Leonardo Gizzi1,2, Oliver Röhrle1, Frank Petzke2, Deborah Falla2,3. 1. Institute of Applied Mechanics (Civil Engineering), Chair II, Continuum Biomechanics and Mechanobiology Research Group, University of Stuttgart, Stuttgart, Germany. 2. Pain Clinic, Center for Anesthesiology, Emergency and Intensive Care Medicine, University Hospital Göttingen, Göttingen, Germany. 3. Centre of Precision Rehabilitation for Spinal Pain (CPR Spine), School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, UK.
Abstract
BACKGROUND: Actigraphy is a quantitative method for the investigation of human physical activity and is normally based on accelerometric and/or kinematic data. METHODS: A multichannel actigraphy system, able to record both acceleration and spine angles, was employed in this study to measure the quality of movement in 17 individuals with chronic low back pain (LBP) and 18 healthy individuals during unrestricted daily activities. An indication of movement complexity was computed by means of non-negative matrix factorization throughout the 24 hr period and in the 60 min of highest activity. RESULTS: Movement complexity differed only when the 60 min of highest activity was taken into account, with the LBP group showing reduced complexity (e.g., for dimensionality = 8, over 90% of the comparisons showed a significant reduction in the LBP group). CONCLUSIONS: The results are compatible with the hypothesis that pain induces a reduction in the available kinematic trajectories and degrees of freedom during natural movements, which becomes more evident when more demanding tasks are performed. A reduced movement complexity suggests a persistent alteration of the descending neural pathways and/or a disrupted somatosensory information processing, which could be possibly contrasted by administering highly variable motor tasks. SIGNIFICANCE: People with chronic pain move differently. Movement quality is difficult to evaluate during daily activities, yet it may prove more informative than quantitative measurements. We proposed a new approach for computing movement complexity and found out that patients' movements get more stereotyped when higher spinal acceleration is required.
BACKGROUND: Actigraphy is a quantitative method for the investigation of human physical activity and is normally based on accelerometric and/or kinematic data. METHODS: A multichannel actigraphy system, able to record both acceleration and spine angles, was employed in this study to measure the quality of movement in 17 individuals with chronic low back pain (LBP) and 18 healthy individuals during unrestricted daily activities. An indication of movement complexity was computed by means of non-negative matrix factorization throughout the 24 hr period and in the 60 min of highest activity. RESULTS: Movement complexity differed only when the 60 min of highest activity was taken into account, with the LBP group showing reduced complexity (e.g., for dimensionality = 8, over 90% of the comparisons showed a significant reduction in the LBP group). CONCLUSIONS: The results are compatible with the hypothesis that pain induces a reduction in the available kinematic trajectories and degrees of freedom during natural movements, which becomes more evident when more demanding tasks are performed. A reduced movement complexity suggests a persistent alteration of the descending neural pathways and/or a disrupted somatosensory information processing, which could be possibly contrasted by administering highly variable motor tasks. SIGNIFICANCE: People with chronic pain move differently. Movement quality is difficult to evaluate during daily activities, yet it may prove more informative than quantitative measurements. We proposed a new approach for computing movement complexity and found out that patients' movements get more stereotyped when higher spinal acceleration is required.
Authors: Per Kjaer; Alice Kongsted; Inge Ris; Allan Abbott; Charlotte Diana Nørregaard Rasmussen; Ewa M Roos; Søren T Skou; Tonny Elmose Andersen; Jan Hartvigsen Journal: BMC Musculoskelet Disord Date: 2018-11-29 Impact factor: 2.362