If you are like me, you
may have wondered why it is that the shoulder is the most common first noticed
complaint in Neuralgic Amyotrophy attacks. Maybe it never crossed your mind after
all. I figure, if there is a causal
agent in the bloodstream, and it finds the shoulder plexus site to attack, it
is just as likely to find other nerves at other plexus sites. It may be clever, but is it really smart
enough to be that specific? If you listen
to most doctors, they would suggest “yes”, it is that specific. If you have any other issues in other areas
with weakness, it is either all in your head, or you have something else they
can charge thousands of dollars to test for, and come up with nothing. “Oh well, nothing wrong with you- got to
scoot”.
If you
read the document (linked above), there are two things talked about which
suggest a reason for the shoulder being the most common joint impacted with
NA. It begins with overall muscle loss, and
ends with the efficiency of muscles to do work with impeded nerve
connections. The author first speaks of muscle
loss, stating that
“In
daily life, people generally do not notice that they are losing muscle strength
until
they have lost around 30% of their maximum strength. The strength that lies
between
70% and the maximum of 100% is, as it were, ‘extra’ in case heavy exertion
must
unexpectedly be made.”
So, you
could have an attack of NA that leaves you with a gradual loss of muscle strength
to say 75% of normal, and not even notice it.
I think this actually happened to me, looking back. I had had an attack
that impacted my right hand and left my arm weak. But otherwise, I had no clue
what was going on, except, on a long car trip, I noticed a bit of shaking at
times getting into or out of the car.
Time
passed, and one night I woke up on my right side and noticed that my shoulder
popped, and collapsed a bit. There was no pain, just the sensation of settling
that did not feel normal at all. Why would
this be important? Look to the document again.
“For
most of the muscles, one can say that they function well in daily life
once
they have regained 70% of their former strength. However, some muscles
must
truly be nearly 100% recovered before they can function normally again.
The
muscle that, when it fails, causes a protruding shoulder blade, (the serratus
anterior)
is the most important example of this. Because this muscle needs its
maximum
strength and endurance in order to work well, it sometimes seems as
if
recovery of the nerve to this muscle takes much longer than the recovery of the
other
nerves.”
It
would seem possible that the muscles surrounding the shoulder are a bit more sensitive
to nerve loss than other sites in the body. So that may explain why the shoulder
is the first noticed spot that NA impacted, when truly, it is everywhere to
some extent. They go on to say:
“With
neuralgic amyotrophy, the strength in the affected muscles is often decreased
to
(much) less than 50% of the maximum. It is often not even possible
anymore
to carry – or lift – the weight of the arm itself, let alone an extra weight
(for
example, a purse or bag). It also becomes difficult to maintain movement or
postures.
It is sometimes possible to make a specific movement once (such as
extending
the arm or putting something in the cabinet above your head) but it is
not
possible to do that a number of times or to keep doing it for a specific period
of
time. Both the loss of strength and the difficulty with maintaining movement
are
serious impediments for NA patients in their daily work, sports or activities
at
home.”
Add to
that that any regained strength may be to a lesser amount than what existed
prior to the attack. For HNA sufferers, this is augmented by having many more attacks
over a lifetime.
Speaking
of returning strength. . . Do not do as I did and force it to get better. Heavy exercise prior to complete healing can
lead to further nerve damage and make that nerve even more susceptible to further
attacks in the future.
“If,
within a nerve bundle, no more than two thirds of the axons are damaged, then
the
remaining axons will take over the work of the damaged cables within three
to four
months. This mechanism is called: ‘collateral reinnervation’. This repair
mechanism
works well because the muscle can then again be completely controlled.
However,
this is at the expense of some load endurance. That means that the
muscle
can certainly provide maximum strength once but cannot maintain it well
or keep
it up for long. In daily life, patients often notice that, after a time, they
can,
in
principle, carry out all of the movements with the arm, but that the arm
becomes
heavy
and tired after being used for awhile and they must stop and rest before
they
can continue with what they were doing.”
“If the
nerve has been affected a number of times, the chance of recovery decreases.
Also,
nerves are not able to tolerate everything: If they become even more
damaged,
they will be ‘broken’ for good. In practice, this means that the function
of, for
example, the arm after an initial period of painful loss of function will still
recover
for the most part, but that, after a second or third time, will not recover as
completely
and, ultimately, will not be able to recover at all. The loss of strength,
but
also the disorders in sensation and blood supply to the skin, then become
permanent.”
