Syndactyly is a condition wherein two or more digits are fused together. It occurs normally in some mammals, such as the siamang and diprotodontia, but is an unusual condition in humans. [Source: Wikipedia ]

Soft tissue union, with or without osseous union, between adjacent digits
Syndactyly Malik-Percin type
Syndactyly type 1
Syndactyly type 5
Syndactyly with craniosynostosis
May Cause
Broad distal phalanx of thumb
Delta phalanx
May Be Caused by
Acrocephalosyndactyly Pfeiffer type
Acrocephalosyndactyly Saethre-Chotzen type
Apert syndrome
Carpenter syndrome
Fanconi anemia
Holt-Oram syndrome
Isolated anomaly
Oculo-dento-osseous dysplasia
TAR syndrome
Thermal injury
Trisomy 13
Trisomy 18
Aarskog syndrome
Acro-cranio-facial dysostosis
Acro-fronto-facio-nasal dysostosis
Acrorenal syndrome
Aminopterin fetopathy
Amniotic band syndrome
Anonychia-ectrodactyly syndrome
Aphalangy - syndactyly - microcephaly
Aplasia cutis congenita
Bardet-Biedl syndrome
Blepharophimosis - ptosis - esotropia - syndactyly - short stature
Bloom syndrome
Brachmann-de Lange syndrome
Brachydactyly type A2
Brachydactyly type B
Cenani-Lenz like syndactyly
Cenani-Lenz type syndactyly
Chondrodysplasia punctata
Cloverleaf skull deformity
Cohen syndrome
Craniodigital syndrome of Scott
Craniofrontonasal dysplasia
Craniosynostosis Philadelphia type
Curry-Jones syndrome
DOOR syndrome
Dubowitz syndrome
Ectodermal dysplasia - syndactyly syndrome
EEC syndrome
Ehlers-Danlos syndrome
Ellis-van Creveld syndrome
Epidermolysis bullosa
Epidermolysis bullosa dystrophica
Eyebrow duplication - syndactyly
F syndrome
Familial brachydactyly A2
Familial brachydactyly B
Familial crossed polysyndactyly
Familial syndactyly type 3
Familial syndactyly with metacarpal and metatarsal fusion
Feingold syndrome
Fetal hydantoin syndrome
FG syndrome
Fibrodysplasia ossificans progressiva
Fibular aplasia-ectrodactyly
Filippi syndrome
Fraser syndrome
Fuhrmann syndrome
Goltz syndrome
Gorlin syndrome
Greig cephalopolysyndactyly syndrome
Hallermann-Streiff syndrome
Heart-hand syndrome type 3
Herrmann-Opitz syndrome
Hypomelanosis of Ito
Incontinentia pigmenti
Kaufman-McKusick syndrome
KBG syndrome
Lacrimo-auriculo-dento-digital syndrome
Laurence-Moon syndrome
Laurin-Sandrow syndrome
Lenz microphthalmia syndrome
Macrocephaly-cutis marmorata telangiectasia syndrome
Meckel syndrome
Mesomelic dysplasia Werner type
Möbius syndrome
Multiple synostosis syndrome
Nager acrofacial dysostosis
Naguib-Richieri-Costa syndrome
Neu-Laxova syndrome
Opitz trigonocephaly syndrome
Orofaciodigital syndrome type 1
Orofaciodigital syndrome type 2
Oromandibular-limb hypogenesis syndrome
Otopalatodigital syndrome type 1
Otopalatodigital syndrome type 2
Pallister-Hall syndrome
Pfeiffer syndrome
Poland syndrome
Polysyndactyly and congenital heart disease
Popliteal pterygium syndrome
Postaxial acrofacial dysostosis syndrome Miller type
Prader-Willi syndrome
Pterygium syndrome
Ptosis - syndactyly - learning difficulties
Roberts syndrome
Robin sequence
Robinow syndrome
Rothmund-Thomson syndrome
Rubinstein-Taybi syndrome
Saethre-Chotzen syndrome
Sakati syndrome
Short rib-polydactyly syndrome
Short rib-polydactyly syndrome type 1
Silver-Russell syndrome
Smith-Lemli-Opitz syndrome
Sorsby syndrome
Spondylocostal dysostosis
Summitt syndrome
Syndactyly - camptodactyly and clinodactyly of fifth fingers - bifid toes
Syndactyly - telecanthus - anogenital and renal malformations
Tel Hashomer camptodactyly syndrome
Tetrapolysyndactyly and postaxial polydactyly
Trichorhinophalangeal dysplasia type 1
Trichorhinophalangeal dysplasia type 2
Trisomy 21
Waardenburg anophthalmia syndrome