What is the difference between Post Concussive Syndrome (PCS) and traumatic brain injury?  Post Concussion Syndrome or postconcussive syndrome typically results from a concussion due to a head injury.  My office handles cases typically resulting from head injuries sustained in automobile accidents, trucking accidents or motorcycle accidents.  These injuries may involve Post Concussive Syndrome and/or related traumatic brain injuries. Often, a traumatic brain injury may also have post concussion features.  It is often thought that a traumatic brain injury must necessarily involve a loss of consciousness, but this is not necessarily the case.  Similarily, a loss of consciousness is not necessarily predictive of continued post concussion syndrome.  Are mild head injuries as mild as we think? Neurobehavioral concomitants of chronic post-concussion syndrome, Annette Sterr, Katherine A Herron, Chantal Hayward, and Daniela Montaldi, BMC Neurol. 2006; 6: 7.

Not every head injury will result in a traumatic brain injury, or even post concussive syndrome, which is a more minor subset of traumatic brain injury. However, if a concussion is suspected, medical review by a neurologist (specializing in traumatic brain injury) should occur. Sometimes, a concussion may not present any lingering symptoms and usually resolves after several weeks or months.  However, a mild traumatic brain injury (mTBI) can often result in post concussive syndrome, which has concussion features lasting for an extended period of time, typically more than 120 days.  These features may include frequent headaches (typically not resolved with the use of normal analgesics), fatigue, poor memory and concentration, sleep disturbance, and dizziness.  There has been a correlation shown between traumatic brain injury and loss of blood flow to affected areas.  These sequelae are typically present in mTBI cases with post concussive syndrome features.  See, e.g., Temporal Profile of Cerebrovascular Reactivity Impairment, Gray Matter Volumes, and Persistent Symptoms after Mild Traumatic Head Injury, da Costa L, van Niftrik CB, Crane D, Fierstra J, Bethune A,  Front Neurology, May 11, 2016, 7:70.

Typically, it is thought that a concussion necessarily results in a loss of consciousness, or disorientation following the accident, and that symptom is sometimes explored in initial ER diagnosis.  Thus, the correlation goes, without a loss of consciousness, there cannot be a traumatic brain injury or post concussive syndrome (as a subset of mTBI).  However, studies have demonstrated that a loss of consciousness is not necessarily predictive of continued post concussion syndrome.  Are Mild Head Injuries as Mild as We Think? Neurobehavioral Concomitants of Chronic Post-Concussion Syndrome, Annette Sterr, Katherine A Herron, Chantal Hayward, and Daniela Montaldi, BMC Neurol. 2006; 6: 7.

Further, mild traumatic brain injury may lead to persistent post-concussive syndrome which affects cognitive performance in more than one-half of those suffering from PCS. These features may predict early onset Alzheimer’s in a significant portion of patients affected with mild traumatic brain injury with post concussive features. Further, adolescent females may exhibit a greater level of symptoms of post concussive syndrome than males.  Post-Concussion Symptoms in Mild Traumatic Brain Injury: Findings From a Paediatric Outpatient Clinic, Dillard C, Ditchman N, Nersessova K, Foster N, Wehman P, West M, Riedlinger B, Monasterio E, Shaw B, Neblett J., Disabil Rehabil. March 13, 2016:1-7.