Objective
To investigate the effects of dynamic (hinged) and solid ankle-foot orthoses (AFO) on the gait characteristics in spastic cerebral palsied children and to find out which AFO has a more beneficial effect on correcting the abnormal gait pattern in those children.

Method
The subjects were 40 children with spastic cerebral palsy (CP) who were able to walk independently without walking aids. Their ages were ranging from 2 to 12 years. Children were randomly prescribed to dynamic or to solid AFO. Twenty-four children got solid AFO and 16 children got hinged AFO. Gait characteristics were evaluated by computer based kinematic gait analysis while they were walking with AFO and on barefoot. Gait characteristics on barefoot and with hinged AFO and with solid AFO respectively were compared.

Results
Temporospatial parameters while walking on barefoot were not significantly different from those while walking with AFOs. While walking with hinged AFO, the maximal knee extension angle during stance phase was decreased in comparison with that on barefoot (p＜0.05). Ankle dorsiflexion angle on hinged AFO was increased throughout the gait cycle (p＜0.05). While walking with solid AFO, ankle dorsiflexion angle at initial contact, at 98% of gait cycle and at maximal ankle dorsiflexion angle in stance phase were increased in comparison with that on barefoot (p＜0.05). There was no significant difference of changes after wearing orthoses between hinged and solid AFO.

Conclusion
Both types of AFOs exerted a positive effect on ankle motion, not in knee or hip joints in the children with spastic cerebral palsy. The gait characteristics during walking with both AFOs were not significantly different, even if the hinged type might be more effective in preventing knee hyperextension in stance phase and in improving maximal ankle dorsiflexion during the swing phase.