Use of Massive Allografts to Manage Hydatid Bone Disease of the Femur

Hydatid disease is caused by the parasitic tapeworm Echinococcus granulosus. Osseous involvement accounts for 0.5% to 4% of cases in humans. Patients usually are from endemic zones and are initially asymptomatic, presenting with pain and edema at a later stage of disease. However, large lesions may present initially as pathologic fractures. Standard radiographs usually show expansive osteolytic lesions associated with initial cortical thinning, with compromise of the metaphysis or epiphysis, and may involve the diaphysis. The finding of periosteal reaction, osteocondensation, calcification, and clear delimitation of the lesions excludes the diagnosis of osseous hydatidosis. However, there are no specific radiographic signs in the affected bone. There is no generally accepted treatment algorithm for osseous hydatid disease. The usual treatment is surgical resection of the affected bone, followed by antihelmintic therapy. Some patients can be treated with intralesional procedures, such as curettage and allograft or polymethyl methacrylate cement. However, in some advanced cases, such as those with pathologic fractures or recurrences, wide resection may be needed. Several reconstructive alternatives have been reported, such as megaprosthesis, massive allograft, or alloprosthesis composite. The authors retrospectively reviewed 2 cases of femoral hydatidosis treated with wide resection and reconstruction with massive bone allograft. One patient had 5 years of follow-up, and the other had 9 years. No signs of relapse or complications were recorded, and functional outcomes evaluated with the Musculoskeletal Tumor Society scale showed excellent results. These 2 cases support the use of a massive bone allograft as a valid alternative to reconstruction after extensive bone resection for hydatidic disease.