Abdullah K, et al. - This study was implemented to describe an 11-year mean follow up of the effectiveness of bone impaction grafting with bone and Hydroxyapatite (HA) for large, uncontained acetabular defects in primary and revision hip surgery. Findings revealed that 11-year survivorship, the longest survivorship of bone impaction grafting with morcellised bone and HA substitute, was excellent and so were function and pain, but radiological findings of lysis and migration in 8 and 4 cases, respectively, may be of concern for the immediate future and will need close monitoring. Data suggested that due to restoration of bone stock, revision may be easier even in these cases.