title: Pre- and postoperative correlation of patient-reported outcome measures with standardized Timed Up and Go (TUG) test results in lumbar degenerative disc disease.
abstract: The Timed Up and Go (TUG) test is a reliable tool for evaluating objective functional impairment (OFI) in patients with degenerative disc disease before a surgical intervention. The aim of this study is to assess the validity of the TUG test to measure change in function postoperatively.
  
  
  
  In a prospective two-center study, OFI was assessed by the TUG test in patients scheduled for lumbar spine surgery, as well as 3 days (D3) and 6 weeks (W6) postoperatively. At each time point, the TUG test results were correlated with established subjective measures of pain intensity (visual analogue scale (VAS) for back and leg pain), functional impairment (Oswestry Disability Index (ODI)) and health-related quality of life (HRQoL; Short Form-12 (SF12)).
  
  
  
  The patient cohort comprised 136 patients with a mean age of 57.7 years; 76 were males, 54 had a microdiscectomy for lumbar disc herniation, 58 a decompression for a lumbar spinal stenosis, 24 had a surgical fusion procedure. The mean OFI t-score was 125.1 before surgery, and as patients improved on the subjective measures in the postoperative interval, the OFI t-score likewise decreased to 118.8 (D3) and 103.4 (W6). The Pearson correlation coefficient (PCC) between the OFI t-score and VAS leg pain was 0.187 preoperatively (p = 0.029) and 0.252 at W6 (p = 0.003). The PCC between OFI t-score and the ODI was 0.324 preoperatively (p < 0.001) and 0.413 at W6 (p < 0.001). The PCC between OFI t-score and physical HRQoL (SF12) was -0.091 preoperatively (p = 0.293) and -0.330 at W6 (p < 0.001).
  
  
  
  The TUG test is sensitive to change, and reflects the postoperative functional outcome even more exact than preoperatively, as indicated by better correlation coefficients of the OFI t-score with subjective measures of pain intensity, functional impairment and HRQoL.
authors.affiliation: Department of Neurosurgery and Faculty of Medicine, University Hospital Geneva, Geneva, Switzerland. ogautschi@gmail.com.|Service de Neurochirurgie, Département des neurosciences cliniques, Hôpitaux Universitaires de Genève, Rue Gabrielle Perret-Gentil 4, 1205, Genève, Suisse. ogautschi@gmail.com.
authors.forename: Oliver P
authors.initials: OP
authors.lastname: Gautschi
authors.affiliation: Department of Neurosurgery, Cantonal Hospital St. Gallen, St. Gallen, Switzerland.
authors.forename: Holger
authors.initials: H
authors.lastname: Joswig
authors.affiliation: Department of Neurosurgery and Faculty of Medicine, University Hospital Geneva, Geneva, Switzerland.
authors.forename: Marco V
authors.initials: MV
authors.lastname: Corniola
authors.affiliation: Department of Neurology, John Hunter Hospital, Newcastle, Australia.
authors.forename: Nicolas R
authors.initials: NR
authors.lastname: Smoll
authors.affiliation: Department of Neurosurgery and Faculty of Medicine, University Hospital Geneva, Geneva, Switzerland.
authors.forename: Karl
authors.initials: K
authors.lastname: Schaller
authors.affiliation: Department of Neurology, John Hunter Hospital, Newcastle, Australia.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Hildebrandt
authors.affiliation: Department of Neurosurgery and Faculty of Medicine, University Hospital Geneva, Geneva, Switzerland.|Department of Neurology, John Hunter Hospital, Newcastle, Australia.
authors.forename: Martin N
authors.initials: MN
authors.lastname: Stienen
mesh_terms: D000328:Adult; D000368:Aged; D019299:Decompression, Surgical / Q000009:adverse effects*; D017586:Diskectomy / Q000009:adverse effects*; D005260:Female; D006801:Humans; D055959:Intervertebral Disc Degeneration / Q000601:surgery*; D008159:Lumbar Vertebrae / Q000601:surgery; D008297:Male; D008875:Middle Aged; D000071066:Patient Reported Outcome Measures; D011183:Postoperative Complications / Q000175:diagnosis* / Q000453:epidemiology; D011446:Prospective Studies; D011788:Quality of Life; D013130:Spinal Stenosis / Q000601:surgery*
keywords: Correlation; Degenerative disc disease; Lumbar spine surgery; Objective functional impairment; Objective outcome measurement; Postoperative outcome; Timed Up and Go test