Surgical site infections (SSI) occur in 0.7% of knee replacement surgeries and in 1% of hip replacements. SSI’s are the most common cause for rejection of the prostheses in hip replacement surgery, according to a number of studies presented in London at a conference of the European Center for Disease Prevention and Control (ECDC).
A Swedish study, presented at the conference, found that fracture patients who get an artificial hip have a significantly higher risk of infection than do people who undergo similar surgery due to a degenerative hip disease. Investigators found that joint infections occurred most often in cases with secondary fracture prosthesis. This was about 2.8% of cases—including cases where internal fixation had failed. Younger patients were at higher risk of infection than were older people.
The Swedish study revealed how difficult the treatment of postoperative infections can be. Only 40% of the cases could be cured. In 42% of the cases doctors brought the structural infection under control only after permanent resection arthroplasty. Almost all of these cases were fracture patients. Ten percent of the patients required a life-long antibiotic therapy and 8% died during their treatment.
“Adequate prophylactic measures are necessary, especially against staphylococcus aureus and coagulase negative staphylococci, the most decisive factors in infection among fracture patients, ” said the study’s main author, Piotr Kasina, M.D., from the Karolinska Institute, Stockholm. His research group examined the records of 3, 807 cases of hip replacement cases at the Stockholm South General Hospital between 1996 and 2005.
Researchers noted that the diagnosis of periprosthetic joint infections, and not just the treatment, presented challenges to orthopedic surgeons. An Austrian research team identified a new parameter for the detection of periprosthetic joint infections in revision arthroplasty. “We have compared the sensitivity and specificity of conventionally used biomarkers such as C- reactive protein [CRP] and leukocyte levels to that of PCT, IL-6 and interferon alpha. CRP has proven itself indeed as the best biomarker for diagnosing infections from periprosthetic revision surgery, but PCT and IL-6 were likewise shown to be helpful. They could be used as additional indicators when a diagnosis is not clearly conclusive, ” said Mathias Glehr, Ph.D., from the Graz University Hospital.
