Demineralized bone implants for nonunion fractures, bone cysts, and fibrous lesions.

Demineralized bone implants were used to treat eight patients with fracture nonunion, five patients with bone cysts, and eight patients with fibrous lesions. Five of the eight patients with nonunions had had previous unsuccessful attempts at reconstruction. After fixation and implantation with either human or bovine demineralized bone, all eight fractures healed. For those patients with nonunion fractures, mean followup time was 8 years, 5 months, and longest followup was 15 years, 3 months. The cystic lesions in five patients included three typical aneurysmal bone cysts and two recurrent unicameral bone cysts. The aneurysmal bone cysts had excellent healing and bone remodeling. The two unicameral bone cysts were repacked more densely after 1 year and healed. For these patients with bone cysts, the mean followup time was 12 years, 5 months, and longest followup was 15 years, 1 month. The various fibrous lesions in seven of the eight patients were healed within 6 months, with only one requiring repacking. For these patients with fibrous bone lesions, the mean followup time was 9 years, 8 months, and longest followup was 14 years. A biopsy of the lesions in five patients was performed and in two cases showed osteoblasts and new bone around small particles of the implants. These results with long term followup show that allogeneic or xenogeneic demineralized bone implants offer a reasonable alternative for the treatment of typical nonunion fractures, bone cysts, and fibrous lesions of bone.