Craniofacial Anomalies, Part 2 - Plastic Surgery Internal

Fig 10. Cranial sutures in the human fetus. Premature closure
produces growth restriction perpendicular to the line of the
suture and compensatory overgrowth parallel to it.
Scaphocephaly (dolichocephaly) is due to premature
fusion of the sagittal suture. Features of sagittal
synostosis include a palpable ridge overlying the sagittal
suture, decreased biparietal diameter, and elongation
of the skull in the anteroposterior dimension.
Significant frontal and occipital bossing are commonly
noted. The appearance resembles a boat or “scaphe.”
Plagiocephaly stems from the Greek word meaning
“crooked head”, and is an asymmetrical deformity.
It may be anterior or posterior. Two etiological
variants must be distinguished – deformational
and synostotic.
Posterior plagiocephaly is usually positional and a
result of the child lying predominately on his/her
back. It produces a classic parallelogram skull
deformity. 139 The incidence has increased with the
recommendation by the American Academy of
Pediatrics to lay infants on their backs to reduce the
risk of sudden infant death syndrome (SIDS). 140,141
Treatment of positional plagiocephaly depends on
SRPS Volume 10, Number 17, Part 2
the severity of the deformity and often requires helmet
therapy for correction in severe cases. However,
large studies have shown little difference in
outcome between helmet therapy and consistent
repositioning of the infant off the flat spot in mild to
moderately severe cases. 141,142
Posterior synostotic plagiocephaly can also result
from unilambdoid synostosis. Unilambdoid synostosis
is a very rare entity.
Brachycephaly is the result of bicoronal synostosis
and is characterized by anteroposterior shortening
of the skull. The lower part of the forehead and
supraorbital bar are retropositioned. This is the
characteristic head shape deformity that accompanies
Apert and Crouzon syndrome, and in these
cases it is believed to be due to abnormalities that
extend into the cranial base, causing the associated
facial deformities of exorbitism and maxillary retrusion.
Posterior brachycephaly is unusual but can
be the external manifestation of bilateral lambdoid
suture synostosis.
Turricephaly (towering head deformity) is characterized
by excessive skull height and a vertical forehead.
This deformity is typically an untreated
brachycephaly where compensatory expansion leads
to an increasing vertical height to the cranium. Children
with Apert syndrome have a particular tendency
toward turricephaly.
Oxycephaly is a pointed head. The forehead is
retroverted and tilted back in continuity with the
nasal dorsum. Oxycephaly is usually due to fusion of
multiple sutures.
When multiple sutures are involved, head shapes
are more variable and the distinctions blur. In these
cases the specific sutures involved should be named
when describing the deformity. The kleeblattschadel
or cloverleaf skull deformity results from pansutural
synostosis, and usually requires early, aggressive treatment
to prevent cerebral compromise.
Craniofacial Growth
The cranium is made up of the neurocranium,
which includes the chondrocranium of the skull base
and the membranous bone of the calvarium, and
the viscerocranium, which forms the membranous
bones of the face. The various areas of the
craniomaxillofacial skeleton grow by very different
methods. The cranial sutures are skeletal joints of
the syndesmosis type as well as being sites of osteo-
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