Total hip reconstruction in the anatomically distorted hip. Cemented versus hybrid total hip arthroplasty

Recent reports in the literature strongly support the idea that cement is the optimum form of fixation of the femoral component in total hip replacement. For hybrid total hip arthroplasty, we used a cemented cup instead of an uncemented cup since this was inevitable in cases of poorly developed acetabulum. The uncemented cone femoral component is also beneficial in cases of extremely narrow and cylindrical configuration of the medullary cavity of untreated congenital dislocation of the hips (CDH) and tuberculosis or septic arthritis in childhood. We reviewed the clinical result of a consecutive series of patients with cemented total hip arthroplasty (THA) compared with recent studies on hybrid reconstruction using survivorship analysis. This subsequent study involved a hybrid uncemented Wagner cone femoral component and a cemented acetabular component with roof reinforcement by additional impacted cancellous allograft with hydroxyapatite (HA). We believe that early failure of the cemented components was due to an adverse effect of thin cement mantles around cemented femoral stems as well as the cemented cup in THA. In addition, 8 patients who received our modification of the Charnley CDH component had poor results even though we reduced the stem geometry and thickness. Furthermore, intraoperative fracture and splitting of the proximal femur was a major complication during implantation. Contrary to expectations, the results of these hybrid reconstructions were extremely encouraging (average follow-up period of 2-4.5 years). In addition to our experience of the cemented versus hybrid THA involving the uncemented Wagner femoral component, we have determined positive indications for the untreated and severely distorted anatomy of bilateral CDH for which surgical interventions for reconstruction were not recommended before.