Placebo_comparator: Group A

Physical therapy program The exercise session for one hour for each child , conducted 3times/ week for 3 successive months.~1. Flexibility exercises for shorted muscles and spastic muscles.~2. Strengthening training focusing on the trunk lower limb and upper limb muscles for weak muscles.~3. Postural control exercise in different positions and different surfaces~4. General endurance training~5. Exercises to facilitate hand function~6. Exercises included, grasping a cube, transferring cube, removing and placing pegs, releasing cube and placing cubes. Strengthening exercises of the intrinsic muscles of the hand

Experimental: Group B

The exercise session for one hour for each child same as group A, conducted 3times/ week for 3 successive months plus the combined biofeedback therapy and FES at anti spastic muscles (shoulders flexors, elbow and wrist extensors