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In Depth Tutorials and Information
CHAPTER
47
Pediatric Limb Reconstruction in
Ost
eogenesis Imperfe
cta
Steven L. Frick
1
, Paul D. Sponseller
2
and Arabella Leet
3
1
Nemours Children's Hospital and University of Central Florida College of Medicine, Orlando, FL,
USA,
2
Johns Hopkins School of Medicine, Baltimore, MD, USA,
3
Shriners Hospitals for Children®,
Honolulu
INTRODUCTION
telescopic intramedullary fixation and aggressive medi-
cal management of patients with OI.
1-3
Thus, parents of
children undergoing surgical limb reconstruction should
know that multiple corrective surgical procedures may
be required.
Children with osteogenesis imperfecta (OI) often
have extremity deformities, typically bowing abnormali-
ties that develop as the growing long bones bend and/
or break in response to the stresses place upon them by
developing muscles and gravity. Prevention of progres-
sive deformity may be possible with bracing, although
controlled evidence for this is not available. Clinical
studies of the effectiveness of any intervention in OI
is scientifically challenging, as the small numbers of
affected individuals, and the variations in severity of
involvement of the long bones, make the establishment
of appropriate control groups challenging. Correction
of lower extremity deformity in OI can improve func-
tion and decrease the risk of an acute fracture. The cor-
rection of upper extremity deformities is performed less
commonly, but can also result in improved function and
diminished fracture risk. Deformity can vary in severity
depending on patient phenotype; however, for the indi-
vidual patient there can be a certain anatomic location
that has a severe deformity, while the spine or a differ-
ent limb is relatively spared of deformity. Non-operative
management of deformity includes medication and
bracing. Surgical indications for deformity correction
include severe bowing that prevents proper positioning
of the limbs for weight bearing or function, or smaller
amounts of deformity at a site with a history of multiple
fractures. Deformity can develop throughout the life of
the patient, especially during periods of rapid growth.
Recurrence of deformity following operative straighten-
ing of the bone over time is common, even in the era of
ETIOLOGY OF DEFORMITY
Deformity in OI can occur as a result of small micro-
fractures or in the setting of an acute fracture followed
by healing in a malaligned position. Children with the
more severe phenotypes of OI can be born with limb
bowing; others with a mild type I phenotype often have
no signs of limb deformity at birth. Bowing occurs as a
result of weakness in the bone combined with the forces
placed across the bone provided by the muscle and body
weight. Most children have the typical patterns of bow-
ing including anterolateral bowing of the femur, anterior
bowing of the tibia with varus at the ankles and antero-
lateral humeral bowing with cubitus varus at the elbow.
Proximal femoral deformity with coxa vara is also com-
mon, and is difficult to treat. With acute fracture, the long
bones can angulate, shorten and twist. Much attention
is focused on the coronal and sagittal plane deformi-
ties as they are easily seen in standard anteroposterior
and lateral radiographs, but transverse plane (torsional)
deformities are also frequently present, and can be func-
tionally limiting, especially in the tibia. Disuse osteo-
porosis that occurs as a result of immobilization for
fracture or osteotomy care can, in turn, cause increased
risk of fracture once the immobilization is discontinued
