Reconstruction of gap non-union tibia with composite use of extramedullary fixation and bone transport by monorail fixator: a prospective case series.

Abstract

Non-union is a complex, multifactorial orthopaedic problem that requires multiple treatment modalities for its management. It can result from infection, segmental bone loss, soft-tissue loss, and associated host factors. External fixators as management of gap non-union are bulky and give rise to a number of complications In our study, we have described a technique where we have used extramedullary fixation in the form of a tibial locking plate and transportation of part of the tibial bone after corticotomy by a monorail fixator. The procedure was done in two stages where internal and external fixation was done after creating a gap at the non-union site. The bone was transported after corticotomy and fixed to the internal fixation device in the second stage. The external fixator was removed in the second stage and the patient was then followed up till the bony union. The evaluation was done by functional and radiological assessment along with the complications noted with the described procedure. Ten patients were enrolled in the study with a mean age of 33 years. The mean age of the patients was 33.7 ± 11.32 years with a mean size of the defect was 4.8 ± 1.7 cm. At 30 weeks out of nine patients, three patients had excellent and six had good functional results on the Association of Surgeons for Application and Methodology of Ilizarov (ASAMI) scale. The composite Musculoskeletal Tumor Society (MSTS) score was 76.66 % at the end of 30 weeks of follow-up. The mean time of consolidation was 134.4 days, whereas the mean union time was 145 days from index surgery. Ankle stiffness was the most common complication affecting 50% of the patients. Following closely was pin tract infection, which was present in 40% of the patients. According to Paley's classification, there were 11 obstacles, two problems and none were true complications. The integrated fixation is both safe and effective and has the advantage of early removal of the external fixator and a low complication rate as compared to use of a bulky conventional fixator alone. Moreover, it gives protection to the regenerated bone for a long period. So, this technique can be recommended for the management of segmental tibial defects.