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CHAPTER
49
Joint Replacement in Patients with
Ost eogenesis Imperfe cta
Pierre H. M. Pechon and Simon C. Mears
The Johns Hopkins University/Johns Hopkins Bayview Medical Center, Baltimore, MD, USA
INTRODUCTION
previous intra-articular fracture or altered joint bio-
mechanics. Patients with OI live longer than many cli-
nicians realize and, depending on the subtype of their
disease process, their life expectancy can approach that
of the normal population. 8 Age-related joint degenera-
tion is therefore a distinct possibility as a cause of OA.
Intra-articular fractures that may have been con-
servatively or surgically treated in the past are known
causes of post-traumatic arthritis. A review of the lit-
erature found three case reports (four patients) that
described low-energy acetabular fractures; 9-11 the low-
energy mechanism implies poor bone quality. The first
fracture was sustained falling from a chair; the second
while playing football; the third while walking and the
fourth while transferring from bed to chair at home.
Darmanis and Bircher 9 reported two cases of surgical
fixation of acetabular fractures to preserve the joint. If
those patients subsequently develop post-traumatic
arthritis, their primary arthroplasty will be complicated
by previous scar tissue, metalwork and possibly altered
muscle function.
The role of abnormal ligament structure and
strength in the development of joint arthritis is unclear.
However, it is likely that a structurally abnormal
labrum of the hip or knee meniscus, combined with lax
structural ligaments, could lead to premature arthri-
tis in the hip or knee. These ligamentous abnormalities
make knee replacement more technically challenging.
Ligament balancing, which is critical to a good result,
is difficult in such situations and more constrained
implants may be necessary. 12
Deformity caused by previous fractures may also
lead to abnormal loading of the cartilage across the hip
or knee. This loading then may prematurely wear out
The goal of knee and hip replacement is to reduce
pain and improve function in a joint with arthritis. To
obtain this goal, the surgeon seeks to place a stable
prosthesis with minimum perioperative complications.
Patients with osteogenesis imperfecta (OI) may develop
wear and tear or osteoarthritis (OA) of the hip or knee,
a painful condition treated at first with activity restric-
tion and pain medications. Joint replacement is the
last treatment choice; its goal is to restore function and
remove pain.
There are three processes that affect the joints of the
lower limbs, all of which lead to arthritis in patients
with OI: fractures causing damage to the joint surfaces,
capsule and ligament laxity causing alterations in joint
biomechanics or cartilage loading 1 and long bone defor-
mity from a previous fracture or congenital dysplasia.
Fractures are the major orthopedic complaint, although
joint hypermobility is common in patients with type I
and II OI. 2 Bone deformity secondary to previous frac-
tures in patients with OI can make hip or knee replace-
ment substantially more difficult, and there also may be
indwelling hardware that has to be removed. The bones
of patients with OI are also more susceptible to fracture
during a procedure, which can also increase the diffi-
culty in obtaining a good result. 3-7
PATHOPHYSIOLOGY OF
OSTEOARTHRITIS IN OI
Osteoarthritis may arise from age- and wear-related
degenerative change, post-traumatic arthritis from
 
 
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