Fig. 5.

Tibialis anterior muscle herniation. Axial sonograms obtained over the anterolateral aspect of the middle third of the leg, without (a) and with (b) local compression through the transducer, (b) longitudinal sonogram, (d) tangential radiograph. In (a) the anterior fascia (black arrow) of the tibialis anterior muscle (TAm) is torn and allows herniation of the muscle. In (b) local pressure reduces the herniation. Longitudinal sonogram depicts the defect (black arrows) in the fascia. Radiograph shows focal bulging of the muscle