Correlation between increase in Neck Strength and decrease in Neck Injuries and Concussion in Athletes and Helicopter pilots

Increase in the number of reported incidences of concussion in football, rugby and other high impact sports have surely created a concern among athletes, family members, coaches and teams due to its severe long-term effects, keeping players off the field and ending careers prematurely. In the United States alone, each year around 300,000 incidences of concussions related to sports are reported among which football players have testified the highest number of such incidences [6]. College level football players who have faced multiple concussions are more prone to suffer concussion injuries in the future compared to players with no such history [7]. Thus, football players with 3-5 concussions are more likely to suffer cognitive impairments, memory loss and depression [8].

There are two main ways that concussion occur. Firstly, when someone experiences a direct impact on their head and secondly, when there is a sudden deceleration or acceleration of the torso, which is transferred to the neck and head directly. These forces can have severe impact and can cause neuronal injury [9, 10]. Concussion could be higher in younger athletes compared to older athletes because of the neurocognitive development. Thus, posing a severe impact on their development with acute and long-term complications [18, 19, 20]. Although the risks associated with high impact sports is immense, however, there is an increase in the number of high school students participating in sports every year. Therefore, there has been an increase in number of young athletes facing the possibility of concussion. This has increased the requirement for better preventive and treatment strategies to decrease the odds of concussion and adverse effects of post-concussion symptoms [21].

It has been found that strengthening of the SCM and UT muscles can possibly decrease the number of concussions as well as the severity [12]. These two muscle groups have been identified to stabilize the head and neck; reducing the head acceleration as well as absorbing the energy generated from direct or indirect impacts [9, 11]. It was reported by NFL laboratory reconstructions that upon increasing the neck stiffness, which increases the neck strength, there is a decrease of 35% of head injury. This was due to significant decrease in peak head velocity, displacement and acceleration [12].

Another segment, which has a very high prevalence of neck pain and injuries, is helicopter pilots. Canadian Forces alone have reported such incidences ranging between 53-85% [13]. The neck pain and injuries are the result of heavy use of night vision goggles [15], helmets, previous complaints of pain in the neck and shoulder [14], vibration of the whole body [16] as well as height of an individual [15].

There has been a lot of research conducted to show that improving neck strength can decrease neck injury incidence in high impact sports [1]. A research conducted by Panjabi et al. [2] has shown that cervical musculature has the ability to generate approximately 80% of force, which is required for the stabilization of the neck. Therefore, any element, which has the potential to compromise the generation of this force, may put an individual to a higher risk of neck injury, neck pain as well as concussion [17]. A research conducted by Collins et.al in high school athletes has shown that neck strength is a major predictor of concussion. It was also found that with an increase in one pound of neck strength there is a decrease in possibility of concussion by 5% [3]. Additionally, research conducted on neuromuscular responses on collisions with lower velocity indicated that our cervical musculature could decrease the deceleration of the neck into the positions of end-range, which can decrease the odds of soft tissue damage of the neck [4, 5].

A study contacted by Tierney et al. [12, 22] has shown that the head acceleration due to collision and sudden change in velocity can be decreased by developing stronger necks, which could possibly decrease sports-related concussion. Therefore, by increasing neck strength even if there could be a minimum decrease in head acceleration, it could significantly decrease the risk of concussion [12].

 

References: 

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