title: Is the sedimentation sign associated with spinal stenosis surgical treatment effect in SPORT?
abstract: METHODS
  Subgroup analysis of the lumbar spinal stenosis (LSS) without degenerative spondylolisthesis diagnostic cohort of the Spine Patient Outcomes Research Trial multicenter randomized clinical trial with a concurrent observational cohort.
  
  
  OBJECTIVE
  To determine if sedimentation sign on magnetic resonance image can help with LSS treatment decisions.
  
  
  BACKGROUND
  LSS is one of the most common reasons for surgery in the US elderly, but there is a dearth of reliable diagnostic tools that give a clear indication for surgery. Recent studies have suggested that positive sedimentation sign on magnetic resonance image may be a possible prognostic indicator.
  
  
  METHODS
  All patients with LSS in both the randomized and observational cohorts had imaging-confirmed stenosis, were surgical candidates, and had neurogenic claudication for at least 12 weeks prior to enrollment. Patients were categorized as "mild," "moderate," or "severe" according to stenosis severity. Of the 654 patients with LSS enrolled in Spine Patient Outcomes Research Trial, complete T2-weighted axial and sagittal digitized images of 115 patients were available for retrospective review. An independent orthopedic spine surgeon evaluated these deidentified Digital Imaging and Communications in Medicine files for the sedimentation sign.
  
  
  RESULTS
  Sixty-six percent (76/115) of patients were found to have a positive sedimentation sign. Those with a positive sedimentation sign were more likely to have stenosis at L2-L3 (33% vs. 10% P=0.016) or L3-L4 76% vs. 51%, P=0.012), and to have severe (72% vs. 33%, P<0.0001) central stenosis (93% vs. 67% P<0.001) at 2 or more concurrent levels (57% vs. 18%, P=0.01). In multivariate models, the surgical treatment effect was significantly larger in the positive sedimentation sign group for Oswestry Disability Index (-16 vs. -7; P=0.02).
  
  
  CONCLUSIONS
  A positive sedimentation sign was associated with a small but significantly greater surgical treatment effect for Oswestry Disability Index in patients with symptomatic LSS, after adjusting for other demographic and imaging features. These findings suggest that positive sedimentation sign may potentially be a useful adjunct to help guide an informed treatment choice regarding surgery for LSS.
  
  
  METHODS
  2.
authors: *Department of Orthopaedics, Dartmouth-Hitchcock Medical Center, Lebanon, NH †The Dartmouth Institute for Health Policy and Clinical Practice, Geisel School of Medicine, Lebanon, NH ‡Institute for Evaluative Research in Orthopaedic Surgery, University of Bern, Bern, Switzerland §Centre for Health Sciences, Zurich University of Applied Sciences, Winterthur, Switzerland ¶Department of Orthopaedic Surgery, Asklepios Klinikum Uckermark, Schwedt, Germany; and ‖Department of Medicine, Geisel School of Medicine, Lebanon, NH.
authors: Rachel A
authors: RA
authors: Moses
authors: Wenyan
authors: W
authors: Zhao
authors: Lukas P
authors: LP
authors: Staub
authors: Markus
authors: M
authors: Melloh
authors: Thomas
authors: T
authors: Barz
authors: Jon D
authors: JD
authors: Lurie
mesh_terms: D000368:Aged; D000066491:Clinical Decision-Making; D019299:Decompression, Surgical; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008159:Lumbar Vertebrae / Q000473:pathology* / Q000601:surgery; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D013130:Spinal Stenosis / Q000473:pathology* / Q000601:surgery