Buy the Book PDA Download

Update Me E-mail alerts The Merck Manual Minute

Print This Topic Email This Topic

Congenital amputations are transverse or longitudinal limb deficiencies due to primary intrauterine growth inhibition or secondary intrauterine destruction of normal embryonic tissues.

Congenital amputations are missing or incomplete limbs at birth. Etiology is often unclear, but teratogenic agents (eg, thalidomide Some Trade Names
THALOMID
Click for Drug Monograph
) and amniotic bands are known causes.

In transverse deficiencies, all elements beyond a certain level are absent, and the limb resembles an amputation stump. For example, in proximal femoral focal deficiency, the proximal femur and acetabulum do not develop; degree of deficiency varies. Longitudinal deficiencies involve specific maldevelopments (eg, complete or partial absence of the radius, fibula, or tibia). They may result from a syndrome such as VACTERL (formerly VATER: vertebral anomalies, anal atresia, cardiac malformations, tracheoesophageal fistula, renal anomalies, and limb anomalies [eg, radial aplasia]). Infants with transverse or longitudinal limb deficiencies may also have hypoplastic or bifid bones, synostoses, duplications, dislocations, or other bony defects. One or more limbs may be affected, and type of defect may be different in each limb. CNS abnormalities are rare. X-rays are essential to determine which bones are involved.

Treatment consists mainly of prosthetic devices, which are most valuable for lower-limb deficiencies or for completely or almost completely absent upper limbs. If any activity in an arm or hand exists, no matter how great the malformation, functioning capacity must be thoroughly assessed before a prosthesis or operation is recommended. Therapeutic amputation of any limb or portion of a limb should be considered only after evaluating the functional and psychologic implications of the loss and when essential for fitting a prosthesis.

An upper-limb prosthesis should be designed to serve as many needs as possible so that the number of devices is kept to a minimum. Children use a prosthesis most successfully when it is fitted early and becomes an integral part of their body and body image during the developmental years. Devices used during infancy should be as simple and durable as possible; eg, a hook rather than a bioelectric arm. With effective orthopedic and ancillary support, most children with congenital amputations lead normal lives.

Last full review/revision November 2005

Content last modified November 2005