Evaluation Method of Immediate Effect of Local Vibratory Stimulation on Proprioceptive Control Strategy: A Pilot Study

Postural instability owing to poor proprioception is considered a main cause of low back pain and falls. However, the effect of local vibratory stimulation on a poor proprioceptor on proprioceptive control strategy has yet to be evaluated. Therefore, in this study, we proposed an evaluation method of the immediate effect on proprioceptive control strategies by applying local vibratory stimulation to the poor proprioceptor. First, using our device, we determined the poor proprioceptors in each of six elderly patients with non-specific low back pain. Furthermore, we applied local vibratory stimulation to the poor proprioceptor. Finally, we compared the proprioceptive control strategy before and after applying local vibratory stimulation. As a result, the proprioceptive control strategy improved for three patients with impaired muscle spindles that responded to a higher frequency (p < 0.05). Thus, the impaired proprioceptive control strategy caused by a decline in the muscle spindle responding to a higher frequency might be improved by local vibratory stimulation. Furthermore, it was shown that our developed device and protocol might be used to evaluate proprioceptive control strategies within multiple frequency ranges, as well as activate a poor proprioceptor based on diagnosis and improve the proprioceptive control strategies.