title: Lying Down Instability Undetected on Standing Dynamic Radiographs.
abstract: It is well known that spinal instability should be evaluated in the standing lateral position. Standing dynamic flexion and extension radiographs are usually used to assess spinal instability. Here, we report a patient who experienced distraction instability while in the supine position rather than the standard standing position. To our knowledge, this is the first report of lying-down instability undetected on standing dynamic flexion and extension radiographs. We discuss the pathophysiological mechanism of this uncommon but possible entity and provide a review of the literature.
authors.affiliation: Department of Neurosurgery, Heori Sarang Hospital, Daejeon, Korea.
authors.forename: Hyeun Sung
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Department of Neurosurgery, College of Medicine, Chosun University, Gwangju, Korea.
authors.forename: Chang Il
authors.initials: CI
authors.lastname: Ju
authors.affiliation: Department of Neurosurgery, College of Medicine, Chosun University, Gwangju, Korea.
authors.forename: Seok Won
authors.initials: SW
authors.lastname: Kim
authors.affiliation: Department of Rehabilitation, College of Medicine, Chosun University, Gwangju, Korea.
authors.forename: Jung Hoon
authors.initials: JH
authors.lastname: Kang
keywords: Distraction; Dynamic; Instability
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