To explore the potential of sonographic muscle thickness measurement to demonstrate the presence and the pattern of muscle atrophy in various neuromuscular disorders, and to determine the correlations of muscle thickness with clinical and electrophysiological measures.

We performed a prospective study from March to August 2018 of  patients attending the neuromuscular clinic. All patients underwent clinical evaluation and standardized muscle thickness measurement by ultrasound in 7 muscles. 

The study cohort consisted of 114 subjects , including patients with polyneuropathy, motor neuron disease and myopathy. The smallest distal muscle thickness was found in patients with polyneuropathy, while the smallest proximal muscle thickness was found in patients with myopathy. Muscle thickness was strongly correlated with muscle strength (r2 = 0.62), electrophysiological findings (r2: 0.44-0.55), and disability score (r2 = 0.53). 

Standardized muscle thickness measured by ultrasound shows diagnostic usefulness in a vast spectrum of neuromuscular disorders and correlates with clinical and electrophysiological findings.