An analysis on muscle tone and stiffness of posterior cervical region during sling and plinth on static prone position

[Purpose] The purpose of this study was to quantitatively analyze changes in muscle tone and stiffness in the posterior cervical region of individuals in a static prone position in a sling or on a plinth. [Subjects and Methods] Twenty-four men in their 20s were divided into a sling group and a plinth group, and their changes in muscle tone and stiffness over time in the upper cervical region, lower cervical region, and upper trapezius muscles during a static prone position were measured. [Results] The sling group showed increases in the mean values of muscle tone and stiffness in the upper cervical region immediately after the suspension. In addition, this group exhibited statistically significant declines in the muscle tone and stiffness of the upper cervical region and a statistically significant decline in the muscle tone of the upper trapezius region. [Conclusion] The findings of this study suggest that for the treatment of the posterior upper cervical region after sling suspension in a static prone position, the time required to reduce the muscle tone and stiffness of this region should be taken into account.