Cutaneous silent period in myofascial pain syndrome

Introduction: Increased response to painful stimuli without spontaneous pain suggests the role of the central hyperexcitability of pain pathways in the pathogenesis of Myofascial pain syndrome (MPS). In this study, we aimed to test the hypothesis that spinal pain pathways are affected in MPS and we used cutaneous silent period (CSP) parameters to demonstrate the hyperexcitability of spinal pain pathways in MPS. Methods: Twenty-nine patients diagnosed with MPS and 30 healthy volunteers were included in the study. The CSP recordings were performed in the right upper and left lower extremities. Results: Both in the upper and lower extremities, patients had prolonged CSP latencies (p=0.034, p=0.049 respectively), shortened CSP durations (p=0.009, p=0.008 respectively). Discussion: Delayed and shortened CSP in MPS patients implies dysfunction in the inhibitory mechanism of the spinal/supra-spinal pain pathways suggesting central sensitization in the pathogenesis of MPS supporting the research hypothesis. This article is protected by copyright. All rights reserved.