A biomechanical study to compare spinal movement in a healthy volunteer during extrication between 'chain cabling' and 'roof off' methods of extrication

Abstract

Introduction: Following a motor vehicle collision some patients will remain trapped. Traditional extrication methods are time consuming and focus on movement minimisation and mitigation. 'Chain cabling' is an alternative method of extrication used in some countries. The optimal extrication strategy and the effect of extrication methods on spinal movement is unknown. This study compares 'chain cabling' to the established roof removal method of extrication on spinal movement.

Methods: Biomechanical data were collected using Inertial Measurement Units on a single healthy volunteer during multiple experiments. The extrication types examined were chain cabling and roof removal. Measurements were recorded at the cervical and lumbar spine, and in the anteroposterior (AP) and lateral (LR) planes. Total movement (travel), maximal movement, mean, standard deviation and confidence intervals are reported.

Results: Eight experiments were performed using each technique. The smallest mean overall movements were recorded during roof-off extrication (cervical spine 0.6 mm for AP and LR, lumbar spine 3.9 mm AP and 0.3 mm LR). The largest overall mean movements were seen with chain cabling extrication (cervical spine AP 5.3 mm. LR 6.1 mm and lumbar spine 6.8 mm AP and 6.3 mm LR).

Conclusion: In this study of a healthy volunteer, roof-off extrication was associated with less movement than chain cabling. The movement associated with chain cabling extrication was similar to that previously collected for other extrication types.

Keywords: Extrication; Motor vehicle collision; Prehospital care; Road traffic collision.