A wide range of hand deformities can occur during the earliest stages of fetal development. While the causes of these congenital anomalies are not understood, advanced treatment options are available for children who require them to function well in school and at play. Importantly, not all kids need surgical correction of their deformity but can learn to do all the things they want to do with certain adaptations, counseling to help them handle teasing, and occupational therapy. Congenital hand deformities include extra or missing fingers, fingers that are joined together (see “webbed fingers”), and missing or abnormally formed bones in the hand or arm. Your physician will be able to recommend prosthetic devices that may help your child participate in sports or other activities, and can counsel you on surgical options to improve the functionality and/or appearance of a child’s hand.