Randall Peoples MD, Abstract Co-Author: Nothing to Disclose

Timothy Mueller, Abstract Co-Author: Nothing to Disclose

Thomas Perkins PhD, Abstract Co-Author: Employee, Koninklijke Philips Electronics NV

Janette Powell, Abstract Co-Author: Nothing to Disclose

Eric Hanson MD, Abstract Co-Author: Nothing to Disclose

William Werner Orrison MD, Presenter: Nothing to Disclose

Travis Snyder, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

Whole spine MRI of contortionists was performed in normal and extreme positions to examine anatomical changes that may result from extreme spinal motion. The range of spinal motion in this unique population was quantified.

Studies were performed with IRB approval, informed consent and were HIPAA compliant. The study included five female contortionists aged 20 to 49 years. Imaging was performed using open 1.0 Tesla (1T) and cylindrical 3.0 Tesla (3T) high field MRI systems. Data were viewed and analyzed with digital imaging and communications in medicine (DICOM) compliant tools.

Observation of the spine using real time and standard MRI methods allowed for the quantification of “normal” range of motion for this unique patient population relative to the general population. The total vertebral extension angle for C3 – L5 was found to be –188 degrees. The primary levels of stress during extension included the mid-cervical, thoracic-lumbar junction, and the lower lumbar spine. Posterior disc disease was consistently identified in the mid cervical and the lower lumbar levels. Four anterosuperior limbus vertebrae were identified in three individuals at the lower thoracic/upper lumbar levels and appear to represent avulsion injuries secondary to extreme spinal extension. The primary stress during flexion involved the hips, with minimal spinal vertebral flexion of approximately 50 degrees. This results in a difference in the extension/flexion angles of the spine in this group of extreme athletes being 238 degrees.

Whole Spine MRI was found to be a valuable tool in the evaluation of the baseline range of motion in contortionists. Spinal anatomy and pathology was successfully visualized on an open 1T MRI system using real time imaging during active contortion.

This study has shown that anterior limbus vertebrae possibly represent centrally located avulsion fractures of the anterosuperior vertebral endplates related to extreme spinal extension.

Peoples, R, Mueller, T, Perkins, T, Powell, J, Hanson, E, Orrison, W, Snyder, T, et al, , et al, , Full Range of Motion Whole Spine MRI Study of Contortionists: Anatomy and Pathology.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5007315.html