ObjectiveThe purpose of this presentation is to familiarize the reader with the often subtle findings of peroneal tendon derangement on MRI examination.
Materials and methodsWe present four patients who were studied with MR (1.5 T) prior to surgical exploration of the peroneal tunnel. All patients had lateral ankle symptoms for > 6 months. Normal MR anatomy and an example of the peroneus quartus tendon are also shown.
ResultsSurgery revealed two peroneus brevis and three peroneus longus lesions. A "multipartite" appearance of the peroneus tendon on axial MR images, especially when paired with a "flame-shaped" appearance on more distal axial images, indicates a longitudinal tendon split. Both patients with peroneus brevis tendon splits had insufficient superior peroneal retinacula.
ConclusionPartial ruptures of the peroneal tendons characteristically take the form of longitudinal tendon splits. Axial MR images through the ankle and hindfoot can help distinguish peroneal tendonitis from longitudinal tendon splits.