RT Journal Article SR Electronic T1 FM1-7 Cranio-cervical instability in ehlers-danlos syndrome employing upright, dynamic MR imaging; a comparative study JF Journal of Neurology, Neurosurgery & Psychiatry JO J Neurol Neurosurg Psychiatry FD BMJ Publishing Group Ltd SP e22 OP e22 DO 10.1136/jnnp-2019-ABN.69 VO 90 IS 3 A1 GK Prezerakos A1 F Khan A1 I Davagnanam A1 F Smith A1 AT Casey YR 2019 UL http://jnnp.bmj.com/content/90/3/e22.2.abstract AB Objectives Ehlers-Danlos syndrome (EDS) is a hereditary connective tissue disorder leading to hypemobile joints including the craniocervical junction. Neck pain is a prominent feature. Structural abnormalities may have a dynamic element and thus may not be captured in a recumbent MRI. There is currently a lack of evidence1 assessing the use and diagnostic impact of positional MRI in Ehlers-Danlos syndrome. We aim to evaluate structural features and dynamic instability in an EDS cohort employing dynamic MR imaging against a non EDS symptomatic cohort.Design Comparative Study.Subjects Patients diagnosed with Ehlers-Danlos syndrome and control subjects (non EDS with cervical spondylosis) were included in this study.Methods Cranio – cervical spine global and segmental movement parameters in the neutral, extension and flexion positions were measured from T2-weighted images in the midline sagittal plane. These parameters included the clivo axial angle, grabb oakes line, C2 sagittal vertical axis, C0-C1 angle, C1-2 angle, cervical lordosis and T1 slope.Results The clivo- axial angle measured in neutral was 139.7±10.4 degrees in the EDS group vs 148.9±8.4 in the control group (p<0.01) The cervical range of movement between flexion and extension was 74.6±24.4 in the EDS group vs 39.4±11.3 in the controls (p<0.0001).Conclusions EDS patients with neck symptoms exhibit different static as well as dynamic craniocervical structural features compared to a general population control.ReferenceOnt Health Technol Assess Ser [Internet]2015July;15(13):1–24.