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parents' DNA tested for OI in anticipation of it being
raised by the defense at trial, even though there were
no clinical features other than multiple fractures to sug-
gest the possibility of this diagnosis. The test results
indicated that the baby and her father had a variant in
the COL1A2 gene that had been briefly described in
only one report in a patient listed as having “OI type
1.”
5
That report did not define the variant as disease-
causing for OI type 1. And, in spite of the fact that there
was no other medical history or clinical findings for
the father or the baby that suggested the variant was
disease-causing in this case, the defense at trial was that
the baby's injuries were the result of minor trauma and
OI type 1. The jury apparently rejected this theory and
convicted the defendant of Manslaughter in the Second
Degree. In some cases, however, it is difficult for medi-
cal providers to distinguish inflicted fractures from acci-
dental fractures in patients already diagnosed with OI.
In 1996, Steiner et al. sought to determine whether,
among children suspected of having been abused,
analysis of collagen synthesized by dermal fibro-
blasts could identify children with OI.
6
In 48 children,
fibroblast cell cultures studied for collagen synthesis
revealed that six of the children had biochemical evi-
dence of OI. It is important to note that in five of the
six children with abnormal results on collagen studies,
clinical signs of OI in addition to fractures were present
on examination by a physician familiar with the condi-
tion. In those five cases, the diagnosis of OI had been
strongly suspected on physical examination. Thus, the
diagnosis of OI plus non-accidental trauma (NAT) must
rely on a comprehensive assessment of the clinical find-
ings in the particular child.
These and other case studies have led to a greater
interest in molecular testing for OI in many, if not most,
cases of suspected NAT. This testing provides impor-
tant information to prosecutors, family court attorneys
and defense attorneys. In the criminal court, medical
providers need to be able to exclude OI
to a reasonable
degree of medical certainty
in cases where the diagnosis
is NAT. Therefore, the best practice for prosecutors is
to ensure that child abuse specialists and treating pedi-
atric specialists can rule out OI during the pre-arrest
phase of the criminal investigation. Prosecutors should
encourage medical providers and law enforcement to
gather a complete family and patient health history
during the investigation phase. This information will
serve either to strengthen a child abuse diagnosis by
ruling out a family history of metabolic bone disorder
and confirming that there are no clinical manifestations
of such a disorder, or this information may inform the
prosecutor at an early stage that criminal charges are
not warranted. If OI cannot be ruled out to a reasonable
degree of medical certainty, then charges should not be
brought.
CLINICAL AND RADIOLOGIC
MANIFESTATIONS OF
N
ON-ACCIDENTAL TRAUM
A
The presence of multiple unexplained fractures
is often the initial presenting sign of non-accidental
trauma (NAT). Additional clinical indicators including
the presence of subdural hematomas, skull fractures,
retinal hemorrhages and abdominal injuries may also
be present. A large body of literature has detailed the
“classic” radiologic manifestations of NAT. However,
there can be wide variability in presentation.
Skeletal trauma is the most common manifestation
of physical abuse, constituting up to 87% of all injuries
seen.
7-12
The most common as well as the most specific
injuries for NAT are posterior rib fractures and classic
metaphyseal lesions (CML or “bucket handle” frac-
tures).
12-17
Other patterns of skeletal injury which raise
concern for NAT include fractures inconsistent with
provided history or with developmental stage of the
child, as well as multiple fractures in different stages of
healing. Multiple fractures are present in up to 66% of
cases of abuse.
10,16,17
In evaluation, a subjective assess-
ment for the presence of osteopenia or osteomalacia is
essential to exclude consideration for other etiologies of
multiple fractures.
Rib fractures have been found in up to 50% of abused
infants.
14,17
The mechanism of injury, delineated by
Kleinman, is an antero-posterior compression of the
chest,
12
and due to the tight chondrovertebral attach-
ment, posteriorly placed fractures occur most commonly,
followed by laterally located fractures. These rib fractures
are typically bilateral, multiple and healing at the time of
imaging (
Figure 42.1a,b
). In the absence of a significant
trauma history or underlying osteopenia/osteomalacia,
rib fractures in a child should be viewed with concern.
Rib fractures due to birth trauma
18
and cardiopulmonary
resuscitation have been shown to be distinctly rare.
19
Classic metaphyseal lesions (CMLs) are highly spe-
cific for abuse and occur when the bone is subjected to a
torque force causing a shearing injury across the primary
spongiosa, the weakest and most immature part of the
metaphysis.
20
Depending on the radiographic projection
and the thickness of the sheared disc of bone, the appear-
ance may be that of a “corner” or a “bucket handle”
(
Figure 42.2a,b
). CMLs most commonly involve the lower
extremities and in about half of the patients, the CMLs
are bilateral, multiple and asymptomatic when found.
8,21
CMLs can occur rarely due to birth trauma,
22
and a single
CML has been reported to occur in a case from serial cast-
ing repair of a clubfoot.
23
In these instances, however, the
CML is typically single and immediately apparent clini-
cally leading to imaging. Because CMLs do not typically
heal with the classic subperiosteal elevation seen in other
fractures, they can present challenges with dating of the
