It’s important to understand that individuals who lost hair in an accident may or may not fully regrow the hair that was lost. If the injury does not go deep (and is more of a scrape than a tear in the skin) the chances of good healing and hair growth is high. If the injury is deep, the chances of regrowth is lower. The first and most important step is to help the area heal by optimizing all the wound healing steps over the first 6 months. This involves keeping the area clean, and fighting off any infection. Sutures may be needed if any area is open. Antibiotics may be needed in some cases. Tetanus vaccination may be needed as well depending on the type of injury. The is of hair growth rememedies in the early stages have minimal role. Over time, one needs to also consider inflammation that might be present in the area as excessive inflammation can impair growth. Hair growth treatments (minoxdil) may have a role to support hair cycling in a healing wound. Please see a physician to guide you in these areas.