The risk for revision for prosthetic joint infection after primary hip replacement is multifactorial, but mainly driven by patient and surgical level factors with time-varying effects, according to a study recently published in the Lancet Infectious Diseases.
Hip replacement is a successful elective surgical intervention widely used to treat disabling joint pain mainly caused by osteoarthritis. However, some patients experience complications, with 1 of the most severe being prosthetic joint infection. Although uncommon, prosthetic joint infection is devastating and can lead to severe pain, poor function, reduced quality of life, and death. Treatment usually requires a complex revision surgery that is associated with further complications. In England and Wales, more than 1000 revision procedures are performed annually because of prosthetic joint infections of the hip. The risk of developing a prosthetic joint infection is influenced by nonmodifiable and modifiable patient, surgical, and healthcare characteristics. Identifying individuals at high risk for prosthetic joint infections helps the development of preventative strategies and optimizes the detection of prosthetic joint infections. Therefore, this observational cohort study investigated the overall and postoperative period-specific effects of patient, surgical, and health system factors on the risk for revision for prosthetic joint infections.
All patients who had a primary hip replacement (n=623,053) from the National Joint Registry for England, Wales, Northern Ireland, and the Isle of Man between 2003 and 2014 were included and analyzed. Each patient was followed for a minimum of 12 months, until the end of the observation period, or until the date of revision. Age, sex, ethnicity, body mass index, American Society of Anesthesiologists grade, and comorbidities were considered as patient characteristics. Surgical factors, including indication for surgery, anaesthesia type, thromboprophylaxis regime, surgical approach, hip replacement type, bearing surface, and occurrence of intraoperative complications, were considered. Health system factors, including hospital type, funding stream, country, operating surgeon grade, consultant involvement, volume of hip surgeries performed by the hospital, operating surgeon, and surgeon in charge were also considered. Associations were investigated by postoperative periods: 0 to 3 months, 3 to 6 months, 6 to 12 months, 12 to 24 months, and more than 24 months.
Several modifiable and nonmodifiable factors are associated with the risk for revision for prosthetic joint infection. At the patient level, men, younger patients, and those with high body mass index or high American Society of Anesthesiologists grades had an increased risk. Comorbidities including chronic pulmonary disease, diabetes, dementia, liver disease, congestive heart failure, and connect tissue or rheumatic diseases also increased the risk for revision for prosthetic joint infection, and some could potentially be optimized before surgery. Men were at higher risk than women in all periods. At the surgical level, early revision was higher in those receiving uncemented compared with cemented implants independent of bearing surface, but at later times, the risk was lower. Further, lateral surgical approach and use of femoral bone graft demonstrated increased risk as well. Factors at the health system level appear to be less important, with no marked sustained associations across the periods studied.
Overall, the investigators conclude, “It is important for clinicians to consider non-modifiable factors and factors that exhibit time-specific effects on the risk of prosthetic joint infection to counsel patients appropriately preoperatively.”
Lenguerrand E, Whitehouse MR, Beswisk AD, et al. Risk factors associated with revision for prosthetic joint infection after hip replacement: a prospective observational cohort study [published online July 25, 2018]. Lancet Infect Dis. doi: 10.1016/S1473-3099(18)30433-X.