Although acoustic emission (AE) signals from isolated spinal ligament failures have lower amplitudes and frequencies than those from vertebral body fractures, it is not known if AE signals could be used to differentiate between injured structures in spine segment testing. The objectives of this study were to evaluate differences in AE signal amplitudes and frequencies resulting from injuries of various tissue types, tested as part of a spine segment, during dynamic loading. Three‐vertebra specimens from the human cadaver cervical spine were tested in dynamic eccentric axial compression with lateral eccentricities. Specimens were tested with low (n=6) and high (n=5) initial eccentricities of 5 and 150% of the lateral diameter of the vertebral body, respectively. AE signals were recorded using two sensors. The time of injury initiation was identified for seven vertebral body and/or endplate fractures and five intertransverse and/or facet capsule ruptures. Hard tissue injuries resulted in higher peak amplitude AE signals than soft tissue injuries. Characteristic frequencies of AE signals from the sensor on the concave side of the lateral bend from failures of hard tissues were greater than those from failure of soft tissues. These findings suggest that AE signals can assist in delineating injured structures of the spine.
Keywords: acoustic emission, experimental, ligament, spine, vertebra