Extra-abdominal aggressive fibromatosis is a benign fibroblastic neoplasia with an infiltrative nature and a high tendency of local recurrence. Here, we report on a very rare case of multicentric fibromatosis. Low complaints led to considerable size of the tumours. The aim of the multimodal treatment was a limb salvage procedure. Adjuvant radiation therapy and chemotherapy was necessary because of the renunciation of wide resections in favour of the functionality of the limb.