Cameron Marshall recently completed a review of sports concussion. The author begins with a review of the current state of affairs; that 90% of concussions do not result in a loss of consciousness, that they account of 8.2% of all high school sports injuries, that 50% of concussions are from football players, that 12.6% of those with concussion also had moderate to severe neck pain. He also points out that while increased neck strength should prevent concussions and decrease their severity- it has no impact in football because the bulk of players who are concussed are hit from an oblique angle and are unaware of the impending impact- thus they do not stiffen their necks until after impact has been made.
The author continues with a brief discussion of the sub-concussive forces found in women’s soccer while heading the ball and demonstrates that at this time, no evidence exists to indicate that a single season will cause long-term neurological damage (keep in mind the study we cited).
Recalling that a concussion is a functional change in neurology rather than a structural change, symptoms and diagnostic criteria are discussed. The physiological consequences of impacts to the brain are detailed and the different scales for measuring a concussion (few with enough evidence to fully endorse or support, despite their being free or pay for use) are then explored. It is unfortunate that even at this late date we have so few worthwhile tools that can help coaches identify the difference between who needs to sit on the sidelines for a few minutes and someone who should go to the ER. Even doctors have poor protocols in trying to determine who should have a head CT and who should simply be observed. This area of medicine is rapidly evolving.
The conclusion reviews that at this time, best evidence indicates that a concussion is a result of a blunt force trauma to the head or body which deforms neurological tissue causing ATP deficiency. This can cause a variety of symptoms. Most of these will spontaneously clear up within 7-10 days.
Initial examination should focus on ruling out skull fracture and cervical spine injury. The SCAT2 (discussed here), cranial nerve and cerebellar exams should follow. Severe or worsening headache, seizures, multiple episodes of vomiting, unsteady gait, poor speech, pins and needles or numbness in the extremities or Glasgow Coma Score below 15 indicate that a visit to the ER is worthwhile.
A coach or parent should be present to give information about changing signs and learn about the proper return to play protocols.
This is a current and up to date assessment of where we are in terms of concussion research. Realize that neuroscience is evolving quickly but that at this time, we still only have a crude understanding of these mechanisms and how they work. As we learn more, protocols with better evidence for determining who needs to see a doctor, who needs a CT scan (which may or may not show deformation) and what return to play protocol to follow will be standardized in better science rather than based on observation.