The Impact of Time to Surgical Debridement on Infection Rates in Open Tibial Shaft Fractures Treated with Immediate Medullary Nailing.

Objectives: To evaluate whether time to surgical debridement and medullary nailing of open tibial shaft fractures was predictive of infection.

Methods: Design: Retrospective chart review.

Setting: Single, academic, level-1 trauma center.

Patient selection criteria: All skeletally mature patients with open tibial shaft fractures (AO/OTA type 42) who presented to a level-1 trauma center between 2012 and 2024 with a minimum follow-up of 3-months were included. All patients underwent definitive treatment consisting of irrigation and debridement, followed by immediate intramedullary nailing during the same anesthetic. Patients with type IIIB fractures who did not receive soft tissue coverage within 7 days of presentation, as well as those with type IIIC fractures were excluded.

Outcome measures and comparisons: The primary outcome measure was the incidence of deep infection necessitating a return to the operating room. Time to surgery was evaluated as a secondary outcome. Time intervals to surgical debridement were categorized as follows: less than 6 hours, 6 to 12 hours, 12 to 18 hours, 18 to 24 hours, and greater than 24 hours. Multivariate binary logistic regression analyses were performed to determine whether key factors, including age, diabetes, fracture type, smoking, ASA classification, and time to debridement at the previously categorized time points were predictive of infection.

Results: A total of 393 patients (306 males) with a mean age of 38 years (range 15-87 years) were included. Of these, 24 patients (6%) had diabetes and 126 patients (32%) were smokers. There were 78 (20%) type I fractures, 170 (43%) type II fractures, and 144 (37%) type III fractures. Of the type III fractures, 99 (68%) were type IIIA while 45 (32%) were type IIIB. A total of 32 patients (8%) were treated within 6 hours, 111 patients (28%) between 6 and 12 hours, 131 patients (33%) between 12 and 18 hours, 69 patients (18%) between 18 and 24 hours, and 50 patients (13%) after 24 hours. A total of 46 infections (12.5%) were observed: 6 infections (13%) in type I fractures, 14 infections (20%) in type II fractures, 10 infections (22%) in type IIIA fractures, and 16 infections (35%) in type IIIB fractures. Time to surgery was not predictive of infection (p=0.31). Logistic regression analysis showed that patients with a type IIIB fracture were 6.1 times more likely to develop an infection compared to other fracture types (OR = 6.147, 95% CI: 1.975- 19.129, p = 0.002). Smokers were 2.8 times more likely to develop an infection (OR = 2.779, 95% CI: 1.357-5.691, P = 0.005). Age, time to debridement at the specified time points, diabetes, and ASA classification did not significantly predict infection (p = 0.32, 0.31, 0.27, and 0.50, respectively).

Conclusions: Smoking and type IIIB fractures were identified as significant predictors of infection following immediate medullary nailing of open tibial shaft fractures, whereas time to debridement, within the categorized time points, was not found to be a significant factor.