The Role of Circular Frames in the Management of Tibial Fractures.

ABSTRACT

Introduction The purpose of this study is to evaluate the factors that impact the clinical and radiographic outcomes in a patient cohort undergoing external fixation for tibial fractures. We also aim to investigate the use of autograft, allograft, and synthetic bone graft in varying combinations in the setting of tibial bone loss with respect to optimal times to union. Methods This was a retrospective study, including 46 patients treated with a circular external fixator for the management of acute tibial fractures. The study was carried out over a 10-year period, between 2007 and 2017, at our institution. The mean follow-up at the time of review was 4.6 years. Primary outcome measures were 'time to union,' 'delayed union' (> 6 months), 'infection,' and 'duration of external fixation.' Secondary outcomes included 'length of hospital stay' and functional scores using the 'Short Form-12 (SF-12).' The statistical analysis included both univariate and multivariate analyses to control for confounding variables when assessing predictors of delayed union and infection. Results Forty-six patients fulfilled the study criteria. Fifteen fractures were classified as open. The mean number of procedures per patient was 3.8 and the mean length of stay per patient was 33 days. The mean time to union was 8.6 months overall. Significant predictors of prolonged time to union were the 'number of interventions' (p<0.01) the patient underwent and the 'bone graft type' (p<0.01) used. The time to union in the presence of either autograft or allograft was lengthened by the addition of synthetic graft. Five patients developed a deep tissue infection. The use of synthetic bone graft was significantly associated with infection (p<0.05). On subgroup analysis, it was found that the use of synthetic graft in any combination leads to significantly higher rates of deep tissue infection (p<0.05). The mean time to full weight bearing was 10.6 months (s=9.78, 3-36). The majority (57%) were using walking aids and 67% reported that the injury was still affecting their lifestyle. Conclusion Tibial fractures with bone loss are a complex group of injuries that often require multiple surgical interventions, prolonged hospital inpatient stay, and suboptimal functional outcomes in many cases. The best times to union are achieved when autograft is used alone without any other combination of bone graft type. The use of synthetic bone graft also significantly increases the rate of deep tissue infection in this cohort. We recommend the use of autograft alone when treating bone defects in tibial fractures with external fixators.