The impact of radiographic parameters and bone grafting at the docking site on union following bone transport for segmental bone defects of the tibia and the femur: A retrospective cohort pilot study

Abstract

Context: In patients with large bone defects, the method of bone transport remains one of the most adopted surgical techniques. Nonunion at the docking site is a critical complication of bone transport procedures. Aims: This study aimed to explore the impact of bone grafting at the docking site as well as radiographic parameters on union rates in patients who underwent bone transport for segmental bone defects of the tibia or femur. Settings and Design: This is a retrospective cohort of a consecutive series of adult patients treated with bone transport by a single surgeon at a single academic medical center. Subjects and Methods: Baseline characteristics of patients, bone transport procedure data, radiographic alignment data, and outcomes of those with bone grafting at the docking site were compared to those that did not. Statistical Analysis Used: Wilcoxon–Mann–Whitney U and Fisher's exact tests were used to analyze the study's data. Results: Thirty-two patients were included. Ten of 11 patients with bone graft at the docking site achieved union. Fifteen of 21 patients with no graft achieved union. Of the group that underwent bone transport without grafting, better alignment in the sagittal plane was significantly associated with achieving union (P = 0.026). The distraction gap of those that went on to unite (m = 9.33) was smaller than those that developed nonunion (m = 15.17) (P = 0.051). Conclusion: Although statistically insignificant, grafting of the docking site seemed to decrease the occurrence of nonunion at the clinical level. Higher distraction gap and translation in the sagittal plane may be the best predictors for nonunion of the docking site among nongrafted patients.