title: Outcome after surgical treatment for lumbar spinal stenosis: the lumbar extension test is not a predictive factor.
abstract: METHODS
  A prospective clinical study.
  
  
  OBJECTIVE
  To investigate the predictive value of the lumbar extension test for outcome after surgical treatment of lumbar spinal stenosis (LSS).
  
  
  BACKGROUND
  Studies have indicated that aggravation of the symptoms from LSS by extension of the lumbar spine has predictive value for the outcome after decompression. The aim of this study was to investigate this theory in a larger group of patients.
  
  
  METHODS
  One hundred forty-six consecutive patients surgically treated for LSS were included in the study. The clinical condition was recorded before surgery and at 3, 6, 12, and 24 months after surgery using 3 different scoring systems: Swiss Spinal Stenosis Questionnaire, Neurogenic Claudication Outcome Score, and Oswestry Disability Index. The group of patients with preoperative aggravation of the symptoms by the lumbar extension test, (positive extension test), was compared with the group of patients without aggravation by the test, (negative extension test).
  
  
  RESULTS
  Before surgery, patients with a positive extension test scored significantly worse on all disability scoring systems than patients with a negative test. However, the extension test itself had no prognostic value for the overall outcome after lumbar decompression. Using regression models with the 2-year Oswestry Disability Index as dependent variable, only before surgery self-reported health and age were found to have prognostic significance.
  
  
  CONCLUSIONS
  The lumbar extension test has no predictive value for the outcome after surgical treatment of LSS.
authors: Neuroscience Center, University Clinic of Neurosurgery, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark.
authors: Lars
authors: L
authors: Westergaard
authors: John
authors: J
authors: Hauerberg
authors: Jacob B
authors: JB
authors: Springborg
mesh_terms: D000368:Aged; D004185:Disability Evaluation; D005260:Female; D005500:Follow-Up Studies; D006306:Health Surveys; D006801:Humans; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D017063:Outcome Assessment, Health Care / Q000592:standards*; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D012044:Regression Analysis; D013130:Spinal Stenosis / Q000175:diagnosis* / Q000601:surgery*; D016896:Treatment Outcome