Physiological effects of a CV4 cranial osteopathic technique on autonomic nervous system function: A preliminary investigation

Abstract 

Background and objectives

Research conducted in the field of cranial manipulation has primarily focused on inter- and intra-reliability detecting both the Cranial Rhythmic Impulse and cranial dysfunction. Limited literature exists regarding the effects of cranial manipulation on health outcomes, and little has been done to investigate the physiological effects of the techniques in practice. The aim of this pilot study was to investigate the physiological effects resulting from the administration of a single cranial technique (CV4) compared with simple touch.

Methods

Heart rate variability, respiration rate, galvanic skin resistance and skin temperature were measured in ten subjects (six females, four males) in an experiment consisting of five generic phases. These phases consisted of baseline, touch only, intervention (CV4), touch only and baseline. During the intervention phase, a registered osteopathic practitioner applied the CV4 technique commonly used in cranial manipulation. Changes in outcomes between each of the five phases were analysed for each dependent variable.

Results

The results of this study demonstrated that the application of the CV4 technique when compared to simple touch in asymptomatic individuals had minimal physiological effect in any of the autonomic variables recorded. No significant differences were observed in any variable across the five phases. On examination of heart rate variability, it became apparent that three subjects may have responded in a manner that was consistent with an increase in parasympathetic activity during the treatment phase. This identification leads to the notion that there may be both ‘responders’ and ‘non-responders’ to cranial treatment.

Conclusions

This pilot study fails to support the theorised effects of the CV4 technique that are commonly described. In response to application of the technique there were minimal physiological changes observed in the autonomic measures investigated. Additional research is required if the hypothesised physiological effects of techniques used in the field of cranial manipulation are to be demonstrated in the laboratory setting.

Keywords: Osteopathy, Cranial manipulation, CV4, Physiological effect, Autonomic nervous system