Introduction: Plantar fibromatosis, or Ledderhose's disease, is a fibrous proliferation arising within the plantar fascia end exhibiting typical clinical nodular features. The lesion appears as a firm single thickening or a nodule, occasionally painful, localized to the medial portion of the sole of the foot. This unusual condition has not been extensively studied with US and very little has been written about it.
Material and methods: In 1998-99, six patients with plantar fibromatosis were submitted to US with 13 MHz linear array and 20 MHz mechanical annular array probes. All patients were examined in prone recumbency with the probe positioned on the sole of the foot. Only some of them were subsequently submitted to surgery.
Results: Plantar fibromatosis exhibited an almost pathognomonic pattern and US proved to be a quick, noninvasive and cost-effective technique to confirm clinical diagnosis. The nodule is typically single and isoechoic, with maximum diameter of about 1 cm, inhomogeneous internal structure and few thin hyperechoic septa. The nodular fibrous proliferation adheres with the major axis along the plantar fascia; it exhibits clear-cut margins and US beam transmission is good. No calcifications or fluid collections are seen within the nodule. Color and power Doppler show no flow inside.
Conclusions: US is an adequate tool for the study of plantar fibromatosis.