ectrodactyly

Ectrodactyly (also known as a split hand-split foot malformation, cleft hand or lobster claw hand) is a skeletal anomaly predominantly affecting the hands (although the feet can also be affected). The condition has a highly variable severity.

Epidemiology

The estimated incidence is at ~ 1 in 90,000-150,000 births.

Pathology

It results from a longitudinal deficiency in central digits where the mechanism is thought to be a failure of the median apical ectodermal ridge in the developing limb bud.

Genetics

The most common mode of transmission is as an autosomal dominant trait, although autosomal recessive and X-linked modes of transmission also have been described.

Associations

• syndromic
  • EEC syndrome (ectrodactyly-ectrodermal dysplasia-clefting syndrome)
    • ectrodactyly
    • ectodermal dysplasia
    • cleft lip or palate
  • Karsch-Neugebauer syndrome
  • Roberts syndrome
• non syndromic
  • syndactyly, aplasia, or hypoplasia of the residual phalanges/metacarpals
  • sensorineural hearing loss

Radiographic features

Plain film

• there is a deficiency or absence of one or more central digits of the hand +/- feet
• characterized by a deep V- or U-shaped central bony defect

Differential diagnosis

General differential considerations include

• amniotic band sequence: usually unilateral and may be not symmetrical

Siehe auch:

• Amniotisches-Band-Syndrom
• Syndaktylie
• Oligodaktylie
• EEM-Syndrom
• Polysyndaktylie
• Gollop-Wolfgang-Syndrom
• Tibia-Aplasie-Ektrodaktylie-Syndrom
• Karsch-Neugebauer-Syndrom
• Femur-Bifurkation
• ADULT-Syndrom

und weiter:

• sandal gap deformity
• Akrorenales Syndrom
• ectrodactyly-ectrodermal dysplasia-clefting syndrome
• Rosselli-Gulienetti-Syndrom
• Monodaktylie