Salah is wajib (obligatory) in any circumstance but the laws ease when in difficulty.
If the wound is permanent then one has to perform salah in whatever way is comfortable with the patient.
If there is no bleeding then it's not a problem at all and if it is in the places of wudhoo, then wudhoo e jabeerah is done.
In cases where the wound is bleeding, the wound can be covered during salah so as to avoid blood (najasah) to flow since it's a hadath and in
salah, taharah (religious purity) is a necessity.