Tarsoid and Gonoid malformations of upper limbs

A bizarre and apparently hiherto unknown malformation complex mainly affecting the upper limbs was observed in a boy who underwent radiologic examination at 6 and 15 years of age. The most conspicuous abnormalities are represented by knee-like elbows and carpal elements resembling tarsals, additionally there was also marked overgrowth of the tarsal bones. The combination of these virtually unique malformations might suggest the existence of some early morphogenetic factor responsible for differentiation of the lower limbs and capable create ectopic elements of the lower limbs by conversion of the homologous parts of the upper limbs.