The flesh on the edge of the nail is red, swollen and painful, which may be caused by trauma, nail groin infection and so on. 1. Trauma: redness, swelling and pain on the edge of the nail, on the one hand, is due to the usual trimming of the nails, trimming too short or the process of tearing the nails with the hands caused by the manifestation of a wound. Bacteria enter from this wound and cause secondary infection, manifesting as a localized abscess. 2. Nail groove inflammation: It may be caused by the deformation of the nail growth direction, the formation of ingrown nails and other factors, causing nail groove inflammation. The tiny trauma to the tissues around the nail causes bacteria to colonize the skin around the nail, causing redness, swelling and pain at the edge of the nail. There may be other reasons for the redness, swelling and pain of the flesh on the edge of the nail, so it is recommended to consult a doctor in time, follow the doctor’s instructions for further examination, clarify the cause with the help of the doctor, and carry out targeted treatment or therapy.