en Original Original <p dir="ltr" style="text-align: justify;"><strong>Introduction:</strong> Cervical rib is relatively uncommon congenital abnormality that originates from&nbsp;the seventh cervical vertebrae and rarely from the sixth vertebrae. The purpose of this paper is to&nbsp;consider that this abnormal condition is an important cause of neurovascular compression at the&nbsp;thoracic outlet.<br> <strong>Methods:</strong> In this study all patients who were referred to radiology department of Isfahan&nbsp;hospitals (Iran) for chest X-ray or other cervical films, for any reasons, were evaluated for&nbsp;cervical rib and anyone who had this abnormality was entered in this study. Here, we performed&nbsp;Nerve Conduction Velocity Test (NCV) and Doppler sonography, depending on the vascular or<br> neurological symptoms.<br> <strong>Results: </strong>The results of this study show that the incidence of the neurological compression was&nbsp;higher than vascular compression. In addition, the prevalence of neurological complication in&nbsp;female was high (85.7%) and a significant percentage of them were above 30 years.<br> <strong>Conclusion:</strong> Cervical rib occurs more commonly in women and have different prevalence rates in&nbsp;different ethnic populations. Moreover, a high percentage of them have neurological complication&nbsp;which is a symptom of thoracic outlet syndrome.</p> Cervical ribs, Thoracic outlet syndrome, Neurovascular syndrome 111 114 http://anatomyjournal.ir/browse.php?a_code=A-10-106-1&slc_lang=en&sid=1 Gholamreza Dashti Dashti@med.mui.ac.ir 10031947532846001152 10031947532846001152 No Department of Anatomical Sciences, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran. Nazem Ghasemi ghasemi_anatomy@yahoo.com 10031947532846001153 10031947532846001153 Yes Department of Anatomical Sciences, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.