# Trends in surgical management of septic arthritis of the knee: a 16-year observational study of 4,809 surgeries in Sweden

## TL;DR

This study tracks a rising trend in knee surgeries for septic arthritis in Sweden from 2008 to 2023, especially in older men and certain regions.

## Contribution

The study provides the first 16-year analysis of surgical trends for septic arthritis in Sweden, including future projections.

## Key findings

- The incidence of knee surgeries for septic arthritis increased from 3.4 to 4.6 per 100,000 inhabitants between 2008 and 2023.
- Men and older adults (65–84 years) had the highest rates of surgeries.
- Regional disparities were observed, with Jönköping, Jämtland, and Kalmar having the highest incidence rates.

## Abstract

Septic arthritis of the knee is a serious condition that requires prompt surgical intervention to prevent irreversible joint damage and systemic complications. Incision and debridement is the standard treatment approach for managing knee septic arthritis. However, limited research exists on long-term trends in these surgical procedures. This study aims to analyse the trends in knee incision and debridement surgeries for septic arthritis in Sweden over a 16-year period (2008–2023), focusing on demographic variations and projections through 2030.

A retrospective, population-based study was conducted using data from the Swedish National Patient Register (NPR) for the period of January 1, 2008, to December 31, 2023. All patients aged ≥ 15 years who underwent knee incision and debridement surgery for septic arthritis were included. Demographic data were categorized by age, sex, and geographical region. Incidence rates were calculated per 100,000 inhabitants, and Poisson regression models were used to analyse temporal trends and project future surgical incidence rates through 2030.

A total of 4,809 knee incision and debridement surgeries were performed between 2008 and 2023 in Sweden. Men accounted for 3,100 surgeries, compared to 1,709 for women. The highest number of surgeries occurred in 2023 (n = 404). The most affected age groups were 65–74 years (1,161 surgeries) and 75–84 years (1,127 surgeries). The overall incidence increased from 3.4 to 4.6 per 100,000 over the study period, with men consistently having higher rates. Significant regional variations were observed, with Jönköping, Jämtland, and Kalmar reporting the highest incidence rates. Projections suggest the incidence will continue to rise, reaching 4.6 per 100,000 by 2030.

The incidence of knee incision and debridement surgeries for septic arthritis in Sweden has steadily increased over the past 16 years, particularly among older adults and men. Significant regional disparities exist, highlighting the need for targeted interventions. Projections suggest that the burden of septic arthritis will continue to rise, necessitating enhanced preventive measures, early diagnosis, and resource planning to meet future healthcare needs.

The online version contains supplementary material available at 10.1186/s12891-026-09573-8.