A RARE ENTITY - THE CALCANEUS INTRAOSSEOU S GANGLION

The authors report a rare case of a histologically proven intraosseous ganglion found in the calcaneus. A 59 year old carpenter was referred to our institution because of progressive talalgia with swelling of t he hindfoot, increasing with prolonged standing and walking at job. X rays showed a multilobular radiolucent cyst developed in the anterior part of the left calcaneus, outlined by a rim of sclerotic bone. A lat eral cortical split revealed by CT was deemed to be a traumatic comuni cation with the soft tissue. At biopsy, a gelatinous and hematic conte nt was noted but pathologic examination of the cyst walls failed to re veal the diagnosis; there were no malignant cells. 5 weeks later, the cyst and its contents were excised through lateral approach and the de fect filled with cancellous bone graft. At pathological examination, a final diagnosis of ganglion cyst was determined, One year after surge ry, the patient was asymptomatic; no sign of recurrence was observed. Intraosseous ganglia are benign subchondral cysts which rarely involve foot bones. When pain becomes consistent and swelling occurs because of overlooked fracture, malignant bone tumors should be ruled out. His tological examination is mandatory to confirm the diagnosis. Excision of the cyst and bone grafting are effective; recurrence is infrequent.