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Published on: September 21, 2017
Initial Head-Neck Posture Affects Neck Injury Risk in Pilot Emergency Ejection
Introduction:
Neck injuries are commonly sustained during emergency aircraft ejections, with head-neck posture identified as a critical factor influencing injury risk. Despite this, the relationship between the initial head-neck posture and neck injury during emergency ejection has not been comprehensively studied. The objective of the present study was to investigate the effects of head-neck postures on the dynamic neck response of pilots during ejection.
Methods:
Using the Total Human Model for Safety, simulations were conducted involving four initial postures (i.e., rotation, flexion, extension, and lateral bending), each set at 15°, and four initial rotation angles (0°, 15°, 30°, 45°). Ejection acceleration curves were also simulated to the T1 vertebra and its inferior segments.
Results:
Neutral posture poses no risk of injury. In all the non-neutral postures (15°), only the rotation of 15° may cause risk of neck injury, and notably, this risk increases as the rotational angle increases.
Discussion:
Initial head-neck posture markedly influences cervical loading and injury risk during ejection. Axial rotation presents the greatest risk by elevating vertebral stress and ligament tension, emphasizing the critical importance of maintaining a neutral posture to protect the cervical spine during pilot ejection. Du C-F, Zhang X-Y, Zhao H, Liu S-Y, Li T-C, Wang X-W, Zhou K-T. Initial head-neck posture affects neck injury risk in pilot emergency ejection. Aerosp Med Hum Perform. 2026; 97(3):145-150.
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