A very rare congenital limb malformation with characteristics of postaxial syndactyly of hands and feet, associated with metacarpal and metatarsal fusion of fourth and fifth digits. So far, less than ten reports have been described in the literature. Soft tissue syndactyly (involving the third and fourth fingers and the second and third toes) may be present. The locus associated with SD5 maps to 2q31-q32. Mutations in the HOXD13 gene may be causative. The condition is inherited as an autosomal dominant trait.

Arboleda-Tham syndrome (ARTHS) is an autosomal dominant disorder with the core features of impaired intellectual development, speech delay, microcephaly, cardiac anomalies, and gastrointestinal complications (summary by Kennedy et al., 2019).