Isthmic spondylolisthesis: surgeon
viewpoint
This patient presents a long-standing isthmic
spondylolithesis. His pain is well described
as occurring in the L5 nerve root-pain and weakness
in his big toe. An important part of his history
is the extent to which this limits his activities.
It is unreasonable for a healthy 43-year-old
to be only able to walk 100 feet, when there
are means to treat the underlying problem.
As in most instances, one can either entertain
non-operative or surgical options. The nonsurgical
treatments however are less likely to have long
term benefit. Although there are many NSAIDs
on the market, it is unlikely that changing to "newest
and best" or the "one in the ads" will
he helpful. He should be encouraged to continue
his aerobic exercise. There is no evidence that
either physical therapy, chiropractic care or
traction would work in this diagnosis. He may
benefit from a selective block, with local anesthetic
and cortisone, to the right L5 nerve root. I
suspect that this will provide only short-term
relief. It will help to confirm the diagnosis.
Surgical treatment program
Surgical treatment needs to address the nerve root compression. Traditionally
this has been done by a laminectomy. He would also require a fusion (arthrodesis)
at L5 to the sacrum. This could be done with bone graft from the pelvis and
pedicle screws. Given the disc collapse, a single level fusion in a non-smoker,
it would not be necessary to do an interbody fusion with the posterior fusion.
The disadvantage to this approach is the trauma to the back muscles. It is
also associated with a longer recovery time.
My preferred surgical option would be indirect
decompression of the nerve root by an anterior
interbody fusion with cages. There is much less
trauma to the patient with this type of surgery.
By lifting the disc back up to its normal height
the pressure is removed from the nerve. Likewise
the fusion rate is very good with a single level
fusion. It also allows me to preserve the function
of the "back muscles." This should
shorten his rehabilitation time after surgery.
I would not operate at the L4-L5 level. He does
not have any complaints of back pain. I do not
think discograms would be helpful. Although,
irrespective of the surgical fusion technique,
he is at some increased risk of the L4-L5 level
degenerating in the future. There is no way to
predict whether this will give him symptoms.
Long-term studies of patients fused as children
for spondylolithesis do not show dramatically
higher rates of spinal pain.
By:
John E. Sherman, MD
October 10, 2000 |
