Nonunions usually lead to a continuation of the pain at the site of a break, even after the initial pain of the fracture has passed.
The pain from a nonunion may last months or even years if treatment is not sought.
Causes and Risk Factors
For a fracture to heal, the bone needs to be stabilized, usually with a cast or, in some cases, surgery is required to use plates, screws or nails to stabilize the bone. The bone also needs a steady blood supply. Blood brings oxygen, healing cells and growth factors to the bone to allow it to heal. If a fractured bone is left unstable or lacks blood supply, it can lead to a nonunion.
Factors including the use of tobacco or nicotine can impede bone healing and increase the risk of nonunion. Older individuals and those with diabetes, severe anemia or a infection also face an increased risk of nonunion if they break a bone. Medications such as anti-inflammatory drugs, including aspirin, ibuprofin and prednisone, also increase the risk of nonunion, since they affect blood flow.
Nutrition can also affect the risk of nonunion, since bones need protein, calcium, vitamin C and D, and other minerals to ensure proper healing.
Some bones, such as toe bones, have excellent stability and blood flow and almost never lead to a nonunion. Other bones, such as the upper thighbone (femoral head and neck) and small bones of the wrist have limited blood supply and are at higher risk after a fracture of developing a nonunion.