rheumatoid arthritis causes joint swelling involving the wrists, metacarpophalangeal (MCP) joints (knuckles) as well as the PIP joints. Inflammation may lead to lumpiness. Rheumatoid arthritis also causes rheumatoid nodules to develop in the finger joints. These nodules occur in patients with long-standing and severe disease.

Swelling of the tendon sheaths in the palm of the hand may occur with different types of arthritis. This occurs because the tendon sheaths are lined with synovial tissue which may become inflamed. When this happens, the tendon sheath may swell and become lumpy. Sometimes the fingers begin to trigger or catch.

Ganglion cysts can affect the wrist. These are usually painless swellings that have a soft squishy feel to them. The old treatment used to be smashing them with the family Bible. Fortunately, this method of getting religion is rarely used anymore. The ganglion may be aspirated and injected with steroid if painful. Sometimes surgery is required if very symptomatic.

Soft tissue swelling as a result of blisters and calluses are usually not difficult to diagnose.

Plant thorn synovitis is a relatively common problem that may occur in people who grow rose bushes. Here a thorn from a rose bush may break off in the joint and cause a localized inflammation of the finger joint. This condition often requires surgery for both diagnosis as well as treatment.

Infections of the finger joints are a cause of finger lumps and must be treated aggressively. Activities such as fist fights or animal bites may be precipitating factors.

Dupuytren's contracture is a condition presenting as a "lump" or nodule in the palm near the flexion crease, most often at the base of the ring or small finger. This lump or nodule may also occur at the base of the thumb.

A rare disease called histiocytosis may also cause lumps to appear in the distal row of finger joints. Diagnosis is made by biopsy. Treatment is usually symptomatic although in its severe forms histiocytosis may be treated with chemotherapeutic agents.

Painful lumps on the pads of the fingers may develop as a result of bacterial endocarditis. This disease is an infection of the heart valves. The bumps are termed Osler nodes.