c l i n i c a l f o l i o s : d i s c u s s i o n

Aneurysmal Bone Cyst



Related narrative: Aneurysmal Bone Cyst

Aneurysmal bone cyst is an expansile benign tumor-like lesion of uncertain etiology occurring in the young (10-30 years of age). It contains an expansile lesion containing blood, multinucleate giant cells and connective tissue and is lined by a thin shell of bone. It is usually seen in the metaphysis of long bones. Symptoms result from the expansile nature of the lesion as in this case. Pathological fracture is rare due the usual eccentric location of the lesion.

Good exposure was obtained with a lateral approach for the location of this lesion. If exposure was limited, controlled hip dislocation would have been considered.

This type of lesion can be a manifestation of an underlying tumor, the most worrisome being chondroblastoma and osteoblastoma. It is critical to detect such pathology early and is the reason for the frozen section done in this case. Other lesions presenting in a similar manner include unicameral bone cyst, chondromyxoid fibroma, giant cell tumor and fibrous dysplasia.

The traditional autografting of the cavity with iliac crest bone is now supplemented with the option of bioactive cancellous allografting with bone morphogenic protein and calcium sulfate. The combination acts as an inductive and conductive scaffolding for ingrowth of new bone and avoids the morbidity of bone harvesting.

Other experimental therapeutic modalities include selective embolization of nutrient vessels and percutaneous injection of sclerosing agents or methyl methacrylate.


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Huvos A, Bone tumors: Diagnosis, treatment and prognosis, WB Saunders, 1991.

Capanna, et al, Unicameral and aneurysmal bone cyst, Ortho Cl NA, vol 27 #3, 7/96, pp. 605-614.

This page was last modified on 12-Dec-2000.