Conventional radiography for the assessment of focal bone lesions of the appendicular skeleton: fundamental concepts in the modern imaging era.

Bone lesions of the appendicular skeleton can be caused by primary benign or malignant tumors, metastases, osteomyelitis, or pseudotumors. Conventional radiography plays a crucial role in the initial assessment of osseous lesions and should not be underestimated even in this era of modern complex and advanced imaging technologies. Combined with patient age, clinical symptoms and biology, and lesion features including location, solitary versus multiplicity, density, margin (transitional zone evaluated with Lodwick-Madewell grading score), and, if present, the type of periosteal reaction and matrix mineralization can narrow the differential diagnosis or offer a likely diagnosis. These radiographic features help guide further follow-up or management.