C syndrome is a rare multiple congenital anomaly/intellectual disability syndrome characterized by trigonocephaly and metopic suture synostosis, dysmorphic facial features, short neck, skeletal anomalies, and variable intellectual disability.

Digits that appear disproportionately short compared to the hand/foot. The word brachydactyly is used here to describe a series distinct patterns of shortened digits (brachydactyly types A-E). This is the sense used here.