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CHAPTER 30
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The Child with a Limb Deficiency
Terminal (T)
Transverse (-)
Longitudinal (/)
1. Amelia (absence of limb)
1. Complete paraxial hemimelia (complete absence of one of the
forearm or leg elements, and of the corresponding portion of the
hand or foot)—R, U, TI, or FI
a
2. Hemimelia (absence of forearm and hand or leg and foot)
2. Incomplete paraxial hemimelia (similar to the above, but part of
the defective element is present)—r, u, ti, or fi
a
3. Partial hemimelia (part of forearm or leg is present)
3. Partial adactylia (absence of one to four digits and their
metacarpals or metatarsals): 1, 2, 3, 4, or 5
4. Acheiria or apodia (absence of hand or foot)
4. Partial aphalangia (absence of one or more phalanges from one
to four digits): 1, 2, 3, 4, or 5
5. Complete adactylia (absence of all five digits and their
metacarpals or metatarsals)
6. Complete aphalangia (absence of one or more phalanges
from all five digits)
Intercalary (I)
Transverse (-)
Longitudinal (/)
1. Complete phocomelia (hand or foot attached directly to trunk)
1. Complete paraxial hemimelia (similar to corresponding terminal
defect but hand or foot is more or less complete)—R, U, TI, or FI
a
2. Proximal phocomelia (hand and forearm, or foot and leg,
attached directly to trunk)
2. Incomplete paraxial hemimelia (similar to corresponding terminal
defect but hand or foot is more or less complete)—r, u, ti, or fi
a
3. Distal phocomelia (hand or foot attached directly to arm or
thigh)
3. Partial adactylia (absence of all or part of a metacarpal or
metatarsal): 1 or 5
4. Partial aphalangia (absence of proximal or middle phalanx, or
both, from one or more digits):1, 2, 3, 4, or 5
-, transverse; /, longitudinal; 1, 2, 3, 4, or 5 denotes the digital ray involved; FI or fi, fibular; I, intercalary; R or r, radial; T, terminal; TI or ti, tibial; U or u, ulnar.
A line below a numeral denotes upper limb involvement; for example, T-2 represents terminal transverse hemimelia of the upper limb. A line above a numeral denotes
lower limb involvement; for example, I-1 represents intercalary transverse complete phocomelia of the lower limb.
a
In capital letters when the paraxial hemimelia is complete, in small letters when the defect is incomplete.
From Frantz C, O’Rahilly R. Congenital skeletal limb deficiencies. J Bone Joint Surg Am 1961;43:1202, with permission.
TABLE 30.1
Classification of Congenital Skeletal Limb Deficiencies
transverse amputation. The previously developed limb has
actually been recovered at the time of birth, indicating the
mechanism (12). Evidence suggests that most amniotic bands
cause deficiency within the first month postconception, based
on the fact that limbs and organs commonly affected together
are located in close proximity in the embryonic, but not fetal,
stage of development (13). Most children with amniotic band
syndrome additionally have either craniofacial abnormalities
or other evidence of band formation.
Modern genetics has shown that the development of
the limb is a complex phenomenon that requires the precise
interaction of a large number of genes and their effects, which
are described in Chapter 1 and other review articles (14, 15).
Many of the proteins and growth factors that participate in
this complex interaction have been elucidated (16). Genetic
causes of limb deficiency can include chromosomal abnor-
malities (trisomy 18 and radial longitudinal deficiency), as
well as single-gene defects, which result in deficiencies that
closely follow Mendelian genetic transmission patterns (tibial
deficiency, cleft hand and foot, radial longitudinal deficiency).
Even the so-called sporadic deficiencies are more common in
families with a history of similar deficiencies. A recent study
from the Medical Birth Registry of Norway showed that chil-
dren born to a mother with a limb deficiency had a relative risk
of 5.6% of having the same defect as the mother (17). This is
similar to the relative risk of clubfoot. These facts carry conse-
quences for genetic counseling. Understanding the cause of the
deficiency is important to the resolving of the guilt that par-
ents will initially feel. The possibility of a transmissible defect
is certainly something both they and their affected offspring
will also need to know. For the physician, knowing the exis-
tence of medical comorbidities and the natural history of the
syndrome is necessary for the care of the child.
The disruption of the subclavian artery and its blood sup-
ply to the tissues explains the overlap of many of the common
orthopaedic conditions seen, for example, Poland syndrome,
Klippel-Feil syndrome, Mobius syndrome, Sprengel deformity,
and transverse limb deficiencies. There are several possible
