Dear Dr. Zapf,
I had two surgeries for
Morton's neuroma. top and bottom 15 years ago and the
pain is back more
severe than ever and I. cannot walk.
Do you do it a third time?
Stephanie
Dear Stephanie:
First things first, do you and did you have a neuroma in
the first place. A neuroma is a swollen nerve that is commonly found in the foot
between the 3rd and 4th metatarsal heads. IT is painful to squeeze the
metatarsal heads (the area of the foot just behind the toes) together and a
doctor can actually feel a click when he or she pops the nerve up and down
between the metatarsal heads with our fingers. The diagnosis is usually made
this way - 95% just by fee. X-rays are taken to rule out other pathology like
bone cysts and spurs. I, and many other doctors, use a diagnostic\, picture
taking ultrasound to visualize and size the neuroma. Neuromas have very
characteristic pictures with ultrasound and we can measure their diameter.
Neuromas less than 5mm usually respond to a cortisone injection or two. Between
5 and 10mm may respond to injections plus a series of alcohol injections, called
sclerosing or, more properly, alcohol neurolysis. Neuromas over 10mm usually
fail to respond to non-surgical solutions and need surgery. If there is any
question about a lesion being a neuroma we can order an MRI to get a better
picture of the lesion. Now, I am going to assume that you already have done all
of this, it was diagnosed correctly, was surgically corrected properly with a
pathology report indicating a neuroma.
To see a picture of a neuroma removed at surgery click
on --> Neuroma
For more information on Neuromas click on -->
Neuromas
(Note: sometimes a pain in the interspace is not a neuroma
and is, instead, damage to the toe-foot joint (the metatarsophalangeal joint)
that is irritated when your doctor feels for thee nerve. Sometimes you can have
both. Your doctor needs to be good with his or her fingers)
Here is a little secret: neuromas can recur. The nerves
can grow back. We know nerves grow back every time there is a successful hand
re-attachment. If the nerves did not repair themselves, there would not be any
movement in the fingers of the reattached hand. Nerves grow a millimeter or so a
month after severing. If an examination shows you likely have a neuroma and
it is visualized on an ultrasound or an MRI, a third excision is a reasonable
approach.
First, however, I would consider a non-surgical approach
to treating the neuromas. The first of the two approaches I can recommend is the
aforementioned alcohol neurolysis. Your doctor will inject about 1/2 CC of 4%
alcohol in anesthetic solution just proximal to the neuroma on a weekly basis
for 8 weeks. One third of the time the neuroma will response wonderfully and
hurt no longer. One third of the time the nerve will improve some and surgery
can be avoided. One third of a time there is no positive response. The good news
is that this method never has any side effects and can be done again, in a few
years, if necessary. I personally love procedures that have no negative side
effects.
For more information on alcohol neurolysis click on
--> Neurolysis
A final method is very new and only a few of us can do it
called Radiofrequency Ablation or RFA. With RFA an electrode is placed against
the nerve and turned on for 30 seconds to "ablate" or kill the nerve. This is a
common approach used by orthopedists, cardiologists, neurosurgeons and cancer
surgeons, but it is very new in podiatry. I doubt that you will find an RFA
trained podiatrist in your area as the technique is so new but it should become
more common in a year or two. Maybe you can use the alcohol method for now.
Good luck and let me know what method is chosen and how
you do.
Michael Zapf, DPM
