Hexapod Stacked Transport for Tibial Infected Nonunions With Bone Loss: Long-Term Functional Outcomes.

Abstract

To analyze long-term functional outcomes in patients with posttraumatic infected tibial nonunions having undergone bone transport with hexapod external fixator. Retrospective cohort study. Level 1 trauma center. Thirty-eight patients with infected nonunions of the tibia. Resection of nonunion with application of stacked hexapod external fixator for bone transport. Functional outcome was measured using the short Musculoskeletal Functional Assessment (sMFA). Parameters measured included age, sex, presence of diabetes, smoking, use of a free flap, bone defect size, length in frame, external fixation index, and direction of lengthening. The mean sMFA score for the entire group was 27.1. Average patient age was 46.8 ± 12.7 years, 74% patients were male, 8% were diabetic, and 29% were smokers. Seventeen patients had soft-tissue defects that required a free flap. Smokers had higher degrees of disability compared with nonsmokers (39 ± 16 vs. 22 ± 14, P = 0.011). Patients requiring adjunctive stabilization had worse functional scores compared with those who did not receive adjunctive stabilization (33 ± 17 vs. 22 ± 15, P = 0.049). Sixteen patients returned 2 sMFA surveys at different time points after completion of bone transport. Initial average sMFA score was 26.5 at a mean of 25.3 months; subsequent sMFA scores averaged 19.4 at a mean of 98.8 months. Stacked hexapod external fixator bone transport is a reliable technique for infected nonunion of the tibia with bone loss. Improved sMFA scores can be expected from 2 to 8 years, suggesting full recovery takes longer than previously anticipated. Limb salvage with hexapod bone transport is justified over time. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.