Fig. 6A–H.

Representative longitudinal histology sections of fusion mass of each group at 4 weeks after surgery are shown. (A and E) BMP5; (B and F) BMP15: (C and G) BMP50; (D and H) BMP150. (Stain, TRAP; original magnification, A–D: x100, E–H: ×400). Right panels show higher magnifications of each left panel. E-BMP-2 treatment could histologically achieve remodeling of newly formed fusion mass as same as autogenous bone graft. TRAP-positive giant cells, that are osteoclasts, are abundant in the BMP50 and BMP150 groups.