The Thumb in the Congenital Malformation Syndromes

Abstract

Anomalies of the thumb which may be associated with congenital malformation syndromes include enlargement, duplication, and hypoplasia. The thumb may also be absent, have abnormal ossification centers, or be abnormal in position. The normative values of the ratio of the lengths of each bone to the others as well as to the second metacarpal are tabulated. These ratios are useful for objective evaluation of relative lengthening or shortening of the thumb bones. The radiographic appearances of the thumb in various syndromes are described and illustrated.