# Occult Femoral Neck Fracture Misdiagnosed as Septic Arthritis: A Case Highlighting Diagnostic Challenges in Busy Emergency Settings

## TL;DR

A case is presented where a hip fracture was initially misdiagnosed as septic arthritis, highlighting diagnostic challenges in emergency settings.

## Contribution

This case emphasizes the need for advanced imaging in hip trauma when initial radiographs are inconclusive.

## Key findings

- Initial radiographs failed to detect an occult femoral neck fracture.
- CT scan revealed a basicervical femoral neck fracture after initial misdiagnosis.
- Persistent pain and incongruent clinical signs should prompt further imaging.

## Abstract

Occult femoral neck fractures are a diagnostic challenge in busy emergency settings, especially when initial imaging is unremarkable. Confounding clinical features, temporary response to analgesia, and raised inflammatory markers can lead to misdiagnosis, delaying definitive care. We present a case of a 52-year-old male who initially presented with right hip pain following a fall. His radiographs were unremarkable, and he was discharged after pain control. He re-presented three days later with worsening hip pain, inability to weight bear, and confusion. Raised inflammatory markers led to a presumptive diagnosis of septic arthritis, but a computed tomography (CT) scan ultimately revealed a basicervical femoral neck fracture. The patient underwent successful open reduction and internal fixation (ORIF). This case underscores the importance of maintaining a high index of suspicion for occult fractures, especially in patients with persistent or worsening pain and early representation. It also highlights the limitations of plain radiography in hip trauma. CT or magnetic resonance imaging (MRI) should be considered when clinical signs are incongruent with imaging findings.