CHAPTER 30
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The Child with a Limb Deficiency
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Epidemiology and Etiology
Pediatric limb deficiency is uncommonly encountered by
most pediatric orthopaedic surgeons. Depending on which
global location is being considered, either congenital or
acquired deficiencies may predominate. Congenital defi-
ciencies are more common in developed nations (3), while
traumatic amputations can predominate in lesser developed
nations (4). Tumors are an uncommon but important cause
of limb deficiency in children in all locations. Because limb
deficiency is uncommon, patients are often treated in tertiary
organized programs that have the experience and resources to
treat these patients.
Depending on the methods used, the calculated incidence
may vary widely, from 6 per 10,000 in British Columbia (5)
to 310 per 10,000 in Tayside, Scotland (6). In a survey of
European countries participating in the International Clearing
House for Birth Defects Monitoring Programme, the inci-
dence was between 3.1 and 7.9 per 10,000 (7). Statistics such
as these are more accurately determined by well-collected birth
registries and less accurately determined by surveys from pros-
thetic clinic medical records, which can overestimate incidence
if the clinic is a tertiary referral center.
Fibular deficiency is the most common cause of long
bone congenital limb deficiency, when considering that fibu-
lar deficiency often accompanies femoral deficiency. Femoral
deficiencies are the next-most common, with an incidence
between 1 in 50,000 and 1 in 200,000 live births. Femoral
deficiencies include the spectrum of the congenital short
femur with a stable hip joint and a knee without significant
contracture to proximal femoral focal deficiency (PFFD). The
prevalence of tibial deficiencies is far less than either fibular or
femoral deficiencies and is reported to be approximately one
per million live births.
The incidence of all upper extremity amputations is not
precisely known but is thought to be more than lower extremity
amputations and more often congenital and bilateral than
acquired (8, 9). The most common congenital upper extremity
amputation is by far the transverse forearm (below-elbow)
amputation, with radial longitudinal deficiency being the next-
most common. In reality, few pediatric orthopaedic surgeons,
other than those working in a limb-deficiency program, will
have much experience with these amputations. Although the
physician should strive to understand the cause of a congenital
amputation in all cases, most of the time no identifiable cause
exists. Limb deficiencies can be caused in several ways, such as
by environmental factors, genetic disorders, vascular anomalies
(such as “the subclavian artery supply disruption sequence”),
(10) and amniotic bands.
The oldest and most commonly held etiology for congen-
ital amputation in the past was the mechanical amputation of
limbs by amniotic bands, or Streeter dysplasia. Streeter postu-
lated that the bands caused an intrinsic defect in the growth of
the fetal limb (11). There is, however, evidence that amniotic
bands can form a constriction around the developing limb that
interferes with the growth of the limb. The resulting constric-
tion can lead to any degree of damage, from a constriction
band around a limb that is otherwise normal to a complete
Amelia
Incomplete
hemimelia
Incomplete
phocomelia
Radial
hemimelia
Radial
hemimelia
Tibular
hemimelia
Complete
hemimelia
Ulnar
hemimelia
Fibular
hemimelia
Fibular
hemimelia
Complete
phocomelia
Ulnar
hemimelia
Congenital skeletal limb deficiencies
Terminal deficiencies
laixaraP
esrevsnarT
There are no unaffected parts distal to
and in line with the deficient portion
Middle portion of limb is deficient but
proximal and distal portions are present
Defect extends transversely
across the entire width of limb
Only the preaxial or postaxial
portion of limb is absent
laixaraP
lartneC
Entire central portion of limb
absent with foreshortening
Segmental absence of preaxial
or postaxial limb segments
intact proximal and distal
Intercalary deficiencies
FIGURE 30-1.
Diagrammatic representation of the Frantz and O’Rahilly classification of congenital limb deficiencies.
(From Frantz C, O’Rahilly R. Congenital skeletal limb deficiencies. J Bone Joint Surg Am 1961;43:1202, with permission.)
