The aim of this study was to evaluate and compare the effects of two manual therapy interventions on cervical spine range of motion (ROM), head repositioning accuracy and balance, in patients with chronic cervicogenic dizziness. A randomized controlled trial with 12-week follow-up using blinded outcome assessment was conducted at a University in New South Wales, Australia. (N=86; mean ± SD age 62.0 ± 12.7 years; 50% women) with chronic cervicogenic dizziness participated in the study. Participants were placed at random to one of three groups: sustained natural apophyseal glides (SNAGs) with self-SNAG exercises, passive joint mobilization (PJM) with ROM exercises, or a placebo. Participants each received 2-6 treatments over six weeks. Cervical ROM, head repositioning accuracy, and balance were the primary outcome measures. SNAG therapy produced an improved (p≤0.05) cervical spine ROM in all six physiological cervical spine movement directions immediately post-treatment and at 12 weeks. Treatment with PJM yielded an improvement in one of the six cervical movement directions post-treatment, and one movement direction at 12 weeks. There was a greater improvement (p<0.01) after SNAGs than PJM in extension (mean difference -7.5 degrees, 95% CI -13, -2.0) and right rotation (-6.8, -11.5, -2.1) post treatment. Manual therapy had no effect on balance or head repositioning accuracy.
The study found SNAG treatment to improve cervical ROM and the effects were maintained for 12 weeks post treatment. PJM had very limited impact on cervical ROM. There was no conclusive effect of SNAGs or PJMs on joint repositioning accuracy or balance in persons with cervicogenic dizziness.