Causes of bone fractures can include: Traumatic incidents such as sporting injuries, vehicle accidents and falls Conditions such as osteoporosis and some types of cancer that cause bones to fracture more easily, meaning even minor trauma and falls can become serious.
Fractures are different from other injuries to the skeleton such as dislocations, although in some cases it can be hard to tell them apart. Sometimes, a person may have more than one type of injury. If in doubt, treat the injury as if it is a fracture.
The symptoms of a fracture depend on the particular bone and the severity of the injury, but may include: Pain Swelling Bruising Deformity Inability to use the limb.
Different types of fracture include: Closed (simple) fracture – the broken bone has not pierced the skin Open (compound) fracture – the broken bone juts out through the skin, or a wound leads to the fracture site. Infection and external bleeding are more likely Greenstick fracture – a small, slender crack in the bone. This can occur in children, because their bones are more flexible that an adult’s bones Hairline fracture – the most common form is a stress fracture, often occurring in the foot or lower leg as a result of repeated stress from activities such as jogging or running Complicated fracture – structures surrounding the fracture are injured. There may be damage to the veins, arteries or nerves, and there may also be injury to the lining of the bone (the periosteum) Comminuted fracture – the bone is shattered into small pieces. This type of complicated fracture tends to heal more slowly Avulsion fracture – muscles are anchored to bone with tendons, a type of connective tissue. Powerful muscle contractions can wrench the tendon free and pull out pieces of bone. This type of fracture is more common in the knee and shoulder joints Compression fracture – occurs when two bones are forced against each other. The bones of the spine, called vertebrae, can have this type of fracture. Older people, particularly those with osteoporosis, are at higher risk.
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Mitosis is the part of the cell cycle in which the duplicated genetic material (chromosomes) within the parent’s cell nucleus is separated to produce two daughter cells that are genetically identical to the parent. Mitosis is important to life because it is involved in the production of new cells for growth and to replace damaged cells. Mitosis occurs in five stages which are; interphase, prophase, metaphase, anaphase and telophase (cytokinesis).
