I was lucky. I found an orthopedic surgeon that specializes in FEET. He went in through the top of the foot and snipped the median nerve right down the middle to the back of the fourth toe right foot. Here's a better explanation of what a Morton's Neuroma is and a short video animation I found.
Lupus is different in every patient. Mine likes to attack my peripheral and cranial nerves, skin and blood. This is just one example of what lupus can do.
From myfootshop.com:
Morton's
Neuroma is a painful condition of the forefoot that is caused by the
entrapment of the common intermetatarsal nerve as it passes through the
forefoot to the toes. This condition was first described by Dr. Morton, a
Viennese physician, in 1876. The most common location for Morton's
neuroma is between the third and fourth toes. The second most common
location is between the second and third toes.
To
help understand this condition a bit better, let's break down the word
neuroma into its' root form. Neuro relates to the nervous system and in
this case, we are describing a portion of the peripheral nervous system.
The suffix 'oma' is the Latin term that defines a tumor or swelling
that is of primary origin. Put the terms together and what is described
is a tumor or swelling of a peripheral nerve. Interestingly, a Morton's
neuroma is not truly a tumor, but more accurately, a nerve entrapment.
Although the term neuroma is somewhat inaccurate in describing this
condition, the term neuroma is still used today to describe this unique
nerve entrapment. Other terms may be used to describe Morton's
neuroma. These terms include intermetatarsal neuroma, Morton's
metatarsalgia, Morton's neuralgia, plantar neuroma, intermetatarsal
perineural fibroma or intermetatarsal nerve entrapment.
What
causes Morton's Neuroma? Why does the intermetatarsal nerve become
entrapped? Clinicians and surgeons recognize a number of factors that
may aggravate Morton's neuroma, but the primary cause of Morton's
neuroma remains elusive. Shoes that are tight in the forefoot will
contribute to the symptoms of Morton's Neuroma by binding the forefoot
and compressing the common intermetatarsal nerve. High heels will also
act to increase the ground reactive forces. Ground reactive force is the
amount of force generated as the foot pushes against a fixed surface
like the floor. With high heels, the amount and focus of ground reactive
force increases since weight bearing is focused in a smaller area (just
the forefoot). A higher heel also puts the common intermetatarsal nerve
under tension, making it more prone to injury. Activities such as
squatting will increase the ground reactive force applied to the plantar
foot and aggravate the symptoms of Morton's neuroma. And finally,
clinician also agree that hypermobility of the forefoot can contribute
to the formation of Morton's neuroma.
Treatment of Morton's neuroma
It's
interesting to note that until the early 1990's, we treated Morton's
neuroma in same way as described by Dr. Morton some 100 years ago. But
over the past ten years, our understanding and treatment of neuromas has
changed dramatically. Our understanding of Morton's neuroma as an
entrapment and not a tumor can be attributed to the work of Steve
Barrett, DPM. Dr. Barrett was the first to take a critical look at
Morton's neuroma and describe it as an entrapment rather than a tumor.
What
Dr. Barrett recognized was that the common intermetatarsal nerve is
sometimes prone to becoming entrapped as it passes beneath the
intermetatarsal ligament. This was a new concept for us in light of the
fact that we had considered Morton's neuroma a tumor. In fact, Dr.
Barrett's findings enabled us to recognize Morton's Neuroma to be
similar to other nerve entrapments such as carpal tunnel syndrome or
tarsal tunnel syndrome. Subsequently, the treatment of Morton's Neuroma
has been slowly changing over the last ten years as the result of a new
endoscopic surgical procedure first described by Dr. Barrett.
Diagnostic
testing to evaluate Morton's neuroma includes plain x-rays, diagnostic
ultrasound and MRI. Plain x-rays are not actually used to visualize the
nerve, but are use rather to screen for bone and joint pathology
adjacent to the nerve. Metatarsal fractures, Freiberg's infraction and
osteoarthritis are common conditions that can influence the behavior of
Morton's neuroma and need to be evaluated with x-ray.
Several
authors have suggested that the efficacy of MRI and ultrasound as
diagnostic tools are comparable when evaluating patients for Morton's
neuroma. Diagnostic ultrasound is significantly less expensive and much
more readily available compared to MRI. Kankanala et. al described a
91.48% pre-op predictive value for diagnostic ultrasound when screening
for Morton's neuroma.
Conservative care of Morton's
neuroma can be quite successful. 70% or more of new Morton's neuroma
patients respond to simple changes in shoes such as a wider toe box.
Shoe padding can also help treat Morton's neuroma. Metatarsal pads
are an important tool for patients with Morton's neuroma symptoms. A
metatarsal pad is a small lift that is positioned in the shoe just
proximal (behind) the weight bearing surface of the metatarsal bones. A
metatarsal pad lifts and separates the metatarsal bones thereby
decreasing the pressure on the intermetatarsal nerve. Some prefabricated arch supports
come with a metatarsal pad already seated in the correct position.
Using inserts with a metatarsal pad is sometimes the easier way to use a
met pad because they can be easily moved from shoe to shoe. Also, by
using an insert with a fixed metatarsal pad, the position of the met pad is always in the correct location.
Other
non-surgical methods of treating Morton's neuroma include injectable
cortisone and chemical sclerosis of the intermetatarsal nerve. Cortisone
has been used successfully for years in treating Morton's neuroma.
Although the use of cortisone does not actually treat or change the
entrapment of the intermetatarsal nerve, cortisone can decrease
inflammation and swelling of the nerve, resulting in a decrease in pain.
Care should be exercised when using cortisone injections noting that
excessive cortisone injections can thin the plantar fat pad of the foot.
Sclerosis
of the nerve (also called chemical neuro-ablation or chemical
neurolysis) can be performed in the office using a number of different
solutions, most commonly dilute (4%) alcohol. Multiple sclerosing
injections are used to destroy the contents of the peripheral nerve. A
series of injections are employed, each injection separated by a period
of 7-10 days. The total number of injections may vary from 3 to 7. The
success rates of injectable sclerosing solutions have been reported to
be as high as 60-90%. Chemical neurolysis is also a great tool for
failed neuroma surgeries where a stump neuroma has formed.
The
intent of chemical neurolysis is to destroy the internal contents while
preserving the external sheath of the nerve. This would be a bit like
removing the copper wire in an electrical wire while preserving the
plastic outer insulation or cover of the wire. The reason that this is
important is due to the fact that peripheral nerve will regenerate over
time. With the nerve sheath intact, regeneration of the nerve is
possible in a controlled manner utilizing the existing sheath. By
contrast, removal of the nerve by surgery results in the nerve
regenerating and the formation of a mass of scar tissue called a stump
neuroma. Knowing that peripheral nerve may regenerate also means that
sclerosing injections may need to be repeated at some point in the
future. The percentage of repeat sclerosing injections varies but is
overall quite low.
Another new technique used to
treat Morton's neuroma is called cryogenic neuroablation. Cryo surgery
is surgery that uses extremely cold instrumentation to selectively
destroy tissue. Cryosurgery has been used commonly to destroy
superficial skin lesions such as warts and moles. The technique uses
what is referred to as the Joule-Thompson effect. The Joule-Thompson
effect occurs when a gas is passed through an area where it may expand.
As the gas expands, it cools to approximately -70 degrees centigrade .
In the case of cryogenic neuroablation, the expansion of the gas is
controlled in a 5.5 mm probe that freezes and subsequently destroys the
nerve tissue.
In the cryogenic ablation study carried
out by Drs. Caporusso, Fallet and Savoy-Moore, thirty one neuromas were
treated in 20 patients. All procedures were performed in an office
setting. The procedure used a small amount of local anesthetic to numb
the skin to allow the passage of a 12-gauge cannula through the skin. A
nerve stimulator was passed through the cannula to locate the nerve.
Once the position of the nerve was established, two three minute freeze
sessions were utilized to destroy the nerve tissue. A sterile dressing
was applied to the site and the patient was dismissed without the need
for pain medication. The study cites a 65% success rate.
Dr.
Morton's original treatment plan as described in 1876 included changes
in shoes, multiple injections of cortisone and if necessary, complete
excision of the common intermetatarsal nerve. We've mentioned before
that Morton's neuroma is a nerve entrapment much like carpal tunnel. Now
let's see if we can apply Dr. Morton's treatment plan to any other
nerve entrapment such as carpal tunnel syndrome. Perhaps we'd splint the
wrist, try some injectable cortisone, but completely excise the nerve?
No way. But that's what's been done for the past 100 years for Morton's
Neuroma. Post-op complications were common and included thinning of the
plantar fat pad and loss of sensation in the 3rd and 4th toes.
The
introduction of Dr. Barrett's EDIN procedure has revolutionized the
treatment of Morton's Neuroma and really represents the first unique
contribution to treating this condition in over 100 years. The EDIN
procedure stands for endoscopic decompression of the common
intermetatarsal nerve. Interestingly enough, Steve describes first
thinking about this procedure as he watched another surgeon perform an
endoscopic carpal tunnel surgery. Steve recognized the problem to be the
ligament and not the nerve. The EDIN procedure selectively releases the
ligament and leaves the nerve intact.
The EDIN
procedure provides us with a new alternative. In the past we knew that
the traditional surgery used to treat Morton's Neuroma, called a
neurectomy, was destructive and carried with it a number of post-op
complications. Therefore, we would tend to use excessive amounts of
cortisone to avoid surgery. The EDIN procedure provides a new
alternative using non-invasive endoscopic techniques that usually return
patients to activities much sooner than the traditional surgery. And,
what I find most helpful is the fact that it enables us to use less
cortisone, thereby avoiding fat pad atrophy. The question remains; was
the common complication of fat pad atrophy due to the neurectomy itself
or did it result from the overuse of cortisone? The EDIN procedure shows
none of the traditional post-op complications that were so commonly
seen in the neurectomy, therefore we can assume that fat pad atrophy was
in part due to overuse of cortisone.
The EDIN
procedure has been used for at least ten years and has shown promising
results. It can be technically challenging for some who are not familiar
with endoscopic techniques. As with other surgical procedures there are
pros, cons and possible complication that need to be discussed
thoroughly with your physician prior to surgery. The following pictures
show the technique used to perform an EDIN procedure. Image 1 shows
pre-operative markings identifying the 3rd and 4th metatarsal heads.
Image 2 shows placement of the cannula through an interdigital incision.
The cannula is much like a small 4mm drinking straw with a slot cut in
one side. The slot or open side of the cannula is placed adjacent to the
intermetatarsal ligament. The cannula passes from between the toes to a
second incision on the plantar aspect of the foot just proximal to the
weight bearing surface. The endoscope and knife are used within the
slotted cannula to identify and transect the intermetatarsal ligament.
Image 3 show the use of a blunt probe without the cannula to verify a
complete release of the intermetatarsal ligament. In the bottom of image
3, a metatarsal spreader can be seen. The spreader is used to separate
the 3rd and 4th metatarsals subsequently putting pressure on the
intermetatarsal ligament. The procedure takes about 20 minutes and is
completed in a hospital or surgery center. Local anesthesia with
sedation is used. Patients return to regular shoes in two days with just
a band-aid on the incisions.
Traditional
neurectomy, or removal of the nerve for the treatment of Morton's
neuroma, is used less often due to the success of sclerosing injections
and the EDIN procedure. Neurectomy can be performed from a dorsal or
plantar approach. The advantage of a dorsal approach is that patients
are able to walk immediately following the surgery. The disadvantage of
the dorsal approach is that it requires more dissections and possible
tissue trauma. The plantar approach results in less tissue trauma but
requires that patients are non-weight bearing on the surgery foot for 3
weeks post-op. Traditional neurectomy for the treatment of Morton's
neuroma is performed on an out-patient basis at a surgery center or
hospital using a local or general anesthetic. The procedure is
completed in less than 30 minutes.
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