Obstetric US: watch the fetal hands.
Hand anomalies are difficult to diagnose and are often overlooked during prenatal ultrasonography (US). The spectrum of malformations varies from subtle finger deformities to the complete amputation of limbs. Malformations of the hand can be classified, according to the predominant anomaly, among the following categories: alignment abnormalities (clenched hand, camptodactyly, clinodactyly, hypokinesia, clubhand, phocomelia), thumb anomalies, abnormal size (macrodactyly, trident hand), abnormal echogenicity (abnormal calcifications), abnormal number (polydactyly, syndactyly, ectrodactyly), and constriction band sequence. A fetal hand anomaly has important diagnostic and prognostic implications as well as functional consequences. Malformation may be isolated but often is associated with a syndrome or karyotype anomaly. Classification and characterization of the anomaly help to narrow the differential diagnosis: Some malformations (clenched hand, hitchhiker thumb) are highly suggestive of a specific diagnosis. The detection of a fetal hand malformation warrants a complete work-up, including complete fetal and cardiac US examinations, as well as genetic counseling to determine whether familial inquiry and karyotype analysis are necessary.
Rypens
Françoise
F
Department of Radiology, Hôpital Ste-Justine and Université de Montréal, 3175 Côte Ste-Catherine, Montreal, Quebec, Canada H3T 1C5. francoise_rypens@ssss.gouv.qc.ca
Dubois
Josée
J
Garel
Laurent
L
Fournet
Jean-Christophe
JC
Michaud
Jacques L
JL
Grignon
Andrée
A
D006228:Hand Deformities, Congenital / Q000000981:diagnostic imaging*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007231:Infant, Newborn; D009774:Obstetrics / Q000379:methods*; D017410:Practice Guidelines as Topic; D010818:Practice Patterns, Physicians'; D016216:Ultrasonography, Prenatal / Q000379:methods*