The following are common categories.

• Comminuted fractures occur when the bone fragments into a number of pieces.
• Compound fractures involve extension of one or both bone fragments piercing the skin or damaging internal organs (such as a fractured rib piercing a lung).
• Compression fractures occur when bone tissue is driven together. This type of fracture often occurs with falls in which individuals use their arms to break the fall, resulting in compression of the wrist or elbow bones.
• Depressed fractures are frequently seen in skull injuries, in which the bone is pushed into a concave position, often resulting in brain contusions, concussions, or trauma.
• Fissure fractures are commonly referred to as hairline fractures. The bone is cracked but not completely broken through—also called an incomplete fracture.
• Greenstick fractures are aptly named since the bone is not broken but, rather, bent and is still in one piece. This type of fracture is often seen in children whose bones are not yet hardened.
• Pathological fractures are caused by disease, weakness in bone tissue, or for some other nontraumatic reason. These types of fractures may occur without any unusual force, such as the deterioration and collapse of bone tissue due to osteoporosis. When pathological conditions exist, trauma to the bone may lead to more damage than might have been expected if the secondary condition did not exist. Pathological conditions may also slow or delay the healing process.