Relevance Different lengths of the lower extremities have a negative impact on the position of the pelvis and spine and lead to secondary deformities. To prevent these consequences, early surgical correction of the shortening is necessary. Aim of study Study of the features of post-traumatic shortening of the lower extremities, mechanisms of adaptation to this condition and, on the basis of this, optimization of surgical technique when performing reconstructive and restorative operations. Material and methods A total of 276 patients with posttraumatic shortening of the lower extremities were examined, 102 of whom were operated on. Comparative radiography of both legs was used to diagnose different lengths. The Ilizarov method was used as the main method of surgical correction. Results We studied the mechanisms of adaptation of patients to post-traumatic shortening of the hip and lower leg and optimized surgical technique. A method was developed for determining the optimal elongation value. Conclusion The most effective and least traumatic method is external osteosynthesis according to Ilizarov. Distraction in the apparatus allows the formation of a regenerate of the required shape and length and the elongation of exactly the amount that is optimal for a given patient. © 2020 Sklifosovsky Research Institute for Emergency Medicine. All rights reserved.