A Feasibility Study to Assess Vibration and Sound From Zygapophyseal Joints During Motion Before and After Spinal Manipulation

Abstract

Objective This feasibility study used novel accelerometry (vibration) and microphone (sound) methods to assess crepitus originating from the lumbar spine before and after side-posture spinal manipulation (SMT). Methods This study included 5 healthy and 5 low back pain (LBP) subjects. Nine accelerometers and 1 specialized directional microphone were applied to the lumbar region, allowing assessment of crepitus. Each subject underwent full lumbar ranges of motion (ROM), bilateral lumbar SMT, and repeated full ROM. Following full ROMs the subjects received side-posture lumbar SMT on both sides by a licensed doctor of chiropractic. Accelerometer and microphone recordings were made during all pre- and post-SMT ROMs. Primary outcome was a descriptive report of crepitus prevalence (average number of crepitus events/subject). Subjects were also divided into 3 age groups for comparisons (18–25, 26–45, and 46–65 years). Results Overall, crepitus prevalence decreased pre-post SMT (average pre= 1.4 crepitus/subject vs. post= 0.9). Prevalence progressively increased from the youngest to oldest age groups (pre-SMT= 0.0, 1.67, and 2.0, respectively; and post-SMT= 0.5, 0.83, and 1.5). Prevalence was higher in LBP subjects compared to healthy (pre-SMT-LBP= 2.0, vs. pre-SMT-healthy= 0.8; post-SMT-LBP= 1.0 vs. post-SMT-healthy= 0.8), even though healthy subjects were older than LBP subjects (40.8 years vs. 27.8 years); accounting for age: pre-SMT-LBP= 2.0 vs. pre-SMT-healthy= 0.0; post-SMT-LBP= 1.0 vs. post-SMT-healthy= 0.3. Conclusions Our findings showed that a larger study is feasible. Other findings included that crepitus prevalence increased with age, was higher in LBP than healthy subjects, and overall decreased following SMT. This study showed that crepitus assessment using accelerometers has the potential of being an outcome measure/biomarker for assessing spinal joint (facet/Z joint) function during movement and the effects of LBP treatments (eg, SMT) on Z joint function.