UNASSIGNED: One of the most debated topics in modern total knee arthroplasty (TKA) is the impact of metal hypersensitivity (MH) as a potential cause of prosthesis failure. Implanting hypoallergenic prostheses to avoid potential problems in suspected cases of MH is one treatment option that can be used in such cases. However, their long-term clinical safety and efficacy are not well proven.
UNASSIGNED: All literature relevant to modern hypoallergenic implants were reviewed and summarized to provide a comprehensive synopsis. In addition, a detailed literature search was performed on PUBMED, MEDLINE, and Google Scholar to identify all the clinical studies reporting outcomes for hypoallergenic knee implants. Our search was confined to those studies published as full manuscripts in the English language from July 2018 to July 2023.
UNASSIGNED: To minimize the risk of MH, new implant variants have been developed which are either under clinical evaluation or in routine clinical use. These include conventional metal implants with protective coatings (mono- or multilayer) and metal-free implants. However, there is insufficient clinical data to confirm the rationale and effectiveness of using these \"hypoallergenic\" TKA implants.
UNASSIGNED: Published studies and arthroplasty registry data analyses indicate no significant differences between hypoallergenic and standard TKAs with overall good survival rates. In the future, further high-quality studies are needed to better understand the complexity of this subject.

BACKGROUND: Knee arthritis is a destructive disorder that affects the knee joints and causes pain and reduced mobility. Drug treatments, weight loss, and exercise control the symptoms of the disease, but these methods only delay the disease process and eventually, knee joint replacement surgery will be needed. After surgery, with the help of a proper physiotherapy program, full recovery takes an average of 6-12 months. However, currently, there is no similar tool to facilitate this process in Iran.
OBJECTIVE: The purpose of this research is to design and develop the prototype of a rehabilitation system for patients after knee replacement surgery, which provides patients with information and appropriate physiotherapy programs.
METHODS: This study was development-applied and was done in three stages. In the first stage, the needs and content of education and therapeutic exercises were prepared in the form of a checklist, and then the necessity of each item was checked in the evaluation sessions. In the second stage, the prototype of the system was developed using Adobe XD software and based on the requirements approved from the previous stage. In the third stage, the usability of the program was analyzed from the point of view of experts using the exploratory evaluation method with Nielsen\'s 13 principles of usability.
RESULTS: At first, the system requirements were extracted and prepared in two checklists of content (51 exercises) and capabilities (60 items). Then after a survey of experts based on the Delphi technique, content information (43 exercises) and functional and non-functional requirements (53 items) were obtained. A survey of experts helped to finalize the information elements, categorize them, and prepare the final version of the checklists. Based on this, the system requirements were classified into 11 categories, and the training content was classified into 3 training periods. Finally, the design and development of the system was done. This system has admin, physician, and patient user interfaces. The result of usability showed that this system is efficient and there are only a few problems in the feature of helping users to detect and recover from errors.
CONCLUSIONS: It seems necessary to develop a system based on the principles of usability by therapists and rehabilitation specialists to train and monitor the remote rehabilitation process of patients after knee joint replacement at home. And the importance of involving stakeholders in the design and development of remote rehabilitation systems is not hidden from anyone. Kara system has all of the above.

Background and Objectives: As a treatment modality for advanced knee osteoarthritis, total knee arthroplasty is well established and has been performed on many patients over time. To improve surgical outcomes, fixed-bearing implant insertion with robotic-assisted TKA has been introduced; however, the insertion of mobile-bearing (MB) implants with the same method is challenging. The aim of this study was to compare the short-term postoperative follow-up outcomes of MB implant insertion using a robotic-assisted TKA system and conventional TKA. Materials and Methods: We investigated functional improvement in the knees of 60 patients who underwent the insertion of MB implants using either robotic-assisted TKA or conventional TKA. Isokinetic muscular function, range of motion, the Western Ontario and McMaster Universities Osteoarthritis Index score, visual analog scale (VAS) score, and Knee Society Score (KSS) were measured 6 months after surgery. The statistical analysis of outcome measurements was performed using the Mann-Whitney U test and the Wilcoxon signed-rank test. Results: Some isokinetic muscular functions, as well as Knee Society Scores (pain and function) and VAS scores, were significantly higher in patients who underwent MB insertion with robotic-assisted TKA than in those who underwent conventional TKA. Conclusions: When an MB implant is inserted using a robotic-assisted TKA system, a better surgical outcome can be expected.

UNASSIGNED: Previous epidemiological studies have indicated an increased risk of neurovascular diseases in patients following total hip and knee replacements. However, definitive conclusions regarding the increased risk of stroke post-replacement remain elusive. Therefore, we conducted a two-sample Mendelian randomization study to investigate the causal relationship between total hip and knee replacements and stroke.
UNASSIGNED: We utilized summary data from publicly available genome-wide association studies (GWAS). Data concerning total hip replacements (THR, N = 319,037) and total knee replacements (TKR, N = 252,041) were sourced from the Genetics of Osteoarthritis (GO) Consortium. Stroke-related data were obtained from the International Stroke Genetics Consortium, encompassing any stroke (AS), any ischemic stroke (AIS), large vessel ischemic stroke (LV-IS), cardioembolic ischemic stroke (CE-IS), and small vessel ischemic stroke (SV-IS). Our primary causal inference method was the inverse variance weighted (IVW) approach, supplemented by weighted median and MR-Egger regression as secondary inference methods. We utilized the MR-PRESSO global test for outlier detection, Cochran\'s Q statistic to assess heterogeneity, and assessed the multiplicity and stability of our findings using p-values from MR-PRESSO and MR-Egger regressions, and the leave-one-out method, respectively.
UNASSIGNED: We identified significant genetic associations between THR and both AS (IVW p = 0.0001, OR = 1.08, 95% CI = 1.04-1.12) and AIS (IVW p = 0.0016, OR = 1.07, 95% CI = 1.03-1.12). Significant associations were also observed between TKR and AS (IVW p = 0.0002, OR = 1.08, 95% CI = 1.04-1.12), as well as AIS (IVW p = 0.0005, OR = 1.15, 95% CI = 1.06-1.24).
UNASSIGNED: Our findings genetically support an increased risk of stroke following total hip and knee replacements. However, further studies are necessary to elucidate the specific mechanisms underlying stroke episodes post-replacement.

UNASSIGNED: Although total knee replacement (TKR) surgery has succeeded in improving pain and deformity, a proportion of patients remain incompletely satisfied with their outcome. This prospective study aims to assess the survivorship, clinical, and radiological outcomes using a novel \'kinematic retaining\' (KR) implant.
UNASSIGNED: 156 patients underwent TKR surgery for primary osteoarthritis using the Physica KR implant at three European Centres. Patients were followed up for five years using both radiographic and clinical evaluations.
UNASSIGNED: Within 6 months post-operatively, 79.4% and 85.9% had good-excellent clinical and functional KSS values, this was maintained to 76.9% and 79.5% at five years. Mean Knee Society Score (KSS) improvement at 5 years was 32.8 (from 23 to 40) and 37.4 (from 30 to 50) (p < 0.01). All Knee Injury and Osteoarthritis Outcome Score (KOOS) sub-scores showed statistically significant improvement from before surgery at a mean of 34.7 (SD ± 16.1) to a mean of 86.6 (SD ± 16.1) at five years. The mean Oxford Knee Score (OKS) was 43.7 (±5.6), with over 80% of the patients having a good-excellent outcome at five years. OKS improved significantly by six weeks after surgery (p < 0.01) and remained constant throughout the 5-year follow-up. Visual Analogue Score (VAS) Satisfaction scores improved significantly after the post-operative time point of six weeks. From 1 year to 5 years, the average VAS was over 85 mm. The Forgotten Joint Score (FJS) increased from 64.5 at 1 year to 79.2 at 5 years after surgery (p < 0.01). No progressive adverse radiographic features were noted. Two patients were revised during the study period: one for infection and the other for aseptic loosening.
UNASSIGNED: This novel \'kinematic retaining\' knee prosthesis has shown exceptional clinical and patient-reported improvements, with a remarkable 99.4% survivorship (95.5-99.9) at five years.

Introduction: The formation of bacterial biofilms on knee arthroplasty implants can have catastrophic consequences. The aim of this study was to analyze the effectiveness of the bioelectric effect in the elimination of bacterial biofilms on cultivated knee arthroplasty implants. Methods: A novel device was designed to deliver a bioelectric effect on the surface of knee arthroplasty implants. 4-femoral prosthetic implants were cultivated with a staphylococcus aureus inoculum for 15 days. The components were divided into four different groups: A (not treated), B (normal saline 20-minutes), C (bioelectric effect 10-minutes), D (bioelectric effect 20-minutes). The implants were sonicated, and the detached colonies were quantified as the number of colony-forming unit (CFUs). The implants were sterilised and the process was repeated in a standardized manner four more times, to obtain a total of five samples per group. Results: The number of the CFUs after a 10-minute exposure to the bioelectric effect was of 208.2 ± 240.4, compared with 6,041.6 ± 2010.7 CFUs in group A, representing a decrease of 96.5% ± 4.3 (p = 0.004). And a diminution of 91.8% ± 7.9 compared with 2,051.0 ± 1,364.0 CFUs in group B (p = 0.109). The number of bacterial colonies after a 20-minute exposure to the bioelectric effect was 70 ± 126.7 CFUs, representing a decrease of 98.9% ± 1.9 (p = 0.000) compared with group A. And a decrease of 97.8% ± 3.0 (p = 0.019) compared with group B. Conclusions: The bioelectric effect was effective in the elimination of bacterial biofilm from knee arthroplasty implants. This method could be used in the future as part of conventional surgical procedures.

BACKGROUND: With the increasing number of joint replacement surgeries, periprosthetic joint infection (PJI) has become a significant concern in orthopedic practice, making research on PJI prevention paramount. Therefore, the study will aim to compare the effect of combined usage of povidone-iodine and topical vancomycin powder to the use of povidone-iodine alone on the PJI incidence rate in patients undergoing primary total hip (THA) and total knee arthroplasty (TKA).
METHODS: The prospective randomized clinical trial will be conducted in two independent voivodeship hospitals with extensive experience in lower limb arthroplasties. The studied material will comprise 840 patients referred to hospitals for primary THA or TKA. The patients will be randomly allocated to two equal groups, receiving two different interventions during joint replacement. In group I, povidone-iodine irrigation and consecutively topical vancomycin powder will be used before wound closure. In group II, only povidone-iodine lavage irrigation will be used before wound closure. The primary outcome will be the incidence rate of PJI based on the number of patients with PJI occurrence within 90 days after arthroplasty. The occurrence will be determined using a combined approach, including reviewing hospital records for readmissions and follow-up phone interviews with patients. The infection will be diagnosed based on Musculoskeletal Infection Society criteria. The chi-square test will be used to compare the infection rates between the two studied groups. Risk and odds ratios for the between-groups comparison purposes will also be estimated. Medical cost analysis will also be performed.
CONCLUSIONS: A randomized clinical trial comparing the effect of combined usage of povidone-iodine irrigation and vancomycin powder to the use of povidone-iodine irrigation alone in preventing PJIs after primary arthroplasty is crucial to advancing knowledge in orthopedic surgery, improving patient outcomes, and guiding evidence-based clinical practices.
BACKGROUND: ClinicalTrials.gov NCT05972603 . Registered on 2 August 2023.

The diagnosis of periprosthetic joint infections (PJI) presents a formidable challenge to orthopaedic surgeons due to its complex and diverse manifestations. Accurate diagnosis is of utmost importance, as even mild pain following joint replacement surgery may indicate PJI in the absence of a definitive gold standard diagnostic test. Numerous diagnostic modalities have been suggested in the literature, and international societies have continually updated diagnostic criteria for this debilitating complication. This review article aims to comprehensively examine the latest evidence-based approaches for diagnosing PJI. Through a thorough analysis of current literature, we explore promising diagnostic strategies that have demonstrated effectiveness in identifying PJI. These strategies encompass the utilization of laboratory markers, such as erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), alongside imaging techniques such as magnetic resonance imaging (MRI) and leukocyte scintigraphy. Additionally, we highlight the importance of synovial fluid analysis, including the potential role of alpha-defensin as a biomarker, and examine evolving international diagnostic criteria to standardize and improve diagnostic accuracy.

UNASSIGNED: Arthroplasty registers can provide feedback information on the results of arthroplasties performed by a certain institution or surgeon. The use of real-world data to achieve real-world evidence can help evaluate the performance of the implants used and help counsel our patients. The main objective of our study was to determine the survivorship of the total knee implant we are currently using.
UNASSIGNED: A retrospective cohort study of patients who received a total knee arthroplasty from January 2009 to December 2020 in our hospital was conducted, using data from the Catalan arthroplasty registry and the Catalan health service database. Demographic and surgical data were analysed using the Kaplan-Meier method, log-rank test and Cox proportional hazards models with the R Project software (p < 0.05).
UNASSIGNED: A total of 1336 total knee arthroplasties were included in the study, of which 992 were women. The causes for revision included aseptic loosening (17), infection (29), instability (13), patellar implantation (13), arthrofibrosis (5) and quadriceps tendon rupture (1).The cumulative risk for revision at 5 years using the Kaplan-Meier method was 6.0% and at 10 years 6.5%. Considering gender, this risk was 7.0% and 7.5% at 5 and 10 years, respectively, in women and 3.3% in men, both at 5 and 10 years (p = 0.009). A higher risk for revision in women was seen, which is considered statistically significant (p = 0.012).
UNASSIGNED: Our survivorship results are comparable to those published in the literature, but with a higher revision risk in women that is only statistically significant for the whole group of reoperations and for patellar implantation, but not for the rest of the diagnoses.
UNASSIGNED: Level IV.

Robotic total knee replacement (TKR) surgery has evolved over the years with the aim of improving the overall 80% satisfaction rate associated with TKR surgery. Proponents claim higher precision in executing the pre-operative plan which results in improved alignment and possibly better clinical outcomes. Opponents suggest longer operative times with potentially higher complications and no superiority in clinical outcomes alongside increased costs. This editorial will summarize where we currently stand and the future implications of using robotics in knee replacement surgery.