To which degree differs active cervical range of motion between patients with neck pain, whiplash and healthy controls? A systematic review and meta-analysis.

Abstract To quantify differences in aCROM between patients with neck pain and healthy controls, in whiplash-associated disorders (WAD) and non-traumatic neck pain, and in patients with acute complaints versus those with chronic complaints. Seven bibliographic databases were searched from inception to April 2015. In addition a manual search was performed. Full papers on a numerical comparison of aCROM in patients with neck pain and healthy controls of similar ages were included. Two reviewers independently selected studies and assessed risk of bias. Two reviewers extracted the data. Pooled mean differences of aCROM were calculated using a random-effects model. The search yielded 6261 hits; Twenty-seven articles (2366 participants, 13 low risk of bias) met the inclusion criteria. The neck pain group showed less aCROM in all movement directions compared to healthy controls. Mean differences ranged from -7.04° [95% CI=-9.70°, -4.38°] for right lateral bending (11 studies) to -89.59° [95% CI= -131.67°, -47.51°] for total aCROM (4 studies). Patients with WAD had less aCROM than patients with non-traumatic neck pain. No conclusive differences in aCROM were found between patients with acute and patients with chronic complaints. Patients with neck pain have a significantly decreased aCROM compared to healthy controls and patients with WAD have less aCROM than those with non-traumatic neck pain.