Gait symmetry improves in childhood--a 4-year follow-up of foot loading data.

Children under 10 years of age are less efficient than adults regarding their dynamic balance control. The development of the somatosensory system is necessary for the control of posture and balance. The foot, as the final link between body and ground, transfers internal forces during gait. The coordination of force transfer needs to be balanced between both feet thus leading to a potential asymmetry of foot loading. The magnitude of asymmetry in infants' gait has been previously studied. However, the individual development and improvement of gait symmetry should also be considered. Therefore, the aim of this study was to retrospectively evaluate the longitudinal development of foot loading symmetries from the onset of independent walking. Sixty-two healthy infants were followed over the course of 4 years by means of plantar pressure distribution measurements (mean age of 15 months at study start and 63 months at the end). The subjects attended a total of nine measurements scheduled every 6 months. Foot loading data was recorded during walking with the emed(®) pressure platform to evaluate contact area, peak pressure, force-time integral, relative maximum force and contact time. An absolute symmetry index was calculated for all parameters. Furthermore, the infants' data were compared to the data of 26 healthy adults. The adults were measured once and the data acquisition followed exactly the same procedures as the infants' data. In conclusion, foot loading is asymmetric with the onset of independent walking and shows improved symmetry with increasing age dependent on the foot loading parameters.