Link found between intestinal bacteria, successful replacement of the joint

Having a healthy intestinal flora – the billions of bacteria housed in our intestines – could reduce the risk of infection as a result of knee and hip arthroplasty, while an intestinal flora unhealthy could increase the risk of infection.

More than a million Americans opt each year for a knee or hip replacement. The infection of an artificial hip or knee is a rare but debilitating complication. A study by researchers at Cornell's College of Engineering and the Hospital for Special Surgery (HSS) published July 8 in the journal Clinical orthopedics and related research shows that the health of the intestinal microbiome influences the risk of infection. The study of mice is a first step towards understanding the implications for humans.

"This research is in its infancy, but if it occurs in humans, it is possible that we may modify or repair the patient's intestinal microbiome before he undergoes hip replacement or hip replacement. knee, which could further reduce the risk of infection, "said Christopher Hernandez. , Associate Professor at the Sibley School of Mechanical and Aerospace Engineering and the School of Biomedical Engineering at Meinig, and first author of the journal.

To prevent infection, surgeons take several precautions during surgery. As a result, infections resulting from arthroplasty are rare and affect only 1% of operated patients. However, infections are the reason # 1 to replace an artificial knee and the third to replace an artificial hip.

In this study, researchers used mice equipped with tiny artificial knees developed by co-authors Dr. Alberto Carli and Dr. Mathias Bostrom, both surgical researchers at HSS in New York and also professors at Weill Cornell Medicine. The Cornell-HSS biomechanics program has linked HSS researchers to Cornell College of Engineering for more than 40 years, resulting in many advances in joint replacement technology.

The mouse knee prosthesis was originally developed to improve the design of implants and study how the bone grows in these implants. Carli then advanced the model to study infections.

In normal mice, markers of the immune system in the bloodstream increase during infection as the body reacts. But in the study, these markers did not increase in mice with unhealthy microbiomes that also developed infections. The results suggest that mice with unhealthy microbiomes may have a compromised immune system.

In the future, researchers will investigate whether patients could be prepared before surgery with emerging microbiome therapies or a readily available treatment, such as a probiotic regimen.