[The importance of electrographic investigations for the diagnosis and treatment of acroparesthesias (author's transl)].

Acroparesthesias may develop as a result of various pathological processes which affect the nerves of the hand. Usually the diagnosis can be made from the history and the clinical findings. If objectifiable neurological findings are lacking, electrographic investigations must be carried out. If several diseases are present, electrography (stimulation and myography) is particularly important for diagnosis and therapy. In compression of the median nerve in the carpal tunnel, the speed of sensory conduction is delayed in about 85%, an anomalous motor latent duction is delayed in about 70%. A distal motor latency of the median nerve of more than 8 m/sec is an absolute indication for a surgical intervention. Signs of denervation of the thenar muscles also required operative treatment.