The damaged carpal bone most likely to result in Carpal Avascular Necrosis is the scaphoid bone. This may happen following a trauma and fracture to the scaphoid. Because the scaphoid bone has only one small artery that enters it near the base of the thumb, a fracture that tears the artery severs the blood supply. If not immediately diagnosed, this loss in blood supply can cause the bone to die – making union unlikely and surgery necessary.

Diagnosis
While the initial X-ray of these conditions may not always reveal an environment conducive to or presence of avascular necrosis, progressive pain and tenderness will eventually prompt another – as bone density and shape begin to change. In advanced stages, fragmentation and collapse occur and degenerative arthritis is the end result.

Treatment
Treatment of these Navicular Avascular Necrosis conditions depends on the condition of the bone, though early diagnosis increases the success of the treatments. In the early stages, intermittent immobilization may be recommended in order to allow reconstitution of normal bony structure. A removable cast may also be used in conjunction with range of motion exercises and targeted rehabilitation.

In advanced stages of these conditions, surgery is necessary.