Abstract
Background
The bearing surface is one of the important factors that affect the longevity of total hip replacement (THR). The ceramic on ceramic bearing decreases the rate of dislocation event and the amount of wear debris. We encountered cases of incomplete seating of the liner with the TriAD acetabular system.
Patients and Methods
We examined 25 hips in 24 patients who had undergone total hip replacement by using the TriAD shell with a metal-backed alumina liner. We used the Hardinge approach for performing surgery in all patients. Incomplete seating was judged on the basis of plain anteroposterior and/or oblique radiographs obtained immediately and 3 months after the operation.
Result
Six hips (24%) were found to have incomplete seating of the liner. Four cases were confirmed on the basis of plain radiographs obtained in the early postoperative period, and 2 were identified at a follow-up examination conducted more than 3 months postoperatively. All patients showed clinical improvement. Revision surgery was not required to rectify incomplete seating.
Conclusions
We agreed with Langdown AJ. et al who reported that this implant design had an elevated rim and that shell deformity upon implantation can cause incomplete seating. Therefore, when using this implant, due care should be taken during implantation of the liner. It is necessary to conduct follow-up examination in patients with incomplete seating of the liner because these patients can have problems such as metallosis, corrosion, fatigue fracture of implants, and implant loosening.
