Inside Med School

Let me start by saying the first cut in anatomy is a pretty memorable experience. It’s kind of a monumental period in a career in medicine. Our first lab was titled “Dissection of the Back,” Pretty straightforward. So my first incision was a shallow incision from the back of the neck down the spine towards the lumbar region. Making that incision marked the beginning of anatomy and it gave me goosebumps while I was doing it. From then on my lab partners and I made some transverse cuts perpendicular to that first cut and started to remove the skin off her (the cadaver’s) back. That process was a little frustrating because we were all very eager to see all the muscles in the back but skinning the back was taking a lot longer than we thought it would. It’s more tedious to remove skin from a cadaver with a lot of subcutaneous fat, and the groups who had skinny cadavers were just flying through this process and exposed their muscles with ease.  It also was taking a while because we weren’t sure how deep to cut under the skin because our cadaver had a lot of bruising and we weren’t sure if we were still in fat, or if we were cutting into muscle. Another thing that surprised me was how tough skin is. To pull back the skin they advised us to make a slit in the flaps we created, stick our fingers in it and use it to pull back on the skin while we use the scalpel to cut the connective tissue holding it down. I was surprised how tough the skin was, because by the end of it I was really pulling hard on that skin to get more tension and the initial slit I made stayed about the same size.

Any ways, eventually we removed the skin and reflected the flaps out of the way so we could start observing the muscles.  So at first I thought it was a little overwhelming to have our first lab be the entire back. However, once we exposed it I could see why they wanted us to start from here. The muscles in the back are pretty big, and there aren’t that many of them so it’s a great place for beginners to start because you don’t have to be that delicate. I think a lot of people would be familiar with the superficial muscles of the back especially if you like to lift weights. So it was nice to see them up close. I remember thinking they were a lot thinner than I thought they would be. After we identified all the shallow muscles, we cut them from their attachments to the spine and reflected them back to reveal the muscles underneath, and observe the nerves that innervate them.

Once we looked at all the shallow and deep muscles we got down to the fun part, exposing the spinal chord! So to expose the spinal chord you have to cut away a section of muscle around several vertebrae in the back. Then you have to remove the spinous process of the vertebrae (the part that sticks directly out, you can feel them when you rub your fingers down your spine.) To remove the spinous process you have to use a hammer and chisel! It was pretty crazy because earlier I was being very delicate and trying not to cut any muscle tissue, then a few minutes later we cut away a chunk of muscle and were using chisels to crack open bone! It’s a pretty quick transition. Any ways once you chisel away the top portion of the vertebrae you can pull them off to reveal the spinal chord. From there we cut the dura matter, which is a sac that covers the cord, and exposed the actual spinal chord and the nerves that extend out of it and throughout the body. It was pretty amazing to see it up close and personal. We exposed a section of the spine from the 12^th thoracic vertebrae to about the 4^th Lumbar vertebra. That’s about the region where the spinal chord ends (it ends at about Lumbar vertebra 1-2.) Long nerves that extend down to the lower vertebrae innervate the rest of the back. A fun fact is that usually spinal taps or epidural needles are given at the location of lumbar 4 to avoid accidently puncturing the spinal chord. Also getting a gunshot wound below L1 is better than anywhere above it because the bullet will pass below the spinal chord and you have less chance of paralysis. That’s about it for our first lab. For a recap , we skinned the back, observed several layers of muscles, identified some nerves, and exposed the spinal chord. Pretty cool, for our first lab huh? I’m going to study a little now, and then fill you in on some more highlights from anatomy during my next break. Stay tuned!