Robotic Assistance Research Articles

Robotic assistance improves success of cementless component fixation in one total knee arthroplasty system

IntroductionNew cementless implant designs in total knee arthroplasty (TKA) have begun to shift the longstanding practice of cemented fixation. With aseptic loosening a leading cause for revision of cementless implants, initial osteointegration is critical for component survivorship. Robotic-assisted TKA (RA-TKA) has shown promising results in recent literature at improving component accuracy. The current study aims to evaluate if robotic assistance affects the success of cementless fixation in primary TKA. Methods445 cementless primary TKA components from one manufacturer implanted by five surgeons between June 2018 and October 2022 were retrospectively reviewed. Those with minimum one-year follow-up were analyzed. Femoral and tibial components were reviewed separately and grouped based on whether manual or RA-TKA from the same manufacturer was performed. Fisher’s exact test was used to analyze if aseptic loosening rates were different between the two techniques. Results373 (82%) cementless components from a single knee system were included. 146 femoral and 103 tibial components were implanted using RA-TKA, while 63 femoral and 61 tibial components were implanted manually. At a mean follow-up of 18 months (range, 12 to 51 months), successful fixation was achieved in 96.2% of all components. No femoral components from either group were revised due to aseptic loosening. Four manually implanted vs. no robotically assisted tibial components were revised due to aseptic loosening (6.6% vs 0.0%; P = 0.038). ConclusionThe performance of modern cementless femoral components was excellent with or without robotic assistance, however RA-TKA improved the survivorship of the same system’s cementless tibial component.Level of Evidence: Level III.

Impact of robot assistance on restoration of limb length and offset distance in total hip arthroplasty

To analyze the impact of robot assistance on the restoration of limb length and offset distance in total hip arthroplasty (THA). A retrospective analysis was conducted on the clinical data of 316 patients who underwent unilateral primary THA between September 2019 and August 2023. Among them, 117 patients underwent robot-assisted THA (group A), and 199 patients underwent conventional THA (group B). There was no significant difference between the two groups in the gender, age, or side of the hip replacement ( P>0.05); but there was a significant difference in the preoperative diagnosis ( P<0.05). The leg length discrepancy (LLD) and global offset (GO) dfference were measured on preoperative anteroposterior pelvic X-ray films, and absolute values were used for comparison between groups. The operations in both groups were successfully completed. Postoperative imaging measurements showed that the LLD and GO dfference in group A were significantly lower than those in group B ( P<0.05). Among them, group A had 32 cases (27.4%), 5 cases (4.3%), and 0 case (0) of LLD>3 mm, >5 mm, and >10 mm, respectively, while group B had 115 cases (57.8%), 75 cases (37.7%), and 22 cases (11.1%), respectively; and the differences in above indicators between groups were significant ( P<0.05). Group A had 40 cases (34.2%), 3 cases (2.6%), and 0 case (0) of GO dfference>5 mm, >10 mm, and >20 mm, respectively; group B had 103 cases (51.8%), 54 cases (27.1%), and 7 cases (3.5%), respectively. There was no significant difference in the proportion of patients with GO>20 mm between groups ( P>0.05), while there were significant differences in other indicators between groups ( P<0.05). Compared with traditional THA, robot assisted THA has more advantages in restoration of limb length and offset distance.

Thoracoscopic closure of atrial septal defect in perfused beating hearts.

This study aims to characterize the mid and long-term clinical outcomes of 856 atrial septal defect cases that underwent closure using MTCST without the assistance of a robotic system. From June 2009 to September 2023, a total of 856 cases at our center underwent selective repair of a secundum-type atrial septal defect using MTCST without Da Vinci robotic assistance. According to whether the operation was performed during an arrested heart or not, patients were divided into arrested heart group (n = 110) and beating heart group (n = 746). Cardiopulmonary bypass was established peripherally. Three-port incisions in the right chest were conducted first, followed by a pericardiotomy, superior and inferior vena cava snaring, atriotomy, and the closure of atrial septal defect under a thoracoscope. Patients were followed up from 3 months to 12 years postoperatively. The exclusively MTCST for atrial septal defect closure was successfully performed without any in-hospital mortality in both groups. None of the procedures required an alternative technique for the closure. There were significant learning curves for cardiopulmonary bypass time and operation time. No residual shunt was observed in all patients during the follow-up transthoracic echocardiography at 5-day and 3-month timepoints postoperatively. This study demonstrates that an exclusively MTCST for atrial septal defect repair is safe, simple, and minimally invasive. Exclusively MTCST is a new desirable alternative beside robotic-assisted atrial septal defect repair.

Expanding Applications and Future of Robotic Microsurgery.

Robotic-assisted microsurgery has emerged as a transformative technology, offering enhanced precision for complex procedures across various fields, including lymphatic surgery, breast reconstruction, trauma, and neurosurgery. This paper reviews current advancements, applications, and potential future directions for robotic-assisted microsurgery. In lymphatic surgery, robotic systems such as Symani have improved precision in thoracic duct reconstruction and lymphatic vessel anastomoses, reducing morbidity despite longer surgery times. In breast reconstruction, robotic systems are being used to refine techniques like the miraDIEP approach, minimizing tissue damage and enhancing precision in individualized treatments. Trauma reconstruction, particularly for extremities, has also benefited from robotic assistance, enabling successful sutures in small vessels and nerves. Emerging applications in meningeal lymphatics show potential for treating neurodegenerative diseases through improved drainage. In neurosurgery, robots enhance precision in deep and narrow anatomic spaces, although advancements in specialized instruments are needed for full implementation. Future development of robotic microsurgery systems will focus on improved maneuverability, miniaturization, and integration of tools like augmented reality and haptic feedback. The goal is to combine robotic precision, data storage, and processing with human skills such as judgment and flexibility. Although robots are unlikely to replace surgeons, they are poised to play an increasingly significant role in enhancing surgical outcomes. As the technology evolves, further research and clinical trials are needed to refine robotic systems and validate their expanding applications in clinical practice.

Comparison of robot-assisted versus fluoroscopically guided treatment of atlantoaxial dislocation in combination with high-riding vertebral artery: a preliminary study

BackgroundRobotic-assisted surgery has emerged as an innovative approach widely adopted in the field of orthopedics. However, its application specifically for managing atlantoaxial dislocation with a high-riding vertebral artery (AAD-HVA) remains underreported in the existing literature.ObjectiveTo compare the perioperative outcomes of robotic-assisted (RA) and fluoroscopic-guided free-hand (FH) techniques for atlantoaxial dislocation in combination with a high-riding vertebral artery (AAD-HVA).Study designThis was a retrospective study.SettingThis research was performed at a single department of spine surgery.MethodsData from patients who underwent atlantoaxial internal fixation between July 2018 and January 2022 at our hospital were retrospectively analyzed. Among the cases, 14 were performed using free-hand (FH) techniques and 11 utilized robotic-assisted (RA) techniques. Data collected included case notes, imaging records, and follow-up data. The reliability of screw placement was evaluated based on the Gertzbein and Robbins scores, while treatment outcomes were assessed using the Japanese Orthopaedic Association (JOA) score, visual analog scale (VAS), neck disability index (NDI), and postoperative complication rate.ResultsBaseline patient characteristics were comparable between the FH and RA groups. The mean blood loss was markedly lower in the RA group (157.3 ± 49.7 ml) compared to the FH group (290.0 ± 110.3 ml) (p = 0.03). Although the average operative time was slightly higher in FH group than in RA group, this disparity did not achieve statistical significance (p = 0.7588). Moreover, the radiation exposure dose was remarkably higher in FH group (32.7 ± 4.4 mGy) than in RA group (23.0 ± 3.2 mGy) (p < 0.0001). The percentage of clinically acceptable screw placement was slightly lower in FH group (87.5%) than in RA group (97.8%), but the observed variance was not statistically meaningful (p = 0.3669). Furthermore, the differences in JOA, VAS, and NDI scores between the FH and RA groups were not statistically significant. Additionally, no obvious differences were found in clinical outcomes or complications related to screw implantation between the two groups.LimitationsThis study has inherent limitations as it was retrospective in nature and conducted at a single center.ConclusionRobotic-assisted surgery for AAD-HVA patients offers a minimally invasive approach, reduced bleeding and lower radiation exposure compared with traditional free-hand surgery.

Technology-Based Interventions for Autism Spectrum Disorder: A Systematic Review

Introduction: Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder characterized by deficits in social communication and repetitive behaviors. Its prevalence has steadily increased, with the CDC reporting a rise from 1 in 100 children in 2006 to 1 in 44 in the United States by 2021. ASD manifests in a spectrum of symptoms, requiring tailored interventions to address each child's unique needs. Recent advancements in technology have shown promise in aiding children with ASD, particularly through robotics and socially assistive robots (SARs). This systematic review explores the impact of technology-based interventions on children with ASD, assessing their efficacy in enhancing social skills, communication, and behavior regulation. Methodology: This review followed PRISMA guidelines, screening 46,580 articles across databases such as PubMed, Cochrane, Science Direct, Google Scholar, and PsychInfo. After applying inclusion and exclusion criteria, 254 studies were selected for in-depth review. The review focused on technology-based interventions, including robotics and socially assistive robots, with MeSH terms such as "Technology," "Artificial Intelligence," "Autism Spectrum Disorder," and "ASD." Results: Technology-based interventions, particularly SARs, demonstrated significant improvements in social interaction, emotional regulation, and communication for children with ASD. Robots such as LEGO Mindstorms and "Kaspar" were effective in enhancing eye contact, cooperation, and emotional recognition. However, results varied depending on the type of technology used, study design, and participant characteristics. Conclusion: While technology-based interventions hold promise for children with ASD, further research is needed to standardize intervention protocols, dosage, and long-term outcomes. These tools offer a non-invasive, scalable solution for enhancing social and cognitive skills, but variability in study designs limits definitive conclusions. Keywords: Autism Spectrum Disorder, Technology, Robotics, Socially Assistive Robots, Communication, Cognitive Skills, Applied Behavioral Analysis

The Role of Robotics in Enhancing Precision and Outcomes in Orthopedic Surgery

The advent of robotics has significantly transformed orthopedic surgery, addressing challenges inherent in traditional manual techniques, such as variability in outcomes and precision limitations. Robotics enables millimeter-level accuracy, minimizes human error, and allows for personalized, minimally invasive procedures. Historical milestones, from the pioneering ROBODOC system in 1992 to advanced platforms like MAKO and ROSA, illustrate the progressive adoption of robotic systems, particularly in joint replacement and spine surgeries. Comparative studies demonstrate enhanced precision and reduced recovery times for robotic-assisted surgeries compared to conventional methods, with quantifiable improvements in alignment accuracy and postoperative outcomes. Key applications include joint arthroplasties, spinal surgeries, and complex trauma cases, where robotic assistance ensures accurate implant positioning, improved functional outcomes, and higher patient satisfaction rates. However, barriers such as cost, access disparities, and the learning curve persist. Emerging technologies, including artificial intelligence, augmented reality, and haptic feedback, are anticipated to further enhance robotic precision and broaden accessibility. As robotic systems become integral to orthopedic practice, ongoing advancements promise to elevate surgical standards, offering reliable, patient-specific solutions that improve both procedural consistency and quality of life.

Effects of Controlling Assist Robots to Follow Lumbar Load on Muscle Fatigue

ABSTRACTWe developed an assist robot that changes its assist force in real time according to the lumbar load estimated from the load information on the hand measured using a hand sensor device and the posture information. Furthermore, using the developed assist robot, the effect of the load‐following control on muscle fatigue was verified. The load was set at 6 and 1 kgf, and the amount of muscle activity in the lumbar region was measured using a muscle potential sensor during continuous flexion–extension exercises. The central frequency of the power spectrum was calculated as muscle fatigue, and its time trend was obtained. For comparison, similar experiments were also conducted without an assistive robot and with an existing assistive robot. Consequently, when load‐following control was used, muscle fatigue was reduced compared with existing assist robots in which the assist force was excessive in relation to the load. This shows the importance of load‐following control that is necessary to control the assist force according to the load when the assist robot is worn during work in which the load changes in a complex manner.

MINARO DRS: usability study of a robotic-assisted laminectomy.

Although the literature shows that robotic assistance can support the surgeon, robotic systems are not widely spread in clinics. They often incorporate large robotic arms adopted from the manufacturing industry, imposing safety hazards when in contact with the patient or surgical staff. We approached this limitation with a modular dual robot consisting of an ultra-lightweight carrier robot for rough prepositioning and small, highly dynamic, application-specific, interchangeable tooling robots. A formative usability study with N = 10 neurosurgeons was conducted using a prototype of a novel tooling robot for laminectomy to evaluate the system's usability. The participants were asked to perform three experiments using the robotic system: (1) prepositioning with the carrier robot and milling into (2) a block phantom as well as (3) a spine model. All neurosurgeons could perform a simulated laminectomy on a spine phantom using the robotic system. On average, they rated the usability of this first prototype already between good and excellent (SUS-Score above 75%). Eight out of the ten participants preferred robotic-assisted milling over manual milling. For prepositioning, the developed haptic guidance showed significantly higher effectiveness and efficiency than visual navigation. The proposed dual robot system showed the potential to increase safety in the operating room because of the synergistic hands-on control and the ultra-lightweight design of the carrier robot. The modular design allows for easy adaptation to various surgical procedures. However, improvements are needed in the ergonomics of the tooling robot and the complexity of the virtual fixtures. The cooperative dual robot system can subsequently be tested in a cadaver laboratory and in vivo on animals.

Comparison of robot-assisted, open, and laparoscopic-assisted surgery for cholangiocarcinoma: a network meta-analysis.

The aim of this study is to compare the efficacy of robot-assisted, laparoscopic-assisted and open surgery in the treatment of cholangiocarcinoma, and to evaluate the clinical effect of three surgical methods in the treatment of cholangiocarcinoma by network Meta-analysis. A systematical retrieval in PubMed and Web of Science was performed for relative literature on the effects of robot-assisted(RA), laparoscopy-assisted(LA), and open surgery(OA) for cholangiocarcinoma in treating cholangiocarcinoma. A literature search updated to September 1st, 2024, was performed. Studies have shown that the length of R0 resection, complication rate, 30-day mortality, Transfusion rate, Lymph Node Metastasis Rate, and hospital stay in RA are superior to LA and open surgery. The relative effectiveness of the three surgical methods in terms of operation time were: open surgery, laparoscope-assisted surgery, and robot-assisted surgery, and there was no significant difference among the three groups. Robot-assisted surgery is safe and feasible in the treatment of cholangiocarcinoma, but more clinical evidence is needed to confirm these findings.

Somatosensory integration in robot-assisted motor restoration post-stroke

Disruption of somatosensorimotor integration (SMI) after stroke is a significant obstacle to achieving precise motor restoration. Integrating somatosensory input into motor relearning to reconstruct SMI is critical during stroke rehabilitation. However, current robotic approaches focus primarily on precise control of repetitive movements and rarely effectively engage and modulate somatosensory responses, which impedes motor rehabilitation that relies on SMI. This article discusses how to effectively regulate somatosensory feedback from target muscles through peripheral and central neuromodulatory stimulations based on quantitatively measured somatosensory responses in real time during robot-assisted rehabilitation after stroke. Further development of standardized recording protocols and diagnostic databases of quantitative neuroimaging features in response to post-stroke somatosensory stimulations for real-time precise detection, and optimized combinations of peripheral somatosensory stimulations with robot assistance and central nervous neuromodulation are needed to enhance the recruitment of targeted ascending neuromuscular pathways in robot-assisted training, aiming to achieve precise muscle control and integrated somatosensorimotor functions, thereby improving long-term neurorehabilitation after stroke.

The Conversion of Unicompartmental Knee Arthroplasty to Total Knee Arthroplasty with Non-CT-Based Robotic Assistance: A Novel Surgical Technique and Case Series.

Robotic-assisted devices help provide precise component positioning in conversion of unicompartmental knee arthroplasty (UKA) to total knee arthroplasty (TKA). A few studies offer surgical techniques for computed tomography (CT) based robotic-assisted conversion of UKA to TKA; however, no studies to date detail this procedure utilizing a non-CT-based robotic-assisted device. This article introduces a novel technique employing a non-CT-based robotic-assisted device (ROSA Knee System, Zimmer Biomet, Warsaw, IN) for converting UKA to TKA with a focus on its efficacy in gap balancing. We present three patients (ages 46-66 years) who were evaluated for conversion of UKA to TKA for aseptic loosening, stress fracture, and progressive osteoarthritis. Each patient underwent robotic-assisted conversion to TKA. Postoperative assessments at 6 months revealed improved pain, function, and radiographic stability. Preoperative planning included biplanar long leg radiographs to determine the anatomic and mechanical axis of the leg. After arthrotomy with a standard medial parapatellar approach, infrared reflectors were pinned into the femur and tibia, followed by topographical mapping of the knee with the UKA in situ. The intraoperative software was utilized to evaluate flexion and extension balancing and plan bony resections. Then, the robotic arm guided placement of the femoral and tibial guide pins and the UKA components were removed. After bony resection of the distal femur and proximal tibia, the intraoperative software was used to reassess the extension gap, and plan posterior condylar resection to have the flexion gap match the extension gap. The use of a non-CT-based robotic-assisted device in conversion of UKA to TKA is a novel technique and a good option for surgeons familiar with robotic-assisted arthroplasty, resulting in excellent outcomes at 6 months.

Neuro Controlled Object Retrieval System

In this time of digitization and computerization, the life of individuals is getting more straightforward as nearly everything is programmed. This interconnection of the things can be used to help people with physical disabilities including paralysis. The brain signals of such people can be harnessed to create an object retrieval system. In this work, the concentration levels of such individuals are extracted using the EEG signals. These signals are then used to control the electronic devices. The designed system has been tested to control robotic car and arm using brain signals. These systems enable users to control external devices through neural signals, presenting significant potential in healthcare, robotics, and human-computer interaction. This paper reviews the development and implementation of a Neuro Controlled Object Retrieval System, which allows a user to control a robotic arm using brainwave patterns to pick up and retrieve objects. The system leverages Electroencephalography (EEG) signals to interpret neural activity, processed using machine learning algorithms to translate brain commands into physical actions. The objective of this review is to explore the existing methodologies, technologies, and challenges associated with such systems. The paper also discusses the potential applications, future advancements, and the significance of this technology in enhancing assistive robotics and rehabilitation tools.

ORGANA: A robotic assistant for automated chemistry experimentation and characterization

ORGANA: A robotic assistant for automated chemistry experimentation and characterization

Robotic assistance for upper cervical instrumentation: report on accuracy and safety.

This study aims to evaluate the accuracy and safety of C1 lateral mass and upper cervical pedicle screw placement assisted by the TiRobot II system. Ten patients who underwent cervical spine surgery assisted by the TiRobot II system were included. Screw accuracy was assessed using the Gertzbein-Robbins scale and by comparing the final screw positions with pre-planned trajectories. Deviations in screw tip, tail, and angle were recorded. Clinical data, including symptoms, surgical outcomes, and postoperative follow-up, were collected. Neurological improvement was evaluated using pre- and post-operative mJOA scores, with recovery rates calculated by Hirabayashi's method to assess outcomes 3months after surgery. A total of 30 screws were placed in 10 patients. All screws (30/30) were within the clinically acceptable range, with 93.33% (28 screws) classified as Grade A and 6.67% (2 screws) as Grade B. In the sagittal plane, the average tip deviation was 1.82 ± 0.79mm, tail deviation 1.64 ± 0.60mm, and angular deviation 1.92 ± 1.39°. In the axial plane, tip deviation was 1.96 ± 0.87mm, tail deviation 1.92 ± 0.65mm, and angular deviation 2.01 ± 1.07°. The average surgery time was 318.80 ± 66.07min, with a mean EBL of 205.00 ± 55.03mL. Postoperative mJOA scores significantly improved from 8.10 ± 1.97 to 12.60 ± 1.78 (p < 0.05), with a 52 ± 14% recovery rate. All patients showed significant symptom improvement. The TiRobot II system demonstrates the capability to precisely execute pre-planned trajectories and improves the accuracy and safety of C1 lateral mass and upper cervical screw placement.

Robotic spine systems: overcoming surgeon experience in pedicle screw accuracy: a prospective study.

Prospective single-center study. To compare the accuracy of pedicle screws placed by freehand and under fluoroscopy and robotic assistance with intraoperative image acquisition. Pedicle screws are the most commonly used spinal anchors owing to their ability to stabilize all three spinal columns. Various techniques such as freehand, fluoroscopy-assisted, and navigation-assisted pedicle screw placements have been used with varying degrees of accuracy. Most studies on robotic-assisted pedicle screw placement have utilized preoperatively acquired computed tomography scans. To our knowledge, this is the only study in the literature that compared freehand with fluoroscopy-guided and robotic-assisted pedicle screw insertion with freehand and fluoroscopy. In this prospective study, a total of 1,120 pedicle screws were placed in the freehand group (n=175), 1,250 in the fluoroscopyassisted group (n=172), and 1,225 in the robotic-assisted group (n=180). Surgical parameters and screw accuracy were analyzed between the three groups. The preoperative plan overlapped with the postoperative O-arm scan to determine if the screws were executed as planned. The frequency of clinically acceptable screw placement (Gertzbein-Robbins grades A and B) in the freehand, fluoroscopy-assisted, and robotic-assisted groups were 97.7%, 98.6%, and 99.34%, respectively. With robotic assistance, an experience-neutralizing effect implied that surgeons with varying levels of experience achieved comparable pedicle screw accuracy, blood loss, O-arm time, robot time, and time per screw. No significant difference in these parameters was found between surgeries commencing before and after 2 PM. No significant differences were noted between the planned and executed screw trajectories in the robotic-assisted group irrespective of surgical experience. The third-generation robotic-assisted pedicle screw placement system used in conjunction with intraoperative threedimensional O-arm imaging consistently demonstrates safe and accurate screw placement with an experience-neutralizing effect.

Robotic assistants for the rehabilitation of communication disorders in children: A proposal based on MTO manufacturing for developing countries

Language is fundamental to human communication, allowing individuals to express and exchange ideas, thoughts, and emotions. In early childhood, some children experience communication disorders that impede their ability to articulate words correctly, posing significant challenges to their learning and development. This issue is exacerbated in developing countries, where limited resources and a lack of technological tools hinder access to effective speech therapy. Traditional speech therapy remains vital, but the latest technological advancements have introduced robotic assistants to enhance therapy for communication disorders. Despite their potential, these technologies are often inaccessible in developing regions due to high production costs and a lack of sustainable manufacturing models. For these reasons, this paper presents “FONA,” a robotic assistant that employs rule-based expert systems to provide tactile, auditory, and visual stimuli. FONA supports children aged 3 to 6 in speech therapy by delivering exercises such as syllable production, word formation, and pictographic storytelling of various phonemes. Notably, FONA was successfully tested on children with cochlear implants, reducing the number of sessions required to produce isolated phonemes. The paper also introduces an innovative analysis of the Make To Order (MTO) manufacturing system for producing FONA in developing countries. This analysis explores two key perspectives: collaborative networks and entrepreneurship, offering a sustainable production model. In a pilot experiment, FONA significantly improved children’s attention spans, increasing the period by 17 min. Furthermore, the economic analysis demonstrates that producing FONA through collaborative networks can significantly reduce costs, making it more accessible to institutions in developing countries. The findings suggest that the project is viable for a five-year period, providing a sustainable and effective solution for addressing communication disorders in children.

Integrating subject-specific workspace constraint and performance-based control strategy in robot-assisted rehabilitation.

The robot-assistive technique has been widely developed in the field of neurorehabilitation for enhancement of neuroplasticity, muscle activity, and training positivity. To improve the reliability and feasibility in this patient-robot interactive context, motion constraint methods and adaptive assistance strategies have been developed to guarantee the movement safety and promote the training effectiveness based on the user's movement information. Unfortunately, few works focus on customizing quantitative and appropriate workspace for each subject in passive/active training mode, and how to provide the precise assistance by considering movement constraints to improve human active participation should be further delved as well. This study proposes an integrated framework for robot-assisted upper-limb training. A human kinematic upper-limb model is built to achieve a quantitative human-robot interactive workspace, and an iterative learning-based repulsive force field is developed to balance the compliant degrees of movement freedom and constraint. On this basis, a radial basis function neural network (RBFNN)-based control structure is further explored to obtain appropriate robotic assistance. The proposed strategy was preliminarily validated for bilateral upper-limb training with an end-effector-based robotic system. Experiments on healthy subjects are enrolled to validate the safety and feasibility of the proposed framework. The results show that the framework is capable of providing personalized movement workspace to guarantee safe and natural motion, and the RBFNN-based control structure can rapidly converge to the appropriate robotic assistance for individuals to efficiently complete various training tasks. The integrated framework has the potential to improve outcomes in personalized movement constraint and optimized robotic assistance. Future studies are necessary to involve clinical application with a larger sample size of patients.

Staging Accuracy and Prognostic Value of Prostate-Specific Membrane Antigen PET/CT Strongly Depends on Lymph Node Tumor Burden.

Objectives: To explore the factors affecting the lymph node metastasis (LNM) detection performance of prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA PET/CT) and to evaluate its prognostic value for biochemical recurrence after radical prostatectomy (RP). Methods: Patients who had intermediate- or high-risk prostate cancer and underwent robot-assisted (RA)RP between 2017 and 2021 were included. Initial lymph node staging was carried out using PSMA PET/CT. Sensitivity, specificity, and positive (PPV) and negative (NPV) predictive values were calculated. A cut-off value for LNM tumor deposit size that maximizes specificity was investigated and a post hoc specificity analysis was carried out. In survival analysis for biochemical progression-free survival (bPFS) after RP, Kaplan-Meier curves of molecular imaging (mi)N0 and miN1 patients were compared using the log-rank test and separate Cox regression models were developed to reveal the significance of PSMA PET/CT staging in pre- and post-surgery settings. Results: In 583 patients with a prevalence of pathology-proven LNM of 27.4%, overall sensitivity, specificity, PPV, and NPV of PSMA PET/CT per patient were 26.3% [95%CI 18.9-35.5], 93.9% [95%CI 84.9-100], 61.8% [95%CI 44.5-83.5], and 77.1% [95%CI 69.7-85.1], respectively. PSMA PET/CT showed a better sensitivity as LNM tumor deposit size increased (p = 0.003 OR 2.4 [95%CI 1.3-4.4]) and a better specificity in pT3-4 tumors (96.1%) versus pT2 (91.1%, p = 0.024 OR 2.7 [95%CI 1.1-6.3]). After adjustment according to 5.5 mm LNM tumor deposit size, which showed the best discriminative performance (AUC: 0.905 [95%CI 0.804-1.000, p < 0.001]), overall sensitivity tripled (90.2%, p < 0.001). The 1-year bPFS was 56.0% and 83.3% for miN1 and miN0 patients, respectively (p < 0.001). Whereas miN0pN1 was not, miN1pN1 disease was independently associated with decreased bPFS (HR:2.1 95%CI 1.3-3.4, p < 0.001). Conclusions: PSMA PET/CT has a lymph node tumor burden-dependent and cohort-driven diagnostic ability but consequently a strong independent prognostic value for predicting biochemical recurrence after RARP.

Does robotic surgical assistant (ROSA) functionally aligned TKA lead to higher satisfaction than conventional mechanically aligned TKA: A propensity-matched pair analysis

ObjectivesTotal knee arthroplasty (TKA) is the established treatment for severe knee osteoarthritis, with robotic-assisted TKA (rTKA) proposed to enhance surgical precision and potentially improve outcomes. This study investigates whether functionally-aligned rTKA using the ROSA Knee System results in superior functional outcomes and patient satisfaction compared to conventional mechanically aligned TKA (mTKA). MethodsWe conducted a retrospective, propensity-score matched cohort study including 154 patients (46 rTKA, 108 mTKA) who underwent primary TKA by a single surgeon from October 2020 to October 2023. Functionally-aligned (FA) rTKA was performed using the ROSA Knee System. Patients were assessed using the Short-Form 36 (SF36), Knee Society Knee Score (KSKS), Knee Society Function Score (KSFS), and Oxford Knee Score (OKS) preoperatively and at 6 months postoperatively. Immediate postoperative outcomes such as pain at rest and movement, ambulation distance, and range of motion were measured. Statistical analysis evaluated results at a 95 % confidence interval, with significance at P < 0.05. ResultsNo significant differences were observed in immediate postoperative pain at rest (P = 0.988), pain during movement (P = 0.634), ambulation distance (P = 0.243), and range of motion (P = 0.752) between the groups. At 6 months, there were no significant differences between rTKA and mTKA in achieving the minimal clinically important difference for SF36 (P = 0.996), KSKS (P = 0.150), KSFS (P = 0.091), and OKS (P = 0.949). No significant differences were noted for satisfaction levels (P = 0.315) and fulfilled expectations (P = 0.557) between both groups. ConclusionsAt 6 months postoperatively, FA rTKA demonstrated equivalent outcomes and satisfaction levels compared to mTKA. Future research should focus on examining longer-term follow-up outcomes, quantifying gap balance in MA mTKA to allow direct comparison with rTKA and studying alternative personalised alignment rTKA strategies to enhance patient outcomes.