A routine radiograph of a 35-year-old woman shows undulating cortical thickening along the anteromedial shaft of the tibia, described as resembling 'dripping candle wax', with no associated soft tissue mass or periosteal reaction. The most likely diagnosis is:

• A Melorheostosis ✓
• B Osteopetrosis
• C Paget disease of bone
• D Chronic osteomyelitis with involucrum

Explanation

Melorheostosis is a rare sclerosing dysplasia characterised by flowing, wavy cortical hyperostosis along the length of a long bone, classically likened to dripping candle wax, and it typically follows a sclerotome distribution. Paget disease causes bone expansion with cortical thickening but also coarsened trabeculae and altered bone texture, while osteopetrosis diffusely increases bone density throughout the skeleton rather than in a flowing segmental pattern.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.