One of the main requirements of a migraine diagnosis is that all other causes of the migraine symptoms have been ruled out. Therefore migraines are diagnosed only after the doctor has determined the symptoms aren’t caused by an underlying seizure disorder, vision problem, sinus problem or other illness. However, migraine and previous head and neck injury appear linked in some cases. When the head trauma is the main cause of the migraines, it is called posttraumatic migraine.
There are no concrete numbers on how many people who have migraines suffered an earlier head or neck injury or how many people who have a previous head or neck injury will eventually have migraine attacks. However, several studies have shown a relationship between these injuries and migraines and many migraine sufferers say they have migraines due to concussions. A Norwegian study of 105 people with head or neck injuries examined the people 22 years after their injury. The study found 82 percent of the women and 70 percent of the men complained of head pain.
Head pain is actually the most common symptom after a head injury—about half of people who have experienced a concussion complain of head pain for more than two months. This is known as post-concussion syndrome. Even after a mild head injury the pain can continue to occur for years. About a quarter of post-concussion head pains have migraine symptoms similar to the symptoms of migraine without aura. Symptoms include: throbbing pain, pain on one side of the head and nausea.
Before diagnosing migraine, the migraine doctor must first ensure that no other internal problem is causing the symptoms. Doctors must rule out fractures, bleeding in the brain, seizure and transient ischemic attack — which is also called a TIA or mini-stroke.
Hemiplegic migraine, which causes temporary paralysis, may be triggered by a mild head trauma such as a bump on the head.