Download - December 12, 2014 Journal: What is the difference between a ball and socket joint and a hinge joint?
December 12, 2014
Journal: What is the difference between a ball and socket joint and a hinge joint?
Bone Growth
Ossification - formation of bone in the body
Bones grow longitudinally to develop height and horizontally so they can better support our weight
Osteoprogenitor Cells
Nonspecialized cells that can turn into other cells as needed
Found in the periosteum, endosteum, and the central canal of compact bones
Osteoblasts
Actually form the bones by secreting of calcium and other minerals that give a bone its usual characteristics
Developed from osteoprogenitor cells
Bone Development
Endochondral Ossification: Shaped cartilage is replaced by bone as a child grows older
Development Before Birth Cartilage bone forms Periosteum surrounds cartilage bone and the
cartilage beings to break down Spongy bone is created by osteoblasts
Now called the primary ossification center
Compact bone begins to replace the spongy bone
Development After Birth Long bones continue to grow Secondary ossification begins with spongy
tissue forming and not breaking down Epiphyseal plate (growth plate): a thin band
of cartilage forms between ossification centers to allow for continued growthHormones control bone growthEventually growth plate becomes ossified and
growth stops
Natural Bone Deterioration As the body ages the bones and
cartilage deteriorates Total bone mass also gradually
decreases as we age as well
Osteoporosis
Disease where bone density decreases and tissues deteriorate
Causes bones to break more easily
Occurs in women four times more than men
Arthritis Inflammation of the joints Cartilage, tendons, and joints becomes
less flexible and decreases the range of motion
Scoliosis Abnormal curving of the spine which
makes it appear in a ‘c’ or ‘s’ shape instead of a straight line
Hairline Fracture
Fine, fracture that does not completely break the bone
Looks like a piece of hair on X-ray
Greenstick Fractures
Incomplete breaks Often occurs in
children because they have softer bones than adults
Compound Fracture Also known as an open fracture When the bone is pushed through the skin Deep tissues have the ability to be exposed to
bacteria and infection can occur
How a Bone Heals Bone breaks and severs the blood vessels within the bone Blood leaking out of these vessels clots to form a fracture hematoma
Helps stabilize the bone and line it up for mending Bone dies without blood and dead cells are removed Fracture hematoma develops tougher tissue and becomes a soft callus Fibroblasts produce collagen which strengthens the soft callus Osteoblasts produce bone cells which form a bone callus Osteoclasts and osteoblasts work together to replace bone callus with
harder compact bone