An international consensus on gaps in mechanisms of forced-based manipulation research: findings from a nominal group technique.

Force-Based Manipulation (FBM) including light touch, pressure, massage, mobilization, thrust manipulation, and needling techniques are utilized across several disciplines to provide clinical analgesia. These commonly used techniques demonstrate the ability to improve pain-related outcomes; however, mechanisms behind why analgesia occurs with these hands-on interventions has been understudied. Neurological, neuroimmune, biomechanical, neurovascular, neurotransmitter, and contextual factor interactions have been proposed to influence response; however, the specific relationships to clinical pain outcomes has not been well established. The purpose of this study was to identify gaps present within mechanism-based research as it relates to FBM. An international multidisciplinary nominal group technique (NGT) was performed and identified 37 proposed gaps across eight domains. Twenty-three of these gaps met consensus across domains supporting the complex multisystem mechanistic response to FBM. The strength of support for gaps within the biomechanical domain had less overall support than the others. Gaps assessing the influence of contextual factors had strong support as did those associating mechanisms with clinical outcomes (translational studies). The importance of literature investigating how FBM differs with individuals of different pain phenotypes (pain mechanism phenotypes and clinical phenotypes) was also presented aligning with other analgesic techniques trending toward patient-specific pain management (precision medicine) through the use of pain phenotyping.

Self-reports vs. physical measures of spinal stiffness.

BACKGROUND: Objectively measured reduction in lumbar posterior-to-anterior (PA) stiffness is associated with pain relief in some, but not all persons with low back pain. Unfortunately, these measurements can be time consuming to perform. In comparison, the Lumbar Spine Instability Questionnaire (LSIQ) is intended to measure spinal instability and the Lumbar Spine Disability Index (LSDI) is created for self-reporting functional disability due to increased spinal stiffness. Given the above, the aim of this study is to compare measures of the LSIQ and LSDI with objective measures of lumbar PA stiffness as measured by a mechanical device, Vertetrack (VT), in patients with persistent non-specific low back pain (nsLBP). METHODS: Twenty-nine patients with nsLBP completed the LSIQ and LSDI at baseline and after two weeks. On these same occasions, PA spinal stiffness was measured using the VT. Between measurements, patients received four sessions of spinal manipulation. The resulting data was analyzed to determine the correlation between the self-report and objective measures of stiffness at both time points. Further, the patients were categorized into responders and non-responders based on pre-established cut points depending on values from the VT and compared those to self-report measures in order to determine whether the LSIQ and the LSDI were sensitive to change. RESULTS: Twenty-nine participants completed the study. Measures from the LSIQ and LSDI correlated poorly with objectively measured lumbar PA stiffness at baseline and also with the change scores. The change in objectively measured lumbar PA stiffness following spinal manipulation did not differ between those who improved, and those who did not improve according to the pre-specified cut-points. Finally, a reduction in lumbar PA stiffness following intervention was not associated with improvement in LSIQ and LSDI outcomes. CONCLUSIONS: The current data indicate that the LSIQ and LSDI questionnaires do not correlate with measures obtained objectively by VT. Our results suggest that these objective and self- reported measures represent different domains and as such, cannot stand in place of one another.