Thoracic outlet syndrome (TOS) is a complex of symptoms that occur when subclavian artery, vein and brachial plexus become subject to pressure at the superior thorax outlet. In this paper principally, attempt was made to scrutinize the physiopathology of the peripheral nerve lesion and analysis methods. Lowest level of a nerve injury is an injury where there is no damage in the nerves but it causes interruption in the signal conduction, and it is referred to as neurapraxia. Second level is the injury where the connective tissue is sound but it causes interruption in the axons within the nerve cell and it is referred to as axonotmesis. The third level of the injury is the injury that inflicts damage on both the axons and the connective tissue whereby obliterating the nerve integrity completely and it is referred to as neurotmesis. The degeneration observed through the disruption of the peripheral nerve is called Waller degeneration. They are the findings observed more frequently in neurapraxia and less frequently in axonotmesis, and neurotmesis TOS as a result of nerve pressures and compactions.In TOS, in order to evaluate the nerve pressure, electroneuromyography (ENMG) findings are important. Motor neuron disease, radiculopathy, plexopathy, peripheral nerve lesion, peripheral neuropathy, entrapment neuropathy, neuromuscular junction disease and myopathies are present among the diseases that can be evaluated through electroneuromyography ENMG. In EMG, the examinations that are interference patern, analysis during rest, motor unit potentials (MUP) examination and motor unit participation (recruitment) analysis distinguish myopathy and denervation from each other. In the TOS diagnosis, tests like nerve conduction velocity works (NCV), F response, and Hoffman (H) reflex are used. Ulnar nerve's normal conduction rate is 72 m/sec and more at the thoracic outlet. Values under 70 m/sec show the nerve pressure on TOS. When the ulnar nerve conduction rate is below 55-60 m/sec, surgical treatment can be considered.
Key words: Neuropraxia, neuropathy, injury
ÖzetTorasik çıkış sendromu (TOS), subklavian arter, ven ve brakiyal pleksusun superior toraks çıkışında basıya uğra-masıyla ortaya çıkan semptomlar kompleksidir. Bu yazıda esas olarak periferik sinir lezyonunun fizyopatolojisi ve analiz yöntemleri incelenmeye çalışılmıştır. Sinir hasarının en düşük derecesi, sinirlerde hasar olmayan fakat sinyal iletiminin aksamasına neden olan ve nöropraksi olarak adlandırılan bir hasardır. İkinci derecesi, bağ dokusu sağlam olan fakat sinir hücresindeki aksonların kesintiye uğramasına neden olan ve aksonotmezis olarak adlandırılan hasardır. Üçüncü derece hasar, hem aksonların hem de bağ dokusunu hasara uğrata-rak sinir bütünlüğünü tamamen bozan ve nörotemezis olarak adlandırılan bir hasardır. Periferik sinirin kesisi ile görülen dejenerasyona Waller dejenerasyonu adı verilir. Daha sık-lıkla nöropraksi ve daha az olmakla birlikte aksonotmezis ve nörotemezis TOS'da görülen sinir basıları ve sıkışmaları sonucu görülen bulgulardı...