Seizures After Traumatic Brain Injury
In our role as Portland brain injury lawyers, some of our cases involve post-TBI epilepsy, some of which cause visible tonic-clonic ("grand mal") seizures. This article discusses tonic-clonic seizures.
Tonic Clonic or what were historically called Grand Mal seizures are a serious problem that can negatively impact your life. In a traumatic brain injury claim or TBI lawsuit, the onset of tonic-clonic seizures is a very important part of the claim, particularly if the seizures continue for life. In every one of the TBI cases we've handled in the past 25 years involving post-TBI seizures, the defendant or their insurance company will deny that seizures are related to the injury. While the insurance company doctors will tell the insurer (and then testify in trial) that there is not an increased incidence of seizures after a traumatic brain injury, many large population studies from the UK and Denmark have conclusively proven that TBIs cause an increase in seizures and epilepsy. Large scale population studies on millions of test subjects in our document database demonstrate a very clear increase in seizure rates after even one mild traumatic brain injury. Certain factors demonstrate the likelihood of ongoing seizures and permanency of the seizures.
When confronted with that evidence during a deposition or cross examination, the insurance defense doctor will claim to have never seen the study. They will instead testify that you have "psychogenic seizures" that are psychological in nature and then testify that your psychological problems existed before your injury. If you don't have a lawyer who understands the scientific correlation between traumatic brain injury and seizures you would look like you are making up the symptoms and probably lose your case. This false testimony by defense doctors is one of many complex issues that can destroy a brain injury claim if you don't have a highly experienced traumatic brain injury lawyer. With approximately 100 lawyers in the United States handling traumatic brain injuries as 90%+ of their cases, if you have a serious TBI case you don't want a lawyer that merely advertises for brain injury cases; you need a brain injury lawyer who has exensive experience handling TBI cases and winning TBI trials.
Tonic-Clonic Seizures
Tonic–clonic seizures after a brain injury are generalized seizures where abnormal electrical activity in the damaged brain spreads to involve both sides of the brain, causing stiffening, convulsions, and loss of consciousness. They can occur soon after the injury or months to years later as part of post traumatic epilepsy, depending on how the brain heals and whether permanent scar tissue or other structural changes remain. Many medical studies demonstrate that there is a Traumatic Brain Injury causes an increased risk of Post Traumatic Epilepsy. As one example, see Ferguson PL, et al. A population-based study of risk of epilepsy after hospitalization for traumatic brain injury. Epilepsia. 2010;51:891–898. This study shows that the average incidence in all severity of brain injuries is many times the rate in the normal population, including a rate of 4.4% for those who sustain a mild traumatic brain injury, 7.6% in those who sustain a moderate traumatic brain injury and 13.6% in those people who have sustained a severe traumatic brain injury. This is compared to less than 1% in the non-injured population. This same study states that 20% of all patients with seizures have a history of Traumatic Brain Injury.
What do tonic–clonic seizures looks like?
- Sudden loss of awareness or collapse is typical at onset, often without warning.
- Tonic phase (10–20 seconds): body becomes rigid, arms and legs extend or flex, jaw may clamp, breathing can briefly stop, and a cry or groan may be heard as air is forced past the vocal cords.
- Clonic phase (about 1–2 minutes): rhythmic jerking of the limbs, sometimes with tongue biting, drooling or foaming, and possible loss of bladder or bowel control.
- Postictal phase: deep sleep, confusion, headache, muscle soreness, and amnesia for the event, often lasting minutes to hours.
Why do brain injury cause seizures
Brain injuries and the cause of associated cognitive, behavioral, neurological and other conditions is a complex area that remains a leading area of medical research. The following are a few reasons why brain injuries cause an increase in seizures.
- Structural damage: bruises, bleeding, contusions, and later scar tissue can create a “focus” of hyper excitable neurons that fire abnormally.
- Network changes: traumatic injury can disrupt the balance between excitatory glutamate and inhibitory GABA signaling, and alter ion channels (sodium, calcium, potassium), lowering the seizure threshold.
- Spreading activity: once a seizure starts in injured tissue, abnormal firing can propagate through thalamo cortical and brainstem networks so that both hemispheres become involved, producing a generalized tonic–clonic event.
- Timing: “early” post traumatic seizures occur within the first week; “late” seizures, especially beyond one week, are more strongly associated with the development of chronic post traumatic epilepsy.
Risk Factors for Tonic-Clonic Seizures After a Brain Injury
- More severe brain injury (e.g., intracranial hemorrhage, depressed skull fracture, penetrating injuries) increases seizure risk compared with mild concussion.
- Early post traumatic seizures, focal neurologic deficits, and abnormal brain imaging or EEG findings also raise the likelihood of later epilepsy.
- Infections, metabolic disturbances, sleep deprivation, alcohol, and certain medications can further lower the seizure threshold in an already injured brain.
Evaluation and diagnosis of Tonic-Clonic Seizures
- History and eyewitness description: details of loss of consciousness, stiffening, jerking, incontinence, tongue biting, and postictal confusion help differentiate tonic–clonic seizures from fainting or psychogenic events.
- Neurologic exam and imaging (CT or MRI) are not used for the diagnosis of seizures, and can only identify structural lesions such as contusions, hemorrhage, or scarring related to the trauma. But, as we've noted before, traumatic brain injuries are nearly always missed by CT, and are only seen on MRI in approximately 20% of all cases.
- EEG can show generalized spike and wave or focal epileptiform activity, helping determine whether seizures start in a focal injury site and secondarily generalize. But, a negative EEG does not mean that you do not have seizures; the EEG must be on when you are having a seizure to determine whether you have seizures and if so what type.
- Magnetoencephalography or "MEG" is a more advanced type of imaging that is more sensitive than EEG for diagnosing epilepsy and the location in the brain of the seizure activity. While there are few MEG units in the United States, our office has ordered these in our post-TBI seizure cases to help our clients better understand their seizures. MEG has potentially other uses in a TBI case as abnormal frequency rates can demonstrate abnormal function of the brain even without the presence of seizure activity.
Treatment and emergency management
- During a seizure: protect the person from injury, lay them on their side if possible, loosen tight clothing, and do not put anything in the mouth; call emergency services if convulsions last more than 5 minutes, repeat without recovery, or if injury or breathing problems occur.
- Anti seizure medicines: drugs such as valproic acid, carbamazepine, phenytoin, or others are commonly used to prevent recurrent tonic–clonic seizures; monotherapy is usually preferred, with the choice tailored to age, sex, comorbidities, and potential side effects.
- After traumatic brain injury, short term medication may be used to prevent early seizures in high risk patients, and long term therapy is considered if late or recurrent seizures develop (post traumatic epilepsy).
Long term outlook and complications
- Many people achieve good control of tonic–clonic seizures with appropriate medication, though some develop drug resistant epilepsy requiring more advanced treatments (surgery, neuromodulation, or diet therapies).
- Repeated or prolonged tonic–clonic seizures can contribute to cognitive problems, injuries from falls, metabolic complications, and rarely sudden unexpected death in epilepsy (SUDEP), especially when seizures are frequent or uncontrolled.
- Addressing sleep, stress, alcohol, and medication adherence, and following up with a neurologist experienced in brain injury–related epilepsy, are key parts of long term management.
Hiring a Post Traumatic Epilepsy Lawyer
As noted above, hiring the best lawyer for your TBI case is very important due to the complexity of these injuries.
All severities of TBI carry a substantially increased risk of seizures and post traumatic epilepsy. The defense will assuredly deny this. You need an experienced TBI lawyer who has read the medical literature on this issue and knows what the research proves.
If you are seeking a lawyer to handle your brain injury case, please contact us on this web site, or call our office at (503) 227-1233 for a free consultation.