Tarsal-carpal coalition syndrome is characterised by fusion of the carpals, tarsals, and phalanges.Last update: September 2007
Less than 10 affected families have been described so far.
At birth, patients present with stiffness of the proximal interphalangeal joint of the fifth digit, with or without bony synostosis. Proximo-distal progression leads to involvement of the fourth, third and then the second digits. Other anomalies include brachydactyly, humeroradial synostoses and, in some cases, short stature.
Causative mutations in the NOG gene have recently been identified, showing that this syndrome is an allelic variant of symphalangism.
Tarsal-carpal coalition syndrome can be distinguished from multiple synostoses syndrome and proximal symphalangism (see these terms) by the absence of hearing loss.
Transmission is autosomal dominant.