Clinico-diagnostic features of neuralgic amyotrophy in childhood

Neuralgic amyotrophy (NA), even known as Personage-Turner's syndrome (PTS), is a neurologic condition, affecting the lower motor neurons of brachial plexus and/or individual nerves or nerve branches, characterized by pain, muscle weakness/atrophy, and sensory symptoms. NA has an acute/subacute onset, after an infection or vaccination; it is more common in male and is rare in the pediatric population. The etiology remains uncertain, being considered heterogeneous and multifactorial. A severe acute neurologic pain around the shoulder girdle is the classic presenting symptom at onset. As the pain subsides, weakness and paresis develop. NA is usually unilateral, but sometimes, a subclinical contralateral limb involvement could be present and bilateral affection has been described. The diagnosis is clinical, through a comprehensive history and neurological examination. However, electrophysiological testing and imaging are critical, because there is no diagnostic test for PTS and it remains a diagnosis of exclusion. Upper brachial plexus peripheral involvement with weakness of periscapular and perihumeral muscles is the classic presentation, associated with electrophysiological evidence of denervation in the affected muscles. Imaging, laboratory, and genetic testing can be useful for the differential diagnosis. NA is in most cases a self-limiting condition, and it is characterized by good recovery. Treatment of NA usually involves a combination of corticosteroids, analgesics, immobilization, and physical therapy, even if limited data are available in children. Physiotherapy is required to maintain muscle strength.