Calcific myonecrosis and the role of imaging in the diagnosis: a case report

Abstract

Calcific myonecrosis is a rare posttraumatic complication characterized by the replacement of muscles of one or more compartments with central liquefaction and peripheral calcification. We report magnetic resonance imaging (MRI) and CT imaging features of calcific myonecrosis arising 43 years after trauma. A 62-year-old man presented with a slowly enlarging mass in the left lower leg. Plain radiographs revealed a soft tissue mass with extensive amorphous calcification. The middle third of the tibia and fibula were eroded. MRI demonstrated peripheral ring enhancement on postcontrast fat-suppressed T1-weighted images. Volume-rendered images extracting only the images of bone and vessels also showed many branches from the tibialis posterior and peroneal arteries around the bone defect. During the operation, bleeding continued heavily from the vessels penetrating the cortical bone of the tibia, from the posterior compartment, and from the branches of tibialis posterior artery. The total blood loss was approximately 2,400 milliliters. There may be a causal relationship between massive bleeding and the hypervascularity of this tumor as evidenced by MRI and volume-rendering CT studies.

Figure 1.

Mid-portion of the calf viewed from the anterior aspect. A bulging, non-tender and elastic hard mass was covered with the thin and atrophic skin.

Figure 2.

Plain radiographs of the left leg revealed a soft tissue mass in the anterolateral part of the leg with extensive amorphous calcifications (arrow).

Figure 3.

Postcontrast CT showed a 4×6 cm sized mass with central low signal density (asterisk) and peripheral high density, suggesting fluid and peripheral calcification. The space between the tibia and fibula was also enhanced (arrow).

Figure 4.

Magnetic resonance imaging demonstrated that the contents of the masses were isointense with muscles on T1-weighted images and hyperintense on T2-weighted images, with peripheral low signal intensity foci representing calcification. Postcontrast fat-suppressed T1-weighted image showed peripheral ring enhancement (arrow).

Figure 5.

Volume-rendered image extracting only the images of bone and vessels showed many branches from the tibialis posterior artery and peroneal artery around the bone defect.