Dose-dependent effects of estrogen-enriched bone cement on membrane quality in the Masquelet technique: experimental rat model

Objective: The Masquelet technique is a 2-stage surgical method used for the reconstruction of critically sized bone defects due to various etiologies. Estrogen is known to have anabolic effects on bone metabolism. In this study, based on literature data, the aim is to systematically evaluate the histological and immunohistochemical effects of adding different doses of estrogen to polymethylmethacrylate cement on induced membrane tissue. Methods: Twenty-eight male rats were included in the study and divided into 4 groups. Three experimental groups received different doses of estradiol, a subtype of estrogen mixed with bone cement, while a control group received only bone cement. Approximately 10 mm defects were created in single femurs of all rats. Bone cement appropriate for each experimental group was placed in these defects, and bone fixation was performed with mini plates and screws. Tissue samples taken from all animals at the end of the sixth week were evaluated by histological and immunohistochemical methods. Results: Histological and immunohistochemical evaluations of the induced membranes obtained at the end of the experiment revealed signs of bone formation in all subgroups. A significant increase in bone formation was observed with increasing doses in groups E1, E2, and E3 compared to the control group (P < .05). The histological scores of the study groups were found to increase statistically significantly with increasing estrogen dose (P < .05). Furthermore, immunohistochemical analyses revealed that the immuno-reactive scores for bone morphogenetic protein-4 and insulin-like growth factor-1 expression were significantly higher in the E3 group compared to the other groups (P < .05). Conclusion: In this study, it was found that enriching the cement content with estrogen during bone cement placement, the first step of the Masquelet technique, improved the quality of the formed membrane. This improvement in membrane quality is promising for increasing treatment efficacy and shortening the treatment duration. Cite this article as: Çiftçi MU, Purelku M, Özönder F, et al. Dose-dependent effects of estrogen-enriched bone cement on membrane quality in the masquelet technique: experimental rat model. Acta Orthop Traumatol Turc., 2026; 60(1), 0355, doi: 10.5152/j.aott.2026.25355.