Citation

Naveen Raj R, Shankar K. Int. J. Numer. Method. Biomed. Eng. 2020; ePub(ePub): ePub.

Affiliation

Mechanical Engineering Department, Indian Institute of Technology Madras, Chennai, India.

Copyright

(Copyright © 2020, John Wiley and Sons)

DOI

10.1002/cnm.3307

PMID

31943820

Abstract

Under-body blast events such as aircraft ejection, mine blast, helicopter crashes pose a serious threat to occupants. These impulsive excitations exert substantial axial loads on the thoracolumbar spine causing severe injuries. The Dynamic Response Index (DRI), which is commonly used as the injury parameter for under body loading scenarios suffers from inherent disadvantages and has been reported to under-predict the chances of injury. The main reasons are, the inability of the DRI model to account for bending loads and posture of the spine. Thus a novel lumped full spine model capable of modelling the spine in different posture along the sagittal plane is formulated. The unavailable data for the model were obtained using inverse parameter identification approach by Eigen frequency matching. Each vertebra has three degrees of freedom: axial, shear and rotary motion to model the flexion of spine. A new injury parameter is proposed based on the sum of compressions caused due to axial and rotary springs at each vertebral level, to account for wedge compression and burst fractures. The results indicate that the the model was able to predict the motions of vertebrae under different postures of spine according to trends in literature. This article is protected by copyright. All rights reserved.

This article is protected by copyright. All rights reserved.

Language: en

Keywords

Aircraft Seat Ejection; DRI; Spinal Injury; UBB