Fig. 1

Complications of bone and joint allograft (cases 23 and 38). In the patients with stage IIB fibrosarcoma of distal radius, stage IIB chondrosarcoma of proximal humerus was treated with allograft bone joint transplantation to repair bone defects. a1 Preoperative anteroposterior and lateral X-rays. a2–a4 Continuous follow-up of X-ray after surgery, the proximal part of the allograft gradually developed bone resorption leading to bone nonunion, and the distal carpal surface developed secondary osteoarthritis (white arrows indicate sites of nonunion and osteoarthritis, respectively). b1 Preoperative anteroposterior X-rays. b2–b4 The length of the allograft was 18 cm. Follow-up revealed that the allograft was gradually absorbed, with nonunion of the host–donor junction, loosening of the internal fixation, and eventually the allograft fracture occurred (black arrows indicate sites of bone resorption and fracture location, respectively)