Clinical introduction

A 19-year-old man presented to the emergency department with a 2 day history of severe left-sided groin pain. There was no history of trauma or recent physical exercise. On examination the patient did not look unwell and his temperature was 37.4°C. The patient was unable to actively flex his left hip and passive movements were very painful. He was noted to ambulate with an antalgic gait. A pelvic X-ray was taken (figure 1).

Question

What is most likely diagnosis?

1. Musculoskeletal pain

2. Septic arthritis of the left hip

3. Osteomyelitis of the symphysis pubis

4. Osteitis pubis

Answer: C

Pelvic X-ray …