Trunk muscle activation in low-back pain patients, an analysis of the literature.
Level 5 - mechanism / opinion, no new human data
Narrative review synthesizing theoretical models and observational literature without systematic meta-analysis.
PubMed 12832164 · doi:10.1016/s1050-6411(03)00041-5
What was done
The authors performed a literature review comparing two theoretical frameworks for motor control in low-back pain: the pain-spasm-pain model and the pain adaptation model. They evaluated neurophysiological mechanisms and tested model-derived predictions regarding lumbar extensor activation against findings retrieved from 30 clinical studies of low-back pain patients and 3 experimental pain-induction studies.
What was found
The abstract reports no numerical estimates or effect sizes. Qualitative synthesis of the 30 clinical and 3 experimental studies indicated that neither the pain-spasm-pain model nor the pain adaptation model is unequivocally supported by empirical literature. Based on activation timing and muscle load-sharing data, the authors proposed an alternative model wherein altered recruitment functions to enhance spinal stability.
Why it matters
This review challenges simplistic inhibition and spasm paradigms for low-back pain motor control. It reframes trunk muscle recruitment changes as functional adaptations aimed at preserving mechanical stability.
Limits
The abstract reports no quantitative meta-analytic metrics, effect sizes, or formal risk-of-bias grading. The narrative synthesis evaluates heterogeneous clinical and laboratory pain studies without specifying total patient sample sizes.
Cited by
- supports Muscle spasms often occur to provide artificial stability as a protective mechanism for an area of underlying muscular weakness.