Effect of dynamic orthoses on gait: a retrospective control study in children with hemiplegia.

Several positive influences of orthoses on gait in children with cerebral palsy have been documented, as well as some detrimental effects. Most importantly, push-off is decreased in orthoses, compromising a physiological third ankle rocker. The aim of this study was to evaluate the effect of three types of orthosis on gait in a homogeneous group of children. All orthoses aimed at improving push-off and normalizing the pathological plantarflexion-knee extension couple. Thirty-seven children (22 females, 15 males) with hemiplegia, aged 4 to 10 years (30 Gross Motor Function Classification System [GMFCS] Level I, six GMFCS Level II), walked barefoot and with orthoses being either Orteams (orthoses with the dorsal part containing 11 sleeves), posterior leafsprings (PLS), or Dual Carbon Fibre Spring ankle foot orthosis (AFOs; CFO: carbon fibre at the dorsal part of the orthosis). All orthoses were expected to prevent plantarflexion and allow dorsiflexion, thus improving first, second, and third rocker. The orthoses were compared through objective gait analysis, including 3D kinematics and kinetics. All orthoses successfully improved the gait pattern and only small differences were noted between the configurations of the different orthoses. The CFO, however, allowed a more physiological third ankle rocker compared with the Orteam/PLS. Although the PLS ensured the highest correction at the ankle around initial contact, the CFO created a significantly higher maximal hip flexion moment in stance. In general, the results of this study indicated a substantial functional flexibility of the CFO.