Complications and downsides of the robotic total knee arthroplasty: a systematic review

Comparative Efficacy and Precision of Robot-Assisted vs. Conventional Total Knee Arthroplasty: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background/Objectives: Total knee arthroplasty (TKA) is a common procedure for knee osteoarthritis. While conventional TKA (C-TKA) remains standard, robot-assisted TKA (RA-TKA) has been introduced to enhance implant positioning and clinical outcomes. However, its comparative benefits remain unclear. This systematic review and meta-analysis compared RA-TKA with C-TKA, examining the influence of robotic system, surgeon experience, and follow-up duration. Methods: A systematic search was conducted across the PubMed, Scopus, Web of Science, and Cochrane Library databases. Randomized controlled trials (RCTs) comparing RA-TKA with C-TKA were included. Outcomes were categorized into clinical, radiographic, and safety endpoints. Subgroup and meta-regression analyses explored factors influencing outcome variability, including robotic system, number of surgeons, and follow-up duration. Results: Twenty-five RCTs (5614 patients) were analyzed. RA-TKA showed modest improvements in clinical outcomes, such as KSS and VAS pain scores, but results varied across subgroups. RA-TKA demonstrated a significantly better flexion range of motion (ROM) in certain countries (e.g., Russia, MD = 10; 95%CI: 5.44, 14.56) and with specific robotic systems (e.g., NAVIO). No significant differences were found in OKS and HSS scores. Radiographic outcomes, including the HKA Angle, varied by robotic system, with NAVIO and YUANHUA showing better alignment than C-TKA. Complication rates were comparable, though RA-TKA had a higher risk of conversion to open surgery (10% vs. 2%). Meta-regression identified robotic system and surgeon experience as key predictors of outcome variability. Conclusions: RA-TKA offers advantages in implant alignment and postoperative pain reduction. However, benefits are inconsistent across settings, and some robotic systems may not provide improvements over C-TKA.

Navigated versus conventionally instrumented total knee arthroplasty techniques: No difference in functional alignment or balance

PURPOSE

Much debate exists about the superiority of navigated versus conventional instrumentation for achieving optimal balance and alignment during total knee arthroplasty (TKA). Recent registry data indicate no long-term survivorship benefit for TKAs performed using technology assistance, despite the added resource and financial costs. However, outcome comparisons are confounded by varying surgeon techniques and targets for ideal balance and alignment. This study aimed to investigate alignment or balance outcome differences between navigated and conventionally instrumented TKAs performed using an identical operative sequence and alignment strategy.

METHODS

Fifty navigated and 50 conventionally instrumented primary TKAs, using an identical inverse kinematic alignment strategy, were included. Navigation equipment was used intraoperatively to 'post-cut' record the conventionally instrumented TKAs. Intraoperative balance, range, and alignment; and post-operative radiographic accuracy for restoration of constitutional alignment were compared.

RESULTS

Forty-nine navigated and 49 conventionally instrumented TKAs were compared (n = 2 excluded due to inadequate radiographs). No preoperative demographic or deformity severity differences existed. No intraoperative balance, range or alignment difference existed. Neither technique was more accurate for restoration of constitutional alignment.

CONCLUSION

Whilst large registry data may be confounded by uncaptured variables such as surgeon balancing techniques or surgeon alignment strategy preferences, this study found no alignment or balance differences between navigated versus conventionally instrumented TKA techniques for a surgeon and technique-controlled study. Although the increased resources necessary for technology assistance are not justified by this study, further studies may identify significance using larger samples or comparison of alternative outcomes.

LEVEL OF EVIDENCE

Level II.

Cemented and Cementless Robotic-Assisted versus Manual Total Knee Arthroplasty Outcomes: A Single Center Michigan Arthroplasty Registry Collaborative Quality Initiative-Based Study

BACKGROUND

The purpose of our study was to determine whether a difference existed between cemented and cementless robotic-assisted total knee arthroplasty (RA-TKA) and manual TKA with regard to revision rates and 90-day outcomes. We hypothesized these techniques would have similar results.

METHODS

A single center's data from the Michigan Arthroplasty Registry Collaborative Quality Initiative were queried for all primary TKAs from January 2012 to July 2023. The RA-TKA and manual cohorts were compared for revisions and 90-day complications, including emergency department (ED) visits, readmissions, and returns to the operating room Chi-square and Fisher's exact tests were used for categorical data, and t-tests for continuous data. Of the 7,417 cemented TKAs (mean age 67 ± 9.6 years, 70% women), 273 were RA-TKA and 7,144 were manual. Of the 2,407 cementless TKAs (mean age 65 ± 8.6 years, 53% women), 730 were RA-TKA and 1,677 were manual.

RESULTS

Cemented RA-TKA had more periprosthetic joint infection revisions, more 90-day ED visits, and readmissions for wound complications compared to cemented manual TKA. Cementless RA-TKA had more 90-day readmissions for wound complications, while manual TKA had more 90-day ED visits for postoperative pain. Cemented and cementless RA-TKA had longer surgical time, shorter length of stay, and shorter time to revision. There were 283 revisions performed on cemented manual TKA (nine RA-TKAs, 3.2%, 274 manual, 3.8%, (P = 0.87)). There were 56 revisions performed on cementless knees (13 RA-TKAs, 1.7%, 43 manual 2.5% (P = 0.303)). Cumulative percent revision at 5 years was 3.9% for cemented RA-TKA, 3.5% for cemented manual TKA, 1.8% for cementless RA-TKA, and 2.8% for cementless manual TKA.

CONCLUSIONS

Both RA-TKA and manual TKA have similar revision rates, while RA-TKA had more wound complications. Cementless RA-TKA may be beneficial in reducing postoperative pain.

Redefining Knee Arthroplasty: Does Robotic Assistance Improve Outcomes Beyond Alignment? An Evidence-Based Umbrella Review

Background: Robotic-assisted total knee arthroplasty (rTKA) has been introduced to improve surgical precision and alignment in knee replacement procedures. However, its impact on clinical outcomes, pain relief, and cost-effectiveness remains debated. This umbrella review synthesizes evidence from systematic reviews and meta-analyses comparing rTKA to conventional TKA. Methods: An umbrella review was conducted in PubMed, Scopus, Web of Science, Embase, and the Cochrane Database of Systematic Reviews. Systematic reviews and meta-analyses comparing rTKA with conventional TKA were included. Methodological quality was assessed using AMSTAR 2 and ROBIS tools. Primary outcomes included hospital stay, radiographic alignment, postoperative pain, functional outcomes, and patient satisfaction. Results: Ten systematic reviews were included. rTKA demonstrated superior alignment accuracy and a reduction in alignment outliers. Some studies reported shorter hospital stays and lower early postoperative pain scores for rTKA. However, these benefits did not consistently translate into improved long-term functional outcomes, patient satisfaction, or reduced revision rates. Cost-effectiveness analyses indicated that rTKA remains an expensive option, with benefits largely dependent on surgical volume and healthcare system resources. Conclusions: While rTKA improves surgical precision and may offer short-term advantages, its long-term superiority over conventional TKA remains unproven. Higher costs and longer operative times limit its widespread adoption. Further high-quality, long-term studies are needed to determine its clinical and economic value.

Survivorship in robotic total knee arthroplasty compared with conventional total knee arthroplasty: A systematic review and meta-analysis

BACKGROUND

Total knee arthroplasty (TKA) is the gold standard surgical management for end-stage knee osteoarthritis (OA). Robotic TKA (rTKA) was developed to improve bone preparation accuracy and increase reproducibility. In many settings internationally, rTKA systems have significantly higher costs for patients, and survivorship outcomes are unclear. There are several prior meta-analyses, but these focused on clinical and radiologic outcomes, and to our knowledge, none have evaluated survival. Differences in survival between semi-active or active robotic systems are also not well investigated.

STUDY DESIGN

Meta-analysis.

METHODS

A random-effects meta-analysis was conducted on comparative studies between robotic-assisted TKAs and conventional TKAs (cTKAs) in patients undergoing TKA for primary knee OA. We searched MEDLINE, Embase, Cochrane Library, and SCOPUS from inception to 19 December 2024. Outcomes assessed were the implant survival in robotic-assisted TKA compared to conventional methods in standard primary knee OA cases, with subgrouping between active and semi-active systems performed. Secondary outcomes included associated complications, post-operative pain scores, and functional outcomes.

RESULTS

A total of 20 comparative studies were included in the meta-analysis. Among them, 2,804 patients underwent cTKA, while 2,599 underwent rTKA. At two years, the pooled survivorship rate was 97.9% (95% CI: 96-99) in the conventional group and 98.3% (95% CI: 96.2-99.2) in the robotic group. There were no significant differences between the groups (P = 0.7). There were no significant differences between the robotic (semi-active) group and the conventional group (P = 0.5) on further unpaired T-Testing. Between 2 and 5 years, pooled survivorship rates in the conventional group were 96.8% (95% CI: 90.3-99) and 97.1% (95% CI: 91.3-99) in the robotic group. There were no significant differences between groups (P = 0.9). At ten years postoperatively, pooled survivorship rates in the conventional group were 96.9% (95% CI: 95-98) and 97.8% (95% CI: 96.7-98.5) in the robotic group. There were no significant differences between the groups (P = 0.3).

CONCLUSION

Conventional TKA is non-inferior to rTKA at short and long-term follow-up with regard to implant survival, complications, and postoperative pain scores, while rTKA shows subtle improvements in functional outcome measures.

TRIAL REGISTRATION

CRD42024540997.

Femoral resection accuracy and precision in manual caliper-verified kinematic alignment total knee arthroplasty

Introduction

The accuracy and precision of bone resections in total knee arthroplasty (TKA) are essential to avoid poor implant positioning, which can lead to component wear, pain, and instability, reducing patient satisfaction and implant survivorship. Technology-assisted TKA techniques aim to improve accuracy but come with added costs, increased operative time, and varying success in clinical outcomes. Caliper-verified kinematic alignment (KA) attempts to restore the joint line by precisely measuring resections to equal implant thickness. We evaluated the accuracy and precision of caliper-verified KA-TKA performed with manual instruments. We hypothesised that this technique would achieve high accuracy and precision, with an average absolute difference between actual and target distal and posterior femoral resection measurements of ≤ 0.5 mm.

Methods

385 consecutive patients underwent primary unrestricted caliper-verified KA-TKA with manual instrumentation. The thickness of the distal medial (DM), distal lateral (DL), posterior medial (PM) and posterior lateral (PL) femoral condyle resections were measured with a caliper and compared to a target determined by the degree of cartilage loss, saw blade kerf, and femoral component thickness.

Results

The mean differences between the resected and target thicknesses for DM, DL, PM and PL femoral resections were 0.1 ± 0.2 mm, 0.1 ± 0.3 mm, 0.3 ± 0.5 mm and 0.2 ± 0.4 mm, respectively (mean ± std. dev.). Most femoral resections were within 0.5 mm of the target-97.7%, 94.5%, 85.7% and 89.4% of DM, DL, PM and PL resections, respectively.

Conclusion

Manual caliper-verified KA-TKA achieved highly accurate and precise femoral resections with absolute differences from target that averaged 0.175 mm. This simple, logical, efficient, and reproducible surgical technique may be an option for surgeons contemplating the use of technology-assisted options, such as patient-specific instrumentation or robotic arm-assisted TKA, and surgeons without access to such technologies.

Level of Evidence

Level II.

Modified Macroscopic Soft Tissue Injury (Modified MASTI) Classification for Bone and Soft Tissue Integrity in Cruciate Retaining Total Knee Arthroplasty

Background

The purpose of this study was to develop a 'modified macroscopic soft tissue injury (MASTI) classification' for cruciate retaining (CR) total knee arthroplasty (TKA), and compare the iatrogenic injury of robotic-arm assisted (RA) TKA and conventional jig-based (CJ) TKA using it.

Methods

100 symptomatic knee osteoarthritis patients were chosen of which fifty received RA TKA, whereas fifty received CJ TKA. Posterior cruciate ligament (PCL), soft tissue envelope and bone resection surfaces were assessed during operation and scores allotted for each. The overall score was then graded to form the classification.

Results

The classification had a high inter-observer reliability. RA TKA patients had significantly better PCL scores, soft tissue injury scores, bony injury scores, and modified MASTI grades, and had decreased chances and extent of soft tissue release for coronal balancing. Lesser degree of constitutional varus and sagittal plane deformity, and lower BMI have been found to be associated with better soft tissue preservation and better-modified MASTI grades.

Conclusion

The 'modified MASTI classification' is a validated and reliable system to serve as a universal tool and platform for recording and grading iatrogenic bone and soft tissue injury during CR TKA. Using this classification, RA TKA is found to be less invasive and inflicts lesser extent of iatrogenic injuries when compared to CJ TKA. This classification can also be used as a parameter for evaluating the outcome of bone and soft tissue injuries and soft tissue releases to short- and long-term functional outcomes of patients, complications and longevity of implants.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43465-025-01343-3.

Identifying Sources of Error in Computer-Navigated Total Knee Arthroplasty Using Sensitivity Analyses in Knee Models

BACKGROUND

Long-term studies comparing computer-assisted total knee arthroplasty (TKA) to conventional techniques have not consistently demonstrated differences in outcomes. Errors may occur at various points of a navigated TKA, including surgeon variability in registering landmarks and when placing the cutting guide. The purpose of this study was to identify the sources of error during navigated TKA and to quantify their impact at each critical step of the procedure.

METHODS

Sawbones (n = 6) and three-dimensional-printed (n = 4) knee models were stabilized on a custom wooden platform. Landmarks were digitized with the navigation system, while a three-dimensional point capture system concurrently recorded identical points for precision assessment across multiple trials. Errors were quantified using transformation matrices (metric on SE(3)) to compare reference frames and resection planes. Sensitivity analyses using Monte Carlo simulations were performed to quantify the magnitude of specific errors in the navigation output.

RESULTS

The largest registration errors occurred at the hip center (8.2 ± 4.4 mm) and lateral tibial plateau (4.8 ± 3.7 mm), while the femur center exhibited the least variability (0.8 ± 0.5 mm). The metric on SE(3) analysis revealed that errors in femoral and tibial center landmarks significantly influenced bone reference frames. No clear correlation was found between bone reference frame errors and cut plane errors. Error clouds highlighted compact femoral errors (average 1.3 mm), but broader tibial errors (average 5.8 mm). Sensitivity analyses confirmed the femoral center as the most critical landmark for registration accuracy.

CONCLUSIONS

In computer-navigated TKA, landmarks closer to the knee joint demonstrated narrower safe zones and had the greatest impact on system accuracy. The lack of correlation between bone reference frame errors and cut plane errors suggests additional error sources. Improved intraoperative strategies, such as advanced imaging, refined algorithms, and enhanced training, are needed to optimize critical landmark registration and improve TKA outcomes.

Time to Achieve Minimal Clinically Important Difference (MCID) in Robotic Versus Manual Total Knee Arthroplasty: A Comparative Analysis

BACKGROUND

Robotics in arthroplasty remains controversial due to the uncertainty of clinical outcomes in robotic total knee arthroplasty (rTKA). This study aimed to compare the time to achieve the minimal clinically important difference (MCID) between rTKA and manual TKA (mTKA).

METHODS

A total of 726 TKAs (416 robotic and 310 manual) were analyzed. We conducted a retrospective analysis of 726 TKAs performed between 2019 and 2022. Patient-reported outcomes were assessed using the Patient-Reported Outcomes Measurement Information System (PROMIS) global physical, PROMIS physical function-10a (PF-10a), and Knee Injury and Osteoarthritis Outcome Score-physical function short-form (KOOS-PS) scores, both preoperatively and postoperatively. Survival curves, accounting for interval censoring, were utilized to evaluate the time to achieve MCID. Statistical comparisons between groups were made using log-rank and weighted log-rank tests.

RESULTS

Comparing time to achieve MCID without interval censoring, the median time for rTKA was significantly lower than mTKA for PROMIS global physical (3.5 versus 3.7 months, P = 0.032) and KOOS-PS (3.7 versus 5.3 months, P = 0.002) but similar for PROMIS PF-10a (6.0 versus 6.7 months, P = 0.16). Notably, interval censoring showed similar times to achieve MCID for rTKA and mTKA in PROMIS global physical (0.53 to 0.54 versus 1.23 to 1.24 months, P = 0.31), PROMIS PF-10a (3.03 to 3.03 versus 2.17 to 2.17 months, P = 0.89), and KOOS-PS (1.47 to 1.47 versus 2.17 to 2.17 months, P = 0.27).

CONCUSIONS

Using time to MCID methodology, the median time to achieve MCID did not differ by surgical technique. The present study offers valuable patient-centric insights into preoperative expectations management and patient education. Further prospective studies with more granular patient-reported outcomes measurement collection are needed to evaluate the true effectiveness of robotics in arthroplasty.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Is bicortical femoral pin insertion safe for image-based robotic knee arthroplasty surgery ? A comparative complications analysis in 970 consecutive cases

OBJECTIVES

Limited data exists on complications associated with robotic image-based system in knee arthroplasty. This study aims to document complications in robotic arm-assisted knee arthroplasties and evaluate the system's safety by comparing two femoral pin insertion methods: bicortical diaphyseal with additional stab wounds, and unicortical metaphyseal placement through the main incision.

METHODS

All patients undergoing primary knee arthroplasty with the image-based robotic system (Mako, Stryker, Mako Surgical Corp., Fort Lauderdale, FL, USA) from 1st March 2021 to 31st January 2024 with a minimum follow-up of 2 months were included. Demographics, system and non-system-related complications, as well as outcomes were recorded. Complications were categorized as either major (requiring a second surgical intervention) or minor.

RESULTS

A total of 970 consecutive cases (median age 69.3 years) were analyzed. The unicortical group comprised 651 cases, while the bicortical group 319. The incidence of non-system-related complications was 2.37%, with the most common being joint stiffness (10 cases; 1.03%), followed by lateral femoral condyle fracture (4; 0.41%). The overall incidence of system-specific complications was 1.03%. Pin-related femoral fractures occurred in 0.2% of cases, all postoperatively and in the unicortical group. There was no statistically significant difference between the femoral pin insertion-related complication rates among the two groups (0.3% in the unicortical, compared to 0% in the bicortical group; p-value ​= ​0.3). Complications included tibia fracture (0.1%), delayed wound healing (0.2%), superficial wound infection (0.1%), tibia osteomyelitis (0.1%), and "exostosis" (0.2%). The major complications rate was 0.3% and minor 0.7%.

CONCLUSIONS

Minimal system-specific overall complications indicate that robotic arm-assisted surgery is safe. The bicortical diaphyseal femoral pin insertion method does not increase the complication rates compared to the unicortical metaphyseal method.

LEVEL OF EVIDENCE

III.

Imageless Robotic Arm-Assisted Total Knee Arthroplasty: Workflow Optimization, Operative Times, and Learning Curve

Background Robotic arm-assisted total knee arthroplasty (RATKA) offers several advantages, including precise restoration of mechanical or kinematic alignment, accurate bone resections, reliable implant size prediction, alignment optimization, and dynamic gap balancing. However, a key concern among arthroplasty surgeons is the perceived increase in operative time associated with adopting this technology. This study describes the step-by-step surgical workflow of imageless RATKA and evaluates the surgical times and learning curve associated with this technique. Methods This study is a retrospective analysis of the data of the first 60 cases of imageless RATKA done between February 2023 and November 2024 at a single surgical center by the same surgical team. Patients undergoing imageless RATKA for Kellgren and Lawrence grade 4 osteoarthritis were included, while those with prior knee surgery or high tibial osteotomy were excluded. All procedures utilized the DePuy Attune implant with a tibia-first surgical workflow, performed via a midline vertical incision and medial parapatellar arthrotomy. Surgical times were recorded and analyzed by an independent observer not involved in the surgeries. The 60 cases were divided into four groups of 15 cases (group 1 consisted of the first 15 cases, i.e., case number 1 to case number 15; group 2 consisted of the next consecutive 15 cases, i.e., case number 16 to case number 30; group 3 consisted of case number 31 to case number 45; and group 4 consisted of the last 15 cases, i.e., case number 46 to case number 60) each to evaluate the learning curve and calculate mean surgical times. Results The surgical times (in minutes) of the various groups were as follows: group 1 (0-15 cases) = 96.27 ± 4.46; group 2 (16-30 cases) = 91.07 ± 3.75; group 3 (31-45 cases) = 88.67 ± 3.58; group 4 (46-60 cases) = 86.13 ± 3.66. Comparison of means shows p values of 0.005, 0.03, and 0.09 between group 1 and 2, group 2 and 3, and group 3 and 4, respectively, indicating normalization of the operative time and a learning curve of 15 cases.  Conclusion By following a standardized and reproducible tibia-first workflow, the operative time for imageless RATKA normalizes roughly after 15cases, i.e., group 2 onwards. This suggests that surgical time should not be a barrier for surgeons considering the adoption of this technology. The findings support the feasibility and efficiency of integrating robotic-assisted systems into routine arthroplasty practice.

A Comparison of 90-Day Complication Rates Between Intra- and Extra-incisional Pin Sites in Robotic Total Knee Arthroplasty

BACKGROUND

Robotic-assisted total knee arthroplasty (TKA) platforms require tibial and femoral pins to support rigidly fixed navigation arrays. These pins can be placed inside or outside the primary incision. We sought to compare 90-day complication rates between three different pin configurations: all-outside, intra-incisional femur/extra-incisional tibia, and all-inside.

METHODS

A retrospective cohort study of 2,880 patients undergoing robotic primary TKA was performed, including 1,004 patients (35%) with all-outside pins, 1,056 patients (37%) with intra-incisional femur/extra-incisional tibia pins, and 820 patients (29%) with all-inside pins. The primary outcomes were primary wound complications and pin-site wound complications within 90 days. Secondary outcomes were manipulations under anesthesia (MUAs) and complex regional pain syndrome (CRPS).

RESULTS

There were 41 (2.0%) tibial pin-site wound complications and three (0.3%) femoral pin-site wound complications. There were 109 (3.8%) wound complications involving the primary incision. There was no difference in primary wound complication rates between the all-outside, intra-incisional femur/extra-incisional tibia, and all-inside groups (3.3 versus 3.9 versus 4.3%, P = 0.54). There were 18 major wound complications requiring reoperation or readmission; 13 of these involved the primary incision only, three involved the primary incision and tibial pin sites, and two involved the tibial pin sites only. There were no differences between the three groups in the rates of MUAs (4.1 versus 2.4 versus 3.4%, P = 0.09) or CRPS (0.1 versus 0.1 versus 0.6%, P = 0.06), respectively. There were no intraoperative or postoperative periprosthetic pin-related fractures in the study sample.

CONCLUSIONS

Primary wound complication rates were similar in patients who had pins placed outside or within the primary incision during robotic TKA. However, among patients who had extra-incisional tibial pins, there was an additional 2.0% risk of tibial pin site-related wound complications. All-inside pin placement did not lead to an increased risk of CRPS or MUAs compared to extra-incisional tibial pins.

Current developments in robotic assistance technology for total knee arthroplasty: a comprehensive overview

Knee arthritis is a common degenerative joint disease, usually with joint swelling, chronic pain, and dysfunction as the main clinical manifestations. At present, the conservative treatment for knee arthritis is mostly using anti-inflammatory and analgesic drugs, but the effect is mostly temporary, and can not prevent its progress and surgery is usually the last treatment method. Total knee arthroplasty, also known as TKA, is one of the most effective treatments for osteoarthritis of the knee that has progressed to the end stage. The inevitable human factor in conventional total knee arthroplasty (TKA) frequently results in poor positioning of the prosthesis during the reconstruction of the lower limb's biomechanical axis. This can lead to severe postoperative pain, accelerated wear of the prosthesis, early loosening, and other problems in the affected knee, which has always been a primary concern for orthopaedic surgeons. Over the course of the past few years, China has gradually begun to develop joint robots. The idea is to plan the surgical plan based on the anatomical structure of the affected limb before the operation, and then to use a mechanical arm and a visual system to assist in the implantation of the prosthesis while the operation is being performed. The treatment costs of robot-assisted technology, on the other hand, vary greatly, and there is still a relatively small amount of high-quality evidence on clinical efficacy. This is because the field of robotic-assisted technology is a relatively new one that has gradually developed over the past few years. In order to provide a fundamental reference for the application value of new treatment methods for advanced knee osteoarthritis, it is necessary to conduct an analysis of the current status of the application of joint robots, as well as the technical advantages and disadvantages that they bring.This narrative study delineates the historical context and current clinical application of robots in knee replacement surgery. An examination of the advantages and disadvantages of RATKA in comparison to TKA offers insights on the prospective application value of the technology.Clinical trial number: Not applicable.

Navigating the Intersection of Technology and Surgical Education: Advancements, Challenges, and Ethical Considerations in Orthopedic Training

The emergence of technological advancements such as artificial intelligence, virtual reality, and robotics may offer new solutions to address crucial deficiencies in surgical residency training. However, these technologies also introduce ethical dilemmas and practical complexities. Achieving a balance between embracing innovation and refining traditional surgical techniques is essential in molding well-rounded, proficient surgeons. Addressing concerns such as disparities in access to technology and the risk of excessive automated system dependence demands thorough deliberation and the establishment of universal guidelines. By approaching these challenges with care and insight, surgeons can utilize new technology to elevate both surgical training and outcomes.

Dental implant placement accuracy with robotic surgery compared to free-hand, static and dynamic computer assisted techniques: Systematic review and meta-analysis

Background

This systematic review and meta-analysis compared the accuracy of robotic-assisted dental implant placement (r-CAIS) with conventional freehand, static computer-assisted (s-CAIS), and dynamic computer-assisted (d-CAIS) techniques.

Methods

A comprehensive search was conducted in PubMed, Google Scholar, Semantic Scholar, and the Cochrane Library from January 2000 to January 2024. Studies meeting PICOST criteria, including clinical and in vitro studies, were included. Data on coronal, apical, and angular deviations were extracted for meta-analysis. The risk of bias (RoB) was assessed using the QUIN RoB and JBI RoB tools.

Results

A total of 134 models and 100 patients with edentulous and partially edentulous arches were included. Eight studies (four in vitro, four in vivo) were reviewed, demonstrating that r-CAIS offers superior accuracy compared to freehand, s-CAIS, and d-CAIS techniques. Among the studies, two in vitro and two in vivo studies had a low RoB, while others had a high RoB. The meta-analysis of five studies showed significant improvements in coronal, apical, and angular deviations with robotic systems.

Conclusion

Robotic-assisted systems showed greater accuracy than traditional non-robotic systems. However, this finding should be interpreted with caution due to the limited number of clinical studies and potential funding biases. Moreover, the high cost of robotic systems presents challenges for routine clinical implementation. Future research should focus on cost-effectiveness and seek broader clinical validation.

[Digital tools in primary total knee arthroplasty-Prevalence in the German-speaking region]

BACKGROUND

Digital tools are being increasingly used worldwide in primary knee arthroplasty. This study aimed to analyze the utilization density of digital tools, the preferred alignment strategies, and the obstacles and benefits of implementing these technologies in German-speaking countries.

MATERIALS AND METHODS

An online survey with 57 questions about digital tools in primary knee arthroplasty and their usage was conducted among members of the Arthroplasty Working Group (AE). The survey included questions on navigation, robotics, patient-specific instruments, individualized implants, and augmented reality.

RESULTS

The survey revealed that 18% of hospitals use navigation and 17% use robotic systems in primary total knee arthroplasty surgery. The main reasons for not implementing supportive technologies were high acquisition and ongoing costs, as well as longer surgical duration. Patient-specific instruments and individualized implants currently play a minor role. Patient-specific alignment strategies, such as kinematic (navigation: 35%; robotics: 44%) and functional alignment (navigation: 15%; robotics: 35%), are preferred in this context. With conventional instrumentation predominantly mechanical alignment was applied (79%).

DISCUSSION

The results indicate a relatively high utilization density of digital tools, which are mainly used to perform personalized alignment strategies in primary knee arthroplasty in German-speaking countries. This was particularly evident in high-volume hospitals. Economic aspects were the main reasons for not using these technologies. Future developments should aim to simplify the systems and thus achieve improved cost efficiency.

Accuracy of a New Augmented Reality Assisted Technique for Total Knee Arthroplasty: An In Vivo Study

Background

Total knee arthroplasty (TKA) remains the standard of care for treating end-stage osteoarthritis of the knee. Approximately 15%-20% of the patients are dissatisfied following surgery. To improve accuracy and outcomes of TKA, various assistive technologies have been introduced. For this study, an augmented reality (AR) system was explored and tested.

Methods

The Knee + system (Pixee Medical, Besancon, France) was used to guide TKA. It uses a combination of quick response-code labeled instruments and AR glasses to guide tibial and femoral cuts. The primary research goal was to evaluate its accuracy by direct comparing the planned angular values for lateral distal femoral angle, medial proximal tibial angle, hip-knee-ankle axis, and tibial slope to the intraoperative obtained values and the measured angles on postoperative full leg radiographs. The secondary research goal was to assess its feasibility.

Results

This retrospective study evaluated 124 patients, with a follow-up of at least 1 year. The average absolute difference between planned and measured postop values were 1.39° for lateral distal femoral angle, 1.03° for medial proximal tibial angle, 2.16° for tibial slope, and 1.51° for hip-knee-ankle axis. Within the follow-up period, 8 complications were observed. The average surgical time was 83 minutes.

Conclusions

This study has demonstrated a high accuracy, comparable to robotic-assisted total knee arthroplasty, of the Knee + AR system. It has shown to be a safe, cheap and time-efficient assistive technology for patients undergoing medial pivot TKA.

Trends and epidemiology in robotic-assisted total knee arthroplasty: Reduced complications and shorter hospital stays

INTRODUCTION

This study provides an in-depth analysis of the immediate postoperative outcomes and implications or robotic-assisted total knee arthroplasty (RA-TKA) compared with conventional TKA (C-TKA), particularly with regard to mortality, complications, hospital stay and costs, drawing from a comprehensive nationwide data set.

METHODS

The Nationwide Inpatient Sample (NIS) database, the largest all-payer inpatient healthcare database in the United States, was used to identify all patients who underwent RA-TKA or C-TKA from 2016 to 2019. A total of 527,376 cases, representing 2,638,679 patients who underwent elective TKA were identified, of which 88,415 had RA-TKA. To mitigate potential variations and selection bias in baseline characteristics between the two groups, a propensity score-matched analysis was employed to further balance and refine our data set, resulting in 176,830 patients evenly distributed between the groups. Analysis was performed according to demographics, immediate post-operative complications, and economic data, including payor class, length of stay and total charges.

RESULTS

There was a marked shift towards RA-TKA, from an initial 0.70% in 2016 to a notable 7.30% by 2019. Patients who underwent RA-TKA were slightly younger (66.2 ± SD years), compared to the C-TKA group (66.7 ± SD years). Hospital stay was 1.89 days and 2.29 days for RA-TKA and C-TKA, respectively. Charges metrics revealed slightly higher charges for RA-TKA. Less postoperative complications were found in the RA-TKA group, such as blood loss, anaemia, acute kidney injury, venous thromboembolism, pulmonary embolism, pneumonia and surgical wound complication. Even following the propensity score matching, these findings remained consistent and statistically significant.

CONCLUSIONS

RA-TKA use in the United States has grown substantially in the last few years and has been associated with significantly reduced immediate post-operative complications and length of hospital stay compared to C-TKA, offering safer surgical management for TKA patients. Further studies on the short- and long-term outcomes of RA-TKA would improve the understanding of the full potential of this technology.

LEVELS OF EVIDENCE

Level III.

Effectiveness of Periarticular Pin Tracker Placement Through a Single Main Incision in Robotic-Assisted Total Knee Arthroplasty: Technical Note and Short-Term Results

Background and Objectives: Robotic-assisted total knee arthroplasty (TKA) is gaining popularity worldwide, leading to a potential increase in the number of pin tracker-related complications. This study determined the effectiveness of periarticular pin tracker placement in the distal femur and proximal tibia through a single main incision during robotic-assisted TKA over a minimum follow-up period of 6 months. Materials and Methods: A consecutive series of 149 TKAs was performed in 108 patients using the triathlon posterior-stabilized total knee prosthesis with a robotic-assisted system at our hospital from December 2023 to February 2024. Clinical outcomes and complications associated with pin tracker sites, including pin-site infection, neurovascular injury, hematoma, soft-tissue morbidity, and pin-site fracture, were assessed. Results: The mean Knee Society knee score improved from 42.5 preoperatively to 76.3 points at the final follow-up, whereas the mean Knee Society function score improved from 43.1 preoperatively to 78.1 points at the final follow-up (both p < 0.05). No patient experienced any minor or major complications related to the use of pin trackers in the distal femur and proximal tibia. Conclusions: This periarticular technique that uses pin trackers in the distal femur and proximal tibia through a single main incision could be a useful option for orthopedic surgeons while performing robotic-assisted TKA.

Are all robotic technologies created equal? Comparing one of the latest image-free robotic technologies to all other robotic systems for total knee arthroplasty

BACKGROUND

Robotic-assisted technologies have been developed to increase surgical precision and reduce surgical variability in total knee arthroplasty (TKA). Several different robotic systems have been introduced in the last decade for TKA. The DePuy Synthes VELYS™ Robotic-Assisted Solution (VRAS) is an imageless system designed to eliminate the need for preoperative CT scans and is one of the latest entrants in the rapidly evolving field of robotic technology in TKA. This study compared the clinical and economic outcomes associated with VRAS and other robotic-assisted technologies for primary TKA.

METHODS

A retrospective cohort study using the Premier Healthcare Database included patients who underwent primary TKA with VRAS or other robotic-assisted technologies from January 1, 2022, to April 30, 2023. The primary outcome for the study was hospital follow-up visits (revisits) within 90 days post-TKA. Secondary outcomes included readmission and revision rates within 90 days post-TKA, operating room time, length of stay, discharge status and hospital costs. Cohorts were balanced using propensity score fine stratification, and generalized linear models were constructed to evaluate outcomes.

RESULTS

This study included 827 VRAS TKA patients and 16,428 TKA patients treated with other robotic-assisted technologies. The 90-day all-cause and knee-related revisit rates were significantly lower for VRAS than for other robotic-assisted technologies (all-cause 13.9% vs. 22.8% and knee-related 2.8% vs. 5.4%, respectively; p value < 0.01). The all-cause and knee-related 90-day readmission rates were also lower for VRAS, although the differences were not statistically significant. The 90-day revision rates were similar for VRAS and other robotic-assisted technologies (0.48% vs. 0.45%), as was the operating room time (138 vs. 137 min). The 90-day knee-related cost for the VRAS cohort was $15,048 compared to $16,867 for other robotic technologies.

CONCLUSIONS

This database study demonstrated that early postoperative revisit rates and total cost of care are lower for VRAS than for all other robotic-assisted technologies for TKA, while operating room time and discharge status were similar. These are important findings in ever-evolving healthcare systems that are increasingly cost conscious and cognizant of principles associated with value-based care.

Enhanced recovery after surgery day surgery for MAKO® robotic-arm assisted TKA; better outcome for patients, improved efficiency for hospitals

Introduction

Robotic-assisted Total Knee Arthroplasty (TKA) was designed to improve implant position accuracy by providing surgeons with real-time intra-operative data to tailor the operation to the patient. Proponents of robotic-assisted TKA believe that this translates into meaningful improvements in outcomes. However, there are concerns that the longer surgical duration associated with robotic-assisted TKA leads to longer length of stay (LOS). In this study, the authors investigated the outcome of MAKO® Robotic-arm Assisted TKA combined with ERAS protocol to assess its effect on LOS and short-term outcomes.

Methods

All patients who had undergone unilateral MAKO® ERAS Day Surgery TKA from August 2020 to July 2021 were prospectively followed up and matched to patients who underwent conventional ERAS Day Surgery TKA in the same time period. Factors such as surgical duration, LOS, immediate reduction in pain, 30-days complications, and 6-month PROMs and knee ROM were compared between the two groups.

Results

42 patients underwent MAKO® ERAS Day surgery TKA and were matched to 42 patients who underwent conventional ERAS Day surgery TKA. The study found that despite the longer surgical duration, LOS was comparable between both groups (1.1 ± 0.9days in the MAKO® group vs 1.0 ± 0.3days in the conventional group, p = 0.755) with successful 24-hour discharge in 88.1 % of patients in the MAKO® group. The MAKO® group achieved significantly better ROM compared to the conventional group 6-months post operatively. Post-operative PROMs were comparable between both groups.

Conclusion

ERAS Day Surgery protocol can significantly reduce the LOS of patient undergoing MAKO® Robotic-arm Assisted TKA, conferring cost savings and making it a valid option for patients.

Efficacy and Safety of Bone Wax Application at Different Time Points to Reduce Postoperative Blood Loss in Total Knee Arthroplasty: A Prospective Randomized Controlled Trial

OBJECTIVE

In addition to the surface hemorrhage of cancellous bone after large-area osteotomy, the intramedullary hemorrhage after the reamed knee joint is also a major cause of postoperative bleeding after total knee arthroplasty (TKA). This study evaluated the efficacy and safety of bone wax application at different time points of prone hemorrhage to reduce perioperative blood loss.

METHODS

From August 2023 to December 2023, 150 patients undergoing primary unilateral TKA were included in this prospective, randomized controlled trial, patients were randomly divided into three groups: group A, after autogenous osteotomy plug was used to fill the femoral medullary cavity, the residual space was sealed with bone wax and the exposed cancellous bone surface around the prosthesis was coated with bone wax after the prosthesis adhesion; group B, only the exposed cancellous bone surface around the prosthesis was coated with bone wax; and group C, no bone wax was used. The primary outcome was total perioperative blood loss. Secondary outcomes included occult blood loss, postoperative hemoglobin reduction, blood transfusion rate, lower limb diameter, and knee function, while length of hospital stay was recorded. Tertiary outcomes included the incidence of postoperative related adverse events.

RESULTS

The total blood loss in group A (551.5 ± 224.5 mL) and group B (656.3 ± 267.7 mL) was significantly lower than that in group C (755.3 ± 248.3 ml, p < 0.001), and the total blood loss in group A was also lower than that in group B (p < 0.05). There were also significant differences in the reduction of hemoglobin level and hidden blood loss among the three groups (p < 0.05). However, there was no significant improvement in postoperative lower limb swelling, knee joint activity and hospitalization time; there was no significant difference in the incidence of complications such as thromboembolism.

CONCLUSION

The use of bone wax in TKA can safely and effectively reduce perioperative blood loss and hemoglobin drop rate, and multiple use at time points during the operation when blood loss is prone to occur can produce more significant hemostatic effect.

Surgical Technique for Complementing Robotic-Assisted Total Knee Arthroplasty in Middle-Aged Patients with Rigid Knee Bones

This study reports 12 cases of inaccurate bone cutting from a single-surgeon series of 509 consecutively performed robotic-assisted total knee arthroplasty (TKA) for 1 year. In addition, a complementary technique with the combined benefits of robotic-assisted and manual techniques that address this issue is described. From June 2020 to May 2021, a consecutive series of 509 TKAs was performed on 338 patients using a posterior-stabilized total knee prosthesis with a robotic-assisted system at our hospital. The surgical records were reviewed to identify the causative bone locations and bone re-cutting events correlated with improper trial instrument positioning. The re-cutting rate was 2.4% (12/509). All re-cutting attempts occurred because of improper cutting of the femoral posterior chamfer. Re-cutting was attempted mostly on middle-aged male patients. This complementary technique can facilitate manual bone cutting while retaining the advantages of robotic surgery during robotic-assisted TKA. Additionally, the combined technique of manual bone cutting and robotic-assisted surgery can be a useful alternative for middle-aged male patients with rigid knee bones.

Functional Outcome in Obese Patients Undergoing Image-Based Cruciate Retaining Robotic-Assisted Total Knee Arthroplasty Using the Subvastus Approach: A Short-Term Study

Introduction Knee osteoarthritis (OA) is a prevalent degenerative joint disease that significantly affects quality of life, especially among obese and morbidly obese individuals. Total knee arthroplasty (TKA) is an effective treatment for end-stage OA, but it presents unique challenges in obese patients. The mini-subvastus approach (SA) and robotic-assisted TKA (RA-TKA) are emerging techniques that may address these challenges. This study evaluates the clinical and radiological outcomes of cruciate-retaining (CR) RA-TKA using the mini-subvastus approach in obese and morbidly obese patients. Methods This study included 114 obese patients (215 knees) with primary OA who underwent CR RA-TKA (Maxx Meril CR knee, USA) using the Cuvis Joint® robotic system. Patients had a BMI of ≥30 kg/m² (n=101) and morbid obesity with a BMI ≥40 kg/m² (n=13). Preoperative planning involved CT scans and the J-planner for optimal implant size and positioning. Surgery was performed without tourniquets, and patients were mobilized postoperatively. Clinical outcomes were assessed using visual analog scale (VAS) scores and the American Knee Society Score (AKSS) at three and six months. Results The study included 85 females and 29 males with an average age of 61.8 years. Satisfactory knee exposure was achieved in all cases using SA, with no major complications such as wound infections, deep vein thrombosis, or component misalignment. Intraoperative challenges were managed effectively, including two cases of medial collateral ligament avulsion and one partial patellar tendon avulsion. Postoperative VAS scores showed significant pain reduction from pre-op (6.54) to post-op day 3 (1.3). AKSS improved from a pre-op average of 33.9 to 70.7 at three months and 80.9 at six months. Most patients (80%) achieved exceptional range of motion (ROM) ≥120° at six months. Discussion The mini-subvastus approach in RA-TKA offers several advantages, including reduced postoperative pain, faster recovery, and improved quadriceps strength, even in obese patients. The use of robotic assistance ensures accurate component positioning and alignment, mitigating the challenges typically associated with obese patients undergoing TKA. Conclusion The study demonstrates the feasibility and effectiveness of CR RA-TKA using the mini-subvastus approach in obese and morbidly obese patients. This technique provides adequate exposure, reduces pain, and promotes early mobilization and recovery with satisfactory clinical and radiological outcomes. The findings support the potential for wider adoption of this approach in managing knee OA in obese populations, though further studies with longer follow-up are warranted.

Herpes Zoster Risk After Total Knee Replacement: a multicenter, propensity-score-matched cohort study in the United States

Background: Total knee replacement (TKR) is a common surgical procedure for osteoarthritis (OA) patients. TKR may increase susceptibility to herpes zoster (HZ) by inducing immunosuppression, surgical stress, and nerve injury. However, limited data exist on the relationship between TKR and HZ. This study examined the risk of HZ over time among OA patients who underwent TKR and those who did not, using a large population-based cohort. Method: Utilizing the TriNetX research network, people with OA and underwent TKR were recruited as case group. After 1:1 propensity score matching, OA patients who never experienced TKR were included as control group. Covariates, including demographics, comorbidities, and laboratory data, were balanced using propensity score matching. A 5-year follow-up assessed the hazard ratio of incident HZ and related complications. Results: Compared to the control group, a significantly elevated risk of HZ was observed in the TKR cohort across 5-year follow-up period, with the hazard ratio of 1.223 (95% CI: 1.089-1.373). Zoster without complications presented 1.173-fold risk in TKR patients while comparing with non-TKR controls. However, most other secondary outcomes related to HZ complications-such as encephalitis, neurological involvement, ocular disease, and disseminated zoster-did not show a significant increase in risk. The risk of HZ was statistically significant for females and older adults in the TKR cohort than in the control cohort. Conclusions: OA patients who underwent TKR had an increased risk of HZ compared to those who did not receive the procedure, especially females and older adults. These findings highlight the need for HZ monitoring/prevention protocols and further research on mitigating viral reactivation after major joint surgery.

Early and delayed periprosthetic joint infection in robot-assisted total knee arthroplasty: a multicenter study

BACKGROUND

Robot-assisted total knee arthroplasty (RA-TKA) has significantly improved knee surgery outcomes in the last few years. However, its association with the periprosthetic joint infection (PJI) rate remains debatable. This study investigates the incidence of early and delayed PJI in a multicentric cohort of patients who underwent RA-TKA, aiming to elucidate the risk associated with this procedure.

METHODS

This retrospective study analyzed data from a consecutive series of patients who underwent RA-TKA using the NAVIO Surgical System (Smith & Nephew, Memphis, USA) between 2020 and 2023. The inclusion criteria encompassed individuals over 18 years of age with a minimum follow-up period of three months. The primary outcome was the incidence of early and delayed PJI, defined according to the European Bone and Joint Infection Society (EBJIS) diagnostic criteria. Secondary outcomes included the evaluation of postoperative complications.

RESULTS

The study included patients who underwent RA-TKA with the NAVIO system, achieving an average follow-up of 9.1 ± 3.9 months. None of the patients met the EBJIS criteria for a likely or confirmed infection, indicating an absence of both early and delayed PJI cases. Two patients required subsequent surgical interventions due to patellar maltracking and prosthetic loosening, respectively. Additionally, three patients underwent passive manipulation under anesthesia (MUA).

CONCLUSION

The findings indicate no evidence of early or delayed PJI in patients undergoing RA-TKA within the study period. The low complication rate further supports the reliability and safety of this surgical technique in short-term follow-up.

LEVEL OF EVIDENCE

IV.

Correlation Between Planned and Executed Bone Cuts Using Robotics in Total Knee Arthroplasty: A Prospective Study of 500 Patients

Objective

This study evaluated the precision of robotic-arm-assisted total knee arthroplasty (RATKA) in performing bone resection, predicting component size, managing soft tissue tension, and determining postoperative range of motion (ROM).

Methods

A total of 500 participants were enrolled in this prospective cohort research. The procedures were conducted at a single facility, with a uniform method and implant design. The Cuvis system, a fully automated robot, was utilized for the study. The precise removal of bone at both the tibial and femur sites, the positioning of the implant, and the release of soft tissue were documented and then compared to the preoperative plan.

Results

The distal (medial and lateral) femoral cuts had a mean absolute deviation from the plan of 0.23 mm, while the posterior (medial and lateral) femoral cuts had a mean absolute difference of 1 mm and 1.4 mm, respectively. The absolute discrepancies in the medial and lateral tibial cuts are 0.93 mm and - 0.06 mm, respectively. Out of 1000 bone resections, 980 (98%) were within < 1 mm from the preoperative plan. The predictions for the sizes of the tibial and femoral components had accuracies of 100% and 98.9%, respectively.

Conclusion

These findings collectively underscore the effectiveness of the fully automated Cuvis robotic system in achieving consistent and accurate results in bone resections and implant sizing, highlighting its potential as a valuable tool in orthopedic surgery.

Comparison of robotic-assisted total knee arthroplasty: an updated systematic review and meta-analysis

This study was conducted to compare the changes in different clinical scores and imaging indexes of patients who underwent robot-assisted total knee arthroplasty (RA-TKA) and manual total knee arthroplasty (M-TKA). PubMed, Web of Science, Cochrane Library and Embase were searched according to PRISMA guidelines in June 2024. Search terms included "robot-assisted", "manual" and "total knee arthroplasty". Outcome indicators included American Knee Society Score (KSS), Western Ontario McMaster Universities Osteoarthritis Index (WOMAC), Oxford Knee Score (OKS), range of motion (ROM), Hospital for Special Surgery (HSS) score, Forgotten Joint Score (FJS), 36-Item Short Form Health Survey (SF-36), operation duration (min), intraoperative blood loss (ml), pain score, patient's satisfaction scores, hip-knee-ankle (HKA) angle, frontal femoral component angle, frontal tibia component angle, lateral femoral component angle and lateral tibia component angle. A total of 1,033 articles were obtained after removing duplicates, and 12 studies involving 2,863 patients (1,449 RA-TKAs and 1,414 M-TKAs) were finally meta-analyzed (22-32). The baseline data of both groups were similar in all results. Meta-analysis suggested a better performance of the RA-TKA group than the M-TKA group regarding the HKA angle. The manual TKA reduced the operation time and significantly improved the range of motion. The results of > 6 months follow-up showed that M-TKA was better than RA-TKA in terms of KSS score and WOMAC. Compared with M-TKA, RA-TKA can produce more accurate prosthetic alignment, but it does not lead to better clinical results. Orthopedic surgeons should choose between two surgical procedures according to their own experience and patients' characteristics.

Robotic assisted Total Knee Arthroplasty (TKA) is not associated with increased patient satisfaction: a systematic review and meta-analysis

PURPOSE

Total knee arthroplasty (TKA) is a common orthopedic surgery, yet postoperative dissatisfaction persists in around 20% of cases. Robotic total knee arthroplasty (rTKA) promises enhanced precision, but its impact on patient satisfaction compared to conventional TKA remains controversial (cTKA). This systematic review aims to evaluate patient satisfaction post-rTKA and compare outcomes with cTKA.

METHODS

Papers from the following databases were identified and reviewed: PubMed, Scopus, Web of Science, and the Cochrane Online Library, using keywords like "Knee replacement," "Total knee arthroplasty," "Robotic," and "Patient satisfaction." Extracted data included patient satisfaction measures, Knee Society Score, Oxford Knee Score, Forgotten Joint Score, SF-36, HSS, and KOOS. Statistical analysis, including odds ratio and 95% CI was performed using R software. Heterogeneity was assessed using Cochrane's Q test.

RESULTS

The systematic review included 17 articles, involving 1148 patients (571 in the rTKA group and 577 in the cTKA group) assessing patient satisfaction following rTKA. An analysis of proportions reveals rTKA satisfaction rate was 95%, while for cTKA, it was 91%. A meta-analysis comparing rTKA and cTKA found no statistically significant difference in patient satisfaction. Additionally, various patient-reported outcome measures (PROMs) were examined, showing mixed results across different studies and follow-up periods.

CONCLUSIONS

The results of this study found no difference in patient satisfaction outcomes in the short to mid-term for rTKA compared to conventional methods. This study does not assert superiority for the robotic approach, highlighting the need for careful consideration of various factors influencing outcomes in knee arthroplasty.

Robots on the Stage: A Snapshot of the American Robotic Total Knee Arthroplasty Market

» Computer-assisted robots aid orthopaedic surgeons in implant positioning and bony resection. Surgeons selecting a robot for their practice are faced with numerous options. This study aims to make the choice less daunting by reviewing the most commonly used Food and Drug Administration-approved robotic total knee arthroplasty platforms in the American arthroplasty market.» Modern total knee arthroplasty (TKA) robots use computer guidance to create a virtual knee model that serves as the surgeon's canvas for resection planning.» Most available robotic TKA (rTKA) systems are closed semiactive systems that restrict implant use to those of the manufacturer.» Each system has distinct imaging requirements, safety features, resection methods, and operating room footprints that will affect a surgeon's technique and practice.» Robots carry different purchase, maintenance, and equipment costs that will influence patient access across different socioeconomic groups.» Some studies show improved early patient-reported outcomes with rTKA, but long-term studies have yet to show clinical superiority over manual TKA.

Total Knee Arthroplasty With Robotic and Augmented Reality Guidance: A Hierarchical Task Analysis

Background

Total knee arthroplasty (TKA) is a commonly performed procedure that has traditionally utilized reproducible steps using a set of mechanical instruments. The number of TKAs performed using robotic assistance is increasing, and augmented reality (AR) navigation systems are being developed. Hierarchical task analysis (HTA) aims to describe the steps of a specific task in detail to reduce errors and ensure reproducibility. The objective of this study was to develop and validate HTAs for conventional, robotic-assisted, and AR-navigated TKA.

Methods

The development of HTAs for conventional TKA involved an iterative review process that incorporated the input of 4 experienced arthroplasty surgeons. The HTAs were then adapted for robotic-assisted and AR-navigated TKA by incorporating specific steps associated with the use of these systems. The accuracy and completeness of the HTAs were validated by observing 10 conventional and 10 robotic-assisted TKA procedures.

Results

HTAs for conventional, robotic-assisted, and AR-navigated TKA were developed and validated. The resulting HTAs provide a comprehensive and standardized plan for each procedure and can aid in the identification of potential areas of inefficiency and risk. Robotic-assisted and AR-navigated approaches require additional steps, and there are an increased number of instances where complications may occur.

Conclusions

The HTAs developed in this study can provide valuable insights into the potential pitfalls of robotic-assisted and AR-navigated TKA procedures. As AR-navigation systems are developed, they should be optimized by critical analysis using the developed HTAs to ensure maximum efficiency, reliability, accessibility, reduction of human error, and costs.

Robotic Total Knee Arthroplasty: An Update

Total knee arthroplasty (TKA) is a gold standard surgical procedure to improve pain and restore function in patients affected by moderate-to-severe severe gonarthrosis refractory to conservative treatments. Indeed, millions of these procedures are conducted yearly worldwide, with their number expected to increase in an ageing and more demanding population. Despite the progress that has been made in optimizing surgical techniques, prosthetic designs, and durability, up to 20% of patients are dissatisfied by the procedure or still report knee pain. From this perspective, the introduction of robotic TKA (R-TKA) in the late 1990s represented a valuable instrument in performing more accurate bone cuts and improving clinical outcomes. On the other hand, prolonged operative time, increased complications, and high costs of the devices slow down the diffusion of R-TKA. The advent of newer technological devices, including those using navigation systems, has made robotic surgery in the operatory room more common since the last decade. At present, many different robots are available, representing promising solutions to avoid persistent knee pain after TKA. We hereby describe their functionality, analyze potential benefits, and hint at future perspectives in this promising field.

Outcomes following robotic assisted total knee arthroplasty compared to conventional total knee arthroplasty

INTRODUCTION

This study elaborates on previous research to compare length of stay, complication rates, and total cost between patients undergoing robotic assisted total knee arthroplasty (rTKA) and conventional total knee arthroplasty (cTKA). We hypothesized that patients undergoing rTKA would have reduced length of stay, lower complication rates, improved perioperative outcomes, and higher total healthcare costs than those undergoing cTKA.

METHODS

Data were collected from the National Inpatient Sample Database Healthcare Cost and Utilization Project between the years 2016-2019. Patients undergoing rTKA and cTKA were identified under International Classification of Diseases, 10th revision codes (ICD-10-CM/PCS). Length of stay, specific complications, and total costs were examined at time point. SPSS (v 27.0 8, IBM Corp. Armonk, NY) was utilized to compare demographic and analytical statistics between rTKA and cTKA. rTKA and cTKA were compared both before and after propensity matching.

RESULTS

17,249 rTKA (3.09%) and 541,122 cTKA (96.91%) were included. Compared to cTKA patients, rTKA patients had reduced average length of stay of 1.91 days (p < 0.001), higher average total cost of $67133.34 (p < 0.001), reduced periprosthetic infection (OR = 0.027, p < 0.001), periprosthetic dislocation (OR = 0.117, p < 0.001), periprosthetic mechanical complication (OR = 0.315, p < 0.001), pulmonary embolism (OR = 0.358, p < 0.001), transfusion (OR = 0.366, p < 0.001), pneumonia (OR = 0.468, p = 0.002), deep vein thrombosis (OR = 0.479, p = 0.001), and blood loss anemia (OR = 0.728, p < 0.001). These differences remained statistically significant even after propensity matching.

CONCLUSIONS

This study supports our hypothesis that rTKA is associated with fewer complications, but higher average total cost than cTKA. Our study shows that rTKA can be safely performed in older and sicker patients. Future studies assessing the impacts of these findings on patient reported outcomes would provide further insight into the benefits of rTKA. Furthermore, identifying patient specific factors that place them at risk for increased complications with cTKA as opposed to rTKA could provide surgeons insight on the method of TKA that maximizes patient outcomes while minimizing healthcare cost.

Osteoporosis, Osteoarthritis, and Subchondral Insufficiency Fracture: Recent Insights

The increased incidence of osteoarthritis (OA), particularly knee and hip OA, and osteoporosis (OP), owing to population aging, have escalated the medical expense burden. Osteoarthritis is more prevalent in older women, and the involvement of subchondral bone fragility spotlights its association with OP. Notably, subchondral insufficiency fracture (SIF) may represent a more pronounced condition of OA pathophysiology. This review summarizes the relationship between OA and OP, incorporating recent insights into SIF. Progressive SIF leads to joint collapse and secondary OA and is associated with OP. Furthermore, the thinning and fragility of subchondral bone in early-stage OA suggest that SIF may be a subtype of OA (osteoporosis-related OA, OPOA) characterized by significant subchondral bone damage. The high bone mineral density observed in OA may be overestimated due to osteophytes and sclerosis and can potentially contribute to OPOA. The incidence of OPOA is expected to increase along with population aging. Therefore, prioritizing OP screening, early interventions for patients with early-stage OA, and fracture prevention measures such as rehabilitation, fracture liaison services, nutritional management, and medication guidance are essential.

Navigating the Divide: A Comprehensive Review of the Mechanical and Anatomical Axis Approaches in Total Knee Replacement

This comprehensive review explores the mechanical and anatomical axis approaches in total knee replacement (TKR) surgery, addressing the ongoing debate within the orthopedic community. Emphasizing the significance of TKR in alleviating knee-related disorders, this review underscores the pivotal role of accurate alignment in achieving optimal surgical outcomes. The purpose is to navigate the divide between the well-established mechanical axis approach, focusing on a straight-line alignment, and the anatomical axis approach, aligning with natural knee landmarks. The analysis delves into the advantages, disadvantages, and clinical implications of each approach, offering a nuanced perspective on their efficacy. The conclusion emphasizes a patient-centric approach, recommending the adoption of hybrid strategies and the incorporation of emerging technologies for enhanced precision. The future of TKR aligns with personalized medicine, leveraging advancements in computer-assisted navigation, robotics, and patient-specific implants. Ongoing professional development and interdisciplinary collaboration are crucial for surgeons, and as the field evolves, innovations in artificial intelligence, imaging, and 3D printing are expected to shape the trajectory of TKR alignment approaches.

Functional alignment maximises advantages of robotic arm-assisted total knee arthroplasty with better patient-reported outcomes compared to mechanical alignment

PURPOSE

Robotic arm-assisted total knee arthroplasty (RTKA) enables adjustment of implant position to achieve the surgeon's preferred alignment. However, the alignment concept that most effectively enhances patient satisfaction remains unclear. This study compares the clinical outcomes of patients who underwent functionally aligned RTKA (FA-RTKA), mechanically aligned conventional TKA (MA-CTKA) and mechanically aligned RTKA (MA-RTKA).

METHODS

A prospectively collected database was retrospectively reviewed for patients who underwent primary TKA for knee osteoarthritis. One hundred and forty-seven knees were performed with MA-CTKA, followed by 72 consecutive knees performed with MA-RTKA, and subsequently, 70 consecutive knees performed with FA-RTKA were enrolled. After 1:1 propensity score matching of patient demographics, 70 knees were finally included in each group. The extent of additional soft tissue release during surgery was identified, and the Coronal Plane Alignment of the Knee classification was utilised to categorise the alignment. At the 1-year follow-up, patient-reported outcomes, including the pain Visual Analogue Scale, Knee Society Score, Western Ontario and McMaster Universities Arthritis Index and Forgotten Joint Score-12, were also compared among the groups.

RESULTS

The FA-RTKA group showed significantly less additional soft tissue release than the MA-CTKA and MA-RTKA groups (15.7%, 38.6% and 35.7%, respectively; p = 0.006). Statistically significant differences in functional scores were observed in the postoperative 1-year clinical outcomes in favour of the FA-RTKA group, which had a significantly larger percentage of knees that maintained constitutional alignment and joint line obliquity than those of the other groups.

CONCLUSIONS

Functionally aligned TKA showed superior 1-year postoperative patient-reported outcomes compared with those of conventional and robotic arm-assisted mechanically aligned TKA. Therefore, the advantage of RTKA is maximised when the implant positioning is based on functional alignment. The application of RTKA with mechanical alignment has been proven ineffective in improving the clinical outcomes of patients.

LEVEL OF EVIDENCE

Level III.

Robotic-assisted total knee arthroplasty is not associated with improved accuracy in implant position and alignment compared to conventional instrumentation in the execution of a preoperative digital plan

Purpose

The primary objective of the present study was to evaluate if robotic-assisted total knee arthroplasty (RO-TKA) results in improved accuracy compared to conventional TKA (CO-TKA) with respect to alignment and component positioning executing a preoperative digital plan. The secondary objective was to compare patient-reported outcome measures (PROMs) between the two groups at 6 months of follow-up (FU).

Methods

Patients who underwent primary TKA using the concept of constitutional alignment were identified from the database. Each patient underwent preoperative digital planning as well as postoperative evaluation of the preoperative plan (alignment and component position) using mediCAD® software (Hectec GmbH). Two groups were formed: (i) The RO-TKA group (n = 30) consisted of patients who underwent TKA with a robotic surgical system (ROSA®, Zimmer Biomet) and (ii) the CO-TKA group (n = 67) consisted of patients who underwent TKA with conventional instrumentation. To assess accuracy, all qualitative variables were analysed using the χ 2 test. Tegner activity scale, Oxford Knee Score and visual analogue scale were assessed preop and at 6-month FU. To assess differences between the two groups, a 2 × 2 repeated measures analysis of variance was performed.

Results

There was no significant (p > 0.05) difference in the accuracy of alignment as well as tibial and femoral component position between the two groups. At the 6-month FU, there was no significant (p > 0.05) difference in PROMs between the two groups.

Conclusion

While robotic TKA may have some potential advantages, no significant difference was found between robotic and conventional TKA with respect to limb alignment, clinical outcomes and component positioning.

Level of Evidence

Level III.

The wear and kinematics of two medially stabilised total knee replacement systems

BACKGROUND

Medially stabilised total knee replacement systems aim to provide a more natural feeling knee replacement by providing increased stability through flexion. The aim of this study was to compare the kinematics and wear of two different medially stabilised total knee replacement systems in an experimental simulation study. The Medial Rotation Knee™ system (MRK) is an early medially stabilised knee (>20 years clinical success); the SAIPH® knee system being a more modern and refined, bone conserving evolution of the original design with a larger size range.

METHODS

Three SAIPH and three MRK total knee replacements (MatOrtho Ltd, UK) were investigated. The study was performed on a knee simulator with load controlled input kinematic conditions (ISO 14243-1). 6 million cycles of simulation were carried out with the wear of the UHMWPE tibial components assessed gravimetrically. The resulting anterior-posterior translation and tibial rotation position was measured throughout the study.

RESULTS

The mean UHMWPE wear rate was 0.57 ± 0.71 and 1.24 ± 2.0 mm3/million cycles for SAIPH and MRK total knee replacement systems respectively with no significant difference in wear (p = 0.24). Analysis of simulator output kinematics showed a larger range of anterior-posterior motion for SAIPH total knee replacements compared to MRK. The magnitude of tibial rotation was low for both knee replacement systems.

CONCLUSION

The small magnitude of anterior-posterior displacement and tibial rotation motion demonstrates the inherent stability of this knee system design offered by the constrained medial compartment. This study shows the potential for medially stabilised knee systems as a low polyethylene surface wear solution.

Current advancements in therapeutic approaches in orthopedic surgery: a review of recent trends

Recent advancements in orthopedic surgery have greatly improved the management of musculoskeletal disorders and injuries. This review discusses the latest therapeutic approaches that have emerged in orthopedics. We examine the use of regenerative medicine, including stem cell therapy and platelet-rich plasma (PRP) injections, to accelerate healing and promote tissue regeneration. Additionally, we explore the application of robotic-assisted surgery, which provides greater precision and accuracy during surgical procedures. We also delve into the emergence of personalized medicine, which tailors treatments to individual patients based on their unique genetic and environmental factors. Furthermore, we discuss telemedicine and remote patient monitoring as methods for improving patient outcomes and reducing healthcare costs. Finally, we examine the growing interest in using artificial intelligence and machine learning in orthopedics, particularly in diagnosis and treatment planning. Overall, these advancements in therapeutic approaches have significantly improved patient outcomes, reduced recovery times, and enhanced the overall quality of care in orthopedic surgery.

Modern robotics platform associated with reduced 90-day complications in hospital setting

BACKGROUND

Early complications in total knee arthroplasty (TKA) associated with modern robotics platforms integrated with digital balancing technology have not been investigated.

OBJECTIVE

The objective was to compare 90-day complication rates between a manual technique and a modern robotic-assisted ligament balancing TKA platform.

METHODS

895 primary TKA procedures from a single surgeon were retrospectively reviewed (614 manual TKA, 281 using a modern robotics platform with an integrated digitally controlled ligament balancing device). Post-operative complications within the 90-day episode of care were recorded by the Michigan Arthroplasty Registry Collaborative Quality Initiative. Differences in complication rates between techniques were further divided into inpatient hospital, outpatient hospital, and ambulatory surgery center (ASC) cohorts.

RESULTS

In the pooled hospital cohort and inpatient hospital cohort, 'Return to OR' was significantly lower for the robotic assisted group (1.3% vs 5.2% and 0% vs 4.9%, respectively, p< 0.0370). Specifically, the need for manipulation under anesthesia (MUA) was reduced for the robotics group (0.0% vs 2.5%, p= 0.0352). No differences in overall complication rate or cause of complication was found between manual and robotics cases for the hospital outpatient and ASC cohorts (p⩾ 0.68).

CONCLUSION

Within the hospital setting, robotic assisted ligament balancing technology was associated with reduced 90-day postoperative complications for 'Return to OR' and MUA.

Technology assistance in primary total knee replacement: hype or hope?

INTRODUCTION

Total knee replacement (TKR) reduces pain, it increases quality of life and it generally lasts a long time with revision rates of less than 5% at 10 years. Some authors have suggested that outcomes may be further improved by technology assistance.

AREAS COVERED

Technology assistance in primary TKR includes technologies such as navigated TKR, patient specific instrumentation TKR and robotic TKR.

EXPERT OPINION

In general, technology assistance results in higher accuracy of component positioning and alignment, but this is likely not clinically relevant as no clinically important difference in clinical outcomes, quality of life and complications such as revisions has been demonstrated in meta-analyses of randomized controlled trials. As technology assistance in primary TKR is increasingly used to capture patient and surgeon data, surgeons have an increasingly important role in protecting their patients' data and their own data. Real world evidence of implant registries has shown that TKR without technologically assistance can achieve perfectly acceptable outcomes. Although there is a genuine hope that technology-assisted TKR may further improve these outcomes, this hope is based on promises rather than solid evidence. At the same time, technology assisted TKR is heavily promoted including direct patient marketing, which are aspects of a hype.

Revolutionizing orthopedics: a comprehensive review of robot-assisted surgery, clinical outcomes, and the future of patient care

Robotic-assisted orthopedic surgery (RAOS) is revolutionizing the field, offering the potential for increased accuracy and precision and improved patient outcomes. This comprehensive review explores the historical perspective, current robotic systems, advantages and limitations, clinical outcomes, patient satisfaction, future developments, and innovation in RAOS. Based on systematic reviews, meta-analyses, and recent studies, this article highlights the most significant findings and compares RAOS to conventional techniques. As robotic-assisted surgery continues to evolve, clinicians and researchers must stay informed and adapt their practices to provide optimal patient care. Evidence from published studies corroborates these claims, highlighting superior component positioning, decreased incidence of complications, and heightened patient satisfaction. However, challenges such as costs, learning curves, and technical issues must be resolved to fully capitalize on these advantages.

Intra-operative Safety of an Autonomous Robotic System for Total Knee Replacement: A Review of 500 Cases in India

Background

Manual total knee arthroplasty (TKA) has been documented several times for their safety and complications data. In contrast, there is a limited evidence-based analysis for safety and complications of autonomous robotic-assisted (RA)-TKA. This study aimed to evaluate the safety features and intra-operative surgical complications associated with the use of Cuvis Joint™ autonomous robotic system for TKA.

Methods

The study included 500 consecutive patients who underwent TKA using the Cuvis Joint™ autonomous robotic system from November 2020 to November 2021. All surgeries were performed by a senior surgeon. Patients in whom the surgery was abandoned midway due to technical errors, were excluded from the analysis. In case of unilateral abandonment of the robotic arm during a bilateral RA-TKA, data of the side on which the surgery was completed with robotic assistance was recorded.

Results

There was no incidence of neurological injury, vascular injury, extensor mechanism disruption, or medial collateral ligament injury. There was one case of superficial abrasion of the patellar tendon; however, it did not require any intervention. There were no cases of midway abandonment due to threatened soft tissue injury. There was no intra-operative pin loosening or stress-related fractures at the pin sites. There was one case of Steinmann pin breakage and another case of drill bit breakage, which were removed without any damage to the bone.

Conclusion

The Cuvis Joint™ autonomous robotic system for TKA is safe with no significant intra-operative complications.

Image-free handheld robotic-assisted technology improved the accuracy of implant positioning compared to conventional instrumentation in patients undergoing simultaneous bilateral total knee arthroplasty, without additional benefits in improvement of clinical outcomes

PURPOSE

The purpose of this study was to compare the clinical and radiological outcomes in patients who underwent simultaneous bilateral total knee arthroplasty (SB-TKA) using either robotic-assisted TKA (RA-TKA) or conventional TKA (C-TKA).

METHODS

Included were the patients who underwent SB-TKA between January 2018 and January 2020 and had a minimum follow-up of 2 years. Of 151 patients included, 117 patients were operated using an image-free handheld robotic sculpting system (RA-TKA group) and 34 patients operated using conventional instrumentation (C-TKA group). The key outcomes noted were multiple patient-reported outcomes (PROs), adverse events, and radiological outcomes. Two investigators independently measured the radiological outcomes on pre- and post-operative radiographs in coronal plane (medial proximal tibial angle [MPTA] and anatomic lateral distal femoral angle [aLDFA]) and sagittal plane (posterior tibial slope [PTS] and posterior condylar offset [PCO]). The chi-square test was used to examine categorical variables. Student's t test was used to analyze the continuous variables.

RESULTS

Patients in both groups were similar in baseline characteristics (gender, body mass index, incidence of comorbidities, and length of hospital stay) except that RA-TKA group patients younger (66.7 ± 8.9 vs 70.4 ± 10.5, P = 0.037) than C-TKA group. The operative time was longer in RA-TKA group as compared to C-TKA (189.3 ± 37.1 vs 175.0 ± 28.2, P = 0.040). The final PROs at each were similar between the two groups (P > 0.05). The values of PROs at final follow-up in RA-TKA compared to C-TKA were VAS pain (0.4 ± 0.9 vs 0.4 ± 0.5), KOOS-JR (89.3 ± 5.8 vs 87.1 ± 5.3), and physical (55.9 ± 2.8 vs 55.4 ± 3.2), mental (61.1 ± 4.4 vs 60.2 ± 4.7) component of VR-12 scores, and KSS satisfaction (37.5 ± 1.1 vs 37.1 ± 2.2) (all P > 0.50 or non-significant [n.s.]). While one patient in RA-TKA required revision of femoral component for peri-prosthetic fracture, none of the patient in conventional group were revised (0.85% vs 0%, P = n.s.). The proportion of patients with outliers in RA-TKA group was lower for aLDFA (2.6% vs 22.1%, P < 0.01) and PTS (0% vs 35%, P < 0.01).

CONCLUSION

This comparative study in patients undergoing SB-TKA found reduction of outliers in femoral and tibial implant positioning with RA-TKA as compared to C-TKA. There were no differences in both groups for pain, function, and satisfaction at a minimum of 2 years of follow-up.

LEVEL OF EVIDENCE

III Therapeutic Study.

NAVIO RATKA shows similar rates of hemoglobin-drop, adverse events, readmission and early revision vs conventional TKA: a single centre retrospective cohort study

PURPOSE

Despite widespread adoption of NAVIO robotic-assisted total knee arthroplasty (NAVIO RATKA) in clinical practice, clinical outcome in terms of adverse events and complications remains unclear. The purpose of this study was to compare adverse events, length of stay, surgical time, hemoglobin drop, early readmission rate and revision rate between conventional TKA (CTKA) and NAVIO RATKA.

METHODS

This single-centre retrospective cohort analysis compared 230 NAVIO RATKA patients to 489 CTKA patients with a minimal follow-up of 12 months. Baseline demographic and comorbidity parameters were collected, as well as length of stay, revision rate and reason for revision, early readmission rate (< 6w) and reason for readmission, post-operative hemoglobin levels, adverse events, surgical time and operating room time. Data were compared using Mann-Whitney U test for continuous data without normal distribution and ordinal data, categorical variables were compared using the Chi-square or Fisher exact test.

RESULTS

There were no clinically relevant baseline demographic or comorbidity differences between groups. CTKA had shorter length of stay than NAVIO RATKA (5.0 days vs 5.4 days, p = 0.010) but trended towards a higher reoperation rate (4.1% vs 1.7%, p = .144, n.s). No differences were found in hemoglobin drop, readmission rate or overall incidence of adverse events, but CTKA showed more hematoma formation (1.6% vs 0%, p = .044) and higher incidence of periprosthetic joint infection (PJI) (1% vs 0%, p = n.s.), whilst NAVIO RATKA showed more periprosthetic fractures and persistent wound drainage (0.4% vs 2.2%, p = .038 and 0.6% vs 4.3%, p = .001, respectively). Surgical time remained significantly longer in NAVIO RATKA during all 230 cases (87 min vs 67.6 min) and showed a continuous downward trend.

CONCLUSIONS

This study further validates the usage of NAVIO RATKA as a safe method to perform TKA, with comparable short term outcomes to CTKA in terms of early revisions and adverse events. Surgeons should be mindful of the differing adverse event profile in NAVIO RATKA and adjust their patient selection accordingly to ensure optimal outcomes. In addition, surgeons using NAVIO RATKA should expect a linear learning curve and a surgical time exceeding that of CTKA.

LEVEL OF EVIDENCE

Level III (therapeutic retrospective cohort study).

A comparison of robotic-assisted and manual techniques in restricted kinematically aligned total knee arthroplasty: coronal alignment improvement with no significant clinical differences

PURPOSE

The purpose of this study was to compare radiographic and clinical outcomes of robotic-assisted and conventional manual techniques in restricted kinematically aligned TKA.

METHODS

Patients who underwent either manual or robotic-assisted restricted kinematically aligned TKA between 2019 and 2020 were included in this retrospective comparative study. Radiographic outcomes comprised coronal plane measurements performed through standing full-length anteroposterior radiographs. The Knee Injury and Osteoarthritis Outcome Score (KOOS), Oxford score, Visual Analog Scale pain and satisfaction score, and Forgotten Joint Score were used to determine the clinical outcome. The continuous data were compared by Student's t test according to the Kolmogorov‒Smirnov normality test.

RESULTS

The manual group consisted of 46 patients (38 females, eight males) with a mean age of 68.1 years, and the robotic group consisted of 70 patients (58 females, 12 males) with a mean age of 65.7 years (n.s.). Preoperatively, no significant difference was observed between groups concerning demographic characteristics, radiographic measurements, and clinical scores except for the symptom and pain domains of the KOOS score, which was significantly worse in the manual group (p = 0.011 and 0.035, respectively). At the postoperative 2-year follow-up, we observed significant differences between groups with respect to the mean HKA angle, mMPTA, and mLDFA (p = 0.034, 0.041, and 0.005, respectively). A comparison of clinical scores at the postoperative 2-year follow-up demonstrated no significant differences between groups.

CONCLUSION

The current study demonstrated that using robotic-assisted technique for restricted kinematically aligned total knee arthroplasty (TKA) resulted in significantly better outcomes compared to the conventional manual technique in achieving normal ranges of lower extremity coronal alignment measurements. While the robotic-assisted group demonstrated better clinical scores, there was no statistically significant difference in clinical outcomes between the robotic-assisted group and the control group at the two-year follow-up. Concerning clinical relevance, the restoration of original anatomy and coronal alignment, a crucial concern in restricted kinematically aligned TKA, may be better achieved by the robotic-assisted technique.

LEVEL OF EVIDENCE

Level III (Retrospective cohort study).

Robotic-assisted mechanically aligned total knee arthroplasty does not lead to better clinical and radiological outcomes when compared to conventional TKA: a systematic review and meta-analysis of randomized controlled trials

PURPOSE

Robotic-assisted total knee arthroplasty (R-TKA) has emerged as an alternative to improve the results of the conventional manual TKA (C-TKA). The aim of this study was to analyse the high-level studies comparing R-TKA and C-TKA in terms of clinical outcomes, radiological results, perioperative parameters, and complications.

METHODS

The literature search was conducted on three databases (PubMed, Cochrane, and Web of Science) on 1 February 2023 according to the guidelines for Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). Inclusion criteria were: randomized controlled trials (RCTs), written in English language, published in the last 15 years, focusing on the comparison of C-TKA and R-TKA results. The quality of each article was assessed using the Cochrane risk-of-bias tool for randomized trials version 2 (RoB 2). The statistical analysis was carried out using random effects (DerSimonian & Laird) for weighted mean difference (MD) of the continuous variables and Peto method for odds ratios of the dichotomous variables.

RESULTS

Among the 2905 articles retrieved, 14 RCTs on 12 series of patients treated with mechanically aligned implants were included. A total of 2255 patients (25.1% males and 74.9% females; mean age 62.9 ± 3.0; mean BMI 28.1 ± 1.3) were analysed. The results of this systematic review and meta-analysis showed that R-TKA did not provide overall superior results compared to C-TKA in mechanically aligned implants in terms of clinical and radiological outcomes. R-TKA showed longer operative time (MD = 15.3 min, p = 0.004) and similar complication rates compared to C-TKA. A statistically significant difference in favour of R-TKA was found in the posterior-stabilized subgroup in terms of radiological outcomes (hip-knee-ankle angle MD = 1.7, p < 0.001) compared to C-TKA, although without resulting in appreciable difference of clinical outcomes.

CONCLUSION

R-TKA did not provide overall superior results compared to C-TKA in terms of clinical and radiological outcomes, showing longer operative time and similar complication rates.

LEVEL OF EVIDENCE

Level I.

Safe Zones and Trajectory of Femoral Pin Placement in Robotic Total Knee Arthroplasty

Background

Robotic-assisted total knee arthroplasty may result in array pin-related complications. Lack of knowledge on ideal pin placement results in varied insertion sites and trajectory, with unknown risks to surrounding neurovascular structures.

Methods

This study included 10 lower-extremity magnetic resonance images. Images were subdivided into 6 zones of study. Zones consisted of a correlating axial image with femoral pin placement replicated by drawing a line angled 45° from the anterior to posterior reference in the anteromedial to posterolateral femoral quadrants. The distances from the pin paths to the neurovascular structures were measured.

Results

Zone 2C demonstrated femoral pin trajectory an average of 14 mm from the femoral artery/vein. In Zone 2B, proximity increased to an average of 30 mm to the femoral artery and 29 mm to the femoral vein. At Zone 1A, the popliteal artery and vein were on average 22 mm from the femoral pin, while the common peroneal nerve was an average of 21 mm. Placing pins in Zone 1A poses a high risk of injury to the genicular arteries. Women demonstrated greater proximity to neurovascular structures than men in 66% of the sites (P < .05).

Conclusions

This classification system for safe zones and trajectory of femoral pin placement in robotic-assisted total knee arthroplasty demonstrates that proximally, the profunda femoris and femoral artery/vein are at risk of injury, while distally, the genicular arteries, common peroneal nerve, and popliteal artery/vein are at risk. Caution should be exercised if femoral pins are inserted with an angle less than 45°, especially in women.

Mapping knowledge landscapes and emerging trends of robotic-assisted knee arthroplasty: A bibliometric analysis

The robotic-assisted knee arthroplasty has gained increasing attention in the research field. To date, no comprehensive bibliometric analysis has been carried out on this topic. The present study aimed to introduce the research status and hotspots and explore the field of robotic-assisted knee arthroplasty from a bibliometric perspective. The Web of Science Core Collection database was utilized to retrieve articles and reviews on robotic-assisted knee arthroplasty published between 1993 and 2023. CiteSpace, VOSviewer, Scimago Graphica, Pajek, and a bibliometric online analysis platform (http://bibliometric.com/) were employed to analyze the regions, institutions, journals, authors, and keywords, aiming to predict the latest trends in research related to robotic-assisted knee arthroplasty. This study encompasses 697 records. The annual publication count pertaining to robotic-assisted knee arthroplasty demonstrates consistent growth. The United States leads with the highest number of studies (298), trailed by the United Kingdom (110) and France (49). The Hospital for Special Surgery emerges as the most prolific institution, while Professor Mont, Michael A holds significant author influence. The Journal of Arthroplasty reigns supreme in this field, boasting the highest publication and citation figures. Funding sources predominantly include Stryker (34), Smith Nephew (19), and the National Natural Science Foundation of China (17). Noteworthy research themes within robotic-assisted knee arthroplasty encompass patient satisfaction, kinematic alignment, and clinical benefits. The landscape of robotic-assisted knee arthroplasty research is thriving. Anticipated trajectories of research will be geared toward refining the precision of robotic technology and enhancing clinical outcomes within the realm of robotic-assisted knee arthroplasty.

Total Knee Arthroplasty in Paget's Disease using 3D-Printed Patient-Specific Femoral Jig - A Case Report

Introduction

Patients with Paget's disease develop abnormal bony anatomy which can result in significantly altered lower limb alignment predisposing them to early secondary osteoarthritis. Due to the severe extra-articular deformity, total knee arthroplasty (TKA) in these patients is challenging. Conventional knee arthroplasty using intramedullary guides is not an option and can lead to erroneous limb alignment postoperatively. Patient-specific instrumentation (PSI) is a simple solution in such complex primary knee arthroplasty.

Case Report

A 70-year-old male patient presented with a severe left femur deformity and left knee pain. He was diagnosed to have monostotic Paget's disease of the left femur with tricompartmental osteoarthritis of the left knee. After reduction in pathological bone turnover, the patient was planned for a total knee replacement. As a standard intramedullary femoral jig was not applicable due to the femoral deformity, a computed topography-based 3D-printed patient-specific instrument was used. This custom jig was used to define and perform the distal femur cut at 90 degrees to the mechanical axis of the femur in the coronal and sagittal plane. Postoperatively, the patient did well and achieved good function and pain relief.

Conclusion

The use of a 3D-printed PSI for complex primary knee arthroplasty is an excellent option with no additional operative time than a conventional knee arthroplasty. Although a robotic or computer-navigated TKA would be an excellent option in this case, we restored the limb alignment using a cost-effective patient-specific femoral jig. This could be a viable option in centers without navigation or robotic arthroplasty.