## 4 Discussion
Moreover, [PERSON] et al. proved that alendronate prevents the periprosthetic BMD loss and lumber spine at one year postoperatively [18]. [PERSON] et al. nevertheless showed that the protective effect of alendronate is not maintained at 5 years postoperatively [16]. Regardingsimvastatin, there are limited data on its use following total hip arthroplasty. [PERSON] et al. showed that simvastatin, when administered one year postoperatively, can prevent BMD loss in ROI 1, 2, 6, and 7 [19]. Regarding the osseointegration process, simvastatin could improve the osseointegration process of the femoral component, as shown in an animal mode [20]. Regarding bone serum markers, we opted for both a bone formation marker (alkaline phosphatase) and a bone resorption marker (\(\beta\)-CTx). These markers are one of the most commonly used for the characterization of bone metabolism. During the three determinations, the beta cross-laps (\(\beta\)-CTx) marker decreased in the alendronate group; it remained at a similar level in the simvastatin group while increasing in the control group. This result shows that the bone resorption process is the lowest in the alendronate group, while simvastatin also proved improved results compared to the control group. Regarding alkaline phosphatase (ALPL) marker, simvastatin showed the greatest increase at 1 month postoperatively, while alendronate showed the greatest increase at 2 months postoperatively. From the bone serum marker point of view, alendronate can prevent excessive periprosthetic bone loss at one month postoperatively. Moreover, simvastatin also protects against periprosthetic bone loss, but the results were not statistically significant. The lack of side effects related to alendronate and simvastatin in our patients shows that the treatment is safe for patients to use. The lack of side effects can also be explained by the short-term treatment administration. Because the patients were not allowed full weight-bearing postoperatively, these results may not apply to those cases where the patients are allowed immediate full weight-bearing. The reason is that full weight-bearing might limit the bone resorption process postoperatively, thus reducing the effect of alendronate and simvastatin on the periprosthetic bone. We found no studies to sustain the mention above, but the extra loading should only prove beneficial in limiting the periprosthetic bone loss, according to Wolff's Law [21]. Regarding the osseointegration process, this is difficult to quantify with standard imaging techniques, and no studies are available to compare the osseointegration process in the partial and full weight-bearing postoperative protocol. Limitations of this study include a low number of patients, lack of patient randomization, lack of non-osteoporotic patients, the short time follow-up, lack of functional scores, and lack of aseptic loosening rate. Moreover, the groups were not comparable in terms of hyperlipidemia, which also represents a limitation of our study. As this is the first study to compare alendronate and simvastatin in the early postoperative setting, further studies are needed to confirm our result before alendronate can be widely used for the prevention of femoral stem migration when early full weight-bearing is permitted.