[Solitary calcaneal cyst].

Differential diagnosis of solitary calcaneal cysts extends from benign cysts to malignant tumours. In all, 10-50% of these cysts are located at the centre of the calcaneal body in the form of intraosseous lipomas. Among our patients treated over a period of more than 20 years, there were four who underwent surgery for calcaneal cysts; the respective histological findings showed three lipomas and one tuberculoma. The average age of these patients corresponded to that of Milgram's study. It should also be remarked that all four patients came from a region in which mining was of central economic importance. Our experience has shown that such cysts should be surgically removed and filled with plastic spongiosa material in order both to check whether the cysts are benign or malignant and to avoid an imminent spontaneous fracture of the heel bone.