According to a new study published on bmj.com, people who take bisphosphonates following joint replacement surgery tend to need less repeat surgery.
A significant number of patients require repeat surgery within 10 years following their knee or hip replacement due to infection, loosening, wear or other mechanical failures, even though hip and knee replacements are cost effective procedures.
According to some experts, oral bisphosphonates, used to prevent fractures and to treat common bone diseases like osteoporosis, could potentially improve the survival time of replacement joints through its ability to reduce bone resorption. However, there is only little and controversial evidence.
Research leader Professor Nigel Arden, at the University of Oxford, decided to examine whether the use of bisphosphonate can be associated with improved implant survival time.
Arden and team used anonymous data on three million UK primary care patients, screening all those aged 40 years or older who underwent hip or knee replacement surgery for osteoarthritis from 1986 to 2006 from the General Practice Research Database.
They defined those patients who received at least six months of bisphophonates therapy prior to revision surgery as bisphosphonate users, whilst non-users were defined as those who either never received bisphosphonates or who were administered with their first prescription after the revision surgery.
The researchers accounted for variables, such as smoking status and alcohol intake, age, sex, body mass index (BMI), use of vitamin D and calcium supplements, as well as previous fractures. Follow-up was for a maximum of 15 years after their operation to allow researchers to calculate the rate of revision surgery.
At five years, researchers noted a lower rate of revision in bisphosphonate users, and that bisphosphonate use was linked to a near double increase in implant survival time, meaning that for every 107 replacement patients taking bisphosphonates, one revision surgery would be avoided.
The researchers explain that this could be due to the fact that bisphosphonate therapy suppresses long term inflammatory response around the implant after surgery, which often results in bone loss and loosening of the implant.
The researchers claim that the protective effect of bisphosphonates demonstrated in this study can be assumed to apply for the majority of patients who undergo total hip or knee replacement surgery in the UK, although they recommend conducting further studies to confirm their findings.
Written by Petra Rattue