Angel-shaped phalango-epiphyseal dysplasia (ASPED): identification of a new genetic bone marker.

ABSTRACT

We describe a "new" mild malformation of the phalanx, which we call the "angel-shaped phalanx" (ASP) because of its resemblance to the little angels used for the decoration of Christmas trees. A particular middle phalangeal type of ASPs is found in a distinct variety of multiple epiphyseal dysplasia with marked retardation of bone age and severe coxarthrosis in adult life, previously reported as "hereditary peripheral dysostosis" [Bachman, 1967 Proc R Soc Med 6021-22; Giedion, 1969 Fortschr Rontgenstr 110507-524]. However, these authors overlooked the unique configuration of the middle phalanges. We renamed the condition "angel-shaped phalango-epiphyseal dysplasia (ASPED)", which may be transmitted in an autosomal-dominant manner. Six new patients are added, bringing the total to nine patients (two families and two isolated patients). ASPs were seen in five of six children. The ASPs grew into inconspicuous brachydactyly after physeal closure (3/3). The most important additional radiological finding is late and dysplastic development of both femoral heads (5/5), leading to Perthes-like and osteoarthritic changes and severe hip pain in the early thirties (2/2 adults, having reached this age). The marked retardation of carpal bone age may lead to unnecessary clinical evaluation for endocrine disorders. Less frequent clinical manifestations of ASPED are hyperextensibility of the interphalangeal joints (7/9) and hypodontia (4/7). Other types of ASPs are observed in brachyphalangy type C, spondylo-megepiphyseal-metaphyseal dysplasia, and other conditions. The concept of mild bone abnormalities as specific markers for genetic disease, as with cone-shaped epiphyses and now evident in ASPED, may also be useful for ASPs in general.