Comment on "peripheral nerve function in patients with excessivefragmentary myoclonus during sleep"

We have read with interest the paper “Peripheral nerve function in patients with excessive fragmentary myoclonus during sleep,” by Raccagni and colleagues . The authors investigated the presence of peripheral nerve lesions in patients presenting with excessive fragmentary myoclonus (EFM). They performed electrophysiological studies of lower limbs in 98 patients consisting of motor nerve conduction of fibular and tibial nerves, F-wave of tibial nerve, sensory nerve conduction of sural nerve and needle electromyography of tibialis anterior muscle. They found alterations in 49 patients and they concluded that EFM is a sign of peripheral nerve disorder (in a portion of patients' samples). The paper by Raccagni and colleagues is extremely important for many reasons. The study underlines the possible causes of EFM, opens the doors to possible therapeutic approaches, appropriate patient management and specific rehabilitation programs. Furthermore, the paper shows the usefulness of diagnostic tools, which are able to support clinical evaluation. Electrodiagnosis (based on nerve conduction study and electromyography) is an objective method, which allows an extensive evaluation of the peripheral nervous system. This approach based on the use of clinical examination and additional instruments–is able to evaluate nerve function, and should be considered for routine physician practice. We would like to suggest the use of ultrasound (US) as a tool to assess the morphological features of the peripheral nervous system . This technique will evaluate the nerve and surrounding tissues, and therefore depict nerve abnormalities and anatomical variations [4]. In cases of EFM, it may be useful to evaluate differences among patients, in order to know if (and which) particular morphological signs of neuropathies are present. By using these techniques, a more accurate diagnosis may be possible. US may also allow a safe and rapid follow-up evaluation.