Any non-syndromic synpolydactyly in which the cause of the disease is a mutation in the HOXD13 gene. The disease is synpolydactyly type 1 (Monarch Disease Ontology entry MONDO_0008513). Also known as: HOXD13 non-syndromic synpolydactyly, SD2, Vordingborg type, SD2a, SPD, Vordingborg type, SPD1, non-syndromic synpolydactyly caused by mutation in HOXD13, synpolydactyly, Vordingborg type.