Unilateral diaphragmatic paralysis and segmental motor paresis following herpes zoster

We report the case of a 73-year-old woman who complained of acute onset of pain and weakness of her left shoulder and proximal arm muscles 3 weeks after a diagnosis of herpes zoster. Electromyography revealed involvement of the C5-6 myotomes and the upper trunk of the brachial plexus. Chest X-ray and electromyographic studies documented paralysis of the left diaphragm. One year after onset, muscle strength returned to normal, but radiographic and electrophysiologic findings of diaphragm paralysis were unchanged.