11-Year Mean Follow-Up of Acetabular Impaction Grafting With a Mixture of Bone Graft and Hydroxyapatite Porous Synthetic Bone Substitute

Abstract

BackgroundWe report 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 surgeries. MethodsOver 5 years, 47 total hip arthroplasties with uncontained acetabular deficiencies were performed by augmentation using an impaction graft with 50:50 mixture of freeze-dried bone allograft and HA. Ten were primary total hip arthroplasties and 37 revision procedures. X-rays were taken postoperatively, 6 weeks, 3 months, and then annually to assess incorporation of the graft, radiolucent lines, resorption, or migration of components. Functional outcomes were assessed by annual pain and function parts of the Harris Hip Score. ResultsAt a mean follow-up of 10 years, the survivorship was 100%. All patients were accounted for; 6 had died. The Harris Hip Score for pain improved from 9 and 17 (primaries and revisions, respectively) to 39 and 41. For function, there was an improvement from 20 and 19 to 32 (both groups). There were lucent lines in 8 cases, 3 cups had minor/stable migration, and one cup had significant migration (>15 mm). Graft incorporation had occurred in 20 hips. ConclusionThis is the longest survivorship of bone impaction grafting with morcellised bone and HA substitute.Although 11-year survivorship, function and pain are excellent, radiological findings of lysis in 8 and migration in 4 cases may be of concern for the immediate future and will need close monitoring. Even in these cases, revision may be easier because of restoration of bone stock.