The quantitative description of distraction regenerated bone for lengthening and the correction of posterior and middle foot deformities by the data of computer tomography (CT). Transosseous osteosynthesis according to Ilizarov was performed for the purpose of correcting posterior foot deformities in patients with deformities and developmental anomalies of foot bones. CT-characteristic of distraction regenerated bone after device dismounting has been studied in 13 patients. CT of distraction regenerated bone allowed to study the density of distraction regenerated bone in different periods after treatment. Depending on the length of distraction and fixation with the device, the density of regenerated bone varied from 25-38 HU to 50-80 HU. To solve the problem of additional fixation length, a technique for its prediction has been proposed by us. The zones of regenerated bone with density values of 70- 80 HU and higher can be considered as zones of high mineralization; those with density values of 60-70 HU – as zones of good mineralization; those with density values of 50-60 HU – as zones of satisfactory mineralization; and the zones with density values below 50 HU – as zones of unsatisfactory mineralization, thereby determining the length of additional fixation.