"Duplicate calcaneus": a rare developmental defect observed in several skeletal dysplasias
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Published on: March 15, 2015
V Cormier-Daire1, R Savarirayan, S Unger
1Cedars-Sinai Medical Center and UCLA School of Medicine, Los Angeles, California 90048, USA.
Abstract:
Duplication of the calcaneus is a rarely observed radiographic finding that probably results from delayed coalescence of two primary calcaneal centers of ossification. We performed a review of 2,500 computerized cases of skeletal dysplasias and syndromes with bone involvement in the International Skeletal Dysplasia Registry, searching for those cases in which a duplicate calcaneus had been recorded. We found that it was a non-random feature of three skeletal dysplasias and groups comprising thanatophoric dysplasia and the chondrodysplasia punctata and short rib (polydactyly) groups. We conclude that duplication of the calcaneus should be considered a consistent feature of these entities and may reflect a more generalized developmental defect.
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