Periprosthetic joint infection (PJI) remains one of the most serious complications after total joint arthroplasty. This retrospective 1:1 matched case–control study investigated preoperative predictors and patient phenotypes associated with PJI in 182 patients (91 cases, 91 controls) undergoing hip or knee arthroplasty between 2013 and 2024. Variables with skewed distributions were log-transformed, and multivariable logistic regression with LASSO regularization identified independent risk factors. Unsupervised K-means clustering was applied to perioperative features to explore data-driven patient phenotypes. Preoperative anemia (OR 5.91, p = 0.026), higher ASA score (OR 1.77, p = 0.033), and surgical delay (OR 1.67, p = 0.024) independently predicted infection, while age and CRP showed non-significant trends. The resulting five-variable preoperative model achieved an AUC of 0.718 (optimism-corrected AUC of 0.661) for infection prediction. Clustering analysis revealed three phenotypes: anemia-dominated, elderly but short-procedure, and high surgery duration with significantly different infection rates (χ² = 23.5, p < 0.001) but similar mortality (p = 0.068). This integrative approach combining regression-based prediction and phenotype discovery enables clinically interpretable, preoperatively applicable risk stratification. The findings identify anemia, comorbidity burden, and surgical delay as key modifiable targets for preventive optimization before arthroplasty. External validation and recalibration to population-level incidence are warranted before clinical implementation.

(1) Background: The reconstruction of periacetabular defects after tumor resection remains one of the most challenging procedures in orthopaedic oncology. The modular LUMiC^® system was designed to improve fixation stability and reduce implant-related complications compared with earlier hemipelvic prostheses. We investigated patient and implant survival after LUMiC^® reconstruction, complication types and functional outcomes. (2) Methods: Eighteen patients (8 men, 10 women; mean age 58.9 years) underwent LUMiC^® endoprosthetic reconstruction between 2011 and 2025. Kaplan–Meier analysis was used to estimate patient and implant survival. Complications were categorized according to Henderson. Functional results were evaluated at follow-up using MSTS and TESS. (3) Results: Mean follow-up was 35.52 months (SD 36.89). Overall implant survival was 72.2%. Instability (27.8%) and infection (16.7%) were the leading complications. Two-thirds of patients required at least one revision (mean 3.1 revisions per case). Metastatic disease reduced patient survival (p = 0.012) but did not affect implant longevity (p = 0.31). Functional outcomes were available for only 3 of 18 patients and should therefore be regarded as exploratory. Mean MSTS was 58.9% (SD 21.43) and mean TESS was 73.4% (SD 6.836). (4) Conclusions: Despite high revision rates, the LUMiC^® prosthesis provides durable fixation. Early revision does not appear to compromise implant survival. However, the small and heterogeneous cohort represents a limiting factor of this study.

The specialty background of intensive physicians managing severely injured patients varies internationally, with trauma ICUs often led by either trauma surgeons or anesthesiologists, both of whom receive additional intensive care training. Whether physician specialty affects outcomes remains uncertain. We conducted a retrospective single-center cohort study of patients aged ≥ 16 years with an Injury Severity Score (ISS) ≥ 16 admitted to a level I trauma center between January 2005 and December 2022. Patients were treated either in a trauma surgery ICU (T-ICU) or an anesthesiology ICU (A-ICU). Briefly, 1:1 matching was conducted based on demographic and injury-related variables, with the primary outcome being in-hospital mortality and secondary outcomes including transfusion requirements, duration of mechanical ventilation, ICU and hospital length of stay, and Glasgow Outcome Scale (GOS) at discharge. Among the 1015 eligible patients (T-ICU: n = 920; A-ICU: n = 95), 52 patients (26 per group) were successfully matched with comparable baseline characteristics. No significant differences were observed in mortality, GOS, transfusion requirements, ventilation duration, or ICU/hospital length of stay. These findings suggest that, when both are led by certified intensive care specialists, trauma surgery- and anesthesiology-based ICUs achieve comparable outcomes, supporting multidisciplinary models while highlighting the need for larger multicenter studies.