Reflections from the Cadaver Lab: Week 1 Day 4

Reflecting on my fourth day teaching this year's Cadaver Lab.

Day four of lab is really the point where you start to get into the channels. This happens a bit on day two and three also, but four is much more obvious. We are going more into the neurovascular and myofascial structures, but you are also evicerating. This current class is for Physician Assistant students, so I don't discuss the channels much, but they are always in my mind and here are some anatomical thoughts on the channels that I was observing today.

1. The greater omentum gives us a view of the Lung channel. Look at the image of this channel in Deadman (or, really any good illustration) and also follow the description and you will see that this channel originates in the region of the stomach and then descends and connects with the large intestine. This is exactly what the greater omentum does. It hangs off of the greater curvature of the stomach and drapes over the abdominal organs. If you lift the bottom of this structure upwards to look at the under surface, you see that this anchors the transverse colon. There is a really interesting physiological thing that connects this structure to the Lungs (capital L meaning that I am discussing the TCM view of the Lung). The greater omentum can move and cover assist when there is infection on the abdominal cavity. It has been described as the abdominal policeman since is has an immune system cells and it surveils the region, mobilizes and covers areas of infection and walls it of with immunologically active tissue. Sounds a bit like wei qi to me!

2. On the topic of the Lung channel, I was able to get a really great view of the Lung sinew channel. I was demonstrating dissection of the anterior forearm muscles and preparing for reflection of the superficial muscles such as the palmaris longus, flexor capri radialis, and ulnaris. The arm was up overhead to expose the anterior forearm. Removing crosslinks from the ulnar surface of the FCR keeps the lacertus fibrosis (bicipital aponeurosis) intact and you can see such an obvious fascial plane between FCR and the biceps brachii. I pointed out the myofascial plane which interested the students, but I think my acupuncture colleagues would have appreciated it much more.

3. Another channel I observe when working with a student was the Liver channel and a branch of the Stomach sinew channel. I was helping the student reflect back the quadricep group from the innominate and femur, but keeping them intact as a group and keeping the patellar ligament intact. This requires going medial/under the IT band to remove the vastus lateralis from the linea aspera and other femoral attachments. And it requires going lateral to the medial intermuscular septum of the thigh (the septum between the vastus medialis and adductors) to remove the vastus medialis from the linea aspera and other femoral attachments. Then it requires lifting all of the quadriceps off the femur. When entering into the medial intermuscular septum, you are in the Liver channel. As you follow this space proximal, you end up between the vastus medialis on one side and the distal iliopsoas on the other. You are also in very close proximity to the neurovascular structures in the femoral triangle.

   When you do this on the lateral side, you are cutting the vastus lateralis away from bone. This is a muscle of the Stomach sinew channel. At its most proximal, you need to cut this muscle away from fibrous attachments to the glutes. This is the lateral branch of the stomach sinew channel which is said to connect with the shaoyang channels. It then runs up the gluteus medius and minimus fascia to connect with the lateral raphe, a structure in the thoraculumbar fascia that is the lateral border of the quadratus lumborum and iliocostalis lumborum.

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