A fractured forearm is the most common type of broken bone. It involves the fracturing of the forearm’s ulna or radius bones – or both. Radius fractures occur slightly more frequently than ulna fractures. A fracture near the wrist is also referred to as a broken wrist. Depending on the severity of the break, the forearm may be treated conservatively or surgically.
Forearm fractures are caused by an external force, usually when a person falls and tries to break their fall using their hand or forearm. When this happens, the person’s entire body weight is transferred to their arm and often that is enough to fracture one or more of the bones in the forearm. This particularly applies to older people with osteoporosis. The bone that runs along the thumb-side of the forearm (radius) is more frequently broken than the other long forearm bone (ulna). Fractures that occur near the wrist – or which involve the wrist – are referred to as broken wrists. A particular type of fracture that affects children is known as a greenstick fracture: the edge of the bone bends, but the bone doesn’t break all the way through.
A broken forearm instantly triggers severe pain, which is followed by swelling of the forearm or wrist. Sometimes there is also bruising. Displaced fractures cause the bones in the forearm or hand to become misaligned. Extreme trauma can result in an open break (compound fracture) that also damages the soft tissue and the skin.
A fractured forearm or wrist is diagnosed using x-ray imaging. Complicated breaks involving the wrist are sometimes also examined using an MRI scan.
The treatment depends on the location and severity of the fracture. Simple fractures without fragments that do not involve the wrist can be treated conservatively. After the break has been realigned, the forearm is stabilised for several weeks using a brace or plaster cast until it has healed. Complex breaks involving the wrist, comminuted fractures and compound fractures always require surgery. Find out more about the surgical treatment options in the fractured forearm surgery and broken wrist surgery sections.