Analysis of the motor unit action potentials in patients with myofascial pain

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To compare the configurational and firing properties of motor until action potentials (MUAPs) in the masseter muscles between myofascial pain patients and asymptomatic controls at submaximal voluntary contraction levels, and to evaluate whether myofascial pain has abnormal electromyographic properties observed in neuromuscular disorders or not, I performed the below-mentioned four experiments: (1) At first, We explored the feasibility of utilizing the turns per second (TS) and amplitude per turn (AT) in conjunction with surface electrodes as a method for assessing masticatory muscle function, and results showed that the AT increased with contraction at all contraction levels, demonstrating a linear relationship, while the TS showed a nonlinear increase characterized by an initial steep rise followed by a plateau, which was simulated with a third polynomial function. We considered that the TS and AT may provide valuable physiological information about the underlying mechanisms of recrui … More tment and the firing of motor units; (2)Second, I tried to demonstrate the feasibility of utilizing electromyographic decomposing systems (ADEMG) as a means to assess oral and masticatory muscle function using concentric needle electrodes at the right masseter muscles of asymptomatic healthy females, and we reconfirmed the usefulness of the ADEMG systems up to 30% MVC in the human masseter muscles; (3)Third, I compared the configurational and firing properties of MUAPs in the masseter muscles between myofascial pain patients and asymptomatic controls at submaximal voluntary contraction levels, and I evaluated whether myofascial pain has abnormal electromyographic properties observed in neuromuscular disorders or not. Consequently, I failed to demonstrate any abnormal configurational properties of MUAPs, frequently recognized in case of neuromuscular disorders; (4)Finally, I examined whether or not Temporomandibular Disorders (TMD) patients with chronic myalgia have increased pain sensitivity at remote sites outside of the head and neck region, and to evaluate whether endogenous pain inhibitory systems triggered ischemic pain functions favorably in those patients. As a result, I guessed that TMD patients have increased pain sensitivity at remote sites, and I also provided additional evidence that the endogenous opioid systems may become impaired in TMD patients with chronic masticatory myalgia. Less