The workers' compensation systems is there for those that really need it. Those who abuse it make it much harder on those who are really injured because they make everybody's claim look a little more suspicious.
Workers' comp insurance fraud costs insurers more than $7 billion each year -- so they have good economic reasons for being suspicious of some claims. Unfortunately, it's easy for legitimately injured workers to get caught up in an investigation where you're presumed to be faking until proven injured.
Ultimately, workers who suffer from head injuries that affect their ability to think clearly react in a timely manner, keep their emotions in check and communicate efficiently are often at a disadvantage if there's no medical way to prove that their conditions are real. However, a perfectly normal-looking brain may still function abnormally for any number of reasons. This can open the injured worker up to allegations that he or she is feigning an illness to get out of work.
Usually, workers' compensation is meant to be the "exclusive option" available to injured workers. Essentially, in order to have coverage under workers' compensation -- which will cover your injuries even if you are at fault for the accident that caused them --- you legally give up you ability to sue your employer for negligence instead.
The best way to reduce the possibility of a severe injury on the job is to be conscious of the risk -- and then take carefully considered measures to reduce that risk.