['Neurogenic hip dislocation is frequently observed in patients with cerebral palsy (CP). If the hip is not centred but not dislocated, the hip joint can be recentered with minor operative effort. Reconstructive procedures are indicated if the femoral head is subluxated or dislocated. There are no data as to when destruction of the femoral head requires a salvage procedure or whether hip reconstruction surgery is successful in restoring joint congruity in patients with CP. Our aim was to investigate femoral head plasticity after hip reconstruction surgery in a long-term outcome study.', 'We studied a large cohort of patients with CP and high hip dislocation (Tönnis grade IV) before surgery. Sixty-eight patients were assessed, of whom 23 presented with bilateral high hip dislocation, and 91 complex hip reconstructions were conducted. Standardised radiographic examination was performed before and directly after surgery and at the long-term follow-up examination.', 'Pain was the most frequent reason for complex hip-joint reconstruction (49 patients, 72%). An impressive improvement in pain was demonstrated postoperatively. Forty-five hip joints presented aspheric incongruity postoperatively, which improved on average 7.7 years after surgery and 59 hip joints showed congruency. Only 15% of patients experienced pain at the time of final follow-up, and that was of low intensity.'] Is hip reconstruction surgery successful in restoring joint congruity in patients with cerebral palsy : long-term outcome?