[Spinal pseudarthroses].

Pseudarthroses of the spine are classified into congenital, acquired non-traumatic, posttraumatic and postoperative (iatrogenic) pseudarthroses. The various types of non-unions of the spine are described according to their clinical and radiological appearance. In line with their clinical importance, special attention with respect to the operative treatment is given to non-union of the axis of C2 and to spondylolysis. For the pseudarthrosis of the dens a posterior fusion according to Gallie-Brooks is recommended, in spondylolysis without marked slipping a "direct repair" should be considered in young patients.