Hypertrophic Osteoarthropathy: Clinical and Imaging Features

Hypertrophic osteoarthropathy (HOA) is a medical condition characterized by abnormal proliferation of skin and periosteal tissues involving the extremities and characterized by three clinical features: digital clubbing (also termed Hippocratic fingers), periostosis of tubular bones, and synovial effusions. HOA can be a primary entity, known as pachydermoperiostosis, or can be secondary to extraskeletal conditions, with different prognoses and management implications for each. There is a high association between secondary HOA and malignancy, especially non-small cell lung cancer. In such cases, it can be considered a form of paraneoplastic syndrome. The most prevalent secondary causes of HOA are pulmonary in origin, which is why this condition was formerly referred to as hypertrophic pulmonary osteoarthropathy. HOA can also be associated with pleural, mediastinal, and cardiovascular causes, as well as extrathoracic conditions such as gastrointestinal tumors and infections, cirrhosis, and inflammatory bowel disease. Although the skeletal manifestations of HOA are most commonly detected with radiography, abnormalities can also be identified with other modalities such as computed tomography, magnetic resonance imaging, and bone scintigraphy. The authors summarize the pathogenesis, classification, causes, and symptoms and signs of HOA, including the genetics underlying the primary form (pachydermoperiostosis); describe key findings of HOA found at various imaging modalities, with examples of underlying causative conditions; and discuss features differentiating HOA from other causes of multifocal periostitis, such as thyroid acropachy, hypervitaminosis A, chronic venous insufficiency, voriconazole-induced periostitis, progressive diaphyseal dysplasia, and neoplastic causes such as lymphoma. ^©RSNA, 2016.

A skeletal case of hypertrophic osteoarthropathy from the Canary Islands dating from 1000 BP

A left tibia, the distal right tibia, and the proximal four fifths of the right ulna and radius, probably belonging to an adult prehispanic man (antiquity of ≈1000 years BP) were found among commingled bone remains in a collective burial cave of the island of El Hierro, in the Canary Archipelago. All four bones show an intense periosteal bone formation, encrusting the preserved cortical bone of the diaphyses. Differential diagnosis include melorheostosis, syphilis, and leprosy, although the most likely diagnosis is hypertrophic osteoarthropathy, which is usually associated with lung neoplasm or non-malignant diseases leading to chronic hypoxemia. The marked bone proliferation, possibly due to a chronic condition, suggests that possibly the underlying illness was a non-malignant one.