Extract
Vertebroplasty, first described by Galibert et
al.1 for the
treatment of vertebral angiomas, is now often used to treat painful
osteoporotic compression fractures of vertebral bodies and the pain associated
with malignant tumor
osteolysis2,3.
Vertebral augmentation with percutaneous injection of polymethylmethacrylate
cement after the use of an inflatable bone tamp is a variant of vertebroplasty
that is commonly called kyphoplasty, a term that we will use
hereafter. Inflation of the balloon tamp elevates the vertebral body end
plates to reduce
kyphosis4-6.
Although infrequent, the complications of these procedures include leakage of
cement into perispinal areas or the epidural space, embolization of cement,
and spinal infection. Cement leakage is responsible for neurologic
complications, including transient radiculopathies and spinal cord
compression2,7,8.
Thermal necrosis is a well-established consequence of cement-curing in
conjunction with
arthroplasty9-11,
but the role of the exothermic polymerization of polymethylmethacrylate in
vertebroplasty is unknown. Temperatures measured in an ex vivo study were
sufficiently high for thermal necrosis to be considered a
possibility12,13.
The authors of a histopathologic
study14 attributed
a zone of necrosis around polymethylmethacrylate cement that had been injected
into a metastatic vertebral tumor to thermal necrosis, but there may be other
causes.