title: Impact of smoking and preoperative electrophysiology on outcome after open carpal tunnel release.
abstract: BACKGROUND
  The aim was to evaluate the influence of smoking and preoperative electrophysiology on the outcome of open carpal tunnel release.
  
  
  METHODS
  This retrospective observational study evaluated the outcome in 493 patients (531 hands) primary operated for carpal tunnel syndrome. Data were collected from medical records, health evaluations, and QuickDASH questionnaires before surgery and 1 year after.
  
  
  RESULTS
  Smokers had a higher QuickDASH score preoperatively as well as postoperatively, but the change in total score did not differ. The odds of having a postoperative QuickDASH score >10 were 2.5 times higher in smoking patients than in non-smoking patients. In 124/493 patients (25%), no clinically significant improvement was seen. Normal and extreme preoperative electrophysiology values were associated with higher postoperative scores. No correlation was found between preoperative QuickDASH scores and preoperative electrophysiology values.
  
  
  CONCLUSIONS
  Smokers with carpal tunnel syndrome experience more symptoms preoperatively. Smokers have remaining symptoms after surgery. There is no correlation between preoperative QuickDASH scores and preoperative electrophysiology values. Patients with normal or near to normal preoperative electrophysiology results have limited improvement after surgery.
authors.affiliation: a Department of Hand Surgery , Lund University, Skåne University Hospital , Malmö , Sweden.
authors.forename: Erik
authors.identifier: http://orcid.org/0000-0003-0326-3060
authors.initials: E
authors.lastname: Dahlin
authors.affiliation: a Department of Hand Surgery , Lund University, Skåne University Hospital , Malmö , Sweden.
authors.forename: Malin
authors.identifier: http://orcid.org/0000-0002-9925-3838
authors.initials: M
authors.lastname: Zimmerman
authors.affiliation: a Department of Hand Surgery , Lund University, Skåne University Hospital , Malmö , Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Björkman
authors.affiliation: a Department of Hand Surgery , Lund University, Skåne University Hospital , Malmö , Sweden.
authors.forename: Niels O B
authors.initials: NOB
authors.lastname: Thomsen
authors.affiliation: b Department of Clinical Sciences Lund, Clinical Neurophysiology , Lund University and Skåne University Hospital , Sweden.
authors.forename: Gert S
authors.initials: GS
authors.lastname: Andersson
authors.affiliation: a Department of Hand Surgery , Lund University, Skåne University Hospital , Malmö , Sweden.|c Department of Translational Medicine-Hand Surgery , Lund University , Malmö , Sweden.
authors.forename: Lars B
authors.identifier: http://orcid.org/0000-0003-1334-3099
authors.initials: LB
authors.lastname: Dahlin
mesh_terms: D000328:Adult; D000368:Aged; D002349:Carpal Tunnel Syndrome / Q000000981:diagnostic imaging / Q000601:surgery*; D015331:Cohort Studies; D016208:Databases, Factual; D019299:Decompression, Surgical / Q000009:adverse effects / Q000379:methods*; D004576:Electromyography / Q000379:methods*; D004594:Electrophysiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology / Q000503:physiopathology; D011300:Preoperative Care / Q000379:methods; D020127:Recovery of Function / Q000502:physiology*; D012016:Reference Values; D012189:Retrospective Studies; D012720:Severity of Illness Index; D012907:Smoking / Q000009:adverse effects*; D016896:Treatment Outcome
keywords: Carpal tunnel syndrome; carpal tunnel release; electrophysiology; smoking