Extreme bone lengthening by bone transport with a unifocal tibial corticotomy: a case report.

Background: Bone transport is used for the treatment of extensive limb bone defects. The application of ring or unilateral external fixators combined with single or double corticotomy are well documented; however, there are few cases adopting a single corticotomy to repair bone defects > 24 cm.

Case Presentation: The present case study describes an 18-year-old male, who was involved in a traffic accident and was diagnosed with open fracture of the right tibia. The patient received emergency surgery in a local hospital and was transferred to The Second People's Hospital of Yunnan for further treatment 3 months later. The patient was diagnosed with fracture nonunion and infection following admission. Complete debridement was performed three times to control the infection. The infection was resolved after 26 days and the 24.5 cm massive tibia defect remained the biggest challenge. The bone transport technique involving a unilateral external fixator and single corticotomy was employed to treat the bone defect. Docking site union was achieved and bone consolidation was complete 40 months after corticotomy. The external fixator was subsequently removed. The bone healing index was 1.6 months/cm. The Association for the Study and Application of the Method of Ilizarov criteria (ASAMI) revealed a good functional and bone repair result. Similarly, Knee Society Score (KSS) yielded good result and the The Lower Extremity Functional Scale (LEFS) was 65. A total of 45 months after injury, the patient was able to walk painlessly without ambulatory assistive devices and resumed daily activities successfully. Eighteen months after the bone and soft tissue wound have healed, the SF-36 score was 86, and the LEFS was 70.

Conclusion: To the best of the authors' knowledge, the present study described the longest bone defect repair performed using bone transport with single level corticotomy.