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Background: Ceramic-on-ceramic (COC) bearings in total hip arthroplasty (THA) have long been considered the coupling with the lowest overall wear. However, concerns about complications such as ceramic breakage and noise, combined with the improved performance of polyethylene, have limited its use in the United States. This postapproval follow-up reports long-term (10 years) results of Delta COC in THA patients primarily enrolled in an Investigational Device Exemption study. Methods: Patients received Delta COC THA in a prospective multicenter study with either 28-mm (N = 105 hips in 104 patients) or 36-mm (N = 81) articulations. Annual clinical and radiographic evaluations were performed for years 5 to 10, and study patients were asked about hip noises and reproducibility. Results: There have been 4 additional reports of noise in 4 patients (COC 28, n = 3; COC 36, n = 1). The cumulative incidence rate for squeaking or noise at 10 years is 5.9% for COC 28 and 13.5% for COC 36. There have been 2 additional reports of dislocation in 2 patients (COC 28, n = 1; COC 36, n = 1). The cumulative incidence rate for dislocation at 10 years is 3.7% for COC 28 and 3.5% for COC 36. At 10 years, there were greater than 40 hips available for follow-up. At mean 10-year follow-up, there were a total of 3 ceramic liner fractures, but none since the previous report. There were no revisions in the 28-mm cohort, and 2 revisions in the 36-mm cohort (1 for recurrent dislocation and 1 for pain and noise). Overall Kaplan-Meier survivorship was 95.96% at 10.5 years (28 mm: 97.68% at 10.2 years; 36 mm: 94.11% at 10.4 years.) Conclusions: At 10-year follow-up, we report excellent results in regard to survivorship, with one patient revised for pain with associated squeaking.

Purpose: Although total knee arthroplasty is one of the most successful and consolidated surgical procedure, the infection rate is still elevate. To treat infected knee arthroplasties, in the past years was approached a procedure that involved the implantation of an antibiotic-loaded temporary spacer. This spacer helps maintain an appropriate soft tissue envelope and the patients are able to walk during the interim period. This study investigated the tribological behavior of antibiotic-impregnated knee spacers under dynamic loading., Methods: Three temporary spacer specimens were subjected to a cyclic test on a knee wear simulator for 500,000 walking cycles under a modified international guidelines (ISO 14243). During this test we address about the evaluation of the mechanical resistance and to quantify the wear rate of the devices. All the kinematics and the axial load were set to simulate more than six months of patient use., Results: All the femoral and tibial specimens completed the 500,000 cycles without breakage. The wear patterns observed on the contact surfaces were similar over the specimens., Conclusions: On the basis of the present data, the authors believe that the use of temporary antibiotic-impregnated knee spacers could be an effective wear-resistance temporary substitute of a total knee two-stage revision arthroplasty., (Copyright © 2019 Elsevier Ltd. All rights reserved.)