# Local soft tissue dissemination of large joint septic arthritis: A report of two cases

## TL;DR

This paper reports two rare cases where septic arthritis spread to soft tissues, causing severe complications in diabetic patients.

## Contribution

The paper presents two clinical cases highlighting the rare but severe complication of necrotising fasciitis from septic arthritis.

## Key findings

- Septic arthritis can lead to necrotising fasciitis, a rare but life-threatening condition.
- Diabetic patients are at higher risk for this complication and require prompt treatment.
- Early diagnosis and multidisciplinary care improve outcomes in these cases.

## Abstract

Septic arthritis (SA) is a surgical emergency that can result in joint destruction and systemic sepsis. Local soft tissue dissemination of native joint SA leading to necrotising fasciitis (NF) is a rare but devastating complication associated with poorer outcomes.

We present two adult patients with poorly controlled diabetes who developed SA complicated by NF—one affecting the knee and posterior leg, the other the shoulder and anterior arm. Both required multiple joint washouts, serial wound debridements, intensive care unit (ICU) admission, and prolonged intravenous antibiotics. One patient sustained extensive soft tissue loss necessitating coverage with a biodegradable temporising matrix (BTM) followed by split-thickness skin grafting.

These cases highlight the clinical course of this rare but severe complication and emphasise the importance of early diagnosis, initiation of broad-spectrum intravenous antibiotics, and timely surgical intervention. We also outline a practical diagnostic and management framework, including antimicrobial selection post-arthrocentesis, the role of pre-operative imaging, and the rationale for selecting arthroscopic versus open joint debridement.

SA complicated by NF is a life- and limb-threatening condition that presents numerous diagnostic and therapeutic challenges. Early recognition and a multidisciplinary approach incorporating empirical antibiotics, targeted imaging, and prompt surgical management are essential to optimise outcomes.

•Septic arthritis can disseminate locally, causing necrotising fasciitis.•Local spread of joint infection is rare but carries high morbidity.•Diabetic and immunosuppressed patients are at greatest risk.•Delayed diagnosis worsens outcomes in this elusive complication.•A prompt multidisciplinary approach is required for optimal care.

Septic arthritis can disseminate locally, causing necrotising fasciitis.

Local spread of joint infection is rare but carries high morbidity.

Diabetic and immunosuppressed patients are at greatest risk.

Delayed diagnosis worsens outcomes in this elusive complication.

A prompt multidisciplinary approach is required for optimal care.