|Ph.D Student||Fuchs Dror|
|Subject||Model of Rat Femoral Head Endoprostheses: Caracterization,|
Acceleration and Prevention of the Aseptic
|Department||Department of Medicine||Supervisors||Assistant Professor Dina Lewinson|
|Professor Raymond Coleman|
A common failure of hip-replacement implants is aseptic loosening of the bone-implant interface resulting from biological responses to debris from the implant material mediated mainly by cytokines released from inflammatory cells that activate bone-resorbing osteoclasts. An experimental study on female Wistar rats with femoral head replacement implants made of 316L stainless steel on bone resorption was undertaken. The periprosthetic osteolytic processes were assessed 7 and 14 days after implant surgery by x-radiography, histology, and histomorphometric analysis of tartrate-resistant acid phosphatase-positive (TRAP+) osteoclasts in the eroded bone area. Forty four rats were used in the study. Three potential drugs for inhibiting osteoclastic activity (Diacerhein, Indomethacin, Calcitonin) were studied to determine their effectiveness in reducing bone resorption. Histomorphometry and histochemistry revealed evidence for wear debris mediated osteolysis already by 7 days following implant surgery, though at this time there was no evidence of implant loosening as observed by X-radiography. In comparison with the control group, Diacerhein did not have any significant effect in preventing periprosthetic osteolytic processes (7 days P=0.018; 14 days P= 0.9), whereas Indomethacin had high preventive activity at day 7 (P<0.0001) but had no influence after 14 days (P=0.9). Calcitonin had some preventive activity at day 7 and day 14 post-operation (P<0.0001; P=0.018 respectively).
Key words: aseptic loosening-rat femoral head implant model-Diacerhein-Indomethacin-Calcitonin.