Robotic-assisted Total Knee Arthroplasty Research Articles

Simultaneous Evaluation of Bone Cut and Implant Placement Accuracy in Robotic-Assisted Total Knee Arthroplasty.

Background: This study aimed to evaluate the accuracy of bone cuts and implant placements, simultaneously, for total knee arthroplasty (TKA) performed using a system with an active robotic arm. Methods: Two experienced orthopaedic surgeons performed TKA on ten cadaveric legs. Computed tomography scans were performed to compare the bone cuts and implant placements with the preoperative planning. The differences between the planned and actual bone cuts and implant placements were assessed using positional and angular errors in the three anatomical planes. Additionally, the cut-implant deviations were calculated. Statistical analysis was performed to detect systematic errors in the bone cuts and implant placements and to quantify the correlations between these errors. Results: The root-mean-square (RMS) errors of the bone cuts (with respect to the planning) were between 0.7-1.5 mm and 0.6-1.7°. The RMS implant placement errors (with respect to the planning) varied between 0.6-1.6 mm and 0.4-1.5°, except for the femur and tibia in the sagittal plane (2.9°). Systematic errors in the bone cuts and implant placements were observed, respectively, in three and two degrees of freedom. For cut-implant deviations, the RMS values ranged between 0.3-2.0 mm and 0.6-1.9°. The bone cut and implant placement errors were significantly correlated in eight degrees-of-freedom (ρ ≥ 0.67, p < 0.05). Conclusions: With most of the errors below 2 mm or 2°, this study supported the value of active robotic TKA in achieving accurate bone cuts and implant placements. The findings also highlighted the need for both accurate bone cuts and proper implantation technique to achieve accurate implant placements.

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

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. 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. 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. 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.

Analysis of robot-specific operative time and surgical team anxiety level and its effect on alignment during robot-assisted TKA.

Adapting to robotic-assisted (RA) total knee arthroplasty (TKA) is hindered by the surgeon's fear of extra time. The main purpose of this study was to determine the robot's operative time, and the secondary goals were to assess the surgical team's anxiety, implant location and size, and limb alignment. From February to April 2022, 40 participants participated in prospective research. The study included primary Cuvis joint active RA-TKA patients for end-stage arthritis, but conversion of unicompartmental knee arthroplasty to TKA, and patients with prior knee surgery were excluded. The active RA-TKA surgical time included surgeon-dependent and surgeon-independent/active robot time. The surgeon's anxiety was measured using the state-trait anxiety inventory (STAI). The implant size/position and limb alignment were checked by post-operative weight-bearing lateral, anteroposterior, and full-length scanograms. Operative time specifically related to active RA-TKA was higher in the first 10 cases as against 10-20, 20-30 and 30-40 cases which was observed to lower from cohort 2. A similar trend was observed for the surgical team's anxiety levels which seem to lower from cohort 2 (case 10-20). Cumulative experience of active RA-TKA showed no effect on the precision of implant alignment/ size, limb alignment and complications. The study showed progressive improvement in the surgical anxiety scores and reduction in operating time indicating the proficiency gained by the surgical team. Further no learning curve was involved in achieving the implant positioning and sizing, limb alignment with the absence of complications.

Functional alignment in robotic-assisted total knee arthroplasty: a systematic review.

The present study systematically reviewed current evidence on functional alignment (FA) in robotic total knee arthroplasty (TKA), discussing advantages and limitations, possible pitfalls, and prospects. This study was conducted according to the 2020 PRISMA statement. In August 2023, the following databases were accessed: PubMed, Web of Science, Google Scholar, and Embase with no additional filters or time constraints. All the clinical studies investigating functional alignment in robotic TKA were accessed. Only studies published in peer-reviewed journals were considered. The risk of bias was evaluated following the guidelines in the Cochrane Handbook for Systematic Reviews of Interventions. Non-randomized controlled trials (non-RCTs) were evaluated using the Risk of Bias in Nonrandomised Studies of Interventions (NRSI) (ROBINS-I) tool. Data from 1198 patients (seven studies) were retrieved. The mean length of the follow-up was 17.1 ± 6.4months. The mean age was 67.2 ± 5.4years, and the mean BMI was 30.9 ± 2.7kg/m2. FA might improve resection accuracy, implant alignment, and gap balancing in TKA, and additional high-quality clinical trials are necessary to properly establish the superiority of FA to other alignment techniques in TKA. Long-term clinical trials are needed to investigate the impact of FA on implant survivorship. Level IV, systematic review and meta-analysis.

Two- and three-dimensional evaluations following handheld robot-assisted total knee arthroplasty.

Robot-assisted total knee arthroplasty (TKA) has proven to be successful in improving the accuracy of component positioning and reducing radiographic outliers. This study aimed to evaluate and compare the alignment of the components using two- and three-dimensional (2D and 3D) measurements following handheld imageless robot-assisted TKA. Seventy consecutive patients underwent primary TKA at our institution using a handheld robot-assisted system. Full-length standing anteroposterior and lateral radiographs were obtained 2weeks after surgery for assessment of 2D component alignments. Pre- and postoperative computed tomography (CT) images were obtained to assess 3D component alignment. The reference points defined on preoperative CT images were transferred to the postoperative CT images. The absolute errors in the 2D and 3D component alignments from the planned, validated cutting, and validated implantation angles were calculated. Outliers of > ± 3° of femoral and tibial component alignments in the coronal and sagittal planes were also investigated. All absolute errors in the 2D and 3D component alignments were < 1°, except for the planned and validated cutting angles of the femoral sagittal alignment. No outliers were observed in the femoral or tibial component in the coronal plane. Significant differences between the 2D and 3D measurements were observed for the mean absolute value from the planned and validated cutting angles in the femoral sagittal plane and from the validated implantation angle in the tibial coronal plane. The handheld robot-assisted system demonstrated a high accuracy for component alignment using 2D and 3D evaluations.

Predictability of implant sizes during cruciate-retaining total knee arthroplasty using an image-free hand-held robotic system.

The use of appropriately sized implants is critical for achieving optimal gap balance following total knee arthroplasty (TKA). Inappropriately sized implants could result in several complications. Robot-assisted TKA (RA-TKA) using CT-based pre-operative planning predicts implant sizes with high accuracy. There is scant literature describing the accuracy of image-free RA-TKA in predicting implant sizes. The purpose of this study was to assess the accuracy of an image-free robotic system in predicting implant sizes during RA-TKA. Patients who underwent cruciate-retaining RA-TKA for primary osteoarthritis, using an image-free hand-held robotic system were studied. The predicted and implanted sizes of the femoral component, tibial component and polyethylene insert, for 165 patients, were recorded. Agreement between robot-predicted and implanted component sizes was assessed in percentages, while reliability was assessed using Cohen's weighted kappa coefficient. The accuracy of the robotic system was 63% (weighted-kappa = 0.623, P < 0.001), 94% (weighted-kappa = 0.911, P < 0.001) and 99.4% (weighted-kappa = 0.995, P < 0.001), in predicting exact, ± 1 and ± 2 sizes of the femoral component, respectively. For the tibial component, an accuracy of 15.8% (weighted-kappa = 0.207, P < 0.001), 55.8% (weighted-kappa = 0.378, P < 0.001) and 76.4% (weighted-kappa = 0.568, P < 0.001) was noted, for predicting exact, ± 1 and ± 2 sizes respectively. An accuracy of 88.5%, 98.2% and 100%, was noted for predicting exact, ± 1 and ± 2 sizes of the polyethylene insert respectively. Errors in predicting accurate implant sizes could be multi-factorial. Though the accuracy of image-free RA-TKA with respect to alignment and component positioning is established, the surgeon's expertise should be relied upon while deciding appropriate implant sizes.

Revision Total Knee Arthroplasty With an Imageless, Second-Generation Robotic System

BackgroundRobotic-assisted total knee arthroplasty is increasingly used in revision total knee arthroplasty (rTKA), with imageless systems recently receiving Food and Drug Administration (FDA) approval. However, there remains a paucity of literature on the use of robotic assistance in revision total knee arthroplasty (TKA). This paper describes the imageless surgical technique for robotic revision TKA using a second-generation robotic system and details both intraoperative and 90-day outcomes. MethodsThis was a retrospective review of 115 robotic revision TKAs from March 2021 to May 2023 at 3 tertiary academic centers. Patient demographics, perioperative surgical data, and 90-day outcomes were collected. Pain and Patient-Reported Outcomes Measurement Information System scores preoperatively and postoperatively were recorded. All-cause reoperations at the final follow-up were detailed. The mean patient age was 65 years (range, 43 to 88), and 58% were women. The mean follow-up time was 13 months (range, 3 to 51). ResultsThe most common indications for rTKA were instability (n = 37, 32%) and aseptic loosening (n = 42, 37%). There were 83 rTKAs to a posterior-stabilized liner, 22 to a varus-valgus constrained liner, and 5 to a hinged construct. The median polyethylene size was 11 (interquartile range, 10 to 13), and 93% of patients had their joint line restored within 5 millimeters of the native contralateral knee. Within the 90-day postoperative window, there were 8 emergency department visits and 2 readmissions. At the final follow-up, there were 5 reoperations and 2 manipulations under anesthesia. There were 4 patients who required irrigation and debridement after superficial wound dehiscence, and one had an arthrotomy disruption after a fall. ConclusionsThis review demonstrates favorable intraoperative and 90-day outcomes and suggests that imageless robotic surgery is a promising modality in rTKA. Further studies comparing the longitudinal outcomes after robotic and conventional rTKA are warranted.

Does high body mass index affect short-term clinical and radiologic outcomes in robotic-assisted total knee arthroplasty?

The purpose of this study was to determine whether high BMI affect short-term clinical and radiologic outcomes of robotic-assisted total knee arthroplasty (TKA) by comparing the clinical outcomes, radiologic outcomes and complications between high BMI and normal patients. We retrospectively compared the short-term clinical and radiological outcomes of 424 knees (408 patients). The patients were divided into four groups: BMI < 24.9kg/m2 (normal); BMI between 25.0 and 29.9kg/m2 (overweight); BMI between 30.0 and 34.9kg/m2 (obese class I) and BMI between 35.0 and 39.9kg/m2 (obese class II). Clinical and radiologic outcomes were evaluated. There was no significant difference in radiologic outcomes between those groups (p > .05). Furthermore, there was no significant difference in operation time, drainage volume, fall in hemoglobin, post-operative CRP and complications, including periprosthetic fracture and periprosthetic joint infection (PJI), between those groups. High BMI does not affect short-term clinical and radiologic outcomes in robot-assisted TKA.

Robotic-assisted total knee arthroplasty improves implant position and early functional recovery for the knee with severe varus/valgus deformity

PurposeRobotic-assisted total knee arthroplasty (r-TKA) facilitates precise bone resection and lower limb alignment, yet accuracy and functional recovery for severe varus/valgus deformity is not well-documented. The aim of study was to investigate whether r-TKA improves implant alignment in the coronal and sagittal view and early functional recovery compared to conventional TKA(c-TKA).MethodsThis comparative study included 86 patients with symptomatic knee arthritis who underwent primary TKA at our institution between 1st May and 31th November 2021. Radiological parameters evaluated included hip-knee-ankle angle (HKAA), femoral varus-valgus angle (FVVA), tibial varus-valgus angle (TVVA), posterior tibial slope angle (PTSA), femoral sagittal angle (FSA), posterior condylar offset ratio, and Insall-Salvati index. Operative time, stay length, and complications were reviewed from patient records. The hospital for special surgery (HSS), Visual Analogue Scale (VAS) and knee joint motion range were evaluated at the six-month follow-up.ResultsThe c-TKA and r-TKA groups had no significant differences in HKAA (179.73 ± 3.76°, range: 172.10-188.90° vs. 180.53 ± 2.91°, range: 173.30-188.32°, p = 0.277), FVVA (96.13 ± 2.61°, range: 90.27-101.52° vs. 96.38 ± 2.23°, range: 90.98-100.95°, p = 0.636), and TVVA (88.74 ± 2.03°, range: 83.75–92.74° vs. 89.43 ± 1.83°, range: 85.32–94.15°, p = 1.000). Outlier of mechanical alignment incidence (> 3°) was significantly lower in r-TKA compared with c-TKA, 17.50% (7/40) vs. 41.30% (19/46), (p = 0.017). PTSA of r-TKA remained significantly lower than c-TKA (p = 0.009) in mild-deformity patients. For severe varus/valgus deformity, r-TKA had a significantly lesser HKAA-outlier incidence (p = 0.025), PTSA-outlier incidence (p = 0.019), and lower PTSA (p < 0.001) compared with c-TKA. The r-TKA functional outcome was better than c-TKA regarding HSS (93.12 ± 1.97, range: 90–95, 95%CI:92.11–94.13 vs. 91.33 ± 2.50, range: 85–95, 95%CI:90.20-92.69, p = 0.036), and VAS (0.24 ± 0.44, range:0–1 vs. 0.72 ± 0.75, range:0–2, p = 0.026), knee joint flexion (118.53° ± 8.06, range: 105–130°, 95%CI:114.39-122.67° vs. 112.22 ± 8.09°, range: 100–130°, 95%CI:108.20-116.24° ,p = 0.027) for severe varus/valgus deformity.Conclusionr-TKA improved lower-limb coronal alignment, sagittal implant position, and early functional recovery for patients with severe varus/valgus deformity of the knee. r-TKA did not confer substantial advantages over c-TKA in both radiological and clinical outcomes for the mild varus/valgus deformity.

Comparison of Time Taken in Conventional versus Active Robotic-Assisted Total Knee Arthroplasty.

Computer- and robotic-assisted total knee replacement procedures have been shown to improve the accuracy of the implant size. It also allows dynamic confirmation of the implant and limb alignment during total knee arthroplasty (TKA). The major inhibition of the arthroplasty surgeon in adapting to the robotic-assisted TKA (RA-TKA) is the extra time spent during the registration process and milling of the bone with the robot. The aim of the study was to ascertain the extra time spent during these 2 steps as compared to the conventional TKA (C-TKA). It is a prospective study involving 30 patients each in the conventional TKA and RA-TKA operated by the same surgical team. The patients were given a choice between the C-TKA and RA-TKA and consecutive 30 cases in each group were studied by an independent observer. In the C-TKA group, the time for the application of appropriate zigs and execution of the bone cuts and soft-tissue release was recorded whereas in the RA-TKA group, the time taken for fixation of the tibial and femoral arrays and bone registration and bone milling with robot and required soft-tissue release was measured. The preoperative patient characteristics were the same in both groups. The time taken in the C-TKA and RA-TKA groups was 24.77 ± 1.92 minutes and 25.03 ± 3.27 minutes, respectively, which is statistically insignificant (p = 0.709). The study findings show that RA-TKA does not take additional time than C-TKA.

Patient Perception of Robotic Total Knee Arthroplasty: A Qualitative Study

Introduction: Total knee arthroplasty (TKA) is one of the most commonly performed orthopedic surgeries. The goal of robotic-assisted technology is to optimize outcomes through preoperative planning, ensuring accuracy in component sizes and precision in bone cuts. There is a paucity of literature that addresses patient perceptions of this new technology. Therefore, the purpose of this study was to assess why patients choose to undergo robotic-assisted TKA. Methods: All patients who underwent robotic-assisted TKA between July 1, 2017, and December 31, 2018, were given a 12-question survey to complete. The final cohort consisted of 76 patients composed of 51 women and 25 men with a mean age of 71 years (range, 51–88 years). All de-identified data was evaluated and tabulated for assessment. Results: Eighty-three percent stated they would recommend undergoing robotic-assisted TKA as opposed to conventional TKA with 72% stating the main influencer in their decision was physician input. Fifty-seven percent stated they thought their components would be placed in a more optimal position using robotics. Sixty-two percent believed they would achieve better outcomes with robotic TKA as opposed to their conventional counterparts. Among outcome questions, 55% believed they would have less pain with robotic-assisted TKA. However, the majority of the cohort stated they would have no difference in length-of-stay or infection risk compared to manual TKA. Exactly 50% of patients stated there would be similar operating room time between robotic and manual TKA. Discussion: The vast majority of our cohort believed there were benefits in opting for robotic-assisted TKA. Future studies should evaluate how attitudes and beliefs may influence patient-reported satisfaction and outcomes in the long term.

Intraoperative patellar tracking assessment during image-based robotic-assisted total knee arthroplasty: technical note and reliability study.

Restoration of the anterior knee compartment is increasingly studied with the development of personalized surgery. However, evaluating the patellar tracking during the surgery is still subjective and at the surgeon's discretion. This study aimed 1) to describe the assessment of the patellar tracking during robotic-assisted total knee arthroplasty (TKA), 2) to describe a new measurement technique for evaluating the evolution of this patellar tracking, and 3) to assess its reliability and repeatability. This monocentric study assessed the evolution of patellar tracking for 20 robotic-assisted TKA. The sharp probe was used to perform patellar tracking in all the arcs of knee flexion before and after the bone cuts. The patella positioning was recorded every 10° of flexion between the full extension and 90° knee flexion and was assessed in the coronal and sagittal planes. For the measurements of the patellar tracking, we used a sagittal view and a coronal view of the knee on the MAKO software. From these two views, the difference between the patellar tracking before and after the bone cuts with the definitive implants was measured. Two independent reviewers performed the measurements to assess their reliability. To determine intraobserver variability, the first observer performed the measurements twice. The mean age was 68.7years old±5.2 [61;75], the mean body mass index was 28.8kg/m2±4.2 [21.4; 36.2], the mean HKA angle was 176.3°±3.7° [174.1.4;179.7]. The radiographic measurements showed very good to excellent intra-observer and inter-observer agreements (0.60 to 1.0). This new measurement technique assessed the evolution of patellar tracking after TKA with good inter and intra-observer reliability.

An observational study on the functional outcomes of 100 robotic total knee replacements performed by an Indian surgeon: Early experiences

Abstract Background: We aim to share our preliminary encounter with robotic knee replacements in Indian patients, focusing on the initial 100 cases. This report will delve into our observations regarding the learning curve and provide insights from a short-term follow-up at 6 months. Materials and Methods: Following institutional ethical clearance, we conducted an observational study involving 100 robotic-assisted total knee replacement cases performed from March 2022 to November 2022. These patients underwent a 6-month follow-up to evaluate functional outcomes. Our primary objective was to investigate the learning curve associated with robotic-assisted total knee arthroplasty (RATKA), specifically emphasizing operative time. Furthermore, we examined preoperative and postoperative alignment parameters as part of our analysis. Results: In our investigation, participants had a mean age of 64.68 years, with a female-to-male ratio of 43:22 and an average body mass index of 30.71 ± 4.88. Intraoperative blood loss was recorded at an average of 91.81 ± 21.63 mL. The mean surgical duration for the initial 25 cases was 102.5 ± 11.08 min, which improved to 65.65 ± 13.07 min for the subsequent 75 cases. The average hospital stay length was 2.88 ± 0.88 days. Notably, there was a significant enhancement in the Knee Society Score (KSS), with a preoperative mean of 38.90 ± 12.72 improving to a postoperative mean of 84.89 ± 4.10 (P = 0.001), as well as in the Oxford Knee Score (OKS), which saw a rise from 16.62 ± 16.42 preoperatively to 45.58 ± 4.97 postoperatively (P = 0.001). The accuracy of preoperative determination for femoral component sizes was 100%, while for tibial component sizing, it was 97%. Conclusion: The key finding from this observational study suggests that around 25 procedures are required to reach a learning plateau. During this process, an average decrease of 36.1 min in surgical time was observed from the initial to proficient stages. Notably, no learning curve was observed for lower limb alignment and implant placement, and no significant complication rates were documented.

Robotic-assisted total knee arthroplasty results in decreased incidence of anterior femoral notching compared to posterior referenced instrumented total knee arthroplasty.

Periprosthetic fracture (PPF) is an uncommon but devastating complication after total knee arthroplasty (TKA). Anterior femoral notching (AFN) is one of a perioperative risk factor for PPF. The main purpose of this study was to compare between the rates of anterior femoral notching (AFN) and supracondylar periprosthetic femoral fracture (sPPF) of manual TKA and robotic arm-assisted TKA (RATKA). Meanwhile, blood loss, transfusion rates, inflammatory responses, complications, early clinical and radiological outcomes were also assessed. This retrospective study included 330 patients (133 RATKA and 197 manual TKA). Differences in risks of inflammatory, blood loss, complications (periprosthetic fracture and periprosthetic joint infection), pre-operative and post-operative distal lateral femoral angle (LDFA), distal femoral width (DFW), prosthesis-distal femoral width (PDFW) ratio, AFN, femoral component flexion angle (FCFA), peri-operative and post-operative functional outcomes between the RATKA and manual TKA groups were compared. The operation time and postoperative CRP level in the RATKA group was significantly longer and higher than that in the manual TKA group (p < .001). However, there was no significant difference in postoperative WBC level (p = .217), hemoglobin loss (p = .362), postoperative drainage (p = .836), and periprosthetic fracture (p = 1.000). There was no significant difference in LDFA (p > .05), DFW(p = .834), PDFW ratio (p = .089) and FCFA (p = .315) between the two groups, but the rate of AFN in the RATKA group was significantly lower than that in the manual TKA group (p < .05). There was no significant difference in ROM between the two groups on POD3, POD 90 and 1 year (p < .05), but the FJS-12 score in the RATKA group was higher than that in the manual TKA group on 1 year (p = .001). Robotic-assisted total knee arthroplasty can decrease the incidence of anterior femoral notching compared to posterior referenced instrumented total knee arthroplasty.

Precise Calibration of Femoral Component Rotation Using the Posterior Condylar Axis as a Reference during Image-free Robot-assisted Total Knee Arthroplasty: A Technical Note.

The use of image-free robotic systems for total knee arthroplasty (TKA) is gaining popularity. Although the surgical transepicondylar axis (sTEA) is considered the optimal femoral rotational reference during TKA, it is difficult to define intra-operatively. Conventional and image-free robot-assisted TKA (RA-TKA) therefore rely on the use of Whiteside's axis (WSA) or the posterior condylar axis (PCA) as surrogate references. The PCA is considered to be associated with less variability than the WSA. The authors present a simple technique to permit calibration of femoral component rotation (FCR) using the PCA as a reference for image-free robotic systems that do not permit this option. The image-free robotic systems used by the authors (Navio and CORI, Smith and Nephew, Memphis, TN, USA) permit calibration of FCR only when the perpendicular to WSA is used as a reference. When the PCA is selected as a reference, a fixed 3° of external rotation is set by the robot. The technique proposed by the authors involves the use of the former setting, followed by internal rotation of the perpendicular to the WSA to co-align it with the PCA. The planning menu subsequently permits virtual surgical planning using the PCA as the femoral rotational reference and permits adjustments in rotational positioning of the femoral component while displaying the effect of rotation on bony resection and vice versa in real time. In addition, coaligning the perpendicular to the anatomic trans-epicondylar axis (aTEA) displays the internal rotation of the PCA with respect to the aTEA. This information can be used for setting rotational boundaries with respect to the PCA while using various alternate alignment strategies, like functional alignment, since the relation between the aTEA and sTEA is less likely to be affected by dyplasia and wear when compared with the PCA or WSA. This simple technique permits optimally calibrated rotational positioning of the femoral component during image-free RA-TKA, using the PCA as a reference. It can be applied for optimizing surgery in knees with altered or outlier anatomy, as well as routinely, especially when alternate alignment strategies are used.

Short-term functional outcomes of robotic-assisted TKA are better with functional alignment compared to adjusted mechanical alignment.

Ligament balancing is essential to the functional outcome of total knee arthroplasty (TKA). The optimal method of alignment remains a controversial issue. The primary objective was to compare the clinical outcomes of TKA between functional and adjusted mechanical alignment techniques. The secondary objectives were to compare bone resection, robotic alignment, and radiological assessment. This was a retrospective case-control series comparing TKA performed with functional alignment (FA) and adjusted mechanical alignment (aMA). Sixty-four FA subjects were matched with 64 aMA controls. These two groups were matched for age, gender, body mass index (BMI), surgeon, and type of frontal deformity. Both surgical procedures were performed using the MAKO® haptic robotic system. Functional scores (Forgotten Joint Score (FJS), Knee Society Score (KSS), and Oxford Knee Score (OKS)) were measured at the final postoperative follow-up. A radiographic evaluation was performed at the same time. Mean FJS were respectively 63.4±25.1 [0-100] and 51.2±31.8 [0-100] in FA versus aMA group (p=0.034). Mean OKS were respectively 40.8±6.3 [21-48] and 34.9±11.8 [3-48] in FA versus aMA group (p=0.027). Mean KSS were respectively 184.9±17.0 [126-200] and 175.6±23.1 [102-200] in FA versus aMA group (p=0.02). The main residual symptom was "none" for 73.0% versus 57.8%, "instability" for 6.4% versus 21.9%, "Pain" for 19.1% versus 12.5%, and "effusion" for 1.6% and 7.8% respectively for FA and aMA group (p=0.016). There were 4 complications in the FA group versus 5 in the aMA group (p>0.999). Mean postoperative hip-knee-ankle (HKA) robotic assessment were respectively 177.3°±2.0 [172-180] and 178.2°±2.0 [173-180] for FA and aMA group (p=0.018). The median difference between HKA robotic and HKA radiological was -3.0° (IQR=3.0; p<0.001). With greater residual deformity and without release, functional alignment showed a statistically significantly better short-term clinical outcome than adjusted mechanical alignment. This difference may not be clinically significant.

The Effect of ERAS Concept-Guided Perioperative Care Intervention on Patients Undergoing Robot-Assisted Total Knee Arthroplasty

The Effect of ERAS Concept-Guided Perioperative Care Intervention on Patients Undergoing Robot-Assisted Total Knee Arthroplasty

Using Software to Implant Orthopaedic Hardware: Surgeon Intraoperative Confidence Increased with Latest Technological Updates.

Robotic-assisted total knee arthroplasty (TKA) has been associated with improved accuracy and precision of implant placement, protection of soft tissue, and improved patient-reported postoperative outcomes when compared to manual TKA techniques. Previous studies have highlighted the importance of surgical confidence throughout the learning curve when adopting robotic-assisted platforms. The purpose of this study was to evaluate the confidence and efficiencies of surgeons when utilizing computed tomography (CT)-based robotic TKA technology. A cross-sectional, questionnaire-based study was conducted with 20 arthroplasty-trained surgeons with prior experience in both manual TKA and robotic-assisted TKA techniques. The surgeons completed an initial learning period, with new software, during various stages of their experience. The new TKA software upgrade builds on the prior software version with new features. A Net Promoter Score (NPS), the measurement of a respondent's likelihood to recommend a product or service to others, was used during the analysis of survey questions. A NPS over 50 indicates a positive score. When compared to manual TKA techniques, 95% of surgeons reported that their overall intraoperative confidence increased with the new software upgrade for CT-based robotic technology and had an average rating of 8.9 out of 10 for their intraoperative confidence with the new software upgrade. Additionally, 100% of surgeons reported that they were more confident when performing intraoperative implant adjustments with the new software upgrade when compared to manual TKA. Surgeons determined that the overall use of the new software upgrade was intuitive (8.4 of 10 average rating) and were satisfied with the overall use of the new software upgrade (9 of 10 average rating). Also, surgeons reported that they would recommend the new software upgrade for CT-based robotic technology to colleagues (NPS of 85), as well as being used as a research tool (NPS of 85) or for a training and education tool in a fellowship program (NPS of 90). As new technology continues to enter the field of orthopedics, it is important to ensure upgrades and advancements continue to serve surgeons and provide efficiencies in the operating room. For established robotic surgeons, the new robotic technology assessed in this study provided increased confidence when compared to manual TKA. Based on these results, the new software upgrade demonstrated value during various stages of a TKA procedure and is highly recommended for use by others in the field of orthopedics.

Robotic-Assisted Knee Arthroplasty: Insights and Implications From Current Literature.

Robotic-assisted knee arthroplasty has emerged as a promising development, aiming to enhance surgical precision and patient outcomes. This literature review examines the clinical efficacy, cost implications, environmental impact, and potential of telesurgery in robotic-assisted total knee arthroplasty (RATKA) and robotic-assisted unicompartmental knee arthroplasty (RAUKA) relative to conventional techniques. A thorough literature search was conducted across medical databases. Clinical and radiological outcomes of RATKA and RAUKA were extracted and analyzed. Direct costs, operating time, surgeon learning curve, environmental implications, and the futuristic concept of telesurgery were also considered. Subjective patient assessments such as WOMAC, Oxford Knee Score, and SF-36, alongside objective measures like HSS score and KSS, were commonly used. Radiological parameters like hip-knee-ankle (HKA) and femorotibial angle provided insights into post-operative alignment. Evidence indicated sporadic high-level design studies, often with limited samples. Cost remains a major constraint with robotic systems, though high-volume cases might offset expenses. Environmental assessments revealed robotic surgeries generate a higher carbon footprint. Telesurgery, an evolving field, could transcend geographical boundaries but is not without challenges, including high costs, latency issues, and cyber threats. While robotic-assisted surgeries may hold promise in the future, substantial barriers, including acquisition costs, potential surgeon deskilling, and environmental concerns, need addressing. Greater robot utilization may drive costs down with more competitors entering the market. Continued research, especially multi-center RCTs, is pivotal to solidifying the role of robotic systems in knee arthroplasty.

CORR Insights®: Robotic-assisted TKA is Not Associated With Decreased Odds of Early Revision: An Analysis of the American Joint Replacement Registry.

CORR Insights®: Robotic-assisted TKA is Not Associated With Decreased Odds of Early Revision: An Analysis of the American Joint Replacement Registry.