In 1911 Preiser described the avascular necrosis of the scaphoid bone, which is regarded as a relatively rare clinical and radiological condition. The diagnosis is not established easily, and a small, avascular proximal fragment, e.g. in a scaphoid pseudarthrosis, should not be confused with Preiser's disease. Two histologically diagnosed cases are described: one of thema at operation 42-year old woman received a scaphoid Swanson implant in 1980. At follow-up eight years later, she presented with very satisfying clinical and radiological findings.