title: Effects of X-STOP device on sagittal lumbar spine kinematics in spinal stenosis.
abstract: The X-Stop device is designed to distract the posterior elements of the stenotic segment and place it in flexion to treat neurogenic claudication. Previous biomechanical studies on X Stop have been done in vitro on cadavers looking at disc pressures and segmental range of movements. The objective of this study is to understand the sagittal kinematics in vivo of the lumbar spine at the instrumented and adjacent levels. Twenty-six patients with lumbar spine stenosis underwent 1 or 2 level X-Stop procedure. All had pre- and postoperative positional magnetic resonance imaging (MRI) in standing, supine, and sitting in flexion and extension. Measurements of disc heights, endplate angles, segmental and lumbar range of movement were performed after placement of X Stop at the stenosed level in patients with lumbar spinal stenosis. No significant changes were seen in disc heights, segmental and total lumbar spine movements postoperatively. The X-Stop device does not affect the sagittal kinematics of the lumbar spine in vivo.
authors.affiliation: Department of Orthopaedics, Woodend Hospital, Aberdeen, Scotland. manalsiddiquis@yahoo.co.uk
authors.forename: Manal
authors.initials: M
authors.lastname: Siddiqui
authors.forename: Efthimios
authors.initials: E
authors.lastname: Karadimas
authors.forename: Malcolm
authors.initials: M
authors.lastname: Nicol
authors.forename: Francis W
authors.initials: FW
authors.lastname: Smith
authors.forename: Douglas
authors.initials: D
authors.lastname: Wardlaw
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena / Q000379:methods; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000000981:diagnostic imaging / Q000502:physiology / Q000601:surgery*; D007595:Joint Prosthesis; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000502:physiology / Q000601:surgery*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011859:Radiography; D013130:Spinal Stenosis / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*