Periprosthetic joint infection (PJI) is a complex complication of total joint arthroplasty, with microbiological profiles varying across centers worldwide. However, most studies are limited to single-center or intra-country multicenter analyses, often including mixed cohorts of primary and revision PJI cases, with limited data regarding global antibiotic resistance patterns. This study compared the microbiological characteristics, polymicrobial culture rates, prevalence of culture-negative infections, and antibiotic resistance patterns in PJI cases across five referral centers from five continents. A total of 717 patients with primary hip and knee PJI were included from centers in Argentina, Canada, Turkey, England, and New Zealand. Staphylococcus aureus and Staphylococcus epidermidis were the most common pathogens (48.5%, p < 0.01). Culture-negative infection rates varied significantly, ranging from 4.2% (England) to 24.6% (Turkey) (p < 0.01). Polymicrobial infections were the most frequent in Canada (8.9%) and the least frequent in England (1.1%) (p < 0.01). Gram-negative bacteria comprised 13.1% of culture-positive cases, with no significant intercountry difference. Multidrug resistance was observed in all centers, ranging from 23.7% (Argentina) to 43.1% (Turkey), with no statistical significance. Vancomycin resistance was detected in England (2.3%) and Canada (1.2%) but absent in Turkey, New Zealand, and Argentina. These findings underscore significant intercontinental variability, emphasizing the need for regional considerations in regards to empiric antibiotic selection and PJI management.

Medial opening wedge high tibial osteotomy aims to correct coronal plane deformities and redistribute the load in varus-aligned knees. However, changes in the sagittal plane during medial opening wedge high tibial osteotomy can influence the posterior tibial slope, potentially affecting knee biomechanics. The sagittal inclination angle of the osteotomy, which is the angle between the medial joint line and the osteotomy line on lateral view, is a relatively new parameter that has been discussed in the literature, as a factor influencing the posterior tibial slope. The aim of this study is to investigate success rates in achieving the targeted postoperative slope, which is to avoid increasing the slope, with posteriorly inclined sagittal osteotomy. This research was designed as a retrospective single-center case-series study. In order to avoid increasing the posterior tibial slope, our modified surgical technique involves adjusting the sagittal inclination angle to be 10o posteriorly inclined. This angle was considered to be posteriorly inclined if the anterior portion of the osteotomy was inclined proximally. Pre- and postoperative posterior tibial slope measurements were recorded. Changes in postoperative tibial slope compared to preoperative tibial slope were statistically evaluated using the paired t-test. Changes were categorized as decreases, no change, or increases, and these three groups were compared using the one-sample binomial test. Ninety-five patients (77 women and 18 men) with a mean age of 52.8 ± 7.0 were included in this study. The preoperative mean posterior tibial slope was measured as 12.5 ± 3.9° and the postoperative mean PTS was 10.6 ± 4.3°. A paired t-test revealed a statistically significant difference of 1.9 ± 3.8° (95% confidence interval: 1.13–2.71; p < .01). In four cases (4.2%), the PTS remained the same, while for 67 patients (70.5%) the PTS decreased and for 24 patients (25.3%) the posterior tibial slope increased. Therefore, a decrease or no change in the posterior tibial slope was achieved in 74.7% of all cases (p < .01). Modifying the sagittal inclination angle to achieve a posteriorly inclined osteotomy during medial opening wedge high tibial osteotomy may prevent increasing the posterior tibial slope in the majority of cases.