Possible Achondroplastic Dwarf Skull from Montevideo, Uruguay.

Achondroplasia (chondrodystrophia) is an autosomal dominant inherited disorder affecting approximately 1 in 26,000 live births and is the most common cause of dwarfism in humans. Disproportionate short stature and a suite of craniofacial characteristics typify achondroplasia. The literature available for differential diagnosis of the disorder relies primarily on the postcranial skeleton. In this paper, a possible case of achondroplasia is presented. The cranium presents a unique suite of cranial and craniofacial dysmorphologies. The lack of postcranial remains does not permit their use in the analysis. To make a differential diagnosis and to quantify the observed craniofacial dysmorphologies, craniometric data are compared to modern clinical literature and to craniometric data from known achondroplastic dwarfs. Thin-plate spline analysis is integrated to quantify the differences in degree and magnitude of shape change. This manuscript demonstrates an appropriate methodology for identifying achondroplasia from the cranial skeleton alone.