title: Risk factors for nonunion after intramedullary nailing of femoral shaft fractures: Remaining controversies.
abstract: BACKGROUND
  Intramedullary nailing (IMN) is the preferred treatment for femoral shaft fractures in adults. Although previous studies published good outcomes, some controversies remain. The purpose of this retrospective study was to identify factors that influence outcome after IMN for femoral shaft fractures.
  
  
  METHODS
  Between July 1998 and July 2013, we treated 230 patients with 248 femoral shaft fractures. Statistical analyses were performed to determine predictors of nonunion. The following set of variables was selected based on the speculation that they would contribute to the outcome: sex (male or female), smoking, obesity, polytrauma, fracture type, open fractures, Gustilo type, primary external fixation (EF) and reaming.
  
  
  RESULTS
  Initial fracture stabilization was performed by IMN in 161 (64.9%) and by EF in 87 (35.1%) fractures. There were no documented cases of deep infection. Nonunion was diagnosed in 27 patients with 28 fractures (11.3%). Factors affecting nonunion in the univariate analysis were Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association (AO/OTA) fracture type (odds ratio [OR] 25.0; p<0.0001), Gustilo type (OR 0.64; p=0.0358), and EF (OR 0.42; p=0.0401). Multiple logistic regression analysis only identified AO/OTA fracture type (OR 22.0; p<0.0001) as a risk factor for nonunion. Fracture reaming did not change the outcome (OR 0.80; p=0.6073). A separate analysis showed that damage control EF was not a risk factor in polytrauma patients (OR 0.76; p=0.5825).
  
  
  CONCLUSIONS
  Fracture stabilisation with IMN is a good treatment option for femoral shaft fractures in adults. The purpose of this study was to evaluate risk factors of poor outcome after IMN of femoral shaft fractures. The present analysis revealed that there was no difference in the outcome whether the fracture was reamed or not. Univariate and multivariate analysis could only correlate AO/OTA fracture type with the occurrence of nonunion. Therefore, in this study, unreamed nailing and damage control EF were not associated with a negative outcome.
authors.affiliation: Department of Trauma Surgery, University Hospitals Leuven, B-3000 Leuven, Belgium. Electronic address: wilhelmus.metsemakers@uzleuven.be.
authors.forename: W-J
authors.initials: WJ
authors.lastname: Metsemakers
authors.affiliation: Department of Trauma Surgery, University Hospitals Leuven, B-3000 Leuven, Belgium.
authors.forename: N
authors.initials: N
authors.lastname: Roels
authors.affiliation: KU Leuven - University of Leuven, L-BioStat, B-3000 Leuven, Belgium.
authors.forename: A
authors.initials: A
authors.lastname: Belmans
authors.affiliation: Department of Orthopaedic and Trauma Surgery, Brugmann University Hospital, B-1000 Brussels, Belgium.
authors.forename: P
authors.initials: P
authors.lastname: Reynders
authors.affiliation: Department Development and Regeneration, KU Leuven - University of Leuven, B-3000 Leuven, Belgium; Department of Trauma Surgery, University Hospitals Leuven, B-3000 Leuven, Belgium.
authors.forename: S
authors.initials: S
authors.lastname: Nijs
mesh_terms: D000328:Adult; D005260:Female; D005264:Femoral Fractures / Q000150:complications / Q000601:surgery*; D005594:Fracture Fixation, Intramedullary / Q000009:adverse effects / Q000379:methods*; D017102:Fracture Healing; D005599:Fractures, Ununited / Q000453:epidemiology / Q000517:prevention & control / Q000601:surgery*; D006801:Humans; D015601:Injury Severity Score; D007902:Length of Stay; D008297:Male; D017063:Outcome Assessment, Health Care; D011183:Postoperative Complications / Q000453:epidemiology / Q000517:prevention & control / Q000601:surgery*; D012189:Retrospective Studies; D012307:Risk Factors
keywords: Complications; Damage control external fixation; Femoral shaft fracture; Infection; Intramedullary nailing; Nonunion