Metachronous Aneurysmal Bone Cysts in a Fourteen-Year-Old Girl: A Case Report and Review of the Literature

Aneurysmal bone cysts (ABCs) were first described by Jaffe and Lichtenstein in 19421. Eighty percent of these lesions occur during the first two decades of life2; the most common location is the metaphysis of long bones. To the best of our knowledge, only four cases of individuals with multiple ABCs occurring over a period of time (metachronous ABCs) have been described to date3-6 (Table I). The cases all have been similar in presentation, imaging, and pathology to solitary ABCs; the only difference has been regarding the sex of the patient. While solitary ABCs have been shown to be predominant in females (62%)7, the reported cases of metachronous ABCs have all occurred in males. We report the case of an adolescent girl with multiple ABCs presenting separately in the proximal part of the femur and the distal part of the humerus over a five-month period. The patient and her parents were informed that data concerning the case would be submitted for publication, and they provided consent. View this table: TABLE I Reported Cases of Metachronous Aneurysmal Bone Cysts A healthy and active fourteen-year-old girl presented to the sports medicine clinic with unilateral hip pain. She had no history of trauma or an activity-related injury. Radiographs demonstrated a well-defined (5.4 × 2.8 cm) oval lucent geographic lesion in the proximal part of the femur, which initially was thought to be consistent with a unicameral bone cyst. At the short interval follow-up, the pain had worsened, and a new palpable mass was noted. Additional radiographs revealed substantial interval progression of the lesion with extension into the adjacent soft tissues with expansion of the bone (Fig. 1). Fig. 1 Anteroposterior radiograph demonstrates a lucent geographic lesion with a well-defined border (black arrow) in the right hip. However, there is focal extension …