Chronic low back pain remains one of the most burdensome musculoskeletal conditions globally, and identifying which manual therapy techniques actually work — versus those that merely feel therapeutic — is a persistent clinical challenge. A rigorous pooled analysis now brings clearer signal to one widely used physiotherapy technique, offering both practitioners and patients stronger evidence for its use.
This systematic review and meta-analysis synthesized data from 17 randomized controlled trials encompassing 716 adults with chronic nonspecific low back pain (CNSLBP), published between 2015 and 2024. The focus was Mulligan sustained natural apophyseal glides (SNAGs) — a hands-on spinal mobilization technique in which a therapist applies a sustained gliding force to lumbar vertebrae while the patient performs active movement. Searches spanned seven major databases including PubMed, Scopus, Embase, and PEDro. Study quality was evaluated using both the PEDro scale (mean score 6.1, range 4–9) and the Cochrane Risk-of-Bias tool, indicating fair-to-good methodological quality with low-to-moderate overall bias risk. Random-effects meta-analyses using standardized mean differences consistently showed significant improvements in pain intensity, lumbar range of motion, and disability scores following SNAG interventions compared to sham, standard physiotherapy, or other manual therapy comparators.
This analysis arrives at a meaningful moment: the broader manual therapy literature has faced growing scrutiny over effect sizes that often dissolve when compared against credible sham controls. The SNAG technique's proposed mechanism — restoring facet joint glide kinematics to reduce pain-provoking impingement — has biological plausibility, but neurophysiological modulation likely contributes as well. Key limitations here include the modest total sample size across trials, heterogeneity in intervention dosing protocols, and the well-documented difficulty of blinding participants to hands-on treatments. The mean PEDro score of 6.1 is acceptable but not exceptional. Still, for a systematic review in the manual therapy space, 17 RCTs with consistent directional effects across multiple outcomes is a relatively robust foundation. This positions SNAGs as a credible, evidence-supported adjunct — though not a standalone solution — for managing chronic low back pain in physiotherapy settings.