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It is a rare disease with approximately 150 cases reported worldwide. The exact prevalence is unknown, but the syndrome seems more common among the Amish community.

Prenatal abnormalities (that may be detected by ultrasound examination) include narrow thorax, shortening of long bones, hexadactyly and cardiac defects. After birth, cardinal features are short stature, short ribs, polydactyly, and dysplastic fingernails and teeth. Heart defects, especially abnormalities of atrial septation, occur in about 60% of cases. Cognitive and motor development is normal.

Mutations of the EVC and EVC2 genes, located in a head to head configuration on chromosome 4p16, have been identified as causative.

EVC belongs to the short rib-polydactyly group (SRP) and these SRPs, especially type III (Verma-Naumoff syndrome), are discussed in the prenatal differential diagnosis. Postnatally, the essential differential diagnoses include Jeune dystrophy, McKusick-Kaufman syndrome and Weyers syndrome.

This rare condition is inherited as an autosomal recessive trait with variable expression.

The management of EVC is multidisciplinary. Management during the neonatal period is mostly symptomatic, involving treatment of the respiratory distress due to narrow chest and heart failure. Orthopedic follow-up is required to manage the bones deformities. Professional dental care should be considered for management of the oral manifestations.

Prognosis is linked to the respiratory difficulties in the first months of life due to thoracic narrowness and possible heart defects. Prognosis of the final body height is difficult to predict.