While there is much attention given to improving patient outcomes by developments in implant design and surgical approach, it is the risk of infection following total joint surgery that is often most concerning for both orthopaedic surgeons and hospital administration alike. The main issue with these sorts of infections is that symptoms can take days, weeks or possibly even months to manifest into noticeable problems. By this time a connection between the surgery and the infection might be so vague that it is unnatural to draw the conclusion that the surgery itself was in fact the cause if the infection. What is clear is that with the advancements of medical science and technology to aid surgeons, the likelihood of an infection taking place during, or after surgery, is minimal and can almost always be attributed to human error.
The current infection rate following arthroplasty is about 1%. Revision procedures for these infections result in greater blood loss, longer operating times, more frequent complications along with increases in the total number of hospitalization and longer hospital stays.
The University of Texas Health Science Centre have collaborated with Rice University and Shriners Hospital for Children in the USA to develop an application that may potentially reduce implant-associated bone infections. The researchers, led by Catherine Ambrose, Ph.D, an associate professor in the Department of Orthopaedic Surgery at the UTHealth Medical found that porous metal implants that were coated with the microspheres prevented infection in 100% of the 11 specimens studied. In the tissue and bone surrounding the implants that were not coated with the antibiotic delivery system, infection occurred at a 64% rate.
The Universities’ press release quoted Ambrose as saying that the microspheres would appear to overcome a number of obstacles health care teams currently face when treating osteomyelitis-bone infection. The microspheres could be administered directly at the surgical site, eliminating the need for systemic antibiotics that impact the entire body. Ambrose noted that, “because the antibiotic delivery system is microscopic in size, it does not appear to interfere with the healing after a total joint replacement. These findings demonstrate the potential of antibiotic microspheres and have recently been published in the Journal of Bone and Joint Surgery.
The Australian National Joint Replacement Registry reported 48,783 total knee replacements and 38,432 total hip replacements in 2013. With average bed costs exceeding $700 per day in Australia, even halving the infection rate will have a significant impact on our healthcare system. The development of antibiotic-coated implants may be the difference here.