Retrieval analysis of a polycarbonate-urethane acetabular cup: a case report

An acetabular cup made of a compliant polycarbonate-urethane material has been introduced as an alternative bearing solution. This case study examines the use of this acetabular cup in a single patient at 12 months. The cup had minimal loss of thickness with the most being in the superior area (approximately 10%) and minimal loss of weight (2.4%). On the back side was evidence of abrasive macroscopic wear on one side of the implanted component in the area of directional loading from the head to the acetabulum. On the front side, the wear rate was determined to be minimal (less than 15 mm3 per year), meaning that most of the change in thickness and weight was caused on the back side. The retrieved synovial fluid appeared normal in color and volume at the time of revision. The histology of the tissue taken showed minimal wear particles and minimal reactivity, confirming that the patient did not have any signs of synovitis.The analysis of the cup confirms the preclinically determined low wear articulation and biocompatibility of polycarbonate-urethane as a weight-bearing material. In summary, the surgical findings, data reviewed, and images taken from this case report warrant further study.