INDUCED HEALING OF ANEURYSMAL BONE-CYSTS BY DEMINERALIZED BONE PARTICLES - A REPORT OF 2 CASES

Two cases of induced healing of aneurysmal bone cyst (ABC) following i ntralesional implantation of a bone paste made of autogeneic bone marr ow and allogeneic bone powder are reported. The calcaneum in one case and the superior pubic ramus in the other were blown out by an ABC and would have required extensive surgery. Via a minimal exposure, the cy st was partially evacuated and filled with an admixture of a partially demineralized bone particles with bone marrow. Ossification of the pe ripheral shell was the first sign of healing and was observed within t he first 3 postoperative months. Successful healing was observed in bo th cases. The rationale underlying this intralesional treatment was th at the bone grafting material might reverse ABC expansion by promoting ossification through a bone induction mechanism. The concept of this treatment was to retain the ABC tissue, using its own intrinsic osteog enic potential to promote healing. By triggering intralesional new bon e formation, the bone paste represented an effective means to reverse the expanding phase of ABC. The particulated bone allograft was easy t o handle and to introduced in an irregular cavity. Moreover, as a comp lete cyst evacuation was not required, a minimal surgical approach cou ld be used so that the risks and morbidity associated with an extensiv e approach were reduced. Its use is of particular interest in poorly a ccessible areas like the pelvis and spine.