What is Melorheostosis?
Melorheostosis is a rare bone disease characterized by abnormal growth of new bone tissue on the surface of existing bone. The abnormal bone growth mainly occurs in the long bones, is noncancerous, and does not spread from one bone to another. The new bone features a distinctive appearance on x-rays, often described as “flowing”, as it resembles dripping candle wax. The exact cause of melorheostosis is unknown.
Symptoms of Melorheostosis
Symptoms usually appear in childhood or adolescence. Pain is the major symptom, followed by stiffness and joint deformities. Melorheostosis progresses in childhood but ceases with maturity, sometimes leaving adults physically disabled. Other common symptoms include:
- Edema
- Hyperpigmented skin patches
- Vascular tumors
- Malformations
- Limited range of motion
- Enlarged or thickened limb
Diagnosis of Melorheostosis
Diagnosis is usually made through conventional radiography, while an MRI contributes to the assessment of soft tissue lesions. However, there is usually a low signal on MRI, making X-ray imaging the preferred diagnostic tool. Your doctor may order further tests such as radioisotope bone scans and biopsies to rule out other conditions.
Treatment for Melorheostosis
Treatment is aimed at reducing symptoms as there is no curative treatment for melorheostosis. Management helps to alleviate pain, restore movement of the affected limb, and correct deformity. Physical therapy, serial casting, braces, manipulations, and nerve blocks are common conservative options. Medications such as non-steroidal anti-inflammatory drugs (NSAIDs) are used, as well as steroids and sometimes narcotics.
Surgical options include:
- Limb and tendon lengthening
- Fasciotomies
- Osteotomies
- Excision of fibrous tissue and/or hyperostosis
- Arthrodesis
- Amputation
Surgical treatments are best performed after skeletal maturity is reached; however, deformities can recur.
Prognosis of Melorheostosis
Melorheostosis is not a life-threatening condition, but it can greatly affect one’s quality of life due to chronic pain which can persist even after surgery.
