Abstract
We present a case of a 68-year-old female with a history of hypertension and hypothyroidism who presented to the emergency department with right lower extremity pain and difficulty ambulating. An initial evaluation revealed an abnormal appearance of the right hip on MRI, concerning avascular necrosis versus acetabular compression fracture. Subsequent diagnostic procedures, including joint aspiration and radiologic bone biopsy, led to the surprising discovery of metastatic lung carcinoma on tissue pathology. Further work-up reveals lung primary adenocarcinoma with additional metastases to the brain as well. The patient underwent resection of acetabulum and complex surgical pelvis reconstruction, irradiation for brain metastases, and rehabilitation. This case highlights the importance of considering atypical presentations of metastatic malignancies and the need for a multidisciplinary approach to optimize patient management.