A 42-year-old female with complaints of left groin pain. Although the anteroposterior pelvic radiograph (A) was unremarkable, axial T-1 weighted magnetic resonance imaging (B) demonstrated a lesion involving the left acetabulum; biopsy revealed conventional chondrosarcoma. C, Ten years after resection and soft-tissue reconstruction, the patient has no pain and ambulated well with a shoe lift with only a mild Trendelenburg gait.