• lumbar multifidus dysfunction
• back
• pain
• strengthening
• rehabilitation

Regarding the article “Effects of three different training modalities on the cross sectional area of the lumbar multifidus in patients with chronic low back pain”,¹ I would like to extend my appreciation to Dr Danneels and his colleagues for their interest in contributing to the literature on this important and clinically relevant topic. Unfortunately, there are important design and methodological flaws inherent in this study which call into question its results and primary conclusions. I respectfully submit this review of the study, its findings, and the authors' clinical recommendations.

The objective of the investigation of Danneels et al was to determine the potential for different exercise models to reverse the pathology related atrophy of the lumbar multifidus muscle in people with low back pain. As described by various researchers, the lumbar multifidus experiences a number of morphological and neurophysiological changes following low back injury.^2–4 One of these changes is a segmental atrophy which develops at the level of pathology, on the symptomatic side and as quickly as 24 hours after the injury.³ Further, these changes have been shown to persist beyond the resolution of symptoms,⁵ and for at least five years after surgical intervention for intervertebral disc herniation.⁴ There is evidence that such findings are indicative of a …