[Hereditary multiple exostoses]

Hereditary multiple exostosis (HME) is a hereditary autosomal dominant disease in which multiple exostoses occur. Typically, the exostoses are primarily located at the metaphysis and migrate with continued growth towards the diaphysis. Clinical problems are caused by local pain, impingement of muscle tendons and neurovascular structures, malformation - especially in the forearm - and malignant transformation - especially exostoses at the trunc and pelvic girdle.A causal therapy is currently not available. Mechanical irritation is an indication for resection of the exostosis. Axial deviation of the lower extremity is treated according to the same principles as primary malalignments (temporary hemiepiphysiodesis/corrective osteotomy).The indication for correction of axial deviation at the upper extremity depends on age, extent as well as functional and cosmetic impairment. This should be discussed with the patient in detail. The patient has to be informed about the risk of malignant transformation after cessation of growth. Growing mass or new occurrence of symptoms after end of growth are suspicious and require further diagnostic examinations.