Figure 7: Histology of the harvested femur at 12 weeks postoperatively. Single and double arrows indicate grafted bone (irradiated bone) and the host femur, respectively. Asterisks indicate newly formed bone. (a), (b), (c), and (d) Sheet group; (e), (f), (g), and (h) control group. (a) and (e) von Kossa staining; (b), (c), (f), and (g) Villanueva-Goldner staining. (a) New bone formation was observed around the grafted bone. (b) New bone formation was also observed around the grafted bone. (c) Higher-magnification image of the rectangular area in (b). Grafted bone and the host femur were united by newly formed bone (asterisks). (d) Diagram of (a) and (b). (e) No bone formation was observed around the grafted bone. (f) Bone formation was also not observed around the grafted bone. (g) Higher-magnification image of the rectangular area in (f). Fibrous tissue was observed between the grafted bone and host femur, indicating nonunion. (h) Diagram of (e) and (f).