The study presents the long-term results of operative treatment of spastic subluxation and dislocation of hip joints in cerebral palsy children with open reduction and pelvic transiliac osteotomy by Dega. The subjects were 25 patients (30 hips) and the follow-up lasted from 3 to 25 years (average 12 years). Final examinations were carried out after the end of body growth. Detailed analysis covered a patient's function, occurrence and intensity of pain in the hip joint, value of radiological parameters such as angle of centre-edge of the roof after Wiberg (CE), acetabular index (AI), neck-shaft angle (NS) and migration percentage (MP). The final evaluation of radiological results was carried out in accordance with Severin's classification. The clinical and radiological results obtained showed gradual deteriorations in comparison with the early postoperative results (dating from 12 months after surgery). In the final examination, in one patient a recurrent dislocation of the hip joint was diagnosed and subluxation was diagnosed in six patients (23%). Only the values of the CE angle went up (from -16 degrees in the early postoperative examination to 20 degrees in the final assessment), which we consider to be due to the change of sphericity of the head of femur. The remaining radiological parameters did not change significantly: AI from 22 degrees to 23 degrees, MP from 11% to 23%, NS from 133 degrees to 140 degrees. The surgical method presented is currently applied in a modified form, with a wider release within the soft tissues, more radical varusderotation osteotomy and greater shortening of the femur.