title: Predictors of the outcome of lumbar disc herniation following classical surgery : Laminotomy with discectomy.
abstract: BACKGROUND
  Several surgical variables and patient characteristics play an influential role in the prognosis of lumbar disc herniation following laminotomy with discectomy. This paper seeks to evaluate the perioperative predictor variables for the outcome of lumbar disc herniation.
  
  
  METHODS
  From October 2013 to July 2016, 166 surgical patients were evaluated using prospectively collected data. Patients' preoperative independent variables (age, sex, body mass index, level of disc herniation, pain duration, and American Society of Anesthesiologists Physical Score) were correlated with functional outcome measures such as primary outcome measures (length of hospital stay; postoperative visual analog scale, VAS; Oswestry disability index, ODI) and secondary outcome measures (operation room time; estimated intraoperative blood loss, EBL; complications; readmission) as dependent variables. Multivariate linear regression as well as independent and paired sample t‑tests were used to analyze data. Data processing and analysis were carried out in SPSS 16.0. Results were deemed significant at P < 0.05.
  
  
  RESULTS
  There were significant improvements in the postoperative mean VAS back and leg scores and the postoperative mean ODI back and leg scores compared to preoperative values. Using multivariate linear regression analysis, the association of patient age (b = 0.246, P = 0.003) and pain duration (b = 0.152, P = 0.04) with estimated intraoperative blood loss was statistically significant. Age was also associated with the postoperative VAS back score (b = -0.197, P = 0.02).
  
  
  CONCLUSIONS
  Pain duration and age are predictive of estimated blood loss. Patient age is also predictive of the postoperative VAS back score.
authors.affiliation: Department of Orthopedics, Affiliated Hospital of Jiangsu University, No. 438 Jiefang Road, 212001, Zhenjiang, Jiangsu, China. augbalaara@hotmail.com.
authors.forename: Augustine
authors.initials: A
authors.lastname: Balaara
authors.affiliation: Department of Orthopedics, Affiliated Hospital of Jiangsu University, No. 438 Jiefang Road, 212001, Zhenjiang, Jiangsu, China.
authors.forename: Xiao-Feng
authors.initials: XF
authors.lastname: Xu
authors.affiliation: Department of Orthopedics, Affiliated Hospital of Jiangsu University, No. 438 Jiefang Road, 212001, Zhenjiang, Jiangsu, China.
authors.forename: Young-Hui
authors.initials: YH
authors.lastname: Huang
authors.affiliation: Department of Orthopedics, Affiliated Hospital of Jiangsu University, No. 438 Jiefang Road, 212001, Zhenjiang, Jiangsu, China.
authors.forename: Li
authors.initials: L
authors.lastname: Dapeng
mesh_terms: D000328:Adult; D000368:Aged; D017586:Diskectomy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000175:diagnosis / Q000601:surgery*; D007796:Laminectomy; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009460:Neurologic Examination; D010043:Outcome and Process Assessment, Health Care; D017060:Patient Satisfaction; D011183:Postoperative Complications / Q000175:diagnosis / Q000209:etiology; D011379:Prognosis; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D064232:Visual Analog Scale
keywords: Age; Back pain; Lumbar disc herniation radiculopathy; Surgical blood losses; Visual analog scale