Whitman Dalton, Sillevis Rob, Frommelt Matthew
Department of Rehabilitation Sciences, Florida Gulf Coast University, Fort Myers, FL 33965, USA.
Life (Basel). 2025 Jan 15;15(1):103. doi: 10.3390/life15010103.
High-velocity, low-amplitude (HVLA) manipulation is a common manual therapy technique used for treating pain and musculoskeletal dysfunction. An audible manipulation sound is commonly experienced by patients who undergo HVLA manipulation; however, there is little known about the effects and clinical relevance of the audible manipulation sound on cortical output and the autonomic nervous system. This study aimed to identify the immediate impact of the audible manipulation sound on brainwave activity and pupil diameter in asymptomatic subjects following an HVLA cervical manipulation.
40 subjects completed this quasi-experimental repeated measure study design. Subjects were connected to electroencephalography and pupillometry simultaneously, and an HVLA cervical distraction manipulation was performed. The testing environment was controlled to optimize brainwave and pupillometry data acquisition. Pre-manipulation, immediately after manipulation, and post-manipulation data were collected. The presence of an audible manipulation sound was noted.
Twenty subjects experienced an audible manipulation sound. Brainwave activity changes were significant ( < 0.05) in both the audible manipulation sound and non-manipulation sound groups. Pupil diameter changes ( < 0.05) occurred in both eyes of the non-manipulation sound group and in the left eye of the audible-manipulation sound group. Brainwave activity patterns were similar in both groups.
The presence of an audible manipulation sound is not required to produce central nervous system changes following an HVLA cervical manipulation; however, the audible manipulation sound does prolong the effects of brainwave activity, indicating a prolonged relaxation effect.
高速低幅（HVLA）手法是一种用于治疗疼痛和肌肉骨骼功能障碍的常见手法治疗技术。接受HVLA手法治疗的患者通常会听到手法操作的声音；然而，关于这种可听到的手法操作声音对皮质输出和自主神经系统的影响及临床相关性却知之甚少。本研究旨在确定HVLA颈椎手法操作后，可听到的手法操作声音对无症状受试者脑电活动和瞳孔直径的即时影响。
40名受试者完成了这项准实验性重复测量研究设计。受试者同时连接脑电图和瞳孔测量仪，然后进行HVLA颈椎牵引手法操作。控制测试环境以优化脑电和瞳孔测量数据采集。收集手法操作前、操作后即刻和操作后的数据。记录是否有可听到的手法操作声音。
20名受试者听到了手法操作声音。可听到手法操作声音组和未听到手法操作声音组的脑电活动变化均具有显著性（P<0.05）。未听到手法操作声音组的双眼和听到手法操作声音组的左眼瞳孔直径发生了变化（P<0.05）。两组的脑电活动模式相似。
HVLA颈椎手法操作后产生中枢神经系统变化并不需要有可听到的手法操作声音；然而，可听到的手法操作声音确实会延长脑电活动的影响，表明有延长的放松效果。
