Manual therapy for mechanical neck disorders: a systematic review.
Neck disorders are common, disabling and costly. Randomized trials were reviewed using a Cochrane format, to determine if manual therapy improves pain, function and patient satisfaction in adults suffering from neck disorders with and without radicular findings or headache. Sequenced computerized searches ended in December 1997. Two independent reviewers extracted data while three assessed trial quality. Standard mean difference and relative risks were translated to number needed to treat (NNT) and the percent treatment advantage. The 20 selected trials' quality was 2.4 (SD: 1.04) on the 5-point scale described by Jadad. Trials were clinically heterogenous. Manipulation alone, mobilizations alone, manipulation/mobilization and treatments including massage consistently showed similar effects to placebo, wait period or control. Multimodal manual therapy care including exercise were superior to a control, to certain physical medicine methods and to rest for pain and patient satisfaction. The NNT for a clinically important reduction in pain varied from 2 to 11 and treatment advantage from 6% to 41% at the cost of benign transient side-effects. While results remain inconclusive, some clinical themes have emerged. For mechanical neck disorder with or without headache, it appears that to be most beneficial, manual therapies should be done with exercise for improving pain and patient satisfaction. Manipulation and mobilization alone appear to be less effective. Factorial design would help delineate the magnitude of effect for each component of care.