Hormone replacement therapy (HRT) taken for over a year by women after a knee or hip replacement appears to cut the risk of repeat surgery being needed by more than half, according to research published today.
Figures from England and Wales show that two in every 100 operations have to be carried out again within three years because of osteolysis, where parts of the implant “seep” into surrounding tissue.
The body’s immune system reacts against the seepage, causing inflammation which destroys the bone around the implants. Each year, 160,000 such operations are carried out in 400 hospitals, but the numbers are expected to rise sharply in coming years as the population ages.
Women who took HRT for six months, or more, after surgery were 38 per cent less likely to require repeat surgery, while those who did so for more than a year were more than 50 per cent less likely to need it, researchers found.
Joint replacements will also increase in coming years because of the impact of obesity on individuals, the researchers stated in their study, which is published online by the Annals of the Rheumatic Diseases.
Low levels of oestrogen are blamed for causing bones to thin, while HRT is believed to help conserve bone thickness. However, the study found that taking HRT before surgery made no difference to whether implants failed or not.
