Prognosis of limb length discrepancy in children affected by congenital abnormality remains a subject of concern. Therapeutic strategy must take length prediction into account in order to adapt equalization techniques and the timing of treatment. Initial prognosis, however, may need revising after completion of one or several surgical interventions on the pathologic limb. The aim of this study was to determine different types of growth response that a bone segment can present after progressive lengthening in case of congenital limb length discrepancy. Materials and methods. Treatment results were analyzed in 150 patients with congenital lower limb length discrepancy, who underwent surgery at age from 2 to 15 years old. Bone segment growth rates were measured before lengthening, during the first year after frame removal and, finally, over long-term follow-up, calculating the ratios of radiological bone length to the number of months between two measurements. Mean follow-up was 5.1±1.3 years. Results. Changes in short- and long-term growth rate distinguished five patterns of bone behavior after lengthening, ranging from growth acceleration to total inhibition. Discussion and Conclusion. These five residual growth patterns depended on certain factors causing acceleration or, on the contrary, slowing down of growth: age at the lengthening surgery, percentage of lengthening and minimal period between two lengthenings. These criteria help to optimize conditions for resumed growth after progressive segmental lengthening, avoiding conditions liable to induce slowing down or inhibition, and providing a planning aid in multi-step lengthening programs. Keywords: Congenital lower limb length discrepancy, bone lengthening, residual growth