CYCLING and CONCUSSION

PART ONE: TEN QUESTIONS

While the data is a little old, it does underscore the degree of risk involved in cycling as it relates to sports-related injuries. In 2009, the American Association of Neurological Surgeons reported that of the 447,000 sports-related head injuries that were evaluated in U.S. emergency departments, 86,000 of them were related to cycling accidents. That made cycling the biggest cause of sports-related head injuries with football being a distant second with 47,000 head injuries reported. A common result of these head injuries is what has been historically referred to as a “concussion”. Let’s look closely at what this term and it’s implications means.

1) What is a concussion?

There are many definitions. There are formal detailed medical definitions and there are functional definitions. I prefer the latter of the two. I like the following, “a concussion is an injury to the brain that results in temporary loss of normal brain function and is usually caused by a blow to the head”.  Many people assume that concussions involve a loss of consciousness. That is a misconception. Often, a person with a concussion never loses consciousness. Another misconception is that that one can have a “minor” concussion. There are no “minor concussions” , as we will discuss in question #9.

2) How do they occur?

The brain is cushioned inside the skull by cerebrospinal fluid. In the setting of an abrupt, violent blow to the head, or even rapid deceleration, the brain can collide with the inner surface of the skull. This puts the brain at risk for tearing of blood vessels, pulling or shearing of nerve fibers and bruising of brain tissue.

3)Who gets them?

The contact sports of football, ice hockey, boxing, rugby, and soccer are often cited in the press as having a high incidence of concussion. The study referred to earlier obviously implicates cycling as an at-risk activity. When you consider the mechanism of injury outlined in question 2, we are all at risk pretty much all the time. Motor vehicle accidents, falls, assaults, and occupational accidents are other other events that can result in concussion. 

4)What are the symptoms of concussion?

Confusion is a primary symptom. It’s principal features include an inability to maintain an organized stream of thought, lack of awareness, easy distractibility, and an inability to carry out goal-directed movements. Confusion, however, is only one of the symptoms in a long laundry list of uncomfortable disorders. Prolonged headache, visual disturbances, dizziness, nausea or vomiting, impaired balance, memory loss, ringing in the ears, and light sensitivity can all occur. 

5)How can you recognize that someone may have a concussion?

Signs observed in someone with a concussion may include a vacant stare, slow response to questions or instructions, easy distractability, disorientation, slurred or incoherent speech, incoordination, memory deficits, and a period of loss of consciousness. Seizures are uncommon for this degree of brain injury and, if present, would suggest a more severe condition.

6)What should be done

If the symptoms and signs outlined in questions 4 and 5 occur after a blow to the head, a health-care professional should be consulted as soon as possible. A loss of consciousness or change in mental status requires a 911 call.

7)How is a concussion diagnosed?

The acute evaluation of an individual with possible concussion includes neurologic assessment and mental status testing. Prolonged loss of consciousness, persistent mental status changes, or abnormalities on neurologic examination require neuroimaging, specifically, a cat scan of the brain. It is possible to have a normal CT scan and still have a concussion.

8) How is concussion treated?

For those with an uncomplicated concussion a period of physical and cognitive rest is often recommended for at least 24 hours and sometimes longer depending on the symptoms present. This means avoiding general physical exertion and limiting activities that require thinking and mental concentration. Headaches should be treated with Tylenol. Pain relievers like Advil and aspirin should be avoided as they may increase the risk of bleeding.

9) What are some of the residual problems associated with concussion?

Postconcussion syndrome may include headache, dizziness, disrupted thought processes, and mental disorders resulting from disease of the nervous system. “Postconcussion Syndrome” will be the topic of Part 2 of “Cycling and Concussion”.

Post-traumatic vertigo includes dizziness that may be accompanied by hearing symptoms and balance problems and contributes significantly to disability after concussion. 

A very rare complication exists that is generally fatal. This occurs when there is diffuse swelling of the brain following a second concussion while someone is still symptomatic from an earlier concussion. Again, this is very rare.

There is evidence that individuals who have had one head injury are at increased risk of recurrent head injury with some studies showing a six-fold increase in risk. 

10)Can concussions be prevented?

Bicycle helmets can reduce the severity of accident-related head injury but concussion can still occur. Being visible to drivers, being predictable with your behavior on the road and communicating well with your fellow cyclists will all contribute to avoiding an injury in the first place.