The causes of post-traumatic deformities of the upper and lower arm shafts as well as the complete elbow are 90% iatrogenic, in the area of the proximal humerus and the distal lower arm they are about 90% the result of chance (premature closure of the growth plate). In general, corrections of deformities are possible at any age, dependent on the patient's symptoms, the expected development, the location of the deformity and its changes during development. The correction technique should allow for the removal of all of the components of the deformity, and to retain the results until healing is complete and the patient's motor stability is ensured. Due to the high percentage of iatrogenic deformities, the optimisation of the primary therapy should receive particular attention rather than increasing the indications for a correction.