Peripheral nerve and muscle ultrasound in amyotrophic lateral sclerosis

Introduction: High‐resolution ultrasound has been used to evaluate several neuromuscular conditions, but it has only been used on a limited basis in amyotrophic lateral sclerosis (ALS) patients. It has not been used to assess their peripheral nerves. This study was designed to use neuromuscular ultrasound to investigate nerve cross‐sectional area and muscle thickness in ALS. Methods: Twenty individuals with ALS and 20 matched controls underwent neuromuscular ultrasound to measure the cross‐sectional area of their median and sural nerves and the thickness of their biceps/brachialis muscle complex. Results: The cross‐sectional area of the median nerve in the mid‐arm was smaller in the ALS group than in controls (10.5 mm2 vs. 12.7 mm2, P = 0.0023), but no difference was seen in the sural nerve (4.5 mm2 vs. 5.0 mm2, P = 0.1927). The ALS group also had thinner biceps/brachialis than controls (2.1 cm vs. 2.9 cm, P = 0.0007). Conclusions: Neuromuscular ultrasound demonstrates nerve and muscle atrophy in ALS and should be further explored as a disease biomarker. Muscle Nerve 44: 346–351, 2011