Autologous mesenchymal stem cell (MSCs) transplantation for critical-sized bone defect following a wide excision of osteofibrous dysplasia

INTRODUCTION: Osteofibrous dysplasia is a rare non-neoplastic disease that is almost exclusive to pediatric tibial diaphysis. Wide excision of the lesion is recommended to avoid recurrence. However, such radical surgery will results in large segmental bone defects that will require further extensive reconstructive surgery. We report a novel approach of treating bone defect by implementing the diamond concept of bone healing using autologous bone marrow derived mesenchymal stem cells (BM-MSCs). PRESENTATION OF CASE: An eight-year-old Indonesian male presented with severe bowing deformity of the left lower leg. Radiographic and histological analysis confirmed the diagnosis of osteofibrous dysplasia. A wide excision of the defect was made leaving a critical-sized bone defect. A combination of autologous transplantation of 50 million BM-MSCs, hydroxyapatite (HA) granules, bone morphogenic protein 2 (BMP-2) and Djoko-Zarov hybrid circular external fixator was used to treat the defect. The outcomes measured were subjective complaints, functionality based on LEFS and radiological assessments. DISCUSSION: Radiographic assessments showed successful new bone tissue formation and integration of implanted HA granules. The external fixator was removed at 42 weeks after adequate callus formation and clinical stability was achieved. The patient underwent progressive functional improvements and reached a near normal functionality of 90% LEFS at 84 week. No therapy side effect or complication was reported. CONCLUSION: Osteofibrous dysplasia was successfully excised without signs of recurrence after 84-week follow-up. Autologous transplantation of augmented BM-MSCs has successfully created new normal bone tissue without causing any side effect and had significantly improved the patient’s quality of life.