Surgeons' Awareness and Impaction Technique of a Ceramic Liner into a Metal Shell.

Background: In ceramic-on-ceramic total hip arthroplasty, firm locking is necessary between a ceramic liner and an acetabular metal shell to prevent dissociation of the liner from the metal shell. We evaluated surgeons' awareness of the technique for inserting the ceramic liner and measured the impaction force applied by surgeons during the insertion of the ceramic liner. Methods: To evaluate the awareness, we conducted a survey using a questionnaire including techniques for ceramic liner insertion. The impaction force was measured using an impaction simulator in 224 surgeons. Results: Most surgeons answered that they cleaned and dried up the inner surface of the metal shell before inserting a ceramic liner (96.4% and 86.2%, respectively), and 74.6% checked the correct seating of the ceramic liner. However, only 23.2% correctly answered that a minimum of 2kN (a light strike) was necessary to obtain a sufficient fit between the metal shell and the ceramic liner. The impaction force was weaker than 2 kN in 9.4% of the surgeons. Conclusions: Education about the adequate impaction force to obtain a firm fit of the ceramic liner is necessary for surgeons who perform total hip arthroplasty using ceramic-on-ceramic bearings.