 Hey everybody, Dr. Rowe here. In this video I want to cover the muscles of the upper back, but the sternocleidomastoid sternum had an interface, so we have to look at that one as well. So let's go and start with the sternocleidomastoid. Clinically it's often called the SCM, but in school you have to call it the sternocleidomastoid. Remember sternom means sternum, collido means clavicle, so it originates on the sternum and clavicle, inserts on the mastoid process of the temporal bone, flexes your neck if both are contracting. If one is contracting, let's say my left SCM or sternocleidomastoid is contracting, it will turn my head to the right. So rotation if one contracts, flexion if they both contract. Then we have the trapezius. You can see it way better on the next image, but the trapezius, its general function is to move the scapula, but let's go into detail of the three parts of the trap when you can see it better. Then you also can see here the levator scapulae. You'll see it as well in the next image, but it elevates the scapula and also can rotate it, downward rotate it by pulling up on that corner. Levator scapulae, I used to do a lot of muscle work when I worked with athletes and a lot of times people think their traps get real tight, but the levator scapula is the muscle that I would generally have to do the most work on. So it feels, they're real similar, they're in the same area, but levator scapulae whether you know what it's called or not, chances are it's tight on you, especially if you don't have good posture and it needs a good massage or mouth fascial release or something. All right, so here you can see on the back a lot better view. So the trapezius, we said in the overview video it just moves the scapula, but now we're going to look at the three parts. There's the upper trapezius, the middle trapezius and the lower trapezius. So really functionally it should be treated like three separate muscles. They have different actions. So the upper trapezius, it's job is to elevate the scapula. So like if you're doing like upright rows or something like this in the gym, you're strengthening the upper trapezius by bringing your scapulae up. The middle trapezius right there in the middle as you can see the fibers run horizontal so they're going to retract the scapula as I squeeze my shoulder blades together. And the lower trap, it's job is to depress the scapula, like raising your hand and then trying to pull your scapula down towards your spine. That would be the lower trap. So that's the upper, middle and lower trapezius muscles, sir. It's one muscle, but we do, I want to functionally treat them like three. Then we have the rhomboid major and minor. They're named after their rhomboid shape. For those of you that remember your math and their job is also to retract the scapula. So squeezing the two shoulder blades together, levator scapula or scapula you can see there. And then also that downward rotation of the scapula and then on the left you can see the deltoid. Deltoid is shaped like a triangle where the name comes from and its job is to abduct the shoulder bringing your arms up away from your body. Okay. So those are all the key muscles of the upper back. I hope this helps. Have a wonderful day. Be blessed.