Question 1 · Radiology, Clinical
A 34-year-old footballer twists his right leg in a tackle. He has pain and swelling over the lower shin and some tenderness just below the knee on the outer side. A single AP radiograph of the lower leg taken in the department shows a spiral fracture of the distal third of the tibial shaft. Which imaging is most appropriate next?
- A. AP and lateral films of the whole leg, knee to ankle
- B. CT of the tibial shaft to plan internal fixation
- C. MRI of the leg to assess the surrounding soft tissue
- D. Isotope bone scan to look for further fractures
- E. No more films, as one view confirms the fracture
Show the answer and explanation
Answer: A. AP and lateral films of the whole leg, knee to ankle
A spiral tibial shaft fracture seen on one AP film, with tenderness near the fibular head, breaks both radiograph rules: two orthogonal views (one view can hide displacement and angulation) and imaging of the joint above and below (twisting injuries often injure the proximal fibula or the ankle). AP and lateral films of the whole leg from knee to ankle complete the assessment before any CT.
Why the other options are wrong
- B. CT of the tibial shaft to plan internal fixation: CT adds detail for complex or intra-articular fractures, but the basic films are not yet complete.
- C. MRI of the leg to assess the surrounding soft tissue: MRI shows soft tissue and occult fractures; this fracture is visible, and a second view and the joints come first.
- D. Isotope bone scan to look for further fractures: A bone scan is slow and non-specific and would not show alignment or a nearby joint injury.
- E. No more films, as one view confirms the fracture: One view can hide displacement and angulation, and it misses injuries at the joints above and below.
Key point: Every long-bone fracture needs two orthogonal views and imaging of the joints above and below, because one view hides displacement and the second injury is easily missed.
References
- Monteggia fracture-dislocation, Radiopaedia.org
- Tibial shaft fracture, Radiopaedia