P72-F Electromyography in the course of amyotrophic lateral sclerosis

Abstract

Background Amyotrophic lateral sclerosis is a progressive, incurable neurodegenerative disease resulting in neurogenic muscle damage. Material and methods The study covered 20 patients – 5 women and 15 men aged 43–85; 65.5 on average. The group included patients with clinically proven or probable ALS diagnosis established based on the modified El Escorial criteria. The study was performed three times with three-month long intervals. Muscles from three layers of the central nervous system were subject to analysis: bulbs (muscle of the tongue), cervical (left biceps brachii – BB and left first dorsal interosseous – FDI), sacrolumbar (right vastus lateralis – VL and right tibialis anterior – TA). Resting activity and MUP parameters (amplitude, area, duration, size index – SI) were evaluated. Results Incorrect results most frequently concerned the amplitude, area, SI MUP – BB (100%), FDI (100% – SI; 95% – the MUP amplitude; 90% – the MUP area), VL (90% – the MUP amplitude and area; 80% – SI), TA (95% – SI; 85% – the MUP amplitude and area) and duration – BB (85%), FDI (90%). Moreover, at rest, the majority of patients had, in all the muscles subject to the study, their active denervation potentials recorded, i.e. fibrillation or positive slow waves. Significant differences were observed within the course of a six-month period as regards the measurements concerning the duration of MUP of the muscles subject to the study (prolonged duration of MUP). Conclusion Neurogenic lesions are already present at the time of ALS diagnosis.Relationship was observed between motor neurons loss and the gradually increasing duration of MUP of particular muscles in the course of ALS.