GENERAL
Description:
Our bodies are made up of 206 bones, which are lined with a tissue called cartilage, connected to bones with ligaments, and connected to other bones with tendons. The skeletal framework protects the body and supports it from gravity. There are two main bone tissues that make up the bone. Compact bone is packed tightly and contains blood vessels. Spongy bone is less dense and contains red bone marrow which produces blood cells and yellow bone marrow made of fat. Its structure is made of trabeculae which are organized in a way to maximize strength. Three types of cells compose bones: osteoblasts force cells, osteoclasts resorb bones, and osteocytes mature cells.
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There are three types of joints that determine the mobility of bones. Synarthroses do not move and are close in contact. They include the skull. Amphiarthroses are slightly movable, are connected by cartilage, and include the joints between the vertebrae and intervertebral disks. Diarthroses are moveable joints, are the most common, and there is a joint cavity between them enclosed with a capsule with synovial fluid inside.
Diseases and Conditions
Osteoporosis
As one ages, bones will weaken, making them prone to breaking. The bones will also lose mass and are caused by the loss of homeostasis between osteoclasts and osteoblasts. People with osteoporosis tend to have calcium or Vitamin D deficiency and can make individuals prone to fracturing.
Osteonecrosis
​If one uses steroids, it is possible that bone cells and tissues will die out from the lack of blood.
Osteoarthritis (OA)
Breakdown of cartilage leads to stiffness and pain in the joints. It is thought to be caused by stress and inflammation, which lets bone rub against one another, which is painful.
Rheumatoid Arthritis
Autoimmune disease at the joints which can deform them and cause swelling.
Paget’s disease
Enlarged or misshapen bones caused by a lack of vitamin D. It tends to occur in localized bones and like osteoporosis, is caused by bone resorption levels being too high.
Osteopenia
Bone density is low, contributing to a possible fracture.
Osteomyelitis
​Infection of a bone due to pathogens that may occur after surgery. It leads to swelling and requires either antibiotics or removal.