Overriding fifth finger: an unusual sign in lower brachial plexopathy.

[neuralgic amyotrophy]

Hand deformities are often useful clinical signs . To our knowledge , they have not been described in association with brachial plexus lesions . A 28 -year -old female presented with sudden left shoulder pain and medial forearm parasthesia . Examination showed the left fifth finger adducting and flexing over the dorsal aspect of the fourth finger . Neurophysiological studies and MRI supported a brachial plexus lesion . The physical sign was not present 5 months post onset and the patient experienced near complete clinical improvement . The unusual physical sign occurred in association with neuralgic amyotrophy . Its occurrence can be explained in terms of transient patchy involvement of nerve fascicles in the brachial plexus .