Utility of Amplitudes of Positive Sharp Waves and Fibrillation Potentials

Objective: Fibrillation potentials and positive sharp waves are pathologic spontaneous potentials which originate disconnection anywhere betweenanterior hornof medulla spinalisto muscle fiber in the motor unit. In clinical practice, the presence and if present the intensity of the spontaneous denervation potentials has been evaluated. In this study, the relations between their amplitudes and parameters like lesion duration, lesion type, level of lesion, age of patient and size of recorded muscle were aimed to be examined beside the presence of spontaneous denervation potentials. Patients and Method: Amplitudes of spontaneous potentials were evaluated in patients who were referred for electrophysiological investigation withcomplaints like motor loss and/or pain and able to declare the exact time of their complaintsexcept with causes of muscle or neuromuscular disease. Results: The most common lesion sites were theperipheralnerve (45.4%)andthe radix(36.4%), the mostcommonetiologieswere discherniation(33.9%) andtrauma(32.1%). The amplitudes of both fibrillation potentials and positive sharp waves were found to be significantly correlated with male gender (pfib=0.016 and ppsw=0.014) and disease duration (pfib=0.005 and ppsw=0.021). Conclusion: Amplitudes of both fibrillation and positive sharp waves were lower in patients with disease duration of longer than two months. The amplitudes of spontaneous denervation potentials may be used as a confidential marker of chronicity since muscle fiber atrophy which develops following long term denervationmuscle fibers atrophymaygenerate lowamplitude denervation potentials.