The Role of Sex and Gender in Transgender Bone and Other Musculoskeletal Health.

Musculoskeletal changes occur with gender-affirming hormonal therapy (GAHT) and gender-affirming surgery (GAS) used in the care of transgender adolescents and adults. Survey results have shown that orthopaedic surgeons desire to care for transgender individuals but express concern over a knowledge deficit. This article reviews the physiology and pathophysiology that may occur with GAHT and GAS. Transgender women have lower bone mineral density (BMD) prior to GAHT than cisgender men. Limited fracture data would suggest that transgender women >50 years of age have fracture rates similar to those of cisgender women. Transgender men have normal BMD prior to GAHT and are not at an increased risk for fracture compared with cisgender women. The use of puberty-blocking medications in the care of transgender youth does result in a decline in BMD, which returns to baseline with GAHT, but the effect of delaying puberty on maximal BMD and the lifetime fracture risk are unknown. At present, dual x-ray absorptiometry (DXA) is used to measure BMD and assess fracture risk. Attention should be paid to using the appropriate reference group in the interpretation of DXA for transgender individuals. Promote musculoskeletal health by ensuring appropriate calcium, vitamin D, weight-bearing activity, and a healthy lifestyle. Adherence to GAHT needs to be encouraged to avoid bone loss. Data with regard to therapy for osteoporosis in transgender patients have been lacking, but, at present, use of available therapies is expected to be effective. Information with regard to differences in other musculoskeletal health issues such as joint injuries has been lacking in transgender individuals.