LIMB DEFICIENCIES / REDUCTION DEFECTS

Limb deficiencies are isolated absence of an extremity or segment of an extremity. Limb deficiencies or congenital amputations constitute a group of disorders that are different from the osteochondrodysplasias.

ANATOMIC CLASSIFICATION

Deficiency	Description
Amelia	Absence or limb / limbs
Intercalcary
Meromelia	Missing part of a limb.
· Terminal transverse defect	Absence / hypoplasia of digits 1-5, 2-5 or 1-4
· Longitudinal defect	Absence / hypoplasia of the 5^th (and 4^th) digit
o Preaxial	Abnormality on the radial side
o Postaxial	Abnormality on the ulna side
· Preaxial and postaxial	Abnormalities of both the radial and ulna sides
· Central	Absence / hypoplasia of digit 3 alone, 2 +3, or 3 + 4
Mixed
Unclassifiable
McGuirk CK, Westgate N-M, Holmes LB. Limb deficiencies in newborn infants. Pediatrics 2001;108(4):108.

· Limb reduction defects were more common in the arms alone (70%), than the legs alone (18%) or both arms and legs (12%).

CLASSIFICATION ACCORDING TO CAUSE (1).

· Hereditary disorders (15%).

· Chromosomal abnormalities (trisomy 18, 4p-, 13q-) (6%).

· Specific malformation syndromes (5%).

· Familial phenotypes (unclassified) (4%).

· Vascular disruption (34%): Multiple reduction deficiencies,

1. Amniotic band syndrome.

2. Prostoglandin E1 analog misoprostol (asymmetric distribution, digit loss, constrictions and Syndactyly) (2).

3. Chorionic villous sampling (3-5).

4. Thalidomide exposure (symmetrical pattern of deficiency on the preaxial sides of both arms and legs) (6).

5. Ergotamine exposure (7).

6. Abnormal trauma to the abdomen (and placenta) (8).

· No recognizable cause (such as absent fibula).

Reduction deficiencies in the upper limb

• Isolated limb deficiencies of the upper extremity are usually isolated anomalies, however amputations of the leg, bilateral amputations or usually occur reduction of all four limbs usually occur in the context of a syndrome.

SYNDROMES ASSOCIATED WITH LIMB DEFICIENCIES

1. Amniotic band syndrome.
2. Aglossia adactylia syndrome (Hankart syndrome).
3. Moebius sequence.
4. Fibula aplasia-complex brachydactyly (Du Pan Syndrome).
5. CHILD Syndrome.
6. Splenogonadal fusion syndrome.
7. Robert's syndrome.
8. Adams-Oliver syndrome.
9. Phocomelia.
10. Grebe syndrome.
11. TAR syndrome.
12. Proximal focal femoral deficiency.
13. Femoral hypoplasia-unusual facies syndrome.
14. Poland’s anomaly.
15. Holt - Oram syndrome
16. Fanconi’s anemia
17. Maternal insulin dependent diabetes.

REFERENCES

1. McGuirk CK, Westgate N-M, Holmes LB. Limb deficiencies in newborn infants. Pediatrics 2001;108(4):108.
2. Gonzales CH, Marques-Dias MJ, Kim CAE et.al.Congenital abnormalities in Brazilian children associated with misoprostol misuse in the first trimester of pregnancy. Lancet 1998;351:1624-1627.
3. Firth HV, Boyd PA, Chamberlain P et.al. Severe limb abnormalities after chorionic villous sampling at 55-65days gestationb. Lancet 1991;337:762-763.
4. Firth HV. Chorionic villous sampling and limb deficiency:cause or coincidence? Prenat Diagn 1997;17:1313-1330.
5. Burton BK, Schulz CJ, Burd LI. Spectrum of limb reduction defects associated with chorionic villous sampling. Pediatrics 1993;91:989-993.
6. Kallen B, Rahmani TM-Z, Winberg J. Infants with congenital limb reduction registered in the Swedish Register of Congenital malformations. Teratology 1984;29:73-85.
7. Raymond GV. Teratogen update: ergot and ergotamine. Teratology 1995;51:344-347.
8. Viljoen DL. Porencephaly and transverse limb defects following severe maternal trauma in early pregnancy. Clin Dysmorphology 1995;4:75-78.
9. Marid BOD, Creizel A, Lenz W. Incidence at birth of different types of limb reduction abnormalities in Hungry 1975-1977. Hum Genet 1983;65:27.