If it's not too deep, a bath is okay. Patients with bedsores and leg ulcers are put in tubs and whirlpools all the time. You can gently lather the area. Lastly rinse real well. Then pat dry and slather some antibiotic ointment over the area and cover with gauze. Another treatment is to cover with squares of gauze moistened in saline (salt water) and cover all that with dry material. Letting a hard crust form is no longer considered the best thing.