Sedimentation sign: a classical finding on tumorous calcinosis.

The authors describe the case of a man in his 60s who presented with progressive pain and swelling of the right hip. Imaging features showed a densely calcified lesion associated with 'sedimentation sign'. Laboratory tests revealed slight hyperphosphataemia. Surgical excision of the lesion was performed. Histological examination revealed chalky material surrounded by fibrosis and giant multinucleated cells, compatible with tumorous calcinosis. Patient made a full recovery. We report a rare case of tumorous calcinosis and compare this condition with its common mimics.