Study design and objectives: Meta-analysis of randomized controlled trials to evaluate the effectiveness of the McKenzie method for low back pain (LBP).
Summary of background data: The McKenzie method is a popular classification-based treatment for LBP. The faulty equation of McKenzie to extension exercises (generic McKenzie) is common in randomized trials.
Methods: MEDLINE, EMBASE, PEDro, and LILACS were searched up to August 2003. Two independent reviewers extracted the data and assessed methodologic quality. Pooled effects were calculated among homogeneous trials using the random effects model. A sensitivity analysis excluded trials reporting on generic McKenzie.
Results: Eleven trials of mostly high quality were included. McKenzie reduced pain (weighted mean difference [WMD] on a 0- to 100-point scale, -4.16 points; 95% confidence interval, -7.12 to -1.20) and disability (WMD on a 0- to 100-point scale, -5.22 points; 95% confidence interval, -8.28 to -2.16) at 1 week follow-up when compared with passive therapy for acute LBP. When McKenzie was compared with advice to stay active, a reduction in disability favored advice (WMD on a 0- to 100-point scale, 3.85 points; 95% confidence interval, 0.30 to 7.39) at 12 weeks of follow-up. Heterogeneity prevented pooling of studies on chronic LBP as well as pooling of studies included in the sensitivity analysis.
Conclusions: There is some evidence that the McKenzie method is more effective than passive therapy for acute LBP; however, the magnitude of the difference suggests the absence of clinically worthwhile effects. There is limited evidence for the use of McKenzie method in chronic LBP. The effectiveness of classification-based McKenzie is yet to be established.