Sensorimotor Incongruence in People with Musculoskeletal Pain: A Systematic Review

Musculoskeletal pain has major public health implications, but the theoretical framework remains unclear. It is hypothesized that sensorimotor incongruence (SMI) might be a cause of long-lasting pain sensations in people with chronic musculoskeletal pain. Research data about experimental SMI triggering pain has been equivocal, making the relation between SMI and pain elusive. The aim of this study was to systematically review the studies on experimental SMI in people with musculoskeletal pain and healthy individuals.

Preferred reporting items for systematic reviews and meta-analyses guidelines were followed. A systematic literature search was conducted using several databases until January 2015. To identify relevant articles, keywords regarding musculoskeletal pain or healthy subjects and the sensory or the motor system were combined. Study characteristics were extracted. Risk of bias was assessed using the Dutch Institute for Healthcare Improvement (CBO) checklist for randomized controlled trials, and level of evidence was judged.

Eight cross-over studies met the inclusion criteria. The methodological quality of the studies varied, and populations were heterogeneous. In populations with musculoskeletal pain, outcomes of sensory disturbances and pain were higher during all experimental conditions compared to baseline conditions. In healthy subjects, pain reports during experimental SMI were very low or did not occur at all.

Based on the current evidence and despite some methodological issues, there is no evidence that experimental SMI triggers pain in healthy individuals and in people with chronic musculoskeletal pain. However, people with chronic musculoskeletal pain report more sensory disturbances and pain during the experimental conditions, indicating that visual manipulation influences pain outcomes in this population.