When someone has a brain concussion, will it cause a blood clot in the head?

Not causative: Concussion is an alteration in consciousness associated with brain injury. Deep brain centers for consciousness are often damaged by rapid rotation or acceleration-deceleration of the brain. In these cases blood clots may also occur. The blood clots can be a surgical emergency even when concussion does not occur.

Not Necessarily: Concussions are injuries to the brain by trauma. If the blow is severe enough, bleeding may occur. The cause is the trauma, concussions and bleeding can be the results.