Med-Surg - Musculoskeletal System, part 1: Introduction, Anatomy/Physiology Review

Hi. I'm Cathy with Level Up RN. This is the first video in our medical-surgical nursing musculoskeletal system playlist. And throughout this playlist, I will be following along with our medical-surgical nursing flashcards, which are available on our website LevelUpRN.com. So this video playlist and our flashcard deck are intended to help you learn the most important facts and concepts you need to know to be successful in nursing school and in your nursing practice. If you do have our flashcards, be sure to pay close attention to the bold, red items on those flashcards because those are going to be particularly important facts for you to know. Also, these video playlists and these cards are helpful for both RN students as well as PN students. So if you are a practical nursing student, just keep in mind your scope of practice. At the end of this video and at the end of all the other videos in this playlist, I'll be giving you guys a little quiz to test your knowledge of some of the key information I'll be covering in this video. So in this video, I'll be doing an anatomy and physiology review of the musculoskeletal system. And then in my next video, we will talk about diagnostic tests for the musculoskeletal system.

Key functions of the musculoskeletal system include movement, structural support, protection of your internal organs, blood cell production, and storage of minerals.

The components of the musculoskeletal system include bones as well as joints. So this is where two or more bones come together to allow for movement.

So an example of a joint would be your shoulder or your knee, which are examples of synovial joints, which we will be talking more about here in a minute.

Other components of the musculoskeletal system include skeletal muscles, as well as tendons, which attach muscles to bones, and ligaments, which attach bones to bones. So if you could remember the phrase bones like bones, then that will help you remember that bones are attached to other bones through ligaments because L for likes and L for ligaments. Here's an illustration of a long bone from our medical-surgical nursing flashcard deck.

The outer layer of the bone is the cortex, which is made up of dense, compact bone tissue.

The inner layer of the bone is comprised of spongy bone tissue, and it contains bone marrow, which is where hematopoiesis occurs, which is the formation of blood cells.

So we have the red bone marrow here in the upper epiphysis, and that contains stem cells that will become red blood cells, white blood cells, or platelets.

Then we have the yellow bone marrow here in the diaphysis, which contains stem cells that will become cartilage, fat, or bone. So this line here that separates the epiphysis from the diaphysis is the metaphysis, which contains the epiphyseal plate or the growth plate.

Bone remodeling is a continuous process based on the activity of osteoblast, which are bone-forming cells, and osteoclast which are bone-destroying cells.

So we have a little cool chicken hint here on the card. Osteoblast equals bone building. So when you see B for blast, think bone building.

There are a number of minerals and hormones to be familiar with that affect bone growth.

So calcium and phosphorus are essential minerals that are needed for bone formation.

Vitamin D is needed for absorption of calcium. So if someone's taking in enough calcium, if they don't have enough vitamin D, then that calcium is not going to be absorbed readily.

Parathyroid hormone or PTH is a hormone produced by the parathyroid glands. And PTH will bring calcium out of the bones and into the bloodstream. So it will increase blood calcium levels.

Calcitonin is a hormone that counteracts the activity of PTH. So calcitonin will tone down those blood calcium levels, and it does this by inhibiting the activity of osteoclast, which are those bone destroying cells. It also decreases reabsorption of calcium at the kidneys. So again, calcitonin is going to tone down blood calcium levels. And PTH is going to increase those blood calcium levels.

And then growth hormone will increase bone formation. So it will stimulate the activity of osteoblast, which are those bone-building cells.

All right. Let's now take a look at a joint and talk about the different components of a synovial joint. Here's an illustration of a synovial joint from our medical-surgical nursing flashcard deck. So a synovial joint is a freely movable joint such as the elbow or the knee.

And you can see that we have the joint capsule, which surrounds that synovial joint and is comprised of fibrous connective tissue.

Then we have the synovium here, which is a membrane that lines the joint capsule and secretes synovial fluid, which helps to provide lubrication and shock absorption at that joint.

The joint cavity here is fluid filled, and it is where the articulating surfaces of the two bones come in contact with each other.

And we have this articular cartilage, which lines the surface of each of the bones in the synovial joint. The purpose of this articular cartilage is to allow the bones to glide smoothly against each other. We will be talking about osteoarthritis in another video in this playlist, which is caused by the wear and tear of this articular cartilage.

All right. It's time for your first musculoskeletal system quiz. I have four questions for you. They are fill-in-the-blank questions.
Question number one. Blank attaches bones to other bones. The answer is ligaments.
Question number two. Blank attaches muscles to bones. The answer is tendons.
Question number three. Bone-forming cells are called blank. The answer is osteoblasts.
Question number four. Bone-destroying cells are called blank. The answer is osteoclast.

Okay. I hope this video has been super helpful. And if so, be sure to leave me a comment. I love to hear comments from nursing students or nurses who watch my videos and find them of value. Take care and good luck with studying.