Effects of gender-affirming care on musculoskeletal makeup, function and health

This article explores the impact of gender-affirming care on the musculoskeletal system, enabling practitioners to better educate and treat transgender and nonbinary patients.  

An estimated 1.6% of U.S. adults identify as transgender or nonbinary, indicating their gender differs from the sex they were assigned at birth, according to a 2022 Pew Research Center survey. Individuals in the 18-to-29 age range reported these differences most frequently (5.1%), the next being 30– to 49-year-olds (1.6%) and then respondents aged 50 and up (0.3%).  

Many people with gender incongruence, a new ICD-11 diagnostic category involving “a marked and persistent incongruence between an individual’s experienced gender and the assigned sex,” pursue gender-affirming care. That makes it important for DCs to understand how this care can affect patients’ musculoskeletal makeup and health. 

What is gender-affirming care?

The World Health Organization (WHO) defines gender-affirming healthcare as “interventions designed to support and affirm an individual’s gender identity.” Additionally, these interventions can be psychological, behavioral or medical, and a person might undergo one type of treatment or a combination of interventions. 

Gender-affirming care can include counseling, hormone therapy and surgery. Interest in these options is increasing, with one 2023 cohort study reporting the number of people in the U.S. undergoing gender-affirming surgery almost tripled between 2016 and 2019. It added that breast and chest procedures occur most frequently (in 56.6% of more than 48,000 respondents), followed by genital reconstruction (35.1%).  

The goal of gender-affirming care is to help individuals achieve greater alignment between their gender identity and the rest of their lives. However, certain interventions can also impact their musculoskeletal system. 

Impact of hormone therapy on musculoskeletal makeup and function

Research published in the Journal of Clinical Endocrinology and Metabolism in February 2024 involved a literature review of gender-affirming hormone therapy (GAHT) effects. Within one year after starting testosterone therapy, trans men had increased muscle mass and strength. Within three years, they performed physical exercises, such as push-ups and sit-ups, at the same level as cisgender men, or men whose gender identity and assigned sex align. 

When trans women underwent feminizing hormone therapy, they experienced a roughly 30% increase in fat mass at the one-year mark. Their muscle mass also reduced by around 5%, continuing to decline for several years thereafter. While trans women tended to retain a higher level of absolute lean mass, no physical performance advantages were identified. 

Gender-affirming care and musculoskeletal health

A different review, this one published in the Physician and Sportsmedicine in April 2024, sought to identify the impact of GAHT on the health of transgender athletes. It found transgender women receiving estrogen therapy had a higher risk of bone fractures and ligament injuries. They may also have an elevated risk of stroke, venous thromboembolism (VTE) and decreased blood pressure. 

An in-depth analysis of considerations for treating transgender athletes shares that trans women taking the hormone estradiol often have lower bone mineral density and increased bone loss. It’s unclear as to why, such as whether their bone density was lower initially or if estradiol hormone levels were too low to offset bone loss. It’s also a possible trans women could have an increased risk of injuring their anterior cruciate ligament (ACL), according to the authors, though studies have not confirmed this. 

Treating patients with gender-affirming care

Helping patients understand the physiological changes they might experience when undergoing certain types of gender-affirming care enables them to know what to expect. It also allows them to more fully consider the effects of different types of care when deciding which interventions are right for them. 

Final thoughts on gender-affirming care

As more studies are conducted, researchers will learn more about various interventions and their impacts. Additional options are also likely to become available, allowing patients to better align their lives with their gender expression. In the meantime, DCs can help patients navigate the process by providing research-based information, as well as treatment plans with gender-affirming care effects in mind.