Surgical management of calcaneal unicameral bone cysts

Unicameral bone cysts are not seen commonly in the calcaneus, Little is kno wn about the etiology and natural history of these lesions. Calcaneal cysts often are symptomatic, although some of these lesions are detected as inci dental findings. Treatment has been advocated based on the fear of patholog ic fracture and collapse. Several published series have been divided in the ir favor for either open treatment or injection management. These series ar e small, and the optimal treatment is still in question. The current study compared the efficacy of methylprednisolone acetate injection treatment wit h curettage and bone grafting in the treatment of unicameral bone cysts of the calcaneus, Ail patients treated for unicameral bone cysts of the calcan eus during the past 7 years at two institutions were reviewed. Eleven patie nts met inclusion criteria. All diagnoses were confirmed radiographically o r histologically. Demographic information, presenting complaints, diagnosti c imaging, treatment modalities, and outcome were analyzed. Long term radio graphic and subjective followup was obtained. Eighteen surgical procedures were performed on 11 patients with 12 cysts. Nine injections performed on s ix patients failed to show healing of the cyst. Nine cysts treated with cur ettage and bone grafting showed cyst healing. At mean followup of 28 months (range, 12-77 months), all 11 patients had no symptoms; there were no recu rrences of the cyst in the nine patients who underwent bone grafting and pe rsistence of the cyst in the two patients who underwent injection therapy. This review reports one of the largest series of cysts in this location. Th e results indicate that steroid injection treatment, although useful in oth er locations, may not be the best option for the management of unicameral b one cysts in the calcaneus, Curettage and bone grafting yielded uniformly g ood results.