Search Results (2)

Background/Objectives: Aseptic loosening is the leading cause of late revision in total hip arthroplasty, primarily due to degenerative oxidation of polyethylene components, leading to wear particle formation and periacetabular osteolysis. This study aimed to analyze the oxidation levels in polyethylene liners and cemented cups retrieved from revision surgeries using Fourier-transform infrared spectroscopy (FTIR) and to explore the correlation between oxidation levels and factors such as head size, head material, fixation method, and implant survival time. Methods: Polyethylene liners and cups were analyzed post-revision surgery to assess oxidation levels, which were then compared to periacetabular bone loss measured by the Paprosky classification. This study evaluated the impact of head size (28 mm vs. 32 mm), head material (ceramic vs. metal), and fixation methods on oxidation. The relationship between the mean oxidation index (OI) and implant survival time was also investigated. Results: There was a significant positive correlation between the mean oxidation index of the polyethylene components and the severity of periacetabular osteolysis according to the Paprosky scale. While the mean OI for samples articulating with ceramic heads was lower than for those with metal heads, and the mean OI for samples with a 32 mm head size was lower than for those with a 28 mm size, these differences were not statistically significant. Furthermore, the fixation method did not affect the oxidation index, and no correlation was found between OI and the survival time of the implants. Conclusions: This study confirms a direct correlation between polyethylene oxidation and periacetabular osteolysis in hip replacements, highlighting the importance of material choice and design in potentially reducing the risk of aseptic loosening. Despite the lack of significant differences in oxidation levels based on head material and size, these factors may still play a role in the long-term outcome of hip arthroplasty, warranting further investigation. Full article

Two-stage revision is considered the gold standard treatment for chronic periprosthetic joint infection (PJI). During the interim period, between explantation of the infected hip endoprosthesis and revision arthroplasty, individually formed articulating hip spacers made of polymethylmethacrylate (PMMA) bone cement can be used to provide better soft tissue preservation, local antibiotic release, and improved postoperative mobilization. If effective prevention from luxation is achieved, hip function and hence overall patient satisfaction is improved. Zirconium oxide particles inside conventional PMMA bone cement, however, are known to enhance third-body wear, which may cause alterations of the metal head in the articulating spacer and hence become a serious risk for the patient. Therefore, the aim of our study was to analyze whether the articular surface of cobalt-chrome (CoCr) femoral heads is significantly altered in the setting of a metal-on-cement articulation during the interim period of two-stage revision for PJI. We analyzed a consecutive series of 23 spacer cases and compared them with femoral heads from two series of conventional hip arthroplasty revisions with metal-on-polyethylene articulations and different time intervals in situ. To investigate metallic wear, the femoral heads were thoroughly examined, and their surface roughness was measured and analyzed. We found no significant differences between the two conventional hip arthroplasty groups, despite their very different times in situ. Furthermore, the individually different times in situ within the spacer group had no significant impact on surface roughness, either. Compared with the spacer group, the surface roughness of the metal femoral heads from both conventional hip arthroplasty groups were even higher. Within the spacer group, roughness parameters did not show significant differences regarding the five predefined locations on the metal head. We conclude that metal-on-cement articulations do not cause enhanced surface alterations of the metal femoral head and hence do not limit the application in articulating hip spacers in the setting of two-stage revision for PJI. Full article