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Ann Saudi MedAnn Saudi MedAnnals of Saudi Medicine0256-49470975-4466King Faisal Specialist Hospital and Research Centre 1758291610.5144/0256-4947.2007.49asm-1-49What's Your Diagnosis?A previously healthy 77-year-old man with a painful mass in the calf for two months Özbarlas Serdar *Kalacı Aydıner †Özkan Cenk *Togrul Emre *
* Department of Orthopaedics and Traumatology, Çukurova University Faculty of Medicine
† Department of Orthopaedics and Traumatology, Mustafa Kemal University Faculty of MedicineCorrespondence and reprint requests: Aydıner Kalacı, MD, Department of Orthopaedics and Traumatology Mustafa Kemal University Faculty of Medicine Hatay 31100, Turkey, T: +90-326-214 8661, F: +90-326-214 4977, kalaci@mku.edu.trJan-Feb 2007 27 1 49 50 01 8 2006 Copyright © 2007, Annals of Saudi Medicine2007This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
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A previously healthy 77-year-old man presented with a painful mass in the calf for two months. He had a history of blunt trauma 5 years ago and the injury had been treated conservatively. Physical examination showed a local tenderness and a fusiform, fluctuating mass measuring 15×6×6 cm in the anterolateral aspect of the right calf. The ankle showed a full range of motion with sensory and motor functions preserved. The results of laboratory tests, including glucose, alkaline phosphatase, calcium, phosphate and erythrocyte sedimentation rate were all normal. Plain X-ray and MRI of the calf were abnormal (Figures 1, 2).

What are the abnormalities seen in the plain radiographs and MRI?

What’s your differential diagnosis?

What’s the diagnosis?

Answer on page 55.

Figure 1 Anteroposterior (A) and lateral (B) radiographs of the cruris.

Figure 2a Frontal spin-echo T1-weighted MRI of the calf.

Figure 2b Axial T1- and T2-weighted MRI scan (proximal section) (left).

Figure 2c Axial T1- and T2-weighted MRI scans (distal section) (right).