Recently I have seen a few patients in my office with minor concussions. They all pressented with post concussive symptoms and hence that shall be the focus of my post on this gorgeous June day. So what is a concussion and what is a “minor” concussion? Concussion is usually a closed head injury with temporary loss of brain function or rather loss of consciousness. By closed head injury, I mean that nothing penetrated the brain. Example of a penetrating head injury shall be a gun shot wound to the head. Do not get me wrong here-obviously a penetrating head injury shall likely result in loss of consciousness and temporary or permanent loss of some brain function.
That said the word concussion is more commonly used for closed head injuries. Let me give you a few prime examples of concussion. I am a big fan of boxing and the UFC. Anyone who watches these sports has seen a concussion. Boxer A walks into a stiff jab thrown by Boxer B. Down he goes and is out for the count. The ringside doctor jumps into the ring to examine him. Flips his eyes open and flashes a light into both of them. After a momentary loss of consciousness, our fallen boxer comes to. Open his eyes but has a dazed look. He is able to answer the ringside doctors questions (show me two fingers with your left hand). He struggles to his feet but his legs are wobbly. The referee consults the doctor and decides to halt the fight. So what happened to our boxer? He just sustained a concussion.
Concussions can be graded into mild, moderate and severe. This is quite arbitrary. If the loss of consciousness is more than half an hour the concussion is graded as severe. Minor concussions, which shall be the focus of our talk henceforth, are usually associated with either no or momentary loss of consciousness. Let me give you a few examples of minor concussions. Walking into a door, bumping your head against a low lying ceiling or a car door are all examples of minor closed head injury with or without concussion. Majority of patients walk away from such an injury and never seek any medical attention because they experience no ill-effects. A few though are not so lucky and post the head injury are plagued by headache (post concussive headache), problems with memory and concentration (especially when they are multi-tasking) and a myriad of other complaints such as subjectively feeling off balance, difficulty with sleeping and mood changes such as irritability. All these symptoms after a closed head injury/ concussion are included under the umbrella of post concussive symptoms.
In my next post, I shall discuss post concussive syndrome and its treatment.
Nitin Sethi, MD
In this post I thought I would talk a little about what is called post concussive syndrome (PCS). Before we discuss PCS, we need to understand just exactly what is a concussion. Unfortunately though there has been realms of data generated on this, the word concussion still remains quite ill-defined in the medical literature. Basically it refers to a brief loss of consciousness. Lets use an example. You are in the ring against Iron Mike. You have your right and left going but walk into one of Iron Mike’s jabs. Boom your legs give away under you and you are on the mat unconscious seeing “stars”. You are “out” for a few seconds and then boom you come out and are looking up at the referee to ask “where am I? what happened to me?”
Concussion may then also be referred to as a minor head trauma or rather a minor closed head trauma accompanied by brief loss of consciousness. Closed since there is no breach in the skull. The head injury occurs but nothing penetrates the skull. Concussions are thus common and they may occur during a MVA, sports related concussions are common (injuries during football, ice-hockey, boxing and other contact sports where blows to the head may occur). The exact mechanism why there is that bried period of unconsciousness which then resolves and the person wakes up is not fully elucidated. The thinking is that during the concussion, the brain is subjected to mechanical and kinetic forces which “shake” the brain inside the rigid cranium. The brain though is free to move inside the skull, it is attached by the brainstem which is relatively immobile. So as the brain turns on its axis, there is transient dysfunction of the brainstem and this leads to loss of consciousness and the person blacks out.
Concussions are usually not life threatening and the patient comes around in a few seconds to a few minutes. Those associated with a prolonged period of unconsciousness though need to be evaluated in the hospital to make sure there is nothing serious or structural such as an intracranial hemorrhage (bleed) into the brain or outside the brain but inside the skull (epidural hematoma). There are guidelines with respect to sports related concussion injuries and usually the doctor at the side of the play field makes a decision whether it is safe for the player to play again during that game or should he sit out the rest of the game. Multiple concussive injuries increase the risk of sudden death (no one quite knows by what exact mechanism) and hence concussive injuries in professional players like those who play football do deserve special attention.
Let us now turn to what is called PCS. Again there has a lot which has been written about PCS but this syndrome is ill-defined and its etiology is far from clear. Patients who have suffered a concussion frequently complain of memory problems following the concussion. Apart from memory difficulties these patients may complain of mood changes been too irritable or short tempered, balance problems and unsteady gait, dizziness, headaches, fatigue and lack of energy. This constellation of signs and symptoms with a preceeding history of concussion is what has been referred to as PCS. When these patients present to neurologists, we investigate them but most of the time all the tests come back as “normal”. Their imaging studies like CT scan head and MRI brain are normal.
PCS is usually treated symptomatically. If headache is the major complain we treat the headache. If dizziness is the major complaint we treat with an antivertigo drug. At times low dose antidepressants may be helpful. The natural history of this condition is good and most patients recover in due course and are able to go back to their day to day life.
Nitin Sethi, MD