Examining the number and appearance of the fingers and thumbs may reveal syndactyly or webbing, both common findings. Hypoplasia of any element of the hand, wrist, or forearm should be noted. Poland syndrome involves brachysyndactyly of the fingers (short, webbed fingers) and hypoplasia, or maldevelopment of the chest wall on the same side. More significant deformities, such as radial club hand, show characteristic hypoplasia, or absence of the radial structures of the forearm and the hand, and can be associated with a short, bowed forearm and aplasia, or hypoplasia of the thumb. A "floating thumb" or "pouce floutant" is a small thumb with no bony attachment to the rest of the hand. Hypoplasia of the ulna and the ulnar aspect of the hand is more rare than a radial club hand. Madelung's deformity is characterized by lateral bowing of the radius with subluxation of the distal ulna, with a normally developed hand. Limited range of motion of the wrist with fixed flexed fingers and thumbs in adduction could be indicative of a neuromuscular condition, such as cerebral palsy or arthrogryposis. Symphalangism, a rare finding, is failure of joint development, with the fingers fixed in some degree of flexion. Babies' thumbs are sometimes clasped. Lack of passive or active extension of the thumbs could be a sign of either a congenital trigger thumb or clasped thumb in which there is some agenesis of the extensor muscle. Congenital amputation of fingers, particularly the fingertips, can be a presentation of congenital constriction band syndrome. Similar findings in the toes can be helpful in making the diagnosis.
J Pediatr Health Care. 2003;17(1) © 2003 Mosby, Inc.
Cite this: Pediatric Orthopedic Physical Examination of the Infant: A 5-Minute Assessment - Medscape - Jan 01, 2003.