Absence or hypoplasia of the radii and thumbs usually occurs as an isolated and presumably nonhereditary malformation.1,2 Among those for which a genetic basis has been proven, there are at least three different types of hereditary absence of radii1 as well as several disorders with absence or hypoplasia of the radii a feature of a hereditary syndrome of multiple malformations.3-15 We have evaluated a boy who appears to have a previously unreported pattern of upper limb deformities and minor craniofacial anomalies. The fact that his mother has milder, but similar deformities, suggests the disorder is hereditary.
CASE HISTORIES
The propositus (A.B.) was born in 1966. His birth weight was 2.6 kg and length 46 cm. Because her two previous pregnancies had ended in spontaneous abortions at four and six weeks' gestation, his mother was given four intramuscular injections of hormone preparations. The medication was hydroxyprogestrone caproate (Delalutin), 250 mg, which was given 47,61,76 and 90 days after her last menstrual period. In addition, she took a medication (Bonadoxin, each tablet containing 25 mg of meclizine hydrochloride and 50 mg of pyridoxine htydrochloride) for nausea for three weeks and a multivitamin preparation throughout the pregnancy. At birth the propositus was noted to have no thumbs, three fingers on his left hand and four on his right hand, flexion deformities and ulnar deviation of his fingers and by radiography shortening of both radii without radial deviation of each forearm. Full-body radiographs revealed no other abnormalities. At four years he underwent surgical removal of the distal portion of his right index finger because of the severe flexion contracture and ulnar deviation which interfered with the function of the adjacent finger.
The Dynamic Thumb-in-Palm Pattern in Children with Spastic Cerebral Palsy and Its Effects on Upper Limb Function