Of the spectrum of metallic
instrumentation techniques developed in spine surgery, pedicle screw fixation has
gained the most popularity. As the technique and technologies for placement of
percutaneous pedicle screws have progressed, so have the indications for
their placement. Most surgeons will use
percutaneous pedicle screw fixation as an adjunct to an anterior or posterior
minimally invasive procedure. However, one indication used in our practice is for
patients who suffer from spinal fractures that, unfortunately, either cannot
tolerate external bracing or do not want to lose the extra motion segments in
their spine by undergoing a permanent spinal fusion procedure. The placement of
percutaneous pedicle screws effectively acts like an “internal bracing” system
which, after the fracture heals, can be removed without any long-term
consequences.
Illustrative Case
A 21 year old woman presents to
the emergency room following a motor vehicle accident. She has severe back pain
but is neurologically intact on examination. A work-up reveals an L1 stable
burst fracture (Figure 1). The
patient is placed in a rigid brace but cannot tolerate wearing the brace
because it exacerbates her fibromyalgia thus resulting in intolerable amounts
of back pain. Given her young age, the
option to “internally” brace the patient with internal fixation is chosen with
the plan for scheduled hardware removal once the fracture has healed. The idea of fusing a minimum of two to three
levels of her spine is a less ideal choice. Surgery is completed the following
day with minimal blood loss and she is discharged home one day later without a
brace (Figure 2). Approximately 12 months after placement of
the internal hardware, it is removed as scheduled (Figure 3). The patient
remains with motion above and below the fracture level with no consequences to
the procedure except for the small stab incisions on her skin (Figure 4).
Figure 1. CT lumbar spine
with sagittal (first) and axial (second) reconstruction shows an L1 stable burst
fracture.
Figure 2. Upright standing AP/lateral
x-rays show hardware fixation of the L1 fracture with percutaneous pedicle
screws placed in T12, L1 and L2.
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Figure 3. Upright standing lateral x-ray demonstrates the L1 fracture
with improved alignment following the removal of the hardware.
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| Figure 4. Stab incisions from the placement of the screws compared to a dime (<18 mm in diameter). |
