[What's new in fundamental research: osteolysis and bone tumor].

Focal osteolysis is still an unresolved challenge for orthopaedic surgeon. Beside major advances in understanding mechanism of bone formation (namely BMP growth factors), recent identification of the major biological triade OPG: RANK: RANK-L and it's involvement in pathological osteolysis has opened new approaches for treatment of osteolysis associated to different conditions as particule-induced osteolysis around articular implants, bone tumor induced osteolysis. Better understanding of bone microenvironment and it's modulation could modify in the future surgical treatment of such conditions.