Whether or not an injury to the back of the head will have sequelae depends largely on the size of the area where the force was applied. If the force is light, the patient may have a concussion. For patients with concussion, most of them recover relatively well and do not remain with sequelae. Only a very small number of patients may have post-traumatic brain injury syndrome, that is, its sequelae, which mainly manifests as headache, dizziness, insomnia, anxiety and other symptoms that persist after the injury. If the injury is strong and intracranial hemorrhage occurs, the chances of sequelae are greater in such patients, and the more common sequelae include epilepsy, hemiparesis, limb dysfunction, and cognitive dysfunction. For patients with more severe injuries, the sequelae may also be a vegetative state of survival.