syndactyly

Syndactyly (plural: syndactylies) refers to a congenital fusion of two or more digits. It may be confined to soft tissue (soft tissue syndactyly/simple syndactyly) or may involve bone (bony syndactyly/complex syndactyly).

Epidemiology

The overall estimated incidence is at ~1 per 2,500 to 5,000 live births . There may be a greater male predilection.

Pathology

There is a very wide spectrum of syndactyly ranging from partial to complete.

Associations

Syndactyly can occur as an isolated phenomenon or can be associated with numerous other entities. Isolated cases can be either sporadic or familial.

Aneuploidic syndromic

• triploidy: tend to affect the 3 and 4 digits of the hands

Non-aneuploidic syndromic

• acrocephalosyndactylies
  • type I: Apert syndrome
  • type II: Crouzon syndrome
  • type III: Saethre-Chotzen syndrome
  • type V: Pfeiffer syndrome
• acrocephalopolysyndactylies
  • type I: Noack syndrome
  • type II: Carpenter syndrome: typically gives soft tissue syndactyly
  • type III: Sakati-Nyhan syndrome
  • type IV: Goodman syndrome
• amniotic band syndrome
• Fraser syndrome / cryptophthalmos syndrome
• Gorlin syndrome
• Greig cephalopolysyndactyly syndrome 
• macrodystrophia lipomatosa
• Pallister-Hall syndrome
• Poland syndrome
• proximal radioulnar synostoses: Cenani Lenz syndactyly
• prune belly syndrome
• Roberts syndrome
• VACTERL association
• Down syndrome 
• neurofibromatosis type 1

Non syndromic

• isolated polydactyly, a.k.a. polysyndactyly
• isolated brachydactyly, a.k.a. brachysyndactyly
• isolated ectrodactyly

Distribution

As a whole the 2 and 3digits tend to be most frequently associated . May involve the toes more than fingers.

Radiographic features

Plain radiograph

Postnatally the type and degree of bony syndactyly can be easily diagnosed on plain film.

Antenatal ultrasound

Often difficult to diagnose on ultrasound (especially with soft tissue syndactyly). The diagnosis may be suggested if the digits appear to constantly move together . The fingers may appear constantly deformed with complex syndactyly .

Treatment and prognosis

The overall prognosis can be extremely variable depending on the presence of other associated anomalies.

History and etymology

The term syndactyly is derived from the Greek words syn meaning together and daktulos meaning fingers.

See also

• symphalangism

Siehe auch:

• Polydaktylie
• Amniotisches-Band-Syndrom
• Brachydaktylie
• Gorlin-Goltz-Syndrom
• VACTERL-Assoziation
• macrodystrophia lipomatosa
• Apert-Syndrom
• Roberts-Syndrom
• Poland-Syndrom
• prune belly syndrome
• Carpenter syndrome
• Crouzon-Syndrom
• angeborene Handfehlbildungen
• Ektrodaktylie
• Triploidie
• acrocephalopolysyndactyly
• Tetradaktylie
• Pallister-Hall-Syndrom
• Noack syndrome
• Goodman syndrome
• Polysyndaktylie
• Sakati Nyhan syndrome
• Fraser-Syndrom
• Cenani Lenz syndactyly
• Greig-Syndrom

und weiter:

• cyllosoma
• Mesomelie
• Meckel-Syndrom
• fetal conditions associated with maternal diabetes
• Tibiale Hemimelie
• acrocephalosyndactyly
• De-Grouchy-Syndrom Typ 2
• Mesomele Dysplasie
• dysencephalia spanchnocystica
• Saethre-Chotzen-Syndrom
• Smith-Lemli-Opitz-Syndrom
• kongenitale Anomalien der Finger
• acrocephalopolysyndactyly type II
• Eaton-McKusick-Syndrom
• acrofacial dyostosis
• Oligodaktylie
• ectrodactyly-ectrodermal dysplasia-clefting syndrome
• 7-dehydrocholesterol reductase deficiency
• Patterson-Stevenson-Fontaine-Syndrom
• Pseudoaminopterin-Syndrom
• high-head syndrome
• kongenitale Anomalien der Zehen
• Symbrachydaktylie
• Oligosyndaktylie
• central polysyndactyly
• Dubowitz-Syndrom