Tetrapolydactyly: a rare presentation and review of the literature

Abstract

Polydactyly is a common congenital anomaly characterized by the presence of extra digits on the hands and/or feet, potentially involving all four limbs simultaneously. The terminology used to describe polydactyly involving all four limbs varies in the literature, with terms such as “tetrapolydactyly,” “polydactyly 24,” and “hexadactyly of all limbs” being used interchangeably. We encountered a case of tetrapolydactyly in a female neonate with postaxial polydactyly involving all four limbs. Our patient had an extra digit on the ulnar side with a bony component on the left hand and a similar extra digit without a bony articulation at the base of the right hand. The right foot showed postaxial polydactyly, and the left foot exhibited both preaxial polysyndactyly and postaxial polydactyly. A review of the literature shows that this combination of anomalies is extremely rare. A family history is present in approximately 30% of cases, asymmetric patterns are rarer than symmetric patterns, and heptadactyly is particularly uncommon. This report summarizes the information on tetrapolydactyly in the literature and discusses the clinical implications as well as management strategies.