Sound and vibration recordings during normal motion and spinal manipulation

Abstract

Novel methods assessed and localized zygapophyseal (Z) joint audible sounds (crepitus and cavitations) during normal lumbar motion and side‐posture spinal manipulation (SMT).MethodsFive healthy subjects ages 21–65 years had 9 accelerometers and one specialized directional microphone (with modifications) applied to their lumbar region in a previously developed pattern that allowed specific localization of joint sounds. Each subject underwent full lumbar ranges of motion (ROM), lumbar SMT (left side = up‐side), and repeated full ROM; all while recordings were made from the accelerometers and microphone. Accelerometer and microphone data were assessed for cavitations and crepitus.ResultsVibration and acoustic methods were successfully implemented and provided complementary information that identified cavitations, crepitus, and verified artifacts. Ten cavitations and 1 crepitus were recorded from 7 joints (all left side). Three instances of multiple joint cavitations were identified [2 from 2 joints (L L1/L2 and L L3/L4) and 3 from 1 joint (L L1/L2)]. Some recordings identified a cavitation when inaudible to subject and clinician.ConclusionsAccelerometers and microphone provided unique and complementary information. Assessing accelerometer and acoustic data could help deepen understanding of spinal mechanics and SMT. Funding: NIH/NCCAM Grant # 3R01AT000123‐06S2.