Lizcano, Juan D

Background Robotic-assisted TKA may allow for more reproducible balancing and implant positioning. However, few RCTs have directly compared modern robotic-assisted TKA to conventional TKA. Questions/purposes (1) Do patients undergoing robotic-assisted TKA perform better on the Timed Up and Go (TUG) test and Stair Climb test (SCT) than patients undergoing conventional TKA at 1 and 6 months after surgery? (2) Do patients undergoing robotic-assisted TKA demonstrate better patient-reported outcomes, including Knee Injury and Osteoarthritis Outcome Score (KOOS), EQ-5D, and VAS scores, than patients undergoing conventional TKA at 1 and 6 months after surgery? (3) Do patients undergoing robotic-assisted TKA demonstrate better radiographic alignment and position than patients undergoing conventional TKA? Methods In this double-blind RCT, 60 patients were randomized to robotic-assisted TKA (n = 30) or conventional TKA (n = 30) without the use of a tensioning device. All care was otherwise standardized, using mechanical alignment guides. The primary outcome measures were the TUG and SCT tests; results were collected by a blinded observer at 6 months postoperatively. These time points were chosen based on the maximal early improvement in patient-reported outcomes and bimodal distribution of the TUG and SCT tests, worsening in the immediate postoperative period, and improving within the first 6 months. Secondary outcome measures were KOOS, EQ-5D, and VAS scores; radiographic measurements; and operative time. Standard bivariate statistical analysis was conducted. The mean ± SD age of the cohort was 66 ± 7 years, with no differences between groups (p = 0.21). Ninety-three percent (28 of 30) of patients in the robotic-assisted group were White versus 97% (29 of 30) in the conventional TKA group (p > 0.99). Women made up 57% (17) of the robotic-assisted cohort and 60% (18) of the conventional TKA cohort. No differences were noted between the robotic-assisted and conventional TKA groups in BMI, Charlson comorbidity index, or American Society of Anesthesiologists (ASA) classification. Results Patients undergoing robotic-assisted TKA did not perform better than those who underwent conventional TKA on the TUG (11 versus 11 seconds; p = 0.88) or SCT (15 versus 15 seconds; p = 0.93) tests. Patients undergoing robotic-assisted TKA did not demonstrate better mean ± SD scores on the KOOS pain subscale than patients undergoing conventional TKA (86 ± 14 versus 80 ± 17; p = 0.15). Patients undergoing robotic-assisted TKA did not demonstrate better radiographic alignment and position than patients undergoing conventional TKA based on hip-knee-ankle angle (178° versus 178°; p = 0.89). No differences between the two groups were noted at the 1-month follow-up in TUG and SCT test results. Conclusion In this study, patients who underwent robotically assisted TKA did no better in terms of function, patient-reported outcomes, or radiographic measures than did patients who underwent conventional TKA. Until or unless future studies demonstrate benefits of robotically assisted TKA that are large enough for patients to perceive, we recommend against its use. Level of Evidence Level I, therapeutic study.

AimThis study aimed to evaluate the impact of intraoperative direct sonication on the yield of traditional culture and the time to positivity (TTP) of cultures obtained for periprosthetic joint infection (PJI), thereby assessing its potential to improve diagnostic efficiency and reduce contamination risk.MethodA prospective cohort study was conducted at a tertiary care center, involving 190 patients undergoing revision surgery for PJI from August 2021 to January 2024. Patients were included based on the 2018 International Consensus Meeting definition of PJI. The study utilized a novel sonication protocol, which involved direct intraoperative sonication of the implant and tissue, followed by incubation in a BACT/ALERT 3D system. The primary outcomes measured were the number and percentage of positive culture samples, identified microorganisms, and the TTP of each culture. Statistical analysis was performed using R software, with various tests applied to assess the significance of findings.ResultsThe study included 510 positive cultures from 190 patients, demonstrating that sonication significantly improved the positivity rate for both tissue and prosthesis specimens (p < 0.05). The median TTP for all samples was 3.13 days, with sonicated samples showing a significantly shorter TTP compared to non-sonicated samples (p < 0.05). Specifically, the shortest median TTP was observed in prosthesis post-sonication samples. Furthermore, the study found that Gram-positive organisms had a shorter TTP than gram-negative organisms, and specific microorganisms like Staphylococcus aureus and MRSE showed the fastest TTP. The analysis also revealed higher positivity rates in chronic PJIs compared to acute PJIs for sonicated tissue samples.ConclusionsThe study demonstrates that intraoperative direct sonication combined with the BACT/ALERT 3D system can significantly enhance the diagnostic yield of cultures and reduce the TTP for common PJI pathogens. This novel technique not only improves pathogen detection, facilitating the tailoring of antibiotic therapy, but also potentially reduces the risk of contamination associated with sonication. These findings suggest that direct intraoperative sonication could be a valuable addition to the current diagnostic protocols for PJI, contributing to more effective management and treatment of this complex condition. Further research is necessary to explore the clinical significance of TTP and its correlation with patient outcomes in PJI.