OBJECTIVETo investigate the effect of alendronate on the prevention and treatment of aseptic loosening of prosthesis.

METHODSA rat model of particle-induced osteolysis was used. Thirty-xis SD rats were divided into three groups: negative control group, positive control group and experiment group. Alendronate was administered by ig in experiment group. Positive control group and experiment group received intro-articular injections of ultrahigh molecular weight polyethylene (UHMWPE) particles at 4, 6, 8, 10 weeks postoperatively. Negative control group was received injection with mixture solution of mouse serum and PBS only. All animals were sacrificed at 12 weeks after operation for histologic examination. In vitro human peripheral blood mononuclear (PBMC)were separated and cultured and divided into five groups as group A: PBMC group, group B: PBMC and particles,group C:PBMC and particles with 10(-4) mol/L alendronate, group D:PBMC and particles with 10(-5) mol/L alendronate, group E: PBMC and particles with 10(-6) mol/L alendronate. The production of IL-1beta, IL-6, TNF-alpha in each group were tested.

RESULTSAlendronate could prevent particle-induced osteolysis. The production of IL-1beta, IL-6, TNF-alpha was inhibited when alendronate was used.

CONCLUSIONAlendronate can inhibit bone absorptive factors expression induced by wear particles and may be used in the prevention and treatment of aseptic loosening of prosthesis.