by Dr. Eugene Bailey MD
Clinical Question: Is Protective Equipment Useful in Preventing Concussion?
Bottom Line: There is evidence that helmet use may prevent head injury in skiing, snowboarding and bicycling. The evidence is weak that mouth guards or face shields reduce concussion risk. Evidence may suggest that full facial protection in Ice Hockey may reduce concussion severity when measuring time loss from competition.
Reference: Benson BW, Hamilton GM, Meeuwisse WH, McCrory P and Dvorak J. Is protective equipment useful in preventing a concussion? A systematic review of the literature. Br J Sports Med 2009; 43(Suppl I):i56-i67.
Study Design: Systematic Review
Setting: College and Professional Sports Teams
Synopsis: The use of helmets and other protective equipment (mouthguards and face shields) has been purported to reduce concussion injuries in collision sports. Most of the recommendations are on empirical evidence. This systematic review utilized strict inclusion/exclusion criteria in searching for original research and attempted to assess research quality. Most studies obtained were observational or case-control, and comparison was difficult due to heterogeneity in methodology, the definition of concussion, types of equipment reviewed, different measurement assessments and outcomes and variety of sports.
For mouthguards, most of the studies were observational or case reports. Some of the studies reported benefit in reducing concussion with the use of mouthguards, but others reported no benefit. Sports looked at were football, rugby, and hockey. Two biomechanical studies did show reduction in impact related forces and distortion of the mandibular bones.
One study investigated Helmets and headgear for various sports. For skiing and snowboarding, 3 of 4 studies reported a reduced risk of head injury when wearing helmets, reporting 29%, 60%, and 15% reduction. Two RCTs in Rugby did not show a significant reduction in concussions. In American football, 2 of 3 studies were prospective cohort and one cross-sectional survey. One of the studies showed a reduction in concussion with the new Riddell Revolution helmet. However, the study utilized only a small number of concussion diagnoses and comparison with older helmets. The other two studies didn’t find a significant difference between older and newer helmet designs. In bicycling, the outcomes measured were a head injury, brain injury, and severe brain injury, not a concussion. Helmet use reduced head injury by 63-88%. Lastly, epidemiologic studies in football (soccer), ice hockey and rodeo showed a reduction in head injury but not necessarily concussion. However, several limitations and biases existed for these studies.
Full face shields were added in the 1990s to ice hockey and showed a reduction in dental injuries, facial injuries, and eye injuries. However, in these studies, there was no difference in concussion rates among players wearing different types of facial protection. Moreover, there is clinical evidence that wearing a full facial shield may reduce the severity of concussion (increased time loss) and biomechanical evidence suggesting a reduction in peak accelerations of the head following impact. Many players, still, choose not to wear the full facial protection due to various reasons including fogging, reduced peripheral vision and that they feel like they are a target for the opposition.