Erlenmeyer Flask Deformity

Philippe Gaucher ¹ described the condition that now bears his name in 1882. This cerebroside disorder leads to packing of the bone marrow with lipid-laden reticuloendothelial cells and causes modeling abnormalities that are especially well demonstrated in the metaphyses of the long bones. The earliest detailed descriptions of the clinical, radiologic and pathologic findings were presented in two separate articles ² , ³ , from the same case material, in 1926. The radiologist involved, Sven Junghagen (Rontgeninstitut Lund), described the abnormal contour of the ends of the long bones in a 3-year-old girl who had clinical and radiographic follow up over a 2-year period. However, it was A.W. Fisher (University of Frankfurt) who seems to have first used the term flask-shaped (flaschenformige) in an article 2 years later ⁴ (Figure 1). He discussed the long bone changes, especially those in the distal femur, in 16 cases. Nine of the patients had a diagnosis of Gaucher’s disease. The others had diagnoses that included: Picks disease, chronic osteomyelitis, arthritis deformans and pernicious anemia. Fisher emphasized that the differences and similarities between cases, that may occur in the shape of the distal femur, are dependent upon the specific disease process involved. Thus, this Erlenmeyer flask-shaped deformity is not specific for Gaucher’s disease. It can be seen with many other disorders especially marrow-packing disorders. The long bone radiographic changes in what is now known as Niemann-Pick’s disease are indistinguishable from those due to Gaucher’s disease. Figure 1 Erlenmeyer flask-shaped deformity shown in radiographs of patients with Gaucher’s disease and deformity of the distal femur. Reproduced from Fisher<xref ref-type="bibr" rid="ref33_4"> ⁴ </xref>. Das Rontgenbild der Knochen, besonders des Femur in der Diagnose des Morbus Gaucher. Fortschr. <italic>Geb. Rontgemtr., 1928</italic> <bold>,</bold> 37, 158–64, with permission https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003076568/34c29fd5-5662-4e8f-b58c-badd7fa5d724/content/fig33_1_B.jpg"/>