Twenty-seven subjects with chronic neck pain (persisting for > 3 months) and 26 healthy volunteers were examined. Subjects with organic lesion of the ear, nose, throat, eye, or central nervous system were excluded. The CCS group received IC over the maximal tender points of the origin of the posterior nuchal muscle. Sensory organization test (SOT) scores, cervical range of motion (ROM), and isometric strength of neck were measured before IC and after IC.
The ROM of the cervical spine increased in all directions after IC (P < .0083) in the CCS group, and isometric strength in the CCS group rose in all directions after IC (P = .000). There was a significant difference in ankle strategy score under the sway-referenced vision and fixed support condition (P = .003) between the control group and CCS before IC. The ankle strategy score of the CCS group improved substantially after IC under eyes closed and sway-referenced support conditions (P = .003). The visual and vestibular ratios in the CCS group also increased after IC (P = .006 and P = .002, respectively).
The findings of this study showed that ROM of the cervical spine and isometric strength increased in all directions, and the SOT scores showed increased postural stability under conditions with swayed reference support after IC in the CCS group. The ratios for vestibular and visual function also increased after IC in the CCS group.