Gait analysis in patients with achondroplasia after lengthening of the lower limb segments

Purpose. To analyze the gait in patients with achondroplasia after the lower limb lengthening. Materials and Methods. 63 patients with achondroplasia at the age of 6-18 years examined before treatment, during limb segment lengthening and in the immediate (3, 6 months) and long-term (12, 24, 36 months) periods after the fixator removal. The procedure of limb segment lengthening performed monoand bilocally by the technique of transosseous distraction osteosynthesis. Results. The gait analysis demonstrated that patients with achondroplasia before treatment had relatively a short stride, the low values of walking speed, daily locomotor activity, thereby determining a low rate of walking. Ultrasound control during leg lengthening allows identifying the critical structural condition of muscles determined as «the effect of frosted glass» accompanied by a long rehabilitative period. The gait parameters determined by the range of motions in the joint in the long-term periods after lengthening. In all the patients after femur and leg lengthening the disorder of gait symmetry registered more towards the limb side where femur lengthening made at the last stage with the increase in stride variability. The forceand time-related parameters of stride cycle approached to the norm for leg lengthening up to 10 cm. The decrease in force-related parameters of stride cycle conforms to the reduction of range of motions in the joints for 12-14-cm leg lengthening. Due to the decreased angle between the foot axis and the body movement direction, the altered structure of foot rolling through the support surface persists on account of non-participation of the medial foot structures in the support. Conclusion. The studies and the results allow correcting the lengthening value in order to normalize the walking process in patients with achondroplasia.