Human and behavioral factors contibuting to spine-based neurological cockpit injuries in pilots of high-performance aircraft: Recommendations for management and prevention

Military Medicine, Jan 2000 by Jones, Jeffrey A

Pain reporting for pilots who stretch or exercise before flight was subsequent to initiation of these activities, because many pilots had experienced in-flight pain before beginning a stretch or exercise regimen. Eighty-three percent of F-16 and 44% of F/A- 18 pilots reported stretching their necks before flying. Unfortunately, 76% of pilots who stretch still have experienced subsequent pain episodes during or after flight. There was no statistical difference between pilots who stretch and those who do not stretch in the number of pain episodes in either aircraft (mean = 0.24; p = 0.624).

Fifty percent of F-16 and 28% of F/A-18 pilots now consistently participate in weight training exercises for the neck muscles. The number of pain episodes in pilots who exercise regularly in both the F- 16 and F/A- 18 have been reduced compared with those in pilots who do not exercise; however, the difference was not significant in F- 16 pilots, but it approached significance in the F/A-18 group (mean = 2.492; p

Discussion

There are several problems in performing an epidemiologic survey of this type in this population. Extracting information, i.e., survey participation, can be quite challenging, because pilots in general are reluctant to provide accurate personal, medical-type information. They also rarely demonstrate the patience to voluntarily complete a detailed survey en toto. Only one F- 14 pilot responded; therefore, those data were not included in the analysis. Also, there will be bias in completing a self-report survey, both observational and recall bias, which often leads to misclassification. There are obvious confounding variables that cannot be clearly sorted in a limited brief survey. With an unproven survey data form, both the reliability and the validity of the data can be questioned. Finally, a larger sample size for all aircraft types would allow a true cross-sectional survey and would reduce variability of the data within groups. Obviously, a prospective cohort study will be beneficial to accurately compare injury events by type of aircraft and to establish a valid mechanism of injury.

We feel that the cases reported here document a unique medical scenario that results from the highly unusual environmental stressors experienced by these pilots. In both cases presented, there was injury to the cervical nerve roots without clear-cut associated herniated nucleus pulposus (HNP) on magnetic resonance imaging. Twisting the neck to full rotation and loading up to 150 pounds of weight onto the cervical spine is unique to the fighter pilot community. Acute neck pain, often with referral into the shoulder or arm and often associated with right upper extremity paresthesias (radiculopathy), is the result of this occupational exposure. We believe that the nerve root is injured by the bony lamina under the compressive force but that the force is not great enough to produce frank disk herniation. This is why these injuries are acute or subacute and can resolve with more conservative therapies. The injury mechanism is different from that reported previously in no-ejection-related spinal injuries., 13