Reflections from the Cadaver Lab: Week 1 Day 3

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

Things really get moving on day three. The specimens are turned back to supine and we are now differentiating structures so that we can view the musculature and expose neurovascular structures such as those in the femoral triangle, anterior neck, axillary region and down into the extremities. Here are some thoughts from today.

1. Possibly the biggest roadblock people doing dissection for the first time (really, the first several times) is that, after successfully reflecting the skin and subcutaneous layer, they stop at the hands, feet, pubic area and groin, and the face. This is because these areas are more difficult to dissect and they have a complex anatomy. The problem is that, as you progress deeper, you can't follow the structures fully. For instance, if you don't reflect the skin and adipose at the groin region, you can follow the adductors to their attachments which makes it more difficult to differentiate them. Or, if you don't reflect the skin and subcutaneous tissue on the hands, you can't follow the wrist and finger flexors in the arms to their attachments, This then makes it harder to differentiate the structures which becomes more and more difficult the deep you go.

   This problem becomes apparent on day three. It is always a problem, but I have to say that the class did pretty well with this. I prepared them for the problem with a simple example. I had several shirts on and a hoody. I first took the hoody off, but kept the hood on my head and the sleeve on my right arm. In other words, I didn't completely take it off. Then I proceeded to take of the next shirt. Obviously, since the hoody wasn't removed fully, I couldn't take off the second shirt all the way. Each successive shirt become more problematic.

   I feel a similar problem can occur when working with patients. There can be a tendency to use a needle to release tension in a deep structure. But sometimes we need to unwind tension in the outer, overlying areas to allow the deep structure more room to release.

2. When differentiating structures, you start to use the scalpel to introduce more movement in the natural planes of movement. This means that you are cutting fascial crosslink between muscles along the natural sliding surfaces. One thing you immediately see is that the muscle becomes loose and floppy which causes it to sag and loose the relationship with other structures. Freeing the crosslinks between the sartorius and underlying quadriceps, for instance, cause it to sag and allows you to move it to see underneath. Seeing this over and over has changed how I work. While we don't want our patients structures to loose integrity and the need these crosslinks between muscles, I do find that I work much more in these fascial spaces, especially with manual work. Encouraging movement in these fascial spaces can have a significant impact on the movement potential of the muscles connected by these crosslinks.

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