[Changes in the wrist joint in spontaneous course of scaphoid pseudarthrosis]

Scaphoid non-union always leads to carpal arthrosis. What is the natural history and course and sequence of development of arthrosis in scaphoid bone pseudarthrosis and what factors play a role in this? Forty-nine patients with scaphoid non-union were followed up; the period of observation was between three and 39 years. For comparison, 55 patients in whom a Matti-Russe reconstruction had been carried out successfully in the same period were followed up. Both the clinical and the radiological appearance seemed to be better in the operated patients than in the unoperated patients. The time factor, the position and form of the fracture appeared to be crucial for the development of arthrosis. No patient was free of arthrosis after ten years. The arthrosis begins in the radial part of the radiocarpal joint and progresses to the mediocarpal joint. The development of mediocarpal arthrosis takes about 20 years. Unstable and displaced fractures accelerate the development of arthrosis. Proximally located non-unions are unfavorable because of the danger of osteonecrosis of the proximal fragment. These non-unions should be treated surgically as soon as possible.