Median nerve compression within the humeral head of pronator teres.

We describe a case of the pronator syndrome caused by compression of the median nerve by a fibrous band as the nerve passed through the humeral head of origin of pronator teres. This rare anatomical arrangement resulted in displacement of the median nerve to the anterior aspect of the medial humeral epicondyle and, as far as we are aware, has not previously been described as a site of compression neuropathy.