Spinal fusion cages must withstand complex physiological loading while maintaining vertebral height and promoting successful fusion. This study aims to evaluate and optimize the mechanical performance of five iteratively developed spinal fusion cage designs polyetheretherketone (PEEK) fabricated via additive manufacturing. To identify the design with the best structural behavior and load-bearing capability, experimental axial compression and cyclic loading tests were conducted according to ASTM F2077-18 standards and compared with finite element analysis (FEA) simulations. The study assessed stiffness, displacement response, stress distribution, and overall structural integrity to validate the effectiveness of the design modifications. Results: demonstrated progressive improvements across design iterations, with Optimized Load-Bearing Cage exhibiting the greatest load-bearing capacity, reduced deformation, and more favorable stress distribution relative to earlier prototypes. Comparisons between experimental and numerical results showed general agreement in displacement trends, validating the simulation framework, although discrepancies emerged at higher loads, likely due to simplifications in material modeling and manufacturing-related defects. The Optimized Load-Bearing Cage (OLC) required approximately 3.7-fold higher load to reach equivalent displacement compared to DLC and 2.5-fold higher than SSC. Yield strength of OLC was significantly higher than all other designs (p < 0.001), with mean differences ranging from 40.9 to 50.1. The contact area increased from 8.16 mm(2) to 10.12 mm(2) (similar to 24% increase), contributing to improved load distribution. Stiffness rankings from both experimental and FEA analyses consistently followed the trend: OLC > RDC > SSC > HPC > DLC, confirming improved structural rigidity with iterative design optimization. Cyclic loading tests further showed that OLC exhibited minimal cumulative deformation and only three failure cycles at 400 N and 10 mm s(-1) , outperforming the earlier designs in fatigue resistance. The findings support the role of iterative design optimization combined with FEA and standardized experimental validation in improving spinal fusion implant performance. Future work should expand the mechanical testing matrix, include multi-axis loading and fatigue simulations, and refine manufacturing parameters to enhance reproducibility and long-term implant stability.

Bone infections remain diagnostically challenging because current standard methods rely on microbiological and histopathological testing, which are time-consuming and may delay treatment decisions. This study evaluated handheld near-infrared spectroscopy for detecting spectral changes associated with staphylococcal inoculation in ex vivo human bone. An ex vivo bacterial inoculation model was established using human trabecular bone specimens inoculated with Staphylococcus aureus and Staphylococcus epidermidis. Spectra were acquired using a handheld NIR spectroscopy platform and analysed after standard normal variate preprocessing combined with either smoothing or first-derivative transformation. In total, 120 averaged spectra derived from 40 donors were included. Principal component analysis revealed partial clustering by inoculation status, particularly after derivative preprocessing, but substantial overlap remained. Linear discriminant analysis indicated stronger discrimination between inoculated and uninoculated bone than between the two staphylococcal species. However, classification performance depended on preprocessing and validation strategy; therefore, donor-wise dataset partitioning was used to reduce the risk of overly optimistic performance estimates caused by donor-level information leakage. These findings suggest that handheld NIR spectroscopy may provide rapid, non-destructive information on inoculation-associated spectral alterations in controlled ex vivo bone models. Further studies with sham-incubated controls, repeated donor-level cross-validation, independent external validation, additional pathogens, and clinically realistic confounders are required before clinical translation.

Robotic-assisted total knee arthroplasty (TKA) improves surgical precision and reproducibility. Leg positioners are used to stabilize the limb and support workflow, but their impact in robotic-assisted TKA remains unclear. This study examined whether leg positioner use influences surgical efficiency, workflow, and team experience. A retrospective non randomized single-center analysis was conducted on 79 robotic-assisted TKAs performed between 2018 and 2023 with the MAKO system. Fifty-seven procedures (72%) used a leg positioner, while 22 (28%) served as a control group. Three senior surgeons performed the operations, with step durations and system interactions recorded by independent observers. Surgical phases were divided into preparation, cut-to-suture, and wrap-up, and further into robotic-assisted and conventional steps. Postoperative questionnaires based on the NASA-TLX framework were completed by surgeons and scrub technicians. Median cut-to-suture time was 1:29 h, with no significant difference between leg positioner (1:25 h) and control cases (1:35 h, p = 0.251). Robotic-assisted steps (0:28 h) were unaffected (p = 0.763), while conventional steps were significantly longer without the leg positioner (0:41 h vs. 0:34 h, p = 0.006). Sub-analysis showed slower bone registration and robot positioning with the leg positioner, but faster final implantation (3 vs. 5 min, p < 0.001) and suturing (16 vs. 19 min, p = 0.027). Questionnaires indicated high satisfaction overall, though surgeons reported reduced ease of robotic arm operation and confidence in ligament balancing. The leg positioner redistributed time across surgical steps rather than improving overall efficiency. It offers stability benefits but may restrict intraoperative flexibility. Further studies should address ergonomics, cost-effectiveness, and long-term outcomes.

Bone grafting is widely used in reconstructive surgery, with allogeneic grafts serving as an important alternative to autologous bone. The influence of compaction on the microarchitecture of cleaned cancellous bone allografts remains insufficiently understood. This study investigated the effects of different compaction levels on cleaned cancellous bone chips using micro-computed tomography (micro-CT), with particular focus on structural parameters relevant to graft architecture. Cancellous bone from 15 femoral heads was processed into bone chips, chemically cleaned, and compacted to three density levels (low: 0.15 g/cm3, medium: 0.26 g/cm3, high: 0.41 g/cm3). A structural allograft served as a reference. Microarchitectural parameters, including bone volume fraction (BV/TV), trabecular number (Tb.N), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp), connectivity density (Conn.D), structure model index (SMI), and degree of anisotropy (DA), were analyzed. Increasing compaction led to a significant increase in BV/TV (7.0% to 13.6%), Tb.N, and Conn.D, along with a marked reduction in Tb.Sp (1.97 mm to 0.85 mm; p < 0.001). At high compaction, BV/TV, Tb.N, and Tb.Sp approached the values of the structural allograft reference. However, Tb.Th decreased slightly, and SMI remained consistently high (approximately 2.4), indicating a predominantly rod-like architecture. Compared with the reference, morselized grafts showed lower anisotropy and connectivity. In conclusion, compaction significantly altered graft microarchitecture, increasing density and connectivity while reducing pore size. At high compaction, selected parameters approached those of the structural allograft reference, although differences in Tb.Th, Conn.D, SMI, and DA remained. Even at high compaction, comparatively large pore sizes were maintained, but the biological implications of this finding cannot be determined from micro-CT data alone. These findings highlight the need to balance structural densification with preservation of microarchitectural features potentially relevant for graft incorporation.

Background/Objectives: The perioperative management of a patient's blood values involves the optimization of anemia management in the pre-, intra-, and postoperative periods to avoid blood transfusions. The purpose of this study was to determine the prevalence of pre- and postoperative anemia in patients undergoing elective knee and hip arthroplasty, and explore the change in hemoglobin levels in transfused and non-transfused patients over the course of their hospital stay. Methods: In this retrospective study, data on anemia-influencing factors were collected and examined using multiple regression analysis (OLS model) to determine if they are associated with the average hemoglobin change in 801 patients who underwent a primary knee or hip arthroplasty. The study group was screened for the prevalence of preoperative anemia, and the incidence of postoperative anemia was examined. Results: A total of 801 patients were retrospectively investigated. The length of stay for the two different procedures was significantly different (p < 0.001). There was a markedly higher transfusion rate in the cases requiring longer-than-usual hospital stays. In total, 37 patients (5%) received perioperative erythrocyte transfusions. Total hip replacement (THR) was associated with significantly more erythrocyte transfusions (8%) in comparison with total knee replacement (TKR) (2%) (p < 0.001). Conclusions: Satisfactory results for the prevalence and incidence of anemia in the context of primary knee or hip arthroplasties were obtained in this study. The collected values indicate the need for better implementation and awareness of the importance of adequate patient blood management.

Bone infections, such as fracture-related and periprosthetic joint infections, present significant diagnostic and therapeutic challenges in orthopaedic surgery. Current diagnosic standards rely primarily on tissue cultures of intraoperatively obtained samples - a time-consuming approach with limited sensitivity and specificity and delayed clinical decision-making. This study investigates the use of hyperspectral imaging (HSI) in the visible and near-infrared (Vis-NIR), and short-wave infrared (SWIR) spectral ranges for the rapid detection of bone infections. Using ex vivo human bone samples, an in vitro biofilm model was established with Staphylococcus aureus and Staphylococcus epidermidis. Spectral data were analyzed using machine learning algorithms, including k-nearest neighbors (kNN), support vector machine (SVM), partial least squares discriminant analysis (PLS-DA), and soft independent modeling of class analogy (SIMCA). Vis-NIR-HSI models outperformed SWIR-based classification, achieving classification accuries of up to 99.58 % for distinguishing inoculated from uninoculated human bone samples, and enabling accurate bacterial species differentiation. These results highlight the diagnostic potential of Vis-NIR-HSI as real-time, label-free intraoperative tool for bone infection detection, bridging the gap between preoperative imaging and delayed microbiological results, and supporting immediate surgical decision making.

Background/Objectives: Recent breakthroughs in three-dimensional (3D) printing and high-resolution imaging have opened up new possibilities in personalized medicine, surgical planning, and forensic reconstruction. This study breaks new ground by evaluating the integration of high-resolution peripheral quantitative computed tomography (HR-pQCT) with multimodal imaging and additive manufacturing to assess a chronic, infected gunshot injury in the knee joint of a red deer. This unique approach serves as a translational model for complex skeletal trauma. Methods: Multimodal imaging—including clinical CT, MRI, and HR-pQCT—was used to characterise the extent of osseous and soft tissue damage. Histopathological and molecular analyses were performed to confirm the infectious agent. HR-pQCT datasets were segmented and processed for 3D printing using PolyJet, stereolithography (SLA), and fused deposition modelling (FDM). Printed models were quantitatively benchmarked through 3D surface deviation analysis. Results: Imaging revealed comminuted fractures, cortical and trabecular degradation, and soft tissue involvement, consistent with chronic osteomyelitis. Sphingomonas sp., a bacterium that forms biofilms, was identified as the pathogen. Among the printing methods, PolyJet and SLA demonstrated the highest anatomical accuracy, whereas FDM exhibited greater geometric deviation. Conclusions: HR-pQCT-guided 3D printing provides a powerful tool for the anatomical visualisation and quantitative assessment of complex bone pathology. This approach not only enhances diagnostic precision but also supports applications in surgical rehearsal and forensic analysis. It illustrates the potential of digital imaging and additive manufacturing to advance orthopaedic and trauma care, inspiring future research and applications in the field.

Periprosthetic joint infections occur in 1–2% of all patients undergoing prosthetic joint surgeries. Although strong efforts have been made to reduce infection rates, conventional therapies like one- or two-stage revisions have failed to lower the infection rates. Cold atmospheric plasma (CAP) has shown promising results in reducing bacterial loads on surfaces. In this study, we aimed to investigate the ability of CAP to reduce the bacterial load on metal surfaces with varying distances and different plasma compositions below a temperature suitable for in vivo applications. Methods: Biofilm was formed with Staphylococcus aureus ATCC 29213 and Staphylococcus epidermidis ATCC 12228 cultures on TMZF discs. Plasma treatments using air plasma and argon plasma were conducted on discs containing the established biofilm while the temperature was measured. During the experiments, the duration and the distance of plasma application varied. Afterwards, colony-forming units were counted. Results: The results of this study showed that air and argon plasma could be considered for applications during surgeries at a 1 cm distance. While air plasma showed the highest efficiency in CFU reduction, the temperature generation due to the presence of oxygen poses a limitation concerning the duration of application. The use of argon as a plasma generator does not show the temperature limitation in correlation to exposure time. The use of air plasma with a distance of 1 cm to the application site and an exposure time of 5 s showed the most effective bacterial reduction while not exceeding tissue-damaging temperatures.

Bone infections caused by Staphylococcus aureus and Staphylococcus epidermidis are serious complications in orthopedic surgery. These infections commonly occur in joint replacements, fracture management, and bone grafting procedures. Rapid and accurate pathogen-specific diagnostic methods are urgently needed to support early clinical decisions. Current culture-based methods are slow and delay effective treatment. This study evaluated the diagnostic value of combining Raman microscopy with high-resolution micro-computed tomography (micro-CT). Human bone samples, either uninfected or inoculated with S. aureus or S. epidermidis, were analyzed. Raman spectroscopy detected distinct spectral changes in inoculated bones, including reduced intensity of phosphate (v1PO4 3-), Amide III, and CH2 deformation bands. A single principal component explained 96%-98% of the variance in these infection-related markers. Specifically, the v1PO4 3- and CH2 deformation bands effectively differentiated between S. aureus and S. epidermidis infections, capturing 99%-100% variance. Micro-CT analysis showed significant structural changes in inoculated bones. Trabecular volume, number, and spacing were particularly affected. Among these, VOX-BV/TV and Mean1 best differentiated between S. aureus and S. epidermidis infections (both p < 0.0001). Support vector machine (SVM) classification repeated stratified k-folg cross-validation accurately detected inoculation status. Combining Raman and micro-CT features yielded moderately improved classification performance in pathogen-specific discrimination. These findings demonstrate that combining molecular (Raman spectroscopy) and structural (micro-CT) methods allows rapid, non-destructive diagnosis of bone infections. This multimodal approach may improve diagnostic precision, supports timely clinical decisions, and ultimately improves patient outcomes in orthopedic and trauma surgery.

Background: The ongoing digital transformation of healthcare has enabled innovative technologies that improve diagnosis, treatment planning, and outcomes. Among these, three-dimensional (3D) printing has gained prominence in surgical disciplines for converting digital imaging data into patient-specific physical models. In orthopedics and traumatology, 3D printing is used to produce anatomical models, surgical guides, and custom implants, thereby enhancing preoperative planning, surgical precision, and interdisciplinary communication. Despite its growing adoption, integrating 3D printing into clinical workflows remains complex and requires stringent quality assurance. Each phase of the production process—from image acquisition and segmentation to material selection and post-processing—affects the safety and performance of the final product. Standardized quality approaches and regulatory frameworks are therefore essential to ensure reproducibility, biocompatibility, and patient safety. This systematic review consolidates current knowledge on quality standards and implementation strategies for 3D printing in orthopedic and traumatological care. It identifies practical pathways for clinical integration while highlighting challenges, opportunities, and areas for future research. Methods: A systematic literature search was conducted in PubMed, the Cochrane Library, and the Web of Science, following the PRISMA-P (Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols) 2015 checklist and supplemented by manual searches. Reference management was performed using Rayyan QCRI (Qatar Computing Research Institute). Abstracts and full texts were analyzed with Voyant Tools to identify thematic focuses based on collocate analysis. Results: Nineteen publications met the inclusion criteria. The review highlights a focused but limited body of literature. Key factors influencing product quality include material choice, manufacturing accuracy, and adherence to validated quality control protocols. Discussion: With increasing digitalization and the integration of artificial intelligence, future quality initiatives will likely emphasize standardized preoperative planning, ethical oversight, and regulatory compliance to support personalized care models in orthopedics and traumatology.

Bone disorders such as osteoporosis, osteopenia, and osteoarthritis affect millions worldwide, creating an urgent need for earlier and more accurate assessment of bone health. High-resolution imaging has transformed this field: micro-computed tomography remains the research gold standard for ex vivo and preclinical studies, while high-resolution peripheral quantitative computed tomography enables in vivo clinical assessment of trabecular and cortical bone microarchitecture. Combined with finite element analysis and machine learning, these modalities enable biomechanical modelling, predictive risk stratification, and progress toward personalised treatment. Remaining challenges include cost, limited availability, motion artefacts, and lack of standardisation. This review summarises current advances in imaging and computational methods, highlights their respective strengths and limitations, and outlines future directions required to translate these technologies into routine clinical practice.

Robotic assistance in total knee arthroplasty (TKA) improves surgical precision but may alter intraoperative stress and workload among staff. This study evaluated these effects in 60 robot-assisted procedures involving surgeons, scrub technicians, circulators, and technicians. Preoperative stress was assessed using the STAI-6, intraoperative stress via heart rate, and postoperative workload, satisfaction, confidence, and team interaction through questionnaires. Preoperatively, most staff reported no anxiety, though newly introduced members showed severe anxiety in up to 15% of cases. Intraoperatively, stress patterns varied by role: surgeons peaked during implantation, scrub technicians and circulators during non-robotic phases, and technicians during robotic-specific steps, especially ligament balancing. The robotic arm did not increase surgeon stress but redistributed workload, reducing physical demands for scrub staff and circulators while raising responsibility for technicians. Postoperatively, satisfaction and confidence were high across groups, though scrub technicians reported the greatest workload from added robotic tasks. Robotic systems guided by dedicated professional personnel have the potential to reduce the intraoperative stress level of the whole surgical team, although it adds multiple additional steps to the traditional workflow.

OBJECTIVE OF THE SURGERY:Proximal femur resection with EPR aims to achieve oncological tumor removal while preserving surrounding soft tissue and neurovascular structures, ensuring functional restoration of hip joint stability. INDICATIONS:Malignant bone tumors of the proximal femur, pathological fractures due to tumor involvement, recurrent tumors after previous resection, extensive destruction of the proximal femur due to metastases. CONTRAINDICATIONS:Extensive soft tissue infiltration with inadequate reconstruction potential, generalized metastases without curative treatment options, severe infections in the surgical area, critical general condition prohibiting major surgery. SURGICAL TECHNIQUE:A longitudinal skin incision is made, incorporating the biopsy scar. After sequential soft tissue preparation and preservation of neurovascular structures, femoral osteotomy is performed according to preoperative planning. The hip capsule is preserved and reconstructed. The tumor resection is followed by endoprosthetic reconstruction with a modular tumor prosthesis and subsequent soft tissue reconstruction to ensure optimal stability. FOLLOW-UP:Postoperative management includes early functional mobilization with partial weight-bearing. Adjuvant therapy is planned individually based on tumor staging. Regular radiological follow-up is essential for long-term success. EVIDENCE:EPR following tumor resection is an established procedure with good functional outcomes and oncological safety. Long-term studies demonstrate satisfactory functional results and acceptable complication rates.

Patient positioning in orthopedic and trauma surgery requires maximum stability while preserving passive mobility of the operated limb. When traction tables or positioning aids are used, the legs are secured in traction boots. This study evaluated sub-bandage pressure in the lower extremity of a supine-positioned specimen during hip arthroplasty, comparing single- and double-layer bandage systems. A flexible multilayer and a more rigid single-layer bandage system were compared in mechanical traction tests on a cadaveric specimen. Subbandage pressure was recorded through repetitive measurements at various traction forces, ranging from 80 to 200 N. Due to its rigidity, iFix generated higher pressure near the ankle, providing better stability even at 200 N. In contrast, CO showed higher pressure at the proximal tibia and heel lift at maximum force due to its elasticity. The study found that patient fixation using the tested systems is only justifiable if the tensile force remains below 80 N throughout surgery. Fixation with the tested systems is only advisable if the tensile force remains below 80 N throughout surgery. Short-term increases (e.g., for hip dislocation) are acceptable but should be brief and followed by adequate relief to allow tissue reperfusion. Additional padding is strongly recommended to distribute subbandage pressure at high traction forces.

The prediction of survival rate probability for hip implants, based on clinical data acquired before and after surgery, incorporating patient-specific parameters, represents a pivotal advancement in enabling more precise risk assessment for potential complications, such as aseptic loosening and implant wear-related inflammation, on an individualized basis. This critical step marks a substantial progression toward the realization of digitized and personalized medicine. The objective of this study was to establish prediction aiding correlations between implant wear and migration data, derived from X-ray imaging of 149 patients diagnosed with hip arthritis, and the performance of hip implants. The patients underwent cementless hip replacement surgery, receiving implants consisting of ultra-high-molecular-weight polyethylene (UHMWPE) paired with titanium-aluminum-vanadium (Ti6Al4V) wedges. Over the course of a median follow-up period of 4 years, X-ray assessments were conducted to monitor the migration of the femoral head and acetabular components using Ein Bild Röntgen Analyse (EBRA). Clinical findings revealed a linear relationship between average migration and wear. Notably, it was observed that increased cup migration corresponded proportionally to greater wear values. Furthermore, in-depth analysis revealed significant distinctions based on gender and age. Specifically, the established relationship can confidently serve as a reliable predictive model for the behavior of hip implants in female subjects and individuals aged 50–60 years.

Die proximale Femurresektion mit EPR bedeutet die chirurgischen Tumorentfernung mit dem Ziel der R0-Resektion bei malignen Knochentumoren, nach Möglichkeit (in Abhängigkeit vom Tumor) unter Schonung der umgebenden Weichteil- und neurovaskulären Strukturen sowie der funktionellen Wiederherstellung der Hüftgelenksstabilität. Maligner Knochentumor (Sarkom) des proximalen Femurs, pathologische Fraktur (Metastase/Knochenstoffwechselstörung), Rezidivtumor, (Karzinom‑)Metastase im proximalen Femur. Ausgedehnte Weichteilinfiltration mit unzureichender Rekonstruktionsmöglichkeit (Weichteildeckung), generalisierte Metastasierung ohne kurative Behandlungsoption (Lebensdauer begrenzt), Infektion im Operationsgebiet, kritischer Allgemeinzustand des Patienten, der eine große Operation nicht erlaubt. Der Hautschnitt erfolgt longitudinal unter Einbezug der Biopsienarbe. An dieser Stelle soll erneut auf die Wichtigkeit korrekter Biopsien hingewiesen werden, da sie den Operationszugang vorgeben. Schon die Biopsie sollte im ausgewiesenen Zentrum durchgeführt werden. Nach schrittweiser Weichteilpräparation und Schonung der neurovaskulären Strukturen erfolgt die Osteotomie des Femurs. Die Hüftkapsel sollte nach Möglichkeit erhalten und rekonstruiert werden. Anschließend wird das Tumorresektat entnommen, die prothetische Versorgung mit einer modularen Tumorprothese durchgeführt und die Weichteile rekonstruiert, um eine optimale Stabilität zu gewährleisten. Postoperativ erfolgt eine frühfunktionelle Mobilisation mit Teilbelastung. Eine adjuvante Therapie wird individuell nach Tumorstadium geplant. Regelmäßige radiologische Kontrollen sichern den langfristigen Erfolg. Die EPR nach Tumorresektion ist ein etabliertes Verfahren mit guter funktioneller Wiederherstellung und onkologischer Sicherheit. Langzeitstudien zeigen zufriedenstellende funktionelle Ergebnisse und vertretbare Komplikationsraten.

Background: Aseptic loosening is one of the leading causes of stem revision. Einzel Bild Röntgen Analyse–Femoral Component Analysis allows for the detection of distal stem migration, which is used as a predictive factor for implant longevity. This study aims to demonstrate the migration behavior of a cemented collared anatomical stem. Methods: This study retrospectively examined all patients who received a cemented Lubinus SP II stem (Waldemar Link, Hamburg, Germany) between 2003 and 2019. We used the EBRA-FCA software (University of Innsbruck, Austria) to determine the migration patterns and thoroughly examined the patients’ medical histories. In addition, the potential influence of femoral configuration and BMI on the migration behavior was assessed. Results: This study included 61 patients (48 females and 13 males) with a total of 61 stems that met our inclusion criteria. The mean age at surgery was 76 years (ranging from 30 to 93 years). According to EBRA-FCA migration analysis, a median subsidence of 0.7 mm was observed at 24 months and at the final follow-up (median 78 months). Distal stem migration was significantly higher at the 6-month time point in patients with Dorr type A femurs compared to Dorr type B femurs (p = 0.016). Body mass index (BMI) had no significant effect on stem migration. Conclusions: The measured subsidence of the Lubinus SP 2 stem using EBRA-FCA was below established thresholds, indicating excellent long-term outcomes. Although there was significantly increased subsidence in Dorr type A femurs during the initial 6 months, thereafter, no statistically significant difference was observed compared to Dorr type B femurs.

Cementoplasty has been successfully used for treating fractures in various parts of the human body, although the use in weight-bearing long bones is a subject of controversial debate. Strategies to improve the mechanical properties of polymethylmethacrylate-based bone cement (BC) comprise changing the chemical composition or the application of metal reinforcement strategies. In clinical practice reinforced bone cement is used despite biomechanical basic research regarding this topic being scare. The aim of the present study was to evaluate the biomechanical properties of two different reinforcement strategies against non-reinforced polymethylmethacrylate-based BC subjected to bending stress. In this controlled comparative laboratory analysis, we evaluated two types of reinforcement strategies in comparison to a control group (C). BC was reinforced with a Kirschner wire (group CW) or with a prestressed twinned steel cable (group CC); control group C was native polymethylmethacrylate-based BC. All the samples were prepared using a custom-made mould and underwent 4-point bending stress until fracture using a testing machine. Flexural strength, maximum strain, and Young’s modulus were assessed for the three groups and compared using the Kruskal‒Wallis test. The mean flexural strength in MPa was 48 ± 12 in C, 64 ± 6 in CW, and 63 ± 14 in CC. A significantly greater flexural strength of + 33

Background/Objectives: This study evaluated the learning curve for robotic-assisted total knee arthroplasty (RA TKA) performed by three experienced surgeons, focusing on procedure duration, surgeon satisfaction, and confidence. Methods: A prospective study was conducted with three senior arthroplasty surgeons, each performing 15 RA TKA procedures using the Triathlon Knee System with the Robotic Arm Interactive Orthopedic (RIO) System. Data on preparation, cut-to-suture, and breakdown times were collected. Surgeon anxiety levels were measured preoperatively using the STAI-6 scale, while postoperative satisfaction and confidence were assessed via a questionnaire. Statistical analysis was conducted using GraphPad Prism. Results: Of 50 scheduled surgeries, 45 were completed. The average cut-to-suture time was 1 h 38 min, with significant time reductions in robotic-specific steps as experience increased. Comparing the first five surgeries to the last five, the time for navigation hardware mounting, landmarks registration, femur and tibia registration, and bone preparation decreased by up to 30% (p < 0.001 to p = 0.025). General instrument preparation time decreased by 20% (p = 0.004). Surgeon anxiety levels dropped, indicating increased comfort with the system, while postoperative surveys showed increased satisfaction and confidence. Conclusions: The study demonstrated a substantial learning curve for RA TKA, with improved efficiency and surgeon confidence by the fifteenth procedure. These findings highlight the potential for streamlined workflows and guide training for new adopters of robotic knee arthroplasty.

The increasing numbers of total joint replacements and related implant-associated infections demand solutions, which can provide a high-dose local delivery of antibiotics. Antibiotic-loaded bone cement (ALBC) is an accepted treatment method for infected joint arthroplasties. The mechanical properties of low-dose gentamicin-loaded bone cement (BC) in medium- and high-viscosity versions were compared to unloaded BC using a vacuum mixing system. As an additional control group, manual mixed unloaded BC was used. In a uniaxial compression test, ultimate compressive strength, compressive yield strength, and compression modulus of elasticity, as well as ultimate and yield strain, were determined according to ISO 5833-2022 guidelines. All groups exceeded the minimum compressive strength (70 MPa) specified in the ISO 5833 guidelines. Both ALBC groups showed a similar ultimate compressive and yield strength to the unloaded BC. The results showed that vacuum mixing increased the compression strength of BC. ALBC showed similar compressive strength to their non-antibiotic counterparts when vacuum mixing was performed. Added low-dose gentamicin acted as a plasticizer on bone cement. From a biomechanical point of view, the usage of gentamicin-based ALBC formulations is viable.