Do people always need skin grafting after fasciotomy surgery?

Not always: There are a variety of methods to avoid or minimize the use of skin grafts for fasciotomy wounds which include specialized tissue expanders or vacuum assisted closure.

Not always: Fasciotomy is a procedure to decompress vital tissue that has swollen for some reason and is contained by fascia, the tough unyielding membrane that surrounds muscle. If not decompressed, the muscle (and nerve and tendon and vessels, etc) will die. Sometimes, when the swelling resolves, the fasciotomy wound will close by itself, leaving a linear scar. Other times, skin grafting will be needed.