Treatment of large femoral and tibial bone defects with Plate-assisted Bone Segment Transport (PABST)

Abstract

OBJECTIVES: The purposes of this study were to assess clinical and radiographic outcomes following Plate-assisted Bone Segment Transport (PABST) in large bone defects of the lower extremities. METHODS: Design: Retrospective study of prospectively collected data. Setting: Level-1 trauma center located in Germany. Patient Selection Criteria: Patients who underwent PABST and were at least one year postoperatively were included. Outcome Measures and Comparisons: Demographic data were collected. Radiographic apparent bone gap (RABG), time to consolidation, as well as time to full weight bearing and consolidation index were calculated. Numeric Rating Scale (NRS), Lower Extremity Functional Scale (LEFS), and complications were assessed. RESULTS: Fifteen patients (13 male; mean age 51 years [range, 20-75]) underwent PABST and had follow-up at a mean of 29.1 months. The tibia was affected in 8 and the femur in 7 patients. Preoperative RABG was 60 mm (IQR: 40-125) and bone defects were caused by septic non-unions in 73%. Fourteen patients (93%) demonstrated consolidated transport callus at 7.3 months (95%CI: 6-8.5) and nine patients (60%) demonstrated complete consolidation of both docking site and transport callus at 11.5 months (95%CI: 7.3-15.3). Postoperative RABG was 0.1mm (IQR: 0-0.8), consolidation index was 1.9 months/cm (95%CI: 1.3-2.5). All patients achieved full weight-bearing at 8.7 months (IQR:6.5-10.3). LEFS was 42 (95%CI: 34-50) and NRS was 3 (95%CI: 2-4). Patients treated for tibial defects had a significantly higher consolidation rate compared to patients treated for femoral defects (p=.040). CONCLUSIONS: PABST demonstrated high consolidation of transport callus with few complications. Although full weight-bearing was achieved in all patients, complete consolidation of the docking site was only present in 60% of cases. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.