ABSTRACT
PURPOSE: The subclavius posticus muscle (SPM) is an aberrant muscle, and the presence of the SPM has a clinical significance, since the SPM might lead to thoracic outlet syndrome (TOS). To date, no radiological study has been evaluated the prevalence of the SPM in the adult population. In this study, we aimed to assess the prevalence of the SPM using magnetic resonance imaging (MRI). METHODS: We retrospectively reviewed brachial plexus, neck, and thoracic MRI of the patients who underwent MRI for various pathologies. Only the patients whose MRI examinations did not have sufficient image quality and the patients who had any pathology that directly involved the thoracic outlet region were excluded from the study. The observers assessed images in the coronal plane to detect the presence of the SPM. The thickness of the muscle and the distance between the SPM and brachial plexus were also noted. RESULTS: MRI examinations of 350 patients, 174 males and 176 females, were evaluated. SPM was detected in 29 patients (8.3%). In 6 patients (1.7%), we identified bilateral SPM. The mean thickness of the muscle was 6.10 ± 1.60 mm (range 2.5-10 mm). In 21 sides (60%), the brachial plexus and SPM were touching each other. In the remaining 14 sides (40%), the mean distances between the SPM and brachial plexus were 2.32 ± 0.62 mm (range from 1.7 to 3.6 mm). CONCLUSIONS: We conducted the first radiological study that evaluated the prevalence of the SPM, and we also assessed the thickness of the SPM and the distance between the SPM and brachial plexus. We highlight that our study might be accounted as a first step for future studies to assess the role of the SPM in TOS.
Subject(s)
Muscle, Skeletal/abnormalities , Musculoskeletal Abnormalities/epidemiology , Thoracic Outlet Syndrome/etiology , Adult , Brachial Plexus/diagnostic imaging , Female , Humans , Magnetic Resonance Imaging , Male , Muscle, Skeletal/diagnostic imaging , Muscle, Skeletal/innervation , Musculoskeletal Abnormalities/complications , Musculoskeletal Abnormalities/diagnostic imaging , Neck/diagnostic imaging , Pectoralis Muscles , Prevalence , Retrospective StudiesABSTRACT
Patients with Klippel-Feil syndrome (KFS) have an increased incidence of vascular anomalies as well as vertebral artery (VA) anomalies. In this article, we presented imaging findings of a 15-year-old female patient with KFS with a rare association of extraforaminal cranially ascending right VA that originated from the ipsilateral carotid bulb. Trifurcation of the carotid bulb with VA is a very unusual variation and to the best of our knowledge, right-sided one has not been reported in the literature.
