diaphyseal aclasis
Pronunciation: die-ah-FIZ-ee-ul ah-KLAY-sis
A hereditary condition characterized by multiple cartilaginous exostoses arising from the metaphyses of long bones.
Full Definition
Diaphyseal aclasis, also known as hereditary multiple exostoses (HME), is an autosomal dominant skeletal disorder characterized by the formation of multiple benign cartilage-capped bony projections (exostoses) from the metaphyses of long bones. The condition results from mutations in genes affecting cartilage development and causes progressive deformity, growth disturbances, and potential functional limitations. In orthopedic oncology, diaphyseal aclasis is significant because exostoses carry a small but definite risk of malignant transformation to secondary chondrosarcoma, particularly in axial locations. Patients require lifelong surveillance for changes in lesion characteristics that might indicate malignant transformation.
Usage
Usage note: The term 'aclasis' means 'lack of breaking away' and refers to the failure of normal bone remodeling.
In Context
- "The patient's family history and multiple lesions were consistent with diaphyseal aclasis." — Genetic counseling note
- "Regular surveillance for malignant transformation is essential in patients with diaphyseal aclasis." — Long-term follow-up plan