Bone fractures

A broken bone or bone fracture occurs when a force exerted against a bone is stronger than it can structurally withstand.

Bones are a form of connective tissue, reinforced with calcium and bone cells. Bones have a softer centre, called marrow, where blood cells are made. The main functions of the skeleton include support, movement and protection of vulnerable internal organs.

Symptoms
The symptoms of a bone 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
The different types of bone fracture include:

• Greenstick fracture – the bone sustains a small, slender crack. This type of fracture is more common in children, due to the comparative flexibility of their bones.
• Comminuted fracture – the bone is shattered into small pieces. This type of complicated fracture tends to heal at a slower rate.
• Simple fracture – or ‘closed’ fracture. The broken bone hasn’t pierced the skin.
• Compound fracture – or ‘open’ fracture. The broken bone juts through the skin, or a wound leads to the fracture site. The risk of infection is higher with this type of fracture.
• Pathological fracture – bones weakened by various diseases (such as osteoporosis or cancer) tend to break with very little force.
• 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, are prone to this type of fracture. Elderly people, particularly those with osteoporosis, are at increased risk.