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Background and Aim: in hemiplegic children Postural tone of the two sides of body is different. Once, asymmetric stance is a typical state in individuals' with unilateral pain and/or paresis and standing is with weight bearing on the stronger side. Obviously, an asymmetric stance with majority of weight bearing on the affected side can counter faces individual with the falling risk and causes instability. It seems coordinating of the two sides of body is the most vitally important therapeutic exercises in hemiplegic patients. Although stable stance is a simple postural task but it's controlled semi-automatically by cortical and spinal centers. It is established that stable standing, also demands cognition resources. So, postural control demands the interaction between musculoskeletal and nervous systems.
Material and method: In this clinical trial (before-after) 17 children 5-12 years old with spastic hemiplegia were participated. The subjects stayed in the center of force plate with the most stable standing position while using /not-using lateral wedge and in each state with/without doing cognition task. Short- memory test of digit span used as dual task condition. The mean range of fore-after and mediolateral sway and velocity and area as postural control independent variables and error measures in recalling of randomized digit chain as cognition task independent variables were registered.
Results: The wedge affected Rsw (P=0.015), Area (P=0.007) and Vm (P=0.005) significantly. Dual task also had significant effect on Rfa (P=0.014), Rsw (P=0.014), Area (P=0.002) and Vm (P=0.002). But the wedge declines its effect properly.
Conclusion: The results represent that a 5º lateral wedge applied to the unaffected limb, can improve factors of postural control even in Dual tasking thus The wedge can be used with a good effect on the posture of hemiplegic children.