Healthcare and Medicine Reference
In-Depth Information
Back to our slump: eventually, fibroblasts in the area
(and additional mesenchymal stem cells or fibroblasts
that may migrate there) secrete more collagen in and
around the muscle to create a better strap. The long col-
lagen molecules, secreted into the intercellular space by
the fibroblasts, are polarized and orient themselves like
compass needles along the line of piezo-electric charge,
in other words, along the lines of tension (Fig. 1.14). They
bind with each other with numerous hydrogen bonds
via the interfibrillar glue (proteoglycans or ground sub-
stance), forming an inelastic strap-like matrix around
the muscle.
Figure 1.15 illustrates this phenomenon very well. It
shows a dissection of some of the fascial fibers running
over the sternum between the two pectoral muscles. If
we compare the fibers running from upper right to
lower left, we can see that they are denser and stronger
than those running from the upper left to the lower
right. This means that more strain was habitually present
in that one direction, perhaps from being left-handed,
or (entirely speculatively) from being a big city bus
driver who used his left hand predominantly to drive.
This strain caused lines of piezo-electricity, and the
fibroblasts responded by laying down new collagen,
which oriented along the lines of strain to create more
resistance.
Meanwhile, the muscle, overworked and undernour-
ished, may show up with reduced function, trigger-
point pain, and weakness, along with increased
thixotropy in the surrounding ground substance, and
increased metabolite toxicity. Fortunately - and this is
the tune sung by Structural Integration, yoga, and
other myofascial therapies - this process works
pretty well in reverse: strain can be reduced through
manipulation or training, the fascia reabsorbed, and
the muscle restored to full function. Two elements,
however, are necessary to successful resolution of these
situations, whether achieved through movement or
manipulation:
Fig. 1.13 (A) The ECM is designed to allow the relatively free flow
of metabolites from blood to cell and back again in the flow of
interstitial fluid and lymph. (B) Chronic mechanical stress through
an area results in increased laying down of collagen fiber and
decreased hydration of the ECM's ground substance, both of
which result in decreased nourishment to certain cells in the 'back-
eddies' caused by the increased matrix.
meridians). Essentially, these muscles or parts of muscles
are being asked to act like straps (Fig. 1.13A and B).
Stretched, a muscle will attempt to recoil back to its
resting length before giving up and adding more cells
and sarcomeres to bridge the gap. 2 5 Stretch fascia quickly
and it will tear (the most frequent form of connective
tissue injury). If the stretch is applied slowly enough, it
will deform plastically: it will change its length and
retain that change. Slowly stretch a plastic carrier bag to
see this kind of plasticity modeled: the bag will stretch,
and when you let go, the stretched area will remain, it
will not recoil.
In short, muscle is elastic, fascia is plastic. 26,2 7 While
this is a clinically useful generalization for the manual
therapist, it is not strictly true. Certain fascial tissues -
the ear, for instance - have higher proportions of elastin
that render the non-muscular tissue quite deformably
elastic. Beyond that, however, certain arrangements of
pure collagen have elastic properties that allow for the
storage of energy in extension and a recoil shortening
as that energy is 'given back'. The Achilles tendon, for
instance, is quite compliant, and it has been shown that
in human walking and running the triceps surae (soleus
and gastrocnemii) basically contract isometrically while
the tendon cycles through stretch and shortening. 28_3Ca, b
The mechanism of fascial deformation is incompletely
understood, but once it is truly deformed, fascia does
not 'snap back'. Over time and given the opportunity -
i.e. bringing the two fascial surfaces into apposition
again and keeping them there - it will, however, lay
down new fibers that will rebind the area. 3 1 But this is
not the same as elastic recoil in the tissue itself. A full
understanding of this concept is fundamental to the
successful application of sequential fascial manipula-
tion. Practicing therapists in our experience make fre-
quent statements that betray an underlying belief that
the fascia is either elastic or voluntarily contractile, even
though they 'know' it is not. The plasticity of fascia is
its essential nature - its gift to the body and the key to
unraveling its long-term patterns. We will return to
fascial contractility and elasticity at the cellular level in
the section on 'tensegrity' below.
1. a reopening of the tissue in question, to help
restore fluid flow, muscle function, and connection
with the sensory-motor system,
and
2. an easing of the biomechanical pull that caused
the increased stress on that tissue in the first place.
Either of these alone produces temporary or unsatis-
factory results. The second point urges us to look beyond
'chasing the pain' and calls to mind the prominent phys-
iotherapist Diane Lee's admonition: 'It is the victims
who cry out, not the criminals.' Taking care of the victims
and collaring the local thugs is addressed by point 1,
going after the 'big shots' is the job of point 2.
In the slump pictured in Figure 1.12 (reminiscent of
Vladimir Janda's upper crossed syndrome 32 ), the muscles
in the back of the neck and top of the shoulders will
have become tense, fibrotic, and strained, and will
require some work. But the concentric pull in the front,
22
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