As one of the most well-known methods for treating low back pain, the McKenzie Method is still commonly used by physiotherapists worldwide. even though previous studies in the 2000's and earlier showed that there is a lack of evidence supporting its use. Over the past decade, more studies have been conducted, and recently Tam et al. (2018) released a new systematic review and meta-analysis on the subject.
So what does the most recent evidence say? Should we throw out this method? From the Physiopedia report: "The McKenzie Method is not clinically superior to all interventions in treating acute LBP but is more effective at reducing pain intensity when compared to manual therapy and exercise combined. [For chronic pain, the] McKenzie Method was more effective at reducing pain and disability than “other” interventions...more effective at reducing disability but not pain when compared to exercise alone, [and] more effective than a combined exercise, manual therapy and education intervention."
Given this conclusion, the McKenzie Method should still be considered as one of many possible treatment methods for LBP. As with any other method, it should be taken with a grain of salt, and with the knowledge that it does not address the biopsychosocial side of back pain.
Read the Physiopedia summary report here.