Split hand, unilateral is a rare, non-syndromic limb reduction defect, clinically and genetically heterogeneous, characterized by unilateral underdevelopment or absence of the central rays of the autopod, with absence of all, or just some, of the central phalanges and at least part of the associated metacarpal bones, yielding a cleft appearance of the hand. It is frequently associated with syndactyly and aplasia/hypoplasia of remaining digits and metacarpal bones. No other dysmorphic features are observed and development is appropriate for age. The disease is split hand, unilateral (MONDO_0017511).