The office evaluation of weakness can be a daunting task. Many different disorders affecting many different parts of the nervous system can manifest with "weakness," and several nonneurologic conditions may present with complaints of weakness. It is the job of the neurologist to determine whether a patient has neurologic weakness or suffers simply from fatigue. The physician then must properly ...

Three patients presented with focal weakness of an arm which followed segmental herpes zoster affecting the same limb. Neurophysiological investigations suggest that the site of the lesion lay at the root, plexus, or peripheral nerve level. This reflects the various ways in which the virus may affect the peripheral nervous system.