A 58-year-old man presented with a 2-month history of left knee pain. He had no history of trauma. Radiographs of the left knee revealed solid, minimally undulating periosteal reaction circumferentially, most notably along the distal femur (
image A). There was no fracture, joint effusion, or additional underlying osseous abnormality. A chest radiograph revealed a 5-cm right upper lobe mass (
image B), which was determined to be a moderately differentiated invasive adenocarcinoma. The periosteal reaction involving the femur was compatible with secondary hypertrophic osteoarthropathy (HOA) related to a primary lung malignancy. The patient was referred to oncology for further evaluation and management.
Hypertrophic osteoarthropathy is a syndrome characterized by clubbing and periostitis. Secondary HOA (previously referred to as
hypertrophic pulmonary osteoarthropathy) is most commonly associated with primary lung malignancies, particularly non–small cell lung carcinoma.
1 Periosteal reaction involving long bones in adults (without antecedent trauma or an underlying osseous lesion) should raise concern for secondary causes of HOA, such as lung disease.