Introduction:
Distraction osteogenesis for the correction of axial deformities and short lower limbs is a long-term process which adversely affects the functional state of the locomotor system and the child's emotions. Therefore, the aim of the study was to analyse the spatiotemporal parameters of gait, and to compare the results of treatment in children after lengthening the tibia or femur by the Ilizarov technique.

Material and methods:
The study was performed in 40 children with lower limb asymmetry treated in the Department of Clinical Orthopaedics in Sosnowiec in 2000–2006. Each child was subjected to osteodistraction treatment using the Ilizarov technique. The subjects were divided into two subgroups: group 1 consisted of 20 children who had Ilizarov tibial lengthening, and group 2 consisted of 20 children who had Ilizarov femoral lengthening. Gait analysis was carried out using a dedicated system from Zebris, in which the patient is expected to walk along an approx. 2-metre long marked trajectory. The treadmill platform responded to the load, which enabled evaluation of the ground reaction force and the spatiotemporal parameters of gait. After completing measurements, the system produced a report with values of the tested parameters.

Results:
The study shows that both in children with a lengthened femur or tibia, three of the five subphases of the stance phase in the operated on limb and unoperated on limb were longer, and two shorter as compared to the normal values reported by J. Perry. The subphases of initial contact, loading response and midstance were longer, while the terminal stance and preswing were shorter.

Conclusions:
In children with a short lower limb treated with the Ilizarov technique, a better outcome was achieved after lengthening the femur compared to the tibia. The gait cycle in children after limb elongation is different from normal.