 |
Fig.1: Modified from
Atlas of Human Anatomy
by Bernhard N. Tillmann |
The classical
descriptions of the sinew channels in the
Lingshu are somewhat
vague when it come to specifics. There
are a few authors who discuss specific muscle anatomy as it relates to these channels. Notably, David Legge, Giovanni Maciocia, and
Donald Kendall all offer their insight into the sinew channels and
discuss which muscles belong to which channel.
All of these authors
list the peroneus (fibularis) longus and the peroneus brevis as part of the Gallbladder sinew
channel. However, I disagree with this assessment and think they are more
properly classed as a branch of the Urinary Bladder sinew channel. In this post I will give the obvious reasons why others include them as part
of the Gallbladder sinew channel, and then I will explain why I have
come to a different conclusion.
The peroneals are found in the lateral portion of the leg and they overlie the
fibula. Topographically, it would make sense to label these muscles as part of the Gallbladder sinew channel. All of the above
authors list the peroneal muscles as part of this channel; also, anatomist Thomas Myers lists these muscles as part of
the lateral line in his influential book,
Anatomy Trains: Myofascial
Meridians for Manual and Movement Therapists. While his book is not
about the sinew channels of Chinese medicine ("meridians" refers to what he calls "lines" in his book, not to specifically Chinese acupuncture
meridians), his Myofascial Meridians parallel the sinew channels in
many ways and many acupuncturists look to them for reference. His
lateral line would be roughly analogous to the Gallbladder sinew
channel.
So, why do I
disagree with all of these authors? To begin with, I will state that
in my lectures in New York during the training for Sports Medicine
Acupuncture in the 2013-2014 certification cycle, I included them with
the Gallbladder sinew channel. This is despite the fact that the
Gallbladder sinew channel is classically discussed as traveling
anterior to the lateral malleolus while the peroneal muscles travel
posterior to this structure. The peroneus longus does attach to the
iliotibial band as discussed by Myers. Both the tensor fascia lata
(TFL) and the gluteus maximus attach directly into the ITB, and the
gluteus medius and minimus also link with it. These are all muscles
that are associated with the Gallbladder sinew channel.
However, the
peroneus longus also has a strong fascial connection to the biceps
femoris (the lateral hamstring muscle seen in Fig.1). Actually, I feel this is a
stronger connection than that of the peroneus longus – ITB
connection. While there is mechanical force
transmission through the peroneus longus to the ITB, I think it is
not as direct a line of force transmission as that of the peroneus
longus to the biceps femoris.
 |
Fig. 2: Image modified from
Deadman's A Manual of Acupuncture. |
When preparing a
cadaver specimen for an anatomy class for the Sports Medicine
Acupuncture Certification program in San Diego during the 2014-2015
cycle, Matt Callison and I did an experiment to see which line of
pull was more prominent; that of the peroneus longus/biceps
femoris or that of the peroneus longus/ITB. We inserted needles
into the MP of the peroneus longus, biceps femoris, and into the ITB
at approximately GB-31. Then we twisted the needles to get a firm
grasp on the tissue and pulled on the needle. Pulling on the needle
inserted into the biceps femoris MP transmitted force and caused the
needle to move at the peroneus longus MP. Pulling the needle inserted
into the ITB at GB-31 did not create a discernible movement at the
peroneus longus MP. What this illustrated was that there was more of
a transmission of force from the biceps femoris to the peroneus longus than from the ITB to the peroneus longus. It is worth mentioning that there was also a needle inserted at GB-34. When pulling on the needle in the biceps femoris, the needle inserted at the peroneus longus MP moved, but GB-34 did not, despite the fact that these two needles were in very close proximity.
Functionally, this
force transmission is important for sacroiliac joint balance, as it
links heel strike with sacroiliac balance. During dorsiflexion just
before heel strike, the peroneus longus pulls down on the fibular head which adds tension to
the biceps femoris and into the sacrotuberous ligament (which is a
structure that the biceps femoris is continuous with). This tension
through the sacrotuberous ligament then stabilizes the sacroiliac
joint in preparation for heel strike.
The biceps femoris
and the sacrotuberous ligament are part of the Urinary Bladder sinew
channel (Fig. 2). So, functionally and structurally the peroneus longus could
be considered as a branch of the Urinary Bladder sinew channel. And,
this matches nicely with the classical description of this channel.
The Urinary Bladder sinew channel does indeed have a lateral branch
which travels posterior to the lateral malleolus and fits the anatomy
of the peroneus longus.
How does this apply
clinically? First off, when treating the sinew channels many
practitioners treat off-channel ashi points such as trigger points
(TrPs) and motor points (MPs). Often this would include treating local
TrPs for pain. Knowing which sinew channel a muscle belongs to
informs which channel relationships exist and helps with distal (or away) point
selection.
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Fig 3: By ms4denmark [CC BY-SA 2.0
(http://creativecommons.org/licenses/
by-sa/2.0)], via Wikimedia Commons |
For instance, peroneal tendinopathy is a condition seen with runners, especially when they increase mileage. Pain is usually seen in the region of BL-62, is worse with activity, and is often reproduced with plantar flexion and inversion of the ankle which stretches the peroneal tendon, though sometimes eversion causes pain as it engages the peroneals. This condition might be treated locally with acupuncture by threading the tendon around the BL-62 region. In addition, the peroneal MPs should be used (the peroneus longus MP is about 1 cun directly below the fibular head). In addition, excess tension observed in the biceps femoris, the erector spinae, or even the suboccipital muscles might be used to inform point selection. If a runner has excessive capital (head) extension there would be excessive shortness in the suboccipital muscles, BL-10 and/or GB-20 might be considered as useful points employing the principle of selecting points above to treat below.
 |
| Fig. 4 |
Sacroiliac dysfunction is another example where considering the sinew channels is helpful. If the peroneals were either overactive or inhibited, this could contribute to the dyfunction at the sacroiliac joint, as the peroneals would either exerts too much or not enough tension through this line. Since these muscles are involved with such things as heel strike and proper balance of the arches of the foot, treatment of the MPs of these muscles
would enhance any local treatment at the SI joint and would help relate heel strike and foot position with sacroiliac joint stability.
