[Anterior interosseous nerve syndrome. Electromyographic characteristics (2 cases) and review of the literature (62 cases)].

The anterior interosseous nerve syndrome is a rare entrapment neuropathy of the median nerve. It is a pure motor deficit characterized by pinch loss. Anterior interosseous nerve lesions are easily assessed by EMG. The data from literature being incomplete in a majority of cases (85%), we propose EMG criteria to assert the presence of an anterior interosseous nerve syndrome and to exclude other diagnoses. The study of the anterior interosseous nerve in 20 healthy patients shows that the difference in motor potential latency between the healthy and the non-healthy side is the most predictive stimulo-detection sign. Detection, however, remains the most important element for diagnosis.