Prosthetic joint infections (PJI) are devastating complications. Our knowledge on hip fractureassociated hemiarthroplasty PJI (HHA-PJI) is limited compared to elective arthroplasty. The goal of this study was to describe the epidemiology, risk factors, management, and outcomes for HHA-PJI. A population-based (465,000) multicentre retrospective analysis of HHAs between 2006-2018 was conducted. PJI was defined by international consensus and treatment success as no return to theatre and survival to 90 days after the initial surgical management of the infection. Univariate, survival and competing risk regression analyses were performed. 1852 HHAs were identified (74% female; age:84±7yrs;90-day-mortality:16.7%). Forty-three (2.3%) patients developed PJI [77±10yrs; 56% female; 90-day-mortality: 20.9%, Hazard-Ratio 1.6 95%CI 1.1-2.3,p=0.023]. The incidence of HHA-PJI was 0.77/100,000/year and 193/100,000/year for HHA. The median time to PJI was 26 (IQR 20-97) days with 53% polymicrobial growth and 41% multi-drug resistant organisms (MDRO). Competing risk regression identified younger age [Sub-Hazard-Ratio(SHR) 0.86, 95%CI 0.8-0.92,p<0.001], chronic kidney disease (SHR 3.41 95%CI 1.36-8.56, p=0.01), body mass index>35 (SHR 6.81, 95%CI 2.25-20.65, p<0.001), urinary tract infection (SHR 1.89, 95%CI 1.02-3.5, p=0.04) and dementia (SHR 9.4, 95%CI 2.89-30.58,p<0.001) as significant risk factors for developing HHA-PJI. When infection treatment was successful (n=15, 38%), median survival was 1632 days (IQR 829-2084), as opposed to 215 days (IQR 20-1245) in those who failed, with a 90-day mortality of 30%(n=12). There was no significant difference in success among debridement, excision arthroplasty or revision arthroplasty. HHA PJI is uncommon but highly lethal. All currently identified predictors are non-modifiable. Due to the common polymicrobial and MDRO infections our standard antibiotic prophylaxis may not be adequate HHA-PJI is a different disease compared to elective PJI with distinct epidemiology, pathogens, risk factors and outcomes, which require targeted research specific to this unique population.
International and national predictions from the late 1990s warned of alarming increases in hip fracture incidence due to an ageing population globally. Our study aimed to describe contemporary, population-based longitudinal trends in outcomes and epidemiology of hip fracture patients in a tertiary referral trauma centre. A retrospective review was performed of all patients aged 65 years and over with a diagnosis of fractured neck of femur (AO classification 31 group A and B) admitted to the John Hunter Hospital, Newcastle, New South Wales between 1st January 2002 and 30th December 2009. Datawas collated and cross referenced from several databases (Prospective Long Bone Fracture Database, Operating Theatre Database and the Hospital Coding Unit). Mortality data was obtained via linkage with the Cardiac and Stroke Outcomes Unit, Planning and Performance, Division of Population Health. Main outcome measures were 30-day mortality, in-hospital mortality, length of stay. The JHH admitted (427 ± 20/year, range: 391–455) patients with hip fractures over the 9 year study period. The number of admissions per year increased over the study period (p = 0.002), with no change in the age-standardised incidence (p = 0.1). The average age (83.5 ± 0.2) and average percentage female (73.7%) did not change. There was an overall trend to decreased 30-day mortality from 12.4% in 2002 to 7% in 2009 (p = 0.05). The factors that were associated with increased mortality were age (p < 0.0001), male gender (p = 0.0004), time to operating theatre (p = 0.0428) and length of stay (p < 0.0001). In accordance with national and international projections on increased incidence of geriatric hip fractures, the incidence of fractured neck of femur in our institution increased from 2002–2009, reflecting our ageing population. 30-day mortality improved and longer length of stay corresponded with increased 30-day mortality.
