Suzy Ngomo1, Catherine Mercier2, Laurent J Bouyer2, Alexandre Savoie3, Jean-Sébastien Roy4. 1. Centre for Interdisciplinary Research in Rehabilitation and Social Integration, Quebec City, Que G1M2S8, Canada; Department of Rehabilitation, Faculty of Medicine, Université Laval, Quebec City, Que G1R1P5, Canada; Department of Health Sciences, Université du Québec à Chicoutimi, Chicoutimi, Que G7H2B1, Canada. 2. Centre for Interdisciplinary Research in Rehabilitation and Social Integration, Quebec City, Que G1M2S8, Canada; Department of Rehabilitation, Faculty of Medicine, Université Laval, Quebec City, Que G1R1P5, Canada. 3. Centre for Interdisciplinary Research in Rehabilitation and Social Integration, Quebec City, Que G1M2S8, Canada. 4. Centre for Interdisciplinary Research in Rehabilitation and Social Integration, Quebec City, Que G1M2S8, Canada; Department of Rehabilitation, Faculty of Medicine, Université Laval, Quebec City, Que G1R1P5, Canada. Electronic address: jean-sebastien.roy@rea.ulaval.ca.
Abstract
OBJECTIVE: To investigate whether rotator cuff tendinopathy leads to changes in central motor representation of a rotator cuff muscle, and to assess whether such changes are related to pain intensity, pain duration, and physical disability. METHODS: Using transcranial magnetic stimulation, motor representation of infraspinatus muscle was assessed bilaterally in patients with unilateral rotator cuff tendinopathy. RESULTS: Active motor threshold is significantly larger for the affected shoulder comparatively to the unaffected shoulder (n=39, p=0.01), indicating decreased corticospinal excitability on the affected side compared to unaffected side. Further, results suggest that this asymmetry in corticospinal excitability is associated with duration of pain (n=39; r=0.45; p=0.005), but not with pain intensity (n=39; r<0.03; p>0.43). In contrast with findings in other populations with musculoskeletal pain, no significant inter-hemispheric asymmetry was observed in map location (n=16; p-values ⩾ 0.91), or in the amplitude of motor responses obtained at various stimulation intensities (n=16; p=0.83). CONCLUSION: Chronicity of pain, but not its intensity, appears to be a factor related to lower excitability of infraspinatus representation. SIGNIFICANCE: These results support the view that while cortical reorganization correlates with magnitude of pain in neuropathic pain syndromes, it could be more related to chronicity in the case of musculoskeletal disorders.
OBJECTIVE: To investigate whether rotator cuff tendinopathy leads to changes in central motor representation of a rotator cuff muscle, and to assess whether such changes are related to pain intensity, pain duration, and physical disability. METHODS: Using transcranial magnetic stimulation, motor representation of infraspinatus muscle was assessed bilaterally in patients with unilateral rotator cuff tendinopathy. RESULTS: Active motor threshold is significantly larger for the affected shoulder comparatively to the unaffected shoulder (n=39, p=0.01), indicating decreased corticospinal excitability on the affected side compared to unaffected side. Further, results suggest that this asymmetry in corticospinal excitability is associated with duration of pain (n=39; r=0.45; p=0.005), but not with pain intensity (n=39; r<0.03; p>0.43). In contrast with findings in other populations with musculoskeletal pain, no significant inter-hemispheric asymmetry was observed in map location (n=16; p-values ⩾ 0.91), or in the amplitude of motor responses obtained at various stimulation intensities (n=16; p=0.83). CONCLUSION: Chronicity of pain, but not its intensity, appears to be a factor related to lower excitability of infraspinatus representation. SIGNIFICANCE: These results support the view that while cortical reorganization correlates with magnitude of pain in neuropathic pain syndromes, it could be more related to chronicity in the case of musculoskeletal disorders.
Authors: Ali Noorani; Michael Goldring; Anju Jaggi; Jo Gibson; Jonathan Rees; Marcus Bateman; Mark Falworth; Peter Brownson Journal: Shoulder Elbow Date: 2018-12-10
Authors: Suzanne J Snodgrass; Scott F Farrell; Henry Tsao; Peter G Osmotherly; Darren A Rivett; Lucy S Chipchase; Siobhan M Schabrun Journal: J Athl Train Date: 2018-03-23 Impact factor: 2.860
Authors: René Pelletier; Daniel Bourbonnais; Johanne Higgins; Maxime Mireault; Michel Alain Danino; Patrick G Harris Journal: Rehabil Res Pract Date: 2018-08-26