ESR1 and rheumatoid arthritis: BMD, bone mineral density; BMI, body mass index; BR, buckling ratio; CSA, cross-sectional area; CSMI, cross-sectional moment of inertia; CT, cortical thickness; DM, diabetes mellitus; FS, femoral shaft; GCs, glucocorticoids; IT, intertrochanteric region; NN, narrow neck; RA, rheumatoid arthritis; SERM, selective estrogen receptor modulator; TBS, trabecular bone score; Z, section modulus