Structure of Ligaments and Intervertebral Discs (Nursing)

00:01 The vertebra really needs some very strong ligaments to help keep them together and provide structural support.

00:08 So there's actually a lot of ligaments that connect the various vertebra.

00:13 Anteriorly along the anterior aspect of the bodies, we have something called the anterior longitudinal ligament.

00:21 Similarly, we have a posterior longitudinal ligament running along the posterior aspect of these vertebral bodies.

00:29 Another thing you might not think of as being a ligament and we're going to talk about in greater detail in just a little bit are the intervertebral discs that lie directly between the vertebral bodies.

00:42 If we go a little bit further back, we have ligaments that connect to the various lamina of the vertebral arches.

00:52 And they actually look kind of yellow.

00:55 And that's actually why they're called ligamentum flavum, flavum means yellow.

00:59 And they have this yellow color because they have a lot of elastin fibers that in part of the yellowish hue.

01:06 Because this ligament is connecting the lamina which is part of the posterior aspect of the vertebral column.

01:14 We have to go through that with a needle when ever we want to reach the spinal cord and take spinal fluid during a lumbar puncture.

01:24 And if we look at the spinous processes, we see that there are ligaments that connect adjacent spinous processes called interspinous ligaments.

01:34 But all the way at the posterior tip of those spinous processes, it's one long continuous ligament called the supraspinous ligament.

01:44 That by the time reaches the cervical area broadens become the nuchal ligament with nuchal meaning neck or cervical area.

01:54 So let's go back to those intervertebral discs we briefly mentioned.

01:58 So as the name implies, they're in between the vertebra and they're disc-shaped structures that basically support and separate and connect adjacent vertebral bodies.

02:10 So here's an example from a superior point of view of an intervertebral disc.

02:17 And it has two main parts, an outer annulus fibrosis, which is very tough hence the term fibrosis.

02:25 Fibrotic is usually a tough type of connective tissue.

02:29 And then an inner nucleus pulposus, which has much more fluid inside it and is much softer and acts more like a shock absorber.

02:41 So again, here we have that superior view, outer annulus fibrosis inner nucleus pulposus.

02:48 That annulus fibrosis is composed of something called fibrocartilage.

02:53 It's a special type of cartilage there's a lot stronger than other types of cartilage.

02:59 And it gives that strength and stability to the vertebral column.

03:04 The inner portion or nucleus pulposus, just like the nucleus of a cell is in the middle of a cell has a lot of mucopolysaccharides and proteins and more water in fluid in it.

03:18 And that gives it sort of a more resilient nature.

03:21 And that's really more of a shock absorbing function of the intervertebral discs.

03:27 Now these discs are doing a lot, providing strength, stability and shock absorption.

03:33 And normally, they're going to be doing all of that without any problem.

03:38 Unfortunately, over time, particularly the nucleus pulposus can dehydrate and lose its ability to be a shock absorber.

03:47 The annulus fibrosis with wear and tear can start to degenerate and you can get degenerated discs.

03:55 And when that happens, it can start to bulge outward.

03:58 And if it does that posteriorly, it's going to run into spinal nerves exiting the spinal cord in that area.

04:06 Sometimes, the fibrosis portion can break and the nucleus pulposus can squeeze out because it's so soft and malleable, something called a herniated disc and also pinch on nerves.

04:19 As I mentioned over time, that resilient inner layer, the nucleus pulposus loses water, it dehydrates and it gets thin.

04:26 And now two bones can get very close to each other and rub against each other.

04:32 And that's essentially arthritis or osteoarthritis.

04:37 And when that happens, it creates this new abnormal bony growth at the edges called osteophyte formation.

04:45 And so that actually is a nice reminder that we do have the spinal cord and spinal nerves nearby all throughout the course of this vertebral column.

04:54 So a normal disc is going to stay well out of the way of any of our spinal nerves.

05:01 But like I said, with a lot of wear and tear, you might develop something called a herniated disc where the annulus fibrosis is so damaged that the nucleus pulposus, which is soft and malleable, can squish out and start compressing that nearby nerve causing pain and numbness in the distribution of that spinal nerve.