Bone Growth, Diseases, and Fractures

Formation of Bones Called ossification Can then grow longitudinally and horizonatally

Cells Involved in Bone Growth Osteoprogenitor cells Osteoblasts Osteocytes Osteoclasts

Osteoprogenitor Cells Nonspecialized cells that can turn into other cells as needed

Osteoblasts Actually form the bones by secreting of calcium and other minerals

Osteocytes Mature bone cells

Osteoclasts Tears down bone and help move calcium and minerals into the blood

Endochondral Ossification Shaped cartilage is replaced by bone as a child grows older

Bone Development Cartilage bone forms Periosteum surrounds it and the cartilage beings to break down Spongy bone is created by osteoblasts Compact bone replaces the spongy bone Spongy bone reforms within compact bone

Epiphyseal Plate Growth Plate Band of cartilage that allows for continued growth until it becomes ossified

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 break down prematurely 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

Types of Bone Fractures

Hairline Fracture Fine, fracture that does not completely break the bone

Simple Fracture Also known as a closed fracture A break without a puncture to the skin

Spiral Fracture When the bone is severely twisted

Greenstick Fractures Incomplete breaks Often occurs in children because they have softer bones than adults

Compression Fractures When a bone breaks due to increased pressure

Comminuted Fracture Bone is crushed to the point that it becomes fragmented

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 Blood clots and forms a fracture hematoma Helps stabilize the bone and line it up for mending Fracture hematoma is strengthened by collagen and becomes a soft callus Osteoblasts produce bone cells to form a bone callus Osteoclasts and osteoblasts work together to replace bone callus with harder compact bone