Sonographic evaluation of common peroneal neuropathy in patients with foot drop.

The common peroneal nerve arises from the sciatic nerve and is subject to a variety of abnormalities. Although diagnosis is often is based on the clinical findings and electrodiagnostic tests, high-resolution sonography has an increasing role in determining the type and location of common peroneal nerve abnormalities and other peripheral nerve disorders. This article reviews the normal sonographic appearance of the common peroneal nerve and the findings in 21 patients with foot drop related to common peroneal neuropathy.