Prediction of Tibial Nonunion at the 6-week Time Point

Injury. 2018 Nov;49(11):2075-2082. doi: 10.1016/j.injury.2018.07.033. Epub 2018 Jul 29.


Introduction: Intramedullary (IM) nail fixation is a common operative treatment, yet concerns regarding the frequency of complications, such as nonunion, remain. Treatment of tibial shaft fractures remains a challenge, and little evidence of prognostic factors that increase risk of nonunion is available. The aim of this study was to develop a predictive model of tibial shaft fracture nonunion 6 weeks after reamed intramedullary (IM) nail fixation based on commonly collected clinical variables and the radiographic union score for tibial fractures (RUST).

Methods: A retrospective case-control study was conducted. All tibial shaft fractures treated at our level I trauma center from 2007 to 2014 were retrospectively reviewed. Only patients with follow-up until fracture healing or secondary operation for nonunion were included. Fracture gaps ≥3 mm were excluded. A total of 323 patients were included for study.

Results: Infection within 6 weeks of operation, standard RUST, and the Nonunion Risk Determination (NURD) score had statistically significant associations with nonunion (odds ratio > or < 1.0; p < 0.01). The NURD score was increasingly predictive of nonunion with decreasing RUST. All patients in the high RUST group (RUST ≥ 10), achieved union regardless of NURD score. In the medium RUST group (RUST 6-9), 25% of patients with a NURD score ≥7 experienced nonunion. In the low RUST group (RUST <6 or infection within 6 weeks), 69% of patients with a NURD score ≥7 experienced nonunion.

Conclusion: Three variables predicted nonunion. Based on these variables, we created a clinical prediction tool of nonunion that could aid in clinical decision making and discussing prognosis with patients.

Keywords: Intramedullary nail; Nonunion; Prediction model; Tibia; Tibial fracture.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Case-Control Studies
  • Female
  • Fracture Fixation, Intramedullary / adverse effects*
  • Fracture Fixation, Intramedullary / instrumentation
  • Fracture Healing / physiology*
  • Fractures, Ununited / diagnostic imaging
  • Fractures, Ununited / physiopathology*
  • Fractures, Ununited / surgery
  • Humans
  • Male
  • Middle Aged
  • Postoperative Complications / diagnostic imaging
  • Postoperative Complications / physiopathology*
  • Postoperative Complications / surgery
  • Predictive Value of Tests
  • Retrospective Studies
  • Risk Factors
  • Tibial Fractures / diagnostic imaging
  • Tibial Fractures / physiopathology
  • Tibial Fractures / surgery*
  • Time Factors
  • Treatment Outcome
  • Young Adult