What should you know about a swollen black hand?

Blood under the skin after a knock, crush injury, or fracture can look dark as it spreads through tissue. A distal radius fracture may cause wrist and hand swelling with bruising, tenderness, or difficulty moving the wrist. Tight rings, dressings, or splints can worsen pressure as swelling increases. Less commonly, a circulation problem can make the hand blue, purple, or black, especially when it is colder than the other hand. Joint inflammation such as rheumatoid arthritis can swell the hand, but sudden dark color is not something to diagnose at home.

Remove rings and other constricting items now. Keep the hand supported and elevated if that feels comfortable. Do not apply tight tape, heat, or ice directly to dark skin, and do not try to drain a blister. Compare color, temperature, sensation, and finger movement with the other hand. If a splint or bandage feels tight, seek urgent advice rather than altering it yourself. A clinician may check blood flow and nerves and arrange imaging when a distal radius fracture is possible.

Call emergency services for a hand that is cold, rapidly darkening, severely painful, numb, weak, or difficult to move. Emergency help is also needed if swelling followed a major crush injury or if the person feels faint or unwell. Prompt review is required for spreading redness, fever, an open wound, or worsening swelling. Even when bruising seems likely, arrange assessment if the color does not improve or the hand cannot be used normally.

Is the dark color consistent with bruising, or is blood flow reduced? Could there be a fracture or pressure from a splint? Do I need imaging? Which changes in color or sensation should send me back urgently?