This Article Full Text Full Text (PDF) Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal My Folders Download to citation manager Citing Articles Citing Articles via Web of Science (2) Citing Articles via Google Scholar Google Scholar Articles by Krkovic, M. Articles by Bosnjak, R. Search for Related Content PubMed PubMed Citation Articles by Krkovic, M. Articles by Bosnjak, R.

Subperiosteal elevation of the ulnar nerve during internal fixation for fractures of the distal humerus assessed by intra-operative neurophysiological monitoring

M. Krkovi, MD, Surgeon of Traumatology¹; M. Korda, MD, PhD, Professor²; M. Tonin, MD, PhD, Senior Surgeon of Traumatology, Professor¹; and R. Bonjak, MD, PhD, Associate Professor, Neurosurgeon³

¹ Department of Traumatology
² Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Zaloka 4, 1000 Ljubljana, Slovenia.
³ Department of Neurosurgery, University Hospital Centre, Zaloka 7, 1000 Ljubljana, Slovenia.

Correspondence should be sent to Dr R. Bonjak; e-mail: Roman.Bosnjak{at}kclj.si

Ulnar nerve function, during and after open reduction and internal fixation of fractures of the distal humerus with subperiosteal elevation of the nerve, was assessed by intra-operative neurophysiological monitoring. Intermittent recording of the compound muscle action potentials was taken from the hypothenar muscles in 18 neurologically asymptomatic patients.

The mean amplitude of the compound muscle action potential after surgery was 98.1% (SD 17.6; –37% to +25%). The amplitude improved in six patients following surgery. Despite unremarkable recordings one patient had progressive paresis. Motor impairment is unlikely if the compound muscle action potential is continuously preserved and not reduced by more than 40% at the end of surgery. Temporary decreases in amplitude by up to 70% were tolerated without clinical consequences. However, repeated clinical examination is obligatory to recognise and treat early post-operative palsy.