Hereditary multiple exostoses: an educational review.

Area of Science:

• Orthopedics
• Genetics
• Radiology

Background:

• Hereditary multiple exostoses (HME) is an autosomal dominant disorder affecting 1 in 50,000 to 100,000 individuals.
• Characterized by the development of multiple osteochondromas, primarily on long and flat bones.
• Diagnosis is typically clinical and radiological, with genetic testing for ambiguous cases.

Purpose of the Study:

• To review the clinical presentation, pathogenesis, imaging characteristics, complications, and treatment of HME.
• To highlight the importance of multi-modality imaging in diagnosing and assessing HME.
• To emphasize the need for follow-up to rule out malignant transformation.

Main Methods:

• Review of current knowledge on HME.
• Discussion of diagnostic criteria including radiological findings (WHO criteria).
• Emphasis on various imaging techniques (radiography, CT, MRI, ultrasound, nuclear medicine) for lesion visualization and complication assessment.

Main Results:

• HME is associated with mutations in EXT-1 and EXT-2 genes.
• Common complications include skeletal deformities, fractures, bursitis, and neural/vascular issues.
• A significant risk (10%) of malignant transformation to secondary chondrosarcoma exists in HME patients.

Conclusions:

• Accurate diagnosis and assessment of HME rely on a combination of clinical and radiological evaluations.
• Imaging, particularly MRI and ultrasound for cartilage cap measurement, is crucial for detecting malignancy.
• Regular follow-up is essential for optimal patient care and monitoring potential complications, including malignant transformation.