Efficacy of NAGs, SNAGs and Self SNAGs for cervical spine musculoskeletal disorders (CSMD): A systematic review of the literature

Pitance, Laurent [UCL] Ysaline De Vleeshouwer Audrey Desclee Susan Armijo-Olivo

Background: Cervical spine musculoskeletal disorders (CSMD) such as mechanical neck pain, cervicogenic dizziness and cervicogenic headache (CGH) are common in the general population. They generate symptoms like pain and decrease in cervical range of motion (ROM), deficit in balance, and functional limitation. Manual Therapy (MT) has been really popular in the last decade to help manage CSMD, especially using the techniques introduced by Brian Mulligan such as Sustained Natural Apophyseal Glides (SNAGs) or Natural Apophyseal Glides (NAGs). However, a systematic evaluation of these techniques to treat CSMD has not been performed. Purpose: To provide a comprehensive overview of the effectiveness of the current literature concerning Mulligan techniques used to manage cervical spine musculoskeletal disorders. Method: Electronic data searches of 5 databases were performed, in addition to a manual search up to February 2017. Randomized controlled trials that involved adults with CSMD that compared Mulligan techniques to another treatment or to a placebo intervention were included. Two reviewers independently conducted selection, data extraction and assessment of risk of bias. Main results: We screened 1193 studies. A total of 12 studies were included in the final analysis. Studies investigated the effectiveness of Mulligan techniques in patients suffering from mechanical neck pain (4), cervical spondylosis (1), cervicogenic dizziness (4) and cervicogenic headaches (CGH) (1). Most of the included trials had unclear or high risks of bias. Significant improvement of pain intensity, range of motion and disability were reported in patients with mechanical neck pain. Intensity and frequency of the dizziness as well as disability were improved in patients with cervicogenic dizziness. Significant improvement of headache intensity, frequency and duration together with range of motion were reported in patients with CGH. Significant improvement were reported for patients with cervicogenic dizziness and CGH at long- term follow-up (12 months) Limitations: Quality of the evidence and heterogeneity of the studies were limitations of the current systematic review. Conclusions: The Mulligan techniques (SNAGs and Self-SNAGs), applied to the cervical spine, are safe and simple interventions that could potentially be beneficial for patients with cervicogenic dizziness, CGH and mechanical neck pain. Larger randomized controlled trials, using rigorous methodology, in different CSMD are warranted.