Hypertrophic Pulmonary Osteoarthropathy (HPOA)

Bone scan image shows diffuse increased uptake along the periosteum/cortical margins of both tibias (arrows), sparing the epiphysis, in this patient with lung cancer.

Facts: HPOA

• Clinical syndrome that includes clubbing of fingers/toes, periostitis of tubular bones of extremities and arthritis
• Originally described in association with pulmonary lesions
• Most commonly associated with pulmonary tumors (10% of cases)
• Patients can be asymptomatic or present with arthralgia, arthritis or bone pain
• Histopathology shows edema, mononuclear infiltrates and later osteoid formation of the periosteum
• Commonly involves long bones of forearms and legs, spared axial skeleton and skull

Imaging

• Symmetric periostitis along bony shafts, confined to diaphysis; do not involve joint
• Regular and undulating periosteal reaction
• On bone scan, there is diffuse increased uptake along the periosteum or cortical margins of long bones with sparing of epiphysis

Disorders Described with HPOA

• Pulmonary: cancer, metastasis, mesothelioma, infection and bronchiectasis
• Mediastinum: thymic cancer, thyroid cancer, esophageal leiomyoma, Hodgkin's disease
• Heart: cyanotic heart disease, bacterial endocarditis
• Others: liver cirrhosis, inflammatory bowel disease

Reference:

Vigorita VJ, Ghelman B, Mintz D. Orthopaedic Pathology, 2nd edition, 2007.