A sprained wrist is commonly diagnosed after a patient falls on an outstretched hand. However, if pain and swelling does not go away, surgeons become suspicious that the injury is actually more serious.
The wrist is made up of eight separate small bones, called the carpal bones. The scaphoid bone is a carpal bone near the base of the thumb. A fall onto an outstretched hand commonly breaks the scaphoid bone of the wrist.
This stress can cause either a small crack through the middle of the bone or a complete separation of the bone into two pieces. A separation is called a displaced fracture.
When a scaphoid fracture is recognised on the first x-ray, treatment begins immediately. But patients often assume that the injury is just a sprain, and they wait for it to heal on its own. In some cases, the wrist gets better. In many cases the bone fails to heal. The scaphoid fracture then develops into what surgeons call a non-union. A non-union can occur in two ways. In a simple non-union, the two pieces of bone fail to heal together. The second type of non-union is much more serious. The lower half of the fractured bone loses its blood supply and actually dies. This condition is called avascular necrosis.
The symptoms of a fresh fracture of the scaphoid bone usually includes pain in the wrist and tenderness in the area just below the thumb. You may also see swelling around the wrist. The swelling occurs because blood from the fractured bone fills the wrist joint.
Symptoms of a non-union of the scaphoid bone are more subtle. You may have pain when you use your wrist. However, the pain may be very minimal. It is fairly common for surgeons to see a non-union of the scaphoid bone on x-rays, but the patient cannot remember an injury. The most common symptom of a non-union is a gradual increase in pain.
If the fracture is identified immediately and is in good alignment, you will probably wear a cast for 9 to 12 weeks. Your surgeon will take x-rays at least once a month to check the progress of the healing. Once your surgeon is sure the fracture has healed, the cast will be removed.
A fracture that doesn't heal within several months is considered a non-union. If the injury is fairly recent, your doctor might recommend more time in the cast and/or prescribe an electrical stimulator (a device which accelerates the healing process).
If non-surgical treatment is unsuccessful you may then have to have an open reduction and internal screw fixation of scaphoid non-union or your surgeon may perform open reduction and internal fixation using a bone graft.