Purpose:The purpose of the study was to evaluate the effectiveness of respiratory muscle strengthening on trunk control in children with spastic diplegic cerebral palsy .
Subjects and Methods: Thirty children with spastic diplegic cerebral palsy aged from 8to 10 years selected with impaired trunk control and respiratory problems .They have spasticity degree of 1 to 2 according to modified Ashwarth scale. classified into 2 equal groups: control and study. Evaluation w by trunk control measurement scale and spirometer test pre and post treatment.Both groups will receive conventional program designed for diplegic cerebral palsy children in addition to incentive spirometer for study group and breathing exercises for control group for 1hour, three times per week for 1 month .