The study, led by Dominik Szymski and colleagues at the University Medical Centre Regensburg in Germany, set out to fill a conspicuous gap in the medical economics literature. While the costs of treating a first periprosthetic joint infection, or PJI, have been examined in a number of national studies, almost no attention had been paid to what happens when that treatment fails. Registry data suggest that surgical treatment of an infected hip replacement fails in up to 30 percent of cases, and in more than 20 percent of infected knee replacements. Each failure forces patients back into the operating theatre for procedures that are longer, more complex and far more expensive than the original revision, involving compromised bone stock, poor soft tissue conditions and prolonged antimicrobial therapy.

To build their model, the researchers combined three streams of data. First, they drew on Eurostat figures for 2023 showing that 2.29 million primary hip and knee replacements were performed across 30 European countries, with Germany leading at more than 515,000 procedures, followed by France, Italy and the United Kingdom. Second, they applied published infection rates of roughly one percent, derived from an unweighted average across several international arthroplasty registries, to estimate that 22,794 of those primary implants became infected. Third, they layered on failure rates from recent registry studies to calculate how many of those infections, and how many of the roughly 23,900 aseptic revisions performed in the same year, would go on to require a septic re-revision. The answer: 8,629 repeat operations for infection across Europe annually.

Crucially, the team went beyond procedure counts to attach real money to each operation. Through a survey coordinated by the European Bone and Joint Infection Society’s country delegates, they collected hospital reimbursement figures for 13 countries, including Germany, France, Italy, the United Kingdom, Switzerland and Türkiye. For the remaining countries, they extrapolated costs by classifying nations into higher- and lower-income groups based on gross domestic product per capita, a method they validated with leave-one-out cross-validation. Each re-revision was categorised into one of three surgical strategies: debridement, antibiotics and implant retention, known as DAIR; one-stage exchange, in which the implant is replaced in a single operation; or two-stage exchange, in which the infected prosthesis is removed, antibiotics are given, and a new implant is placed only after the infection has cleared.

The results reveal a striking concentration of costs. Two-stage exchange procedures accounted for 82.8 percent of total expenditure despite representing 70.4 percent of all interventions, making them by far the dominant financial driver. In hip arthroplasty alone, re-revision after failed infection treatment cost an estimated 70.3 million euros, with Germany alone bearing more than 20.6 million euros. Knee replacements added another 41.3 million euros for re-infection treatment, with Germany and France the largest national contributors. Perhaps more surprising was the discovery of a hidden burden: infections arising after initially aseptic revisions, a population largely ignored in previous economic models, generated an additional 12 million euros per year. Ignoring this subgroup, the authors note, significantly underestimates the true socioeconomic weight of arthroplasty-related infection.

The economics of individual procedures tell their own story. A DAIR procedure for an infected hip costs hospitals roughly 10,654 euros, while a two-stage exchange costs 32,774 euros; for knees, the figures are 8,978 euros against 30,626 euros. That threefold difference means that patient selection for DAIR is not merely a clinical judgement but a decision with direct financial consequences. When DAIR is applied to patients whose infection is too chronic, whose implant is loose, or whose soft tissues are too compromised, the resulting failure pushes them into the most expensive treatment pathway available. Careful assessment of infection chronicity, implant stability and host comorbidity, the authors argue, carries measurable economic as well as clinical value.

How confident can we be in these numbers? The researchers stress-tested their model extensively. A deterministic sensitivity analysis varying key parameters, including infection incidence, failure rates and the proportion of two-stage procedures, by plus or minus 20 percent produced total costs ranging from 101.3 to 145.9 million euros. A Monte Carlo probabilistic analysis running 10,000 iterations yielded a median estimate of 126.2 million euros with a 95 percent credibility interval of 102.0 to 156.2 million euros. The 13 directly surveyed countries accounted for 79.8 percent of the total, with the GDP-based extrapolation contributing the remaining fifth. The authors are candid about the limitations of that extrapolation: cross-validation showed a mean absolute percentage error of 71 to 81 percent per country, meaning GDP per capita is an imperfect proxy for national reimbursement systems, although errors partially offset when aggregated across the continent.

The model also has boundaries that matter for interpretation. It captured only direct hospital payments, excluding outpatient care, rehabilitation, antimicrobial therapy, productivity losses and quality-of-life impacts. Drawing on published estimates that indirect costs multiply the direct burden two- to four-fold, the authors suggest the societal cost could plausibly reach 247 to 494 million euros annually, though they flag this as an illustrative rather than a modelled figure. The treatment strategy distribution was applied uniformly from a single English and Welsh registry, so the reported costs represent a projection of uniform practice rather than country-specific observations. Rare outcomes such as resection arthroplasty, arthrodesis and chronic fistula formation could not be included due to insufficient data.

What makes the study genuinely newsworthy are the counterfactual scenarios. If Europe cut PJI incidence by a quarter, through better perioperative prevention, screening and infection control, the model projects annual savings of 27.9 million euros, or 22.6 percent of the total, sparing an estimated 935 hip and 560 knee re-revisions every year. Alternatively, shifting half of the patients currently destined for two-stage exchange to one-stage procedures, where evidence supports it, would save a further 22.6 million euros annually. Combining both interventions would reduce the projected total to 78.2 million euros, a saving of 45.4 million euros, or 36.8 percent. These are not speculative laboratory promises; they are achievable through existing clinical pathways, provided that patient selection and care organisation improve.

The policy implications reach beyond prevention. The authors argue that many European reimbursement structures fail to reflect the true complexity of septic re-revision surgery, and that underfunding risks discouraging hospitals from accepting these high-risk, high-cost patients, potentially threatening access to specialised care. They point instead toward centralisation of treatment in dedicated PJI centres with multidisciplinary teams of surgeons, infectious disease specialists, microbiologists and plastic surgeons, an approach shown in prior studies to improve outcomes in musculoskeletal infection. Registry data confirm that septic revision history is among the strongest predictors of further failure, with risk concentrated in the first postoperative year, underscoring the value of close early surveillance. As European populations age and demand for joint replacement continues to climb, the message of this analysis is unambiguous: failure after infection treatment is not a rare exception but a frequent and costly event, and investing in prevention, smarter treatment algorithms and adequately funded specialised care would pay for itself many times over, in both human and financial terms.

Subject of Research: Health-economic modelling of the costs of septic re-revision surgery for periprosthetic joint infections across 30 European countries

Article Title: Socioeconomic burden of septic re-revision surgeries for periprosthetic joint infections in Europe – a comprehensive analysis of re-revision costs

Article References: Szymski, D., Baertl, S., Walter, N., Rupp, M., Hierl, K., & Alt, V. (2026). Socioeconomic burden of septic re-revision surgeries for periprosthetic joint infections in Europe – a comprehensive analysis of re-revision costs. Journal of Bone and Joint Infection, 11(4), 523-533. https://doi.org/10.5194/jbji-11-523-2026

Image Credits: AI Generated

DOI: 10.5194/jbji-11-523-2026

Keywords: periprosthetic joint infection, septic re-revision, hip arthroplasty, knee arthroplasty, two-stage exchange, DAIR, health economics, Eurostat, reimbursement costs, Europe, arthroplasty registries, infection prevention