Peritrochantric Unicameral Bone Cyst in a Nine-year-old Girl: A Case Report and Review of Literature

The unicameral bone cyst (UBC) is a benign osteolytic lesion mostly found in the metaphyseal part of long bones in children. It is important as it can cause growth plate involvement, pathological fractures, and deformities of the affected limb. Our goal to report this case was to emphasize that hip area pathologies can be represented with knee pain and discomfort.

The patient was a nine-year-old girl with a bone cyst in the right proximal femur, with functional knee pain and limping. The diagnosis was made after two years of pain in the knee area. As the cyst was symptomatic and the signs of impending pathological fracture were seen, the lesion was managed by a surgical method of curettage and fibular strut allograft and proximal humerus locking plate.

The patient has been examined for knee joint problems for a long time, and her femur bone cyst was diagnosed after two years of pain; while it could become a pathologic fracture or involve the growth plate and cause growth arrest of the limb, which could affect patientchr('39')s quality of life for a lifetime. Therefore, in children with chronic knee pain, careful assessment of the hip area is recommended.