The dripping candle wax sign of melorheostosis

Abstract

Melorheostosis is a rare benign bone disease including dysostosis and sclerosis. Dripping candle wax presence is a common and typical sign of melorheostosis. This sign appears as irregular hyperostosis of the cortical bone which is likened to melted wax flowing down one side of a candle. It can sometimes cause pain, stiffness joint, or limitation of motion in the affected areas implicitly but mostly has no symptoms. It is usually observed on plain radiography; its appearance is generally hyperplasia on one side of the bone. We report a 33-year-old male who has an incidental diagnosis of melorheostosis post-trauma.

Keywords: Dripping candle wax; Leri disease; hyperostosis; melorheostosis; sclerosing bone dysplasia.

Figure 1.

Radiographs of the chest (a), anteroposterior (b) and lateral (c) views of a lumbar spine showing hyperostosis involving 11th rib on the left side, and involving thoracic and lumbar vertebrae. This is a characteristic sign of melorheostosis and the appearance of cortical is irregular hyperostosis. It typically occurs on one side of the involved bone and has been likened to melted wax flowing down one side of a candle.

Figure 2.

Radiographs of the metacarpal, metatarsal, pelvis, and legs. (a) Radiographs of two hands demonstrating a hyperdense lesion in several bones with obliteration of the medulla in the middle finger of the left hand. (b) Radiographs of two feet with localized cortical hyperostosis of several metatarsal bones. (c) Radiographs of the pelvis showing cortical hyperostosis extending from left iliac bone to left femur. (d) Radiographs of two legs showing regional sclerosis of cortically based endosteal in the tibia and fibula with characteristic melted candle wax appearance (arrows).

Figure 3.

(a and b) Axial CT scan images showing hyperostosis involving 11th rib left, thoracic, and lumbar vertebrae. (c) CT reconstruction image of the coronal plane showing the left 11th entire rib with hypertrophy and sclerotic. (d) Sagittal reformatted CT image showing hyperostosis involving the anterior and posterior segment of thoracic vertebrae. Note the spinal canal is not narrow (arrows and circles).

Figure 4.

MRI of melorheostosis on T2-Weighted sequences (a, c, d, and e) and T1-Gado sequences (b and f). Images showing some areas of the ribs are enlarged and hypointensity of a signal on all pulse sequences. Hyperostosis of the vertebrae as a hypointense signal is also observed (arrows and circles).