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CHAPTER
46
Treatment of Fractures and Non-
Unions in Children with Osteogenesis
Imperfecta
Lewis E. Zionts and Richard E. Bowen
Geffen School of Medicine at UCLA, Los Angeles, CA, USA
INTRODUCTION
quantity of type I collagen. This quantitative defect is the
result of various mutations in the COL1A1 or COL1A2
genes that code for type I collagen. The mode of inheri-
tance is autosomal dominant.
Type II OI is the most severe form of the disorder and
is characterized by extremely fragile bone, often resulting
Osteogenesis imperfecta (OI), also known as brittle
bone disease, is a clinically heterogeneous group of heri-
table disorders generally caused by defective collagen
synthesis. The common clinical features of the disorder
include low bone mass and reduced mechanical strength,
often leading to frequent fractures, development of pro-
gressive long bone deformity and growth deficiency.
The goals in managing patients with OI are to minimize
fractures, limit deformity and enhance function and
independence.
Over the past decade, a multidisciplinary team
approach has been used to attempt to reduce the number
of fractures and lessen the development of deformity in
these children. This approach includes medical manage-
ment, most notably the use of bisphosphonates, physical
therapy and intramedullary fixation of the long bones.
C
LASSIFICATION SYSTEMS
Sillence et al.
1-3
classified OI into four distinct groups
based on phenotypic features, radiologic appearance of
the bones and the mode of inheritance. Their system is
currently the most widely used.
Type I OI is the most common and mildest form of the
disorder. These patients have distinctly blue sclera, no
dentinogenesis imperfect (DI), few fractures and mini-
mal deformity of the limbs and spine (
Figure 46.1
). These
patients often sustain their first fracture when they begin
to walk. Type I OI is classically due to a reduction in the
FIGURE 46.1
Radiographs of a 9-year-old boy with type I OI.
Osteopenia is present, but there is minimal deformity of the long
bones.
(From Zionts LE, Ebramzadeh E. Internal fixation in patients with
osteogenesis imperfecta. In An Y, ed.: Internal Fixation in Osteoporotic
Bone. New York: Thieme, 162-177, 2002, with permission.)
