An investigation into axial impacts of the cervical spine using digital image correlation

作者:Holsgrove Timothy Patrick*; Cazzola Dario; Preatoni Ezio; Trewartha Grant; Miles Anthony W; Gill Harinderjit Singh; Gheduzzi Sabina
来源:Spine Journal, 2015, 15(8): 1856-1863.
DOI:10.1016/j.spinee.2015.04.005

摘要

BACKGROUND CONTEXT: High-energy impacts are commonly encountered during sports such as rugby union. Although catastrophic injuries resulting from such impacts are rare, the consequences can be devastating for all those involved. A greater level of understanding of cervical spine injury mechanisms is required, with the ultimate aim of minimizing such injuries. PURPOSE: The present study aimed to provide a greater understanding of cervical spine injury mechanisms, by subjecting porcine spinal specimens to impact conditions based on those measured in vivo. The impacts were investigated using high-speed digital image correlation (DIC), a method not previously adopted for spinal impact research. STUDY DESIGN: This was an in vitro biomechanical study. METHODS: Eight porcine specimens were impacted using a custom-made rig. The cranial and caudal axial loads were measured at 1 MHz. Video data were captured with two cameras at 4 kHz, providing measurements of the three-dimensional deformation and surface strain field of the specimens using DIC. RESULTS: The injuries induced on the specimens were similar to those observed clinically. The mean +/- standard deviation peak caudal load was 6.0 +/- 2.1 kN, which occurred 5.6 +/- 1.1 ms after impact. Damage observable with the video data occurred in six specimens, 5.4 +/- 1.1 ms after impact, and the peak surface strain at fracture initiation was 4.6 +/- 0.5%. CONCLUSIONS: This study has provided an unprecedented insight into the injury mechanisms of the cervical spine during impact loading. The posture represents a key factor in injury initiation, with lordosis of the spine increasing the likelihood of injury.

  • 出版日期2015-8-1