Tibial Malalignment is an Independent Predictor of Nonunion After Intramedullary Nailing of Tibial Shaft Fractures.

Objectives: This study aimed to assess the relationship between postoperative alignment and nonunion in patients with tibial shaft fractures treated with intramedullary nailing.

Methods: Design: Retrospective case-control study.

Setting: Single academic trauma center.

Patients selection criteria: Adult patients with closed or open tibial shaft fractures (42A-C) treated with intramedullary nailing from 2007 to 2018.

Outcomes measures and comparisons: Case patients with nonunion were compared to control patients with radiographic evidence of healing in terms of the postoperative tibial alignment measured in the coronal and sagittal planes.

Results: Of the 192 included patients (median age, 38 years; 76% male), 51 patients had a nonunion, and 141 patients had united fractures and served as the control group. A strong association between postoperative tibial malalignment in one plane and nonunion (odds ratio [OR], 3.0; 95% confidence interval [CI], 1.1 to 8.3; P = 0.03) was demonstrated. This association was even greater for malalignment in both coronal and sagittal planes (OR, 5.7; 95% CI, 2.1 to 16.1; P < 0.001) after controlling for confounders.

Conclusion: After controlling for confounding factors, postoperative malalignment in the coronal or sagittal plane was associated with significantly increased odds of tibial shaft nonunion after intramedullary nailing.

Level of evidence: Therapeutic, Level III. See Instructions for Authors for a complete description of levels of evidence.