Prevention of early bone loss around the prosthesis by administration of anti-osteoporotic agents and influences of collared and non-collared femoral stem prostheses on early periprosthetic bone loss.

The current study aims to investigate the effect of anti-osteoporotic agents of collared and non-collared femoral stem prostheses on periprosthetic bone mineral density (BMD) after total hip arthroplasty (THA). 80 patients who received THA due to femur neck subcapital fractures were involved. The treatment groups were given fosamax, caltrate D and Xianlinggubao for oral administration, whereas the control groups were only given caltrate D. BMD at the greater trochiter around the femoral stem prosthesis and at the femoral shaft 1.5-1.0 cm away from the distal femoral stem was tested using dual-energy X-ray absorptiometry (DEXA) scan. Meanwhile, BMD at the same sites on the uninjured side was also tested. The BMD at both sites in all groups decreased after implantation. In the collared groups, no significant difference was shown between the injured and uninjured sides at 12 days or 3 months (p > 0.001). At 6 months after implantation, significant differences were displayed at both sites between the treatment and control groups (p < 0.001). In the non-collared groups, significant differences were displayed at both sites between the treatment and control groups at 6-months postimplantation (p < 0.001). No significant difference showed between the collared and non-collared groups show any at either site on either side (p > 0.05). DEXA scan can quantitatively determine bone loss around the prosthesis after THA. BMD around the prosthesis is correlated with administration of anti-osteoporotic agents. Fosamax + caltrate D + Xianlinggubao can prevent early bone loss around the prosthesis.