Hard and black fingers may be caused by scleroderma, gangrene and other reasons.
1. Scleroderma: hard black fingers may be caused by scleroderma, scleroderma is a diffuse, or limited skin hardening and thickening of the main features of connective tissue disease, symmetrical sclerosis of the skin at the extremities of the scleroderma is the main clinical manifestations of scleroderma, but also often manifests itself in the cold or nervousness, the sudden emergence of the hands and feet cold and so on.
2. Gangrene: hard and black fingertips may also be caused by gangrene, which is a special form of change such as black color after ischemia or infection leading to tissue necrosis due to secondary putrefactive bacterial infection and other factors. Common symptoms include change in skin color, numbness, pain and swelling.
Finger tip hardness and blackness is recommended to go to the hospital in time, under the guidance of the doctor for active treatment.