Background: The present study aimed to evaluate the effect of fossae lumbales laterales and pelvic incidence (PI) on transsacral corridors. Methods: Patients who underwent pelvic computed tomography (CT) during routine therapy in a single center between 2015 and 2020 were retrospectively reviewed. The patients’ age and sex were documented during CT examination. Measurements were performed for both the upper and second sacral segments. Height and weight of the patients were determined using appropriate tools and body mass index (BMI) was calculated. Transsacral corridors were identified in true coronal and true sagittal planes and their width was determined as the maximum gap measured so that no screws could come out of the transacral corridors. PI was measured. Results: Our study included 244 (57%) male and 184 (43%) female patients, who had a mean age of 49.3 ± 14.15 years (range, 18–89 years) and a mean BMI of 26.57 ± 2.38 kg/m 2 . No statistically significant correlation was found between the detection of the dimple sign in physical examination and the presence of an adequate corridor. The PI was statistically significantly higher in the patients with dimples (p < 0.001). PI of the female patients was higher than that of the male patients (p = 0.026). The correlation between PI and the existence of adequate corridors for S1 and S2 screws was not statistically significant (p = 0.858 and p = 0.129, respectively). On the relationship between the presence of adequate S1 and S2 corridors where transsacral screws could be sent, an inverse relationship was detected: if the S1 transsacral corridor was adequate, the S2 corridor was inadequate or vice versa. Conclusions We could not obtain meaningful results on the use of the dimples of Venus or PI instead of CT to evaluate the adequacy of transverse corridors. Nevertheless, we confirmed that an increased PI was associated with the presence of dimples of Venus.

Background: This study aimed to investigate whether periprosthetic joint infection (PJI) can be predicted by the C-reactive protein-to-lymphocyte ratio (CLR), whether this ratio increases the accuracy of PJI diagnosis, and whether it is more sensitive than other blood values and ratios. Methods: The patients were divided into two groups: the septic revision (SR) group and the aseptic revision (AR) group. In cases of septic revision, the diagnosis of PJI was made based on the criteria proposed by the European Bone and Joint Infection Society (EBJIS). The groups were compared in terms of age, sex, body mass index, comorbidity, and preoperative laboratory results. The sensitivity, specificity, and diagnostic performance of the values and ratios were analyzed and compared. Results: The receiver operating characteristic (ROC) analysis for the CLR gave a diagnostic value of 15.52, which provided a sensitivity of 91.1% and a specificity of 64.2% for PJI. The CLR gave lower specificity and higher sensitivity compared to the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) values. The ROC analysis showed that the CLR had a similar area under the curve (AUC) with the ESR and CRP (0.808). The CLR had a higher specificity than other ratios (platelet volume ratio, neutrophil-tolymphocyte ratio, platelet-to-lymphocyte ratio, and monocyte-to-lymphocyte ratio) and a higher value of the AUC. In the multivariate analysis, the CLR (hazard ratio, 1.088; 95% confidence interval, 1.063–1.113; p < 0.001) was found to be a significant risk factor. As CLR increased by one unit, the risk of PJI increased by 1.088 times, and it was statistically significant (p < 0.001). Conclusions The findings of this study suggest that CLR can serve as a valuable screening tool for diagnosing PJI. CLR demonstrated higher sensitivity in predicting PJI compared to ESR and CRP, and it exhibited greater specificity than other infection markers.