The protector that keeps bones alive: What you need to know about the periosteum!

Do you think that our bones are just lifeless, hard things like rocks? While many people think that way, the truth is much different. Our bones are actually living, constantly growing, and amazing tissue that can repair itself. So, these living bones have a very special protective covering that helps them receive nutrition, blood, and even feel pain. Today, we are going to talk about this silent protector of our bones, which is the periosteum.

Simply put, what is the periosteum?

Think about the bark around a tree trunk. That bark provides the tree with many things, such as protection and nutrition, doesn't it? Similarly, the periosteum is a thin, but very strong membrane that surrounds most of our bones. It is firmly attached to the bone. Although it may seem like just a membrane at first glance, many things happen inside it that are essential for the survival of our bones.

Inside this membrane, there is a large network of tiny blood vessels and nerves . To be precise, it is the periosteum that gives life to our bones.

What benefits does the periosteum have for our body?

The service provided by this small membrane is no small feat. It has three main functions.

• 1. Blood supply to bones: As we discussed earlier, bones are living tissue. So, like any living tissue, bones need oxygen and nutrients. They also need to remove waste products that build up inside the bones. Most of the blood supply to bones for this purpose comes from tiny blood vessels in the periosteum. These blood vessels are connected to the main circulatory system of our body and help keep bones healthy.

• 2. Giving bones "feeling": Have you ever wondered how it hurts so much when a bone breaks? In fact, bone tissue itself has little ability to feel pain. But the periosteum is full of nerves. When a bone breaks in an accident, this periosteum membrane around it is torn and injured. At that time, the nerves in it are stimulated and send that signal to our brain as severe pain. That is why a bone fracture is such a painful experience.

• 3. Bone growth and repair: This is the most amazing ability of the periosteum. Inside this membrane, there is a very special type of cell. These cells can make new bone cells, called osteoblasts, when needed.
• During childhood: The bones of young children and adolescents grow rapidly. The main reason for this is that these bone-building cells in their periosteum are very active.
• In an accident: Imagine you break a bone in your hand. At that point, your doctor sets it and puts a plaster on it. Then something amazing happens inside. The special cells that have been sleeping in the periosteum around the fracture "wake up." They quickly produce new osteoblast cells, which bridge the two broken bone fragments and reconnect them. Simply put, the periosteum is the superhero that heals your bone.

Where is the periosteum located?

Almost all of the bones in our body are covered by the periosteum membrane, but there are some areas that are not covered by it.

• At the ends of bones that meet at joints (these are covered with cartilage).
• Where muscles and tendons and ligaments attach to bones.

Are there any bones without a periosteum?

Yes. There is a special type of bone in our body that is not covered by the periosteum. These are called sesamoid bones . These are located inside the muscles or tendons. The best example of this is our kneecap (patella) . Apart from that, there are also small sesamoid bones in the hands, wrists and feet.

Layers of the periosteum and other types of membranes

The periosteum consists of two main layers. This is thicker in childhood and gradually thins out as we age.

In addition to the periosteum, there are two other important membranes associated with our skeletal system. Don't confuse these.

Common conditions affecting the periosteum

Two major problems affecting this important membrane are periostitis and fractures.

Periostitis

Simply put, this is swelling or inflammation of the periosteum. The main cause of this is overuse of a particular muscle group.

Imagine that you suddenly start running for miles, or doing some tough training like in the military. Then your shins and the muscles around them are overworked. These muscles are connected to the bone through the periosteum membrane. So, due to this overuse, the membrane gets stretched, swollen, and painful. This is what we call "shin splints" in common parlance. This condition often occurs in athletes.

Periostitis can also be caused by a bacterial infection. This is a serious condition. If you have any of the following symptoms, see a doctor immediately or go to the hospital's Emergency Department (ETU):

• Severe pain in a bone.
• Pus draining from a wound.
• Presence of fever .

Bone Fractures

As we discussed earlier, a broken bone means that the surrounding periosteum is also damaged. Fractures are caused by severe accidents, such as car accidents and falls. The main symptoms are:

• Severe pain
• Swelling
• Tenderness
• Inability to move a body part that is normally movable
• Blue/purple skin discoloration
• An unusual lump or deformity

How do you keep the periosteum healthy?

There's really nothing special you can do for the periosteum. The most important thing is to keep your entire skeletal system healthy. That requires a good diet and exercise.

Also, protection from accidents is very important.

• Wear seat belts every time you ride in a vehicle.
• Wear proper safety equipment when playing sports or doing hazardous work.
• Remove and keep things in order at home and at work that could cause you to slip and fall.
• Do not climb on chairs or tables to reach for something that is above. Use appropriate equipment for that purpose.
• If you have difficulty walking or are at high risk of falling, use an assistive device such as a cane as directed by your doctor.

Although we usually think of bones as inanimate, unchanging, they are actually a living, constantly changing system. This tiny membrane called the periosteum plays a vital role in the healthy survival, growth, and healing of that system. Take care of the health of your bones. The stronger they are, the less likely you are to sustain an injury in the event of an accident.