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The Erlenmeyer flask bone deformity in the skeletal dysplasias
Maha A Faden1, Deborah Krakow, Fatih Ezgu
1Clinical Genetics, Department of Pediatrics, Riyadh Medical Complex Hospital, Riyadh, Kingdom of Saudi Arabia. maha_faden@yahoo.com
American Journal of Medical Genetics. Part A
|May 16, 2009
Summary
Erlenmeyer flask bone deformity (EFD) is a radiographic finding linked to 20 disorders. This study classified EFD into three types, aiding in differentiating associated skeletal dysplasias and syndromes.
Area of Science:
- Skeletal Radiology
- Medical Genetics
- Orthopedics
Background:
- Erlenmeyer flask bone deformity (EFD) describes a specific distal femora abnormality characterized by absent modeling, cortical thinning, and a flattened curve.
- This finding has been observed in various skeletal dysplasias and syndromes.
Purpose of the Study:
- To identify disorders associated with EFD.
- To classify EFD into distinct types.
- To determine the consistency and variability of EFD within associated conditions.
Main Methods:
- Literature review and cohort study of 12 disorders.
- Interrogation of the International Skeletal Dysplasia Registry (ISDR) radiographic database (1988-2007).
- Classification of EFD into three groups: typical (EFD-T), atypical (EFD-A), and marrow expansion (EFD-ME).
Main Results:
- Twenty distinct disorders were found to be associated with EFD.
- EFD-T identified in frontometaphyseal dysplasia, craniometaphyseal dysplasia, and others.
- EFD-A seen in dysosteosclerosis and osteopetrosis; EFD-ME in conditions like Gaucher disease.
- EFD was not a uniform finding and showed variability in appearance and location.
Conclusions:
- The classification of EFD into three types (EFD-T, EFD-A, EFD-ME) aids in differentiating associated skeletal disorders.
- Radiographic analysis revealed variability in EFD presentation, impacting its diagnostic utility.
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