Total Hip Arthroplasty Using Hybrid Ceramic Bearing: A Minimum 10-Year Followup Study

Background: Contemporary ceramic articulation in total hip arthroplasty (THA) has shown successful clinical and radiologic outcomes at mid-to-long term. Delta ceramic, which includes 24% zirconia, has been developed to reduce the rate of ceramic fracture. However, the phase transformation of the zirconia that might cause surface roughness, ceramic wear, and subsequent osteolysis remains a concern. The purpose of this study was to evaluate clinicoradiological outcomes, ceramic-related complications, and survivorship of THA with the use of hybrid ceramic bearing; BIOLOX delta liner-on-BIOLOX forte head articulation at a minimum followup of 10 years. Materials and Methods: One hundred cementless THAs (85 patients) were performed with the use of 36-mm hybrid ceramic bearing. The thickness of the delta ceramic liner was 4-6 mm. Four patients (4 hips) were lost and six patients (6 hips) died within 10 years after the operation. Thus, the remaining 75 patients (90 hips) were followed up for 10-12 years. There were 43 men and 32 women. The mean age of these patients at the index operation was 58 years (21-78 years). Results: There were no fractures of ceramic liner or head. There was no measurable ceramic wear, and neither pelvic nor femoral osteolysis was identified. All acetabular and femoral components were bone-ingrown. Three (3/90, 3.3%) patients noted noise of clicking sound. The mean Harris hip score was 87 points (range 72-99 points) at the time of final followup. THA survivorship with revision surgery as an endpoint was 97.8% (95% confidence interval: 91.4%-99.8%). Conclusions: The long term result of cementless THA with the use of a large BIOLOX forte head on the BIOLOX delta liner showed an encouraging result. Wear or osteolysis associated with composite of 24% zirconia in the fourth-generation ceramic was not observed at a minimum followup of 10 years.