ectrodactyly (clefting) syndromes
description
the term ectrodactyly means ‘aborted fingers’ and has been applied to a wide range of abnormalities. this section will focus on those lesions that are mainly central in location and result in either a ‘v’ or ‘u’ shaped defect, with or without compromise of the nearby digits. there can be associated syndactyly, oligodactyly, polydactyly, hypoplasia or absence of some phalanges or even compromise of other long bones. the metacarpals and metatarsals are usually affected, but mild forms may only involve soft tissues or just the phalanges. in extreme cases only a single digit remains. it can be present in all four extremities or be localised to the hands or feet. the defect can be isolated or may be part of a syndrome. ‘v’ shaped defects tend to be bilateral while ‘u’ shaped defects are often unilateral. the latter usually occurs as a sporadic event and has no known genetic basis. it has been postulated that this type of defect may be the result of a vascular disruption to the embryonic blood supply of the developing hand. chromosomal analysis is recommended, since various abnormalities have been documented in several cases.
diagnosis
hand and feet abnormalities range from hypoplastic nails to polydactyly, syndactyly and lobster claw-deformity. the carpal, tarsal, metacarpal or metatarsal bones can be dysplastic or absent. ‘v’ or ‘u’ shaped defects can be encountered. absent or abnormal digit posture is very common. the defects are not always bilaterally symmetric.
differential diagnosis
isolated (familial) split hand/split foot (sh/sf) displays no other abnormalities. sh/sf with absent long bones typically presents with sh and aplasia of the tibia, or sf with ulnar aplasia. when the sh occurs in the same limb as the absent bone the differential diagnosis has to be made with radial and ulnar ray defects. the sf with triphalangeal thumb is inherited in an autosomal dominant fashion. the sh/sf with central polydactyly is usually an isolated, sporadic condition. the acrorenal syndrome affects mainly females and feature sh/sf with genitourinary malformations and micrognathia. the eec syndrome is characterized by ectrodactyly, ectodermal defects and facial clefting (see separate text under this heading). fontaine syndrome (mandibulofacial dysostosis) is an autosomal dominant disorder characterised by ectrodactyly and syndactyly of the foot (sf), with cleft palate and microretrognathia. the karsch-neugebauer syndrome is characterised by the association of sh/sf and congenital nystagmus. chromosomal studies should be performed since many abnormalities have been reported in patients with ectrodactyly.
sonographic features
lobster-claw deformity of hands and feet
polydactyly, syndactyly, clinodactyly
different patterns of absence or hypoplasia of some metacarpals or metatarsals
other findings depending on the specific syndrome encountered
associated syndromes
- acro-renal mandibular
- adams-oliver
- amniotic bands/ rupture sequence
- ectrodactyly-ectodermal dysplasia-clefting (eec)
- tibial hypoplasia/ aplasia ectrodactyly
references
- goldberg m in: the dysmorphic child. an orthopedic perspective raven press p 344-350
- taybi h, lachman rs in: radiology of syndromes, metabolic disorders and skeletal dysplasias mosby publishing yearbook: 4th ed
akita s, kuratomi h, abe k, harada n, mukae n, niikawa n eec syndrome in a girl with paracentric inversion clin dysmorphol 2: 62-67 - aneren g, andersson t, lindgren pg, kjartansson s ectrodactyly-ectodermal dysplasia-clefting syndrome (eec): the clinical variation and prenatal diagnosis clin genet 40: 257-262
- bronshtein m, gershoni-baruch r prenatal transvaginal diagnosis of the ectrodactyly, ectodermal dysplasia, cleft palate (eec) syndrome prenat diag 13: 519-522
- fukushima y, ohashi h, hasegawa t the breakpoints of the eec syndrome (ectrodactyly, ectodermal dysplasia and cleft lip/palate) confirmed to 7q11.21 and 9p12 by fluorescence in situ hybridization clin genet 44: 50
- hasegawa t, hasegawa y, asamura s, nagai t, tsuchiya y, ninomiya m, fukushima y eec syndrome (ectrodactyly, ectodermal dysplasia and cleft lip/palate) with a balanced reciprocal translocation between 7q11.21and 9p12 (or 7p11.2 and 9q12) in three generatio clin genet 40: 202-206
- jamehdor m, beligere n, kaye ci, pruzansky s, rosenthal i incomplete eec syndrome in a patient with mosaic monosomy 21 cleft palate j 15: 390-397
- kohler r, sousa p, santos jorge c prenatal diagnosis of the ectrodactyly, ectodermal dysplasia, cleft palate (eec) syndrome j.ultrasound med 8: 337-339
- qumsiyeh mb eec syndrome (ectrodactyly, ectodermal dysplasia and cleft lip/palate) is on 7p11.2 q21.3 clin genet 42: 101
- rodini eso, richieri-cost a eec syndrome: report of 20 new patients, clinical and genetic considerations am j med genet 37: 42-53
viljoen dl, smart r split-foot anomaly, microphtalmia, cleft-lip and cleft-palate, and mental retardation associated with chromosome 6;13 translocation clin dysmorphol 2: 274-277