title: A valid model for predicting responsible nerve roots in lumbar degenerative disease with diagnostic doubt.
abstract: OBJECTIVE
  To construct and validate a model to predict responsible nerve roots in lumbar degenerative disease with diagnostic doubt (DD).
  
  
  METHODS
  From January 2009-January 2013, 163 patients with DD were assigned to the construction (n = 106) or validation sample (n = 57) according to different admission times to hospital. Outcome was assessed according to the Japanese Orthopedic Association (JOA) recovery rate as excellent, good, fair, and poor. The first two results were considered as effective clinical outcome (ECO). Baseline patient and clinical characteristics were considered as secondary variables. A multivariate logistic regression model was used to construct a model with the ECO as a dependent variable and other factors as explanatory variables. The odds ratios (ORs) of each risk factor were adjusted and transformed into a scoring system. Area under the curve (AUC) was calculated and validated in both internal and external samples. Moreover, calibration plot and predictive ability of this scoring system were also tested for further validation.
  
  
  RESULTS
  Patients with DD with ECOs in both construction and validation models were around 76 % (76.4 and 75.5 % respectively).
  
  
  METHODS
  more preoperative visual analog pain scale (VAS) score (OR = 1.56, p < 0.01), stenosis levels of L4/5 or L5/S1 (OR = 1.44, p = 0.04), stenosis locations with neuroforamen (OR = 1.95, p = 0.01), neurological deficit (OR = 1.62, p = 0.01), and more VAS improvement of selective nerve route block (SNRB) (OR = 3.42, p = 0.02).
  
  
  RESULTS
  the internal area under the curve (AUC) was 0.85, and the external AUC was 0.72, with a good calibration plot of prediction accuracy. Besides, the predictive ability of ECOs was not different from the actual results (p = 0.532).
  
  
  CONCLUSIONS
  We have constructed and validated a predictive model for confirming responsible nerve roots in patients with DD. The associated risk factors were preoperative VAS score, stenosis levels of L4/5 or L5/S1, stenosis locations with neuroforamen, neurological deficit, and VAS improvement of SNRB. A tool such as this is beneficial in the preoperative counseling of patients, shared surgical decision making, and ultimately improving safety in spine surgery.
authors.affiliation: Department of Orthopedic, Navy General Hospital, NO. 6 Fucheng Road, Beijing, 100048, China.|Department of Orthopedic, Gaozhou people's Hospital, Guangdong, China.
authors.forename: Xiaochuan
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Orthopedic, Navy General Hospital, NO. 6 Fucheng Road, Beijing, 100048, China.
authors.forename: Xuedong
authors.initials: X
authors.lastname: Bai
authors.affiliation: Department of Orthopedic, Navy General Hospital, NO. 6 Fucheng Road, Beijing, 100048, China.
authors.forename: Yaohong
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Department of Orthopedic, Navy General Hospital, NO. 6 Fucheng Road, Beijing, 100048, China. ruandike@163.com.
authors.forename: Dike
authors.initials: D
authors.lastname: Ruan
mesh_terms: D000368:Aged; D019540:Area Under Curve; D016009:Chi-Square Distribution; D002681:China; D003661:Decision Support Techniques; D005260:Female; D006801:Humans; D055959:Intervertebral Disc Degeneration / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery; D016015:Logistic Models; D008159:Lumbar Vertebrae / Q000503:physiopathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009407:Nerve Block / Q000379:methods; D016017:Odds Ratio; D010147:Pain Measurement; D018579:Patient Selection; D011237:Predictive Value of Tests; D012372:ROC Curve; D015203:Reproducibility of Results; D012307:Risk Factors; D013126:Spinal Nerve Roots / Q000503:physiopathology* / Q000601:surgery; D013130:Spinal Stenosis / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery
keywords: Diagnostic doubt; Lumbar degenerative disease; Predictive model; Selective nerve route block