You have 206 bones in your body!
These include the hammer, anvil, and stirrup, located in your ear, which are the smallest bones in the body, and the femur or the thighbone, which is the largest.
206 is not an absolute number because babies have more bones than adults. These little ones are born with around 300 bones. As they grow older, some of the bones fuse to become one. For example, you may notice the soft spots or “fontanelles” on babies’ heads. These are the spaces between bones that have yet to fuse.
206 is also not an absolute number because some folks could have extra ribs, limbs, or digits.
Speaking of which, you may have only 10 fingers, but there’s more under there than meets the eye. A single hand has around 27 bones, and the foot, 26. (Half of our bones are located in the hands and feet.) These are nicely choreographed one to another, allowing us to do a-thousand-and-one things with them—from gripping, slapping, waving, to running, jumping, and dancing.
All your bones are connected to other bones...except one. There is but one bone, the hyoid bone, that sits near the base of the skull. It is a U-shaped thing held in place by muscles and ligaments, and holds up the tongue, allowing us to open and close our jaw as well as swallow.
The skeletal system, with all its bits and pieces, provides a framework for the body, giving it structure and support.
What Do You Mean Bones Are Alive?
Even though they break every day, (the most injured part is the arm), bones are very tough to crack. They measure 5 on Mohs Hardness Scale, making them tougher than concrete. A cubic inch of bone can bear a load of 19,000 lbs. That’s the equivalent of 4 pick-up trucks!
They’re tough alright, but it doesn’t mean they are dormant. Bones are living tissues and change throughout life.
New bone tissues are continuously being created as old ones are being removed. Remodeling, maintenance, and repair are happening all the time. Especially during the time of growth.
Osteoblasts are cells responsible for building new bone tissues. They produce collagen that serves as the framework or scaffolding for the bone. Minerals (calcium phosphate) congregate around this scaffolding making the structure denser and stronger.
Osteoclasts have the opposite role. They break down bones into their components, releasing the stored minerals. The minerals (mostly calcium) are passed to the blood where it performs several vital functions. This resorption of minerals helps maintain the homeostasis of the body.
Osteoblasts and osteoclasts are working throughout life, building and breaking down bone tissue.
Because the bone continually refreshes and replenishes itself, you have a new skeleton every 10 years. Each year, 10% of your bone mass is replaced.
When you’re young, especially in your 20s, your bone density is at its peak. Meaning, more bones tissues are created than resorbed. As you grow older, your bone density decreases. The optimal state in your 20s is slowly being reversed, until such a point that more bone tissue is dissolved than is created.
When A Bone Breaks…
Because the bone is living tissue, it immediately springs into action when something bad happens, initiating healing protocols.
Let’s say a person has an accident and fell down the stairs.
When there is a clean break in the structural integrity of the bone, all the materials needed for reconstruction are immediately brought to bear. A hematoma forms. Inflammation occurs as cytokines rush to the area. Then a clot is formed around the region of the break.
Over time, this clotted hematoma is slowly cleared. At the core of the bone, tiny capillaries from both ends of the break grow into the gap between them and start “feeling” for each other until they reconnect. At the same time, on the surface, mesenchymal stem cells proliferate.
These stem cells specialize to become osteoblasts, fibroblasts, and chondroblasts. These cells will do their healing work and around the 3rd week, a soft callus forms around the break. There will be progressive consolidation in the weeks ahead until a hard callus is formed around the 2nd month until the bone is reconstructed.
All of these things happen automatically. So when a doctor puts a cast, it is to eliminate stress and movement on the break so that the bone can heal itself properly.
Of course, there are different factors at play in the healing process. One’s age, nutrition, medication, and whether one smokes or is stressed, matter.
Meanwhile, Inside The Bone Marrow…
Your bone is not dense and hard from surface to core. If you cut a cross-section of the femur, you’ll find a fatty and spongy tissue we call the bone marrow.
This soft, gelatinous is region is a factory—producing the different components of the blood.
Ever wondered where we get red blood cells? It comes from the bone marrow.
The bone marrow contains stem cells. These stem cells follow a “recipe” and can turn into three different kinds of special cells: red blood cells, white blood cells, and platelets.
Red blood cells are important because they carry oxygen throughout the body. White blood cells are the body’s defense forces, helping fight infections. And finally, the platelets prevent us from bleeding out by helping blood to clot.
The bone marrow produces them and therefore plays a vital role in health.
Bone marrow can mostly be found in the pelvis, sternum, cranium, ribs, vertebrae, scapulae, and the proximal ends of long bones like the femur and humerus.
Diseases Of The Bone
There are several bone maladies to watch for:
1) Osteoporosis
This is, by far, the most common bone disease. It is said that osteoporosis affects almost half of Americans age 50 and up—afflicting more women than men.
The condition occurs when the bones become brittle and weak as a result of decreasing bone mass and mineral density. The thing with osteoporosis is that it is a “silent condition,” having no symptoms until a fracture or break happens.
It typically involves the hip, wrist, and spine.
2) Scoliosis
If osteoporosis is an old woman’s disease (although we don’t rule out juvenile osteoporosis afflicting young individuals), scoliosis hits before puberty, before the growth spurt. It involves the “S-shaped” or “C-shaped” curvature of the spine.
Doctors and researchers can’t pinpoint the cause of the condition, but it could be genetic. The condition runs in families, and having a relative with scoliosis makes one 20% more likely to develop the condition.
3) Osteoarthritis
As mentioned earlier, all bones are connected to other bones, save for one. Osteoarthritis (OA) is the most common form of arthritis. It is a degenerative disease resulting from the wear and tear of the cartilage in the joints, the very thing that prevents bones from rubbing directly with each other.
OA affects people who are aged 60 and above, causing these members of the population pain, stiffness, as well as loss of range of motion.
Age, weight, and lifestyle are factors of this condition.
4) Primary and Secondary Bone Cancer
When abnormal cells indiscriminately multiply in an individual’s bone, it may destroy bone tissue and become primary bone cancer. The good thing though is that primary bone cancer is relatively rare and most tumors are non-cancerous and benign. Osteochondroma, which affects young people, is an example.
However, some cancers begin in the other parts of the body only to spread to the bone. This is what we call: secondary bone cancer. For example, cancer from the lung, kidney, or prostate can metastasize or spread to the bone.
5) Diseases of the Bone Marrow
The bone marrow is the factory for red blood cells, white blood cells, and platelets.
When the bone marrow produces cells that are non-functioning or come in inappropriate numbers, this usually results in a condition. For example, leukemia, also known as the cancer of the blood, is caused by the production of abnormal white blood cells.
Aplastic anemia, on the other hand, results from the marrow’s inability to produce sufficient levels of red blood cells. So it’s very important that your bone marrow functions properly
Your bones don’t only provide structure and support to the body. The bone marrow also plays a significant role in general health.
BloodWorks Lab is your one-stop shop for all your blood test needs—offering a wide range of screening, tests, and immunological and neurological assessments.
We are also proud to be the first laboratory in the Philippines to offer the Anti Acetylcholine Receptor (lgG) Antibody Test and the Anti N-Methyl-D-Aspartate Receptor (Anti NMDA Receptor) Antibody Test.
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