Pelvic reconstruction using massive frozen autograft bearing tumor

Abstract

9040 Background: Allograft is difficult to obtain in Japan for socioreligious reasons, so autograft bone, such as irradiation, autoclaving and pasteurization et al, has been widely used. However, they may cause weakness of the treated bone and loss of bone induction activity. So we developed a new method for treating autografts that utilizes the hypothermic effect of liquid nitrogen, especially reconstruction after the resection of illiosacral joint or periacetabulum, based on the results of in vitro and in vivo studies. Methods: Six patients with pelvic malignant bone tumors (2 chondrosarcomas, 1 osteosarcoma, 1 Ewing sarcoma and 2 metastatic tumors) were treated with this method. All these tumors invaded illiosacral joint or periacetabulum, the type of resection were P14P4, P14, P123, P124, P2and P12P12 according to Enneking's classification. After tumor excision, the tumor and surrounding soft tissue were removed, and the specimen was immediately frozen in liquid nitrogen for 20 minutes. Later, the specimen was gradually thawed at room temperature and in distilled water. Finally reconstructed with liquid nitrogen autograft, osteosynthesis with suitable internal fixation. Results: With a mean follow-up of 18 months, union of host-graft junction was observed in 6 patients in 5.5 months after surgery, and the reconstruction of pelvic ring was complete in 5 patients. Osteoarticular reconstruction was performed perfectly for 6 patients. Excellent function was found in 3 patients, good in one, fair in one and poor in one. As for complications, there were two deep infections, frozen autograft was removed in one patient, the other patient was given debridement and the infection subsided eventually. Bone absorption and fracture were not found. One local recurrence arised from residual soft tissue. Three patients were still free of disease and three had died of metastatic disease. Conclusions: This biological reconstruction is considered to be a new and promising option in pelvic and sacral tumor, because it can provide perfect matching and immediate stability. No significant financial relationships to disclose.