Testosterone Use May Raise Risks After Knee Replacement

A new study warns that men and women who take testosterone around the time they get a knee replacement might face more complications. Researchers followed over 13, 000 patients who had total knee surgery and compared those on hormone therapy with those not taking it. The data show that within three months of the operation, users had higher rates of blood clots in the lungs, pneumonia, kidney injury and sepsis. These risks stayed higher a year later, with more clots, heart problems, infections and kidney damage. Even five years after surgery, patients on testosterone were more likely to need additional knee work because of joint infections, bone fractures or loosening of the implant.The hormone is already popular—prescriptions jumped from 7. 3 million in 2019 to over 11 million in 2024—and is taken by both sexes for muscle, bone and sexual health. While testosterone has been linked to clotting in other contexts, the exact way it affects healing after knee replacement is still unclear. Experts say more research and peer‑reviewed studies are needed before drawing firm conclusions.