Nails are squeezed and turned black because the capillaries under the deck are broken and bleeding, and the blood does not come out. Black nails will appear over time. Let's rule out bone damage first. You can take pictures in the hospital.

There is no bleeding from the wound, no redness, swelling, heat and pain, and no need to deal with it. After a long time, new nails will replace the old ones. If there is bleeding, the wound must be debrided. It can be disinfected with iodophor or alcohol, then wrapped in gauze and combined with some oral anti-inflammatory drugs.

As one of the accessories of the skin, nails have their specific functions. First of all, it has the function of "shield", which can protect the pulp of the distal phalanx from damage, maintain its stability, enhance the sensitivity of finger touch, and assist hands to grasp, hold, pinch and squeeze. The nail bed is rich in blood supply and has the function of regulating peripheral blood supply and body temperature. Secondly, nails are the focus of hand beauty, and beautiful nails add charm to women.