Brachial plexus neuropathy may present as an isolated peripheral nerve lesion, suggesting local compression, when in fact the pathophysiology is a diffuse proximal inflammation. The type of management depends on an accurate diagnosis of the diffuse lesion with electromyography. A descriptive case of isolated anterior interosseus nerve palsy is presented and the literature is reviewed. Analysis of the reported cases reveals that anterior interosseus nerve palsies resulting from different etiologies are included in the same series and that treatment recommendations are highly specialty-oriented. Cases of brachial plexus neuritis-induced anterior interosseus nerve palsy should be managed conservatively, while surgical decompression may be performed for specific instances of direct trauma.