Session X1 - Tibia
Factors Affecting Union following Severe Open Tibia Fractures (OTA Types 42A, B, C): A Prospective, Multi-center Study
Purpose: This study was conducted to determine what patient demographic factors, injury characteristics, and surgical strategies are associated with the development of a nonunion following a severe open tibia-fibula shaft fracture.
Background: Accurate prediction of the likelihood of developing a tibial nonunion following a significant open tibia fracture may facilitate earlier treatment of patients at risk.
Methods: Between July 2000 and September 2004, patients with Gustilo II-IIIA tibia fractures were enrolled at 32 sites in a prospective protocol for management of their open tibia fractures. All underwent a similar operative protocolreamed, locked intramedullary nailing of the fracture and irrigation debridement of their open wounds, with randomization to delayed or immediate wound closure. Patients were followed by their treating surgeons at standard intervals. Radiographs were obtained to assess fracture union. Bridging on æ cortices and painless ambulation were considered clinical evidence of fracture union. Patients whose fractures had not healed by 6 months or who had undergone surgery for nonunion prior to 6 months were considered to have a nonunion. Potential predictors of nonunion were analyzed individually and in adjusted models.
Results: A total of 466 patients were enrolled in the study. Of these, 399 (86%) had completed at least 12 months follow-up and were available for this study. The sample was 66% male, with average age 37 years (range, 17 to 82). Motor vehicle accidents (74%) and falls (11%) were the most common injury mechanisms. Fracture patterns were 37% 42A, 26% 42B, and 32% 42C (5% missing). 193 patients (41%) were current smokers, and 16 (3%) had diabetes. 264 patients (66%) were reported healed by 6 months, and 44 patients (11%) underwent surgery to obtain union prior to 6 months. Factors that were associated with the development of a nonunion included tobacco use (P=0.03) and pedestrian struck mechanism of injury (P=0.05).
Discussion: When treating patients with severe open tibia fractures, it is important to identify those injuries that may require further surgical intervention. We have identified tobacco use and mechanism of injury as potential risk factors for developing a nonunion that may require a secondary surgical intervention to obtain maximal functional outcome. Also noteworthy was the apparent lack of difference in outcomes by timing of wound closure. This information is important so that physicians treating these injuries can counsel patients regarding expected outcomes.