This will depend upon the type of injury sustained. Some injuries are apparent immediately following the accident, while other injuries will take hours, days, or even weeks to become obvious. While some patients may not be able to tell that they've been injured as a result of their car accident, a chiropractor can diagnose many conditions quickly. This is why seeing a chiropractor following an accident is so important: because your chiropractor may be able to diagnose your condition and get you started on treatment before you've even realized that you've been injured.