[Electromyography and electroneurography in peripheral nerve lesions. Part I].

First, the possible forms of the lesion of peripheral nerves are defined in the form of a survey: pressure damage (neurapraxia), axon interruption with maintained envelope structures (axonotmesis) and complete separation of the nerve (neurotmesis). From these, the various prognostic characteristics of a nerve lesion can be derived. An neurological examination is not sufficient for a thorough study of these phenomena. A particularly valuable aid is offered by the neuroelectrodiagnostic methods of electromyography and electroneurography. The technical fundamentals of these are briefly dealt with by the authors and indications are derived from them for the use of the two methods. In case of the open nerve lesion, the methods are used for a demonstration of intact nerve fibres, and, in the later phase, for the proof of returning spontaneous activity as well as the degree of the progress of a reinnervation. As far as chronic pressure damage is concerned, for example in bottle-necks, information regarding the seat and the degree of the nerve damage can be derived. And finally, EMG and ENG permit to make statements about the segmental height of radicular damage; this is necessary in case of plexus damage, but also for the demarcation of distal lesions. In the second part, the combination with the clinical practice and therapy will be dealt with in greater detail.