Background: It has generally been assumed that spinal manipulation has the biomechanical effect of increasing spinal range of motion. Past research has shown that there are likely no lasting changes to passive range of motion, and it is unclear whether there is an increase in active range of motion after manipulation.
Objective: To study changes in active cervical range of motion after spinal manipulation of the cervical spine.
Design: A double-blind randomized controlled trial at the outpatient clinic Phillip Chiropractic Research Centre, RMIT University, Melbourne, Australia.
Methods: One hundred five patients with cervicogenic headache were randomized into 2 groups. After a baseline observation period, Group 2 received manipulation (toggle recoil) to the cervical spine, whereas Group 1 received sham manipulation. In the next trial phase, Group 1 received manipulation, whereas Group 2 received no treatment. This was followed by the final trial phase, in which Group 2 received sham manipulation and Group 1 received no treatment. After each trial phase, active range of cervical motion was measured with a strap-on head goniometer by 2 blinded examiners.
Results: After receiving spinal manipulation, active range of motion in the cervical spine increased significantly (P < .0006) in Group 2 compared with Group 1, and this difference between the treatment groups disappeared after the third trial phase in which Group 1 also received manipulation, as expected.
Conclusion: Spinal manipulation of the cervical spine increases active range of motion.