Fig. 36.

Infection. Metatarsal. a, b Axial colour Doppler (a) and sagittal conventional (b) sonograms. c, d axial T1-weighted MR images obtained before (c) and after (d) i.v. contrast administration. US shows a focal break (white arrow) of the superior cortex of the first metatarsal (MT1) related to the previous surgery for chronic osteomyelitis. An abscess (white arrowheads) of the adjacent soft tissues appears on US as an irregular area with peripheral hyperaemia and a fluid–fluid level (void arrowheads). MRI confirms the US appearance. A small fluid collection is located at the plantar aspect of the abscess (white asterisk) surrounded by an area of contrast enhancement (black asterisk)