[Effectiveness comparison of robot-assisted and traditional freehand technology in treatment of atlantoaxial dislocation].

Objective: To compare the effectiveness of robot-assisted and traditional freehand screw placement in the treatment of atlantoaxial dislocation. Methods: The clinical data of 55 patients with atlantoaxial dislocation who met the selection criteria between January 2021 and January 2024 were retrospectively analyzed. According to different screw placement methods, they were divided into the traditional group (using the traditional freedhand screw placement, 31 cases) and the robot group (using the Mazor X robot-assisted screw placement, 24 cases). There was no significant difference in gender, age, body mass index, etiology, and preoperative visual analogue scale (VAS) score, cervical spine Japanese Orthopaedic Association (JOA) score between the two groups ( P>0.05). The operation time, intraoperative blood loss, operation cost, and intraoperative complications were recorded and compared between the two groups. The VAS score and cervical spine JOA score were used to evaluate the improvement of pain and cervical spinal cord function before operation and at 1 month after operation. CT examination was performed at 3 days after operation, and the accuracy of screw placement was evaluated according to Neo grading criteria. Results: All the 55 patients successfully completed the operation. The operation time, intraoperative blood loss, and operation cost in the robot group were significantly higher than those in the traditional group ( P<0.05). A total of 220 C 1 and C 2 pedicle screws were inserted in the two groups, and 94 were inserted in the robot group, with an accuracy rate of 95.7%, among them, 2 were inserted by traditional freehand screw placement due to bleeding caused by intraoperative slip. And 126 pedicle screws were inserted in the traditional group, with an accuracy rate of 87.3%, which was significantly lower than that in the robot group ( P<0.05). There were 1 case of venous plexus injury in the robot group and 3 cases in the traditional group, which improved after pressure hemostasis treatment. No other intraoperative complication such as vertebral artery injury or spinal cord injury occurred in both groups. All patients were followed up 4-16 months with an average of 6.6 months, and there was no significant difference in the follow-up time between the two groups ( P>0.05). Postoperative neck pain significantly relieved in both groups, and neurological symptoms relieved to varying degrees. The VAS score and cervicle spine JOA score of both groups significantly improved at 1 month after operation when compared with preoperative scores ( P<0.05), and there was no significant difference in the score change between the two groups ( P>0.05). Conclusion: In the treatment of atlantoaxial dislocation, the accuracy of robot-assisted screw placement is superior to the traditional freedhand screw placement.

Comparison of the efficacies of TINAVI robot-assisted surgery and conventional open surgery for Levine-Edward type IIA (postreduction) hangman fractures.

The objective was to compare the clinical efficacy of percutaneous pedicle screw internal fixation with the aid of the TINAVI orthopaedic surgery robot with that of traditional open surgery for Levine-Edward type IIA (postreduction) hangman fractures and to evaluate the safety and efficacy of the TINAVI robot-assisted orthopaedic surgery procedure. The clinical data of 60 patients with Levine-Edward type IIA (postreduction) hangman fractures treated surgically from June 2015 to February 2022 were analysed retrospectively. Among these patients, 25 were treated with percutaneous pedicle screw fixation under TINAVI (the robot group), and 35 were treated with pedicle screw implantation assisted by a conventional C-arm X-ray machine (the traditional operation group). The pedicle screw placement grade was evaluated according to the Rampersaud scale. The correct rate of pedicle screw placement was calculated. The invasion of adjacent facet joints, VAS score (Visual Analogue Scale), NDI score (Neck Disability Index), SF-36 score (36-Item Short-Form Health Survey questionnaire), EQ-5D score (EuroQol-5 dimensions questionnaire) and operation-related data were recorded, and patients were followed up. All patients were followed up for an average of 15.0 ± 3.4 months. The accuracy of screw placement in the robot group was higher than that in the traditional operation group, while the rates of intraoperative blood loss and invasion of the facet joint were lower and the incision length and length of hospital stay were shorter. On the 3rd day after the operation, the VAS score in the robot group was significantly higher than that in the traditional operation group, but there was no significant difference in the NDI score. On the 3rd day after the operation, the SF-36 and EQ-5 questionnaire scores of the robot group were better than those of the traditional operation group. No complications occurred in any of the patients. Postoperative cervical X-ray showed that the cervical vertebra was stable, and there was no fracture, angle or displacement. Postoperative CT showed that all fractures healed, and the average healing time was 3.4 months. The treatment of Levine-Edward IIA (postrepositioning) hangman fractures with percutaneous pedicle fixation assisted by the TINAVI orthopaedic surgery robot can significantly improve screw placement accuracy with a low rate of invasion of the adjacent facet joint, a short operation time, a low bleeding rate, and high patient satisfaction. Although there are still many disadvantages, it still has good prospects for application.

High-Strength Cell Sheets and Vigorous Hydrogels from Mesenchymal Stem Cells Derived from Human Embryonic Stem Cells.

Natural cell derivates, including cell sheets (CSs) and matrix gels, have opened new opportunities to probe questions in tissue engineering and regenerative medicine. However, the potential of CSs and hydrogels generated by current protocols is still limited by the challenges of heterogeneity and weak mechanical properties. Here, we developed a 21 day long-term serum-free culture system for human embryonic stem cell (hESC)-derived immunity-and-matrix-regulatory cells (IMRCs). The CSs formed with IMRCs (IMRC-CSs) have a much greater secretion capacity for the extracellular matrix (ECM) and stronger mechanical properties than umbilical cord-derived MSCs, with a ten thousand-fold increase in elastin, a higher elastic modulus of 1500 kPa, a thicker structure of 20.59 µm, and a higher fiber count per square millimeter. The IMRC-CSs could promote corneal chemical injury repair and could be turned into injectable temperature-sensitive hydrogels for uterine adhesion repair via a decellularization process. In summary, we have established a high-strength CS platform using human pluripotent stem cells for the first time, providing a facile and scalable engineering approach for regenerative medicine.

Orthopedic Robot-Assisted Femoral Neck System in the Treatment of Femoral Neck Fracture.

Cannulated screw fixation is the main therapy for femoral neck fractures, especially in young patients. The traditional surgical procedure uses C-arm fluoroscopy to place the screw freehand and requires several guide wire adjustments, which increases the operation time and radiation exposure. Repeated drilling can also cause damage to the blood supply and bone quality of the femoral neck, which can be followed by complications such as screw loosening, nonunion, and femoral head necrosis. In order to make fixation more precise and reduce the incidence of complications, our team applied robot-assisted orthopedic surgery for screw placement using the femoral neck system to modify the traditional procedure. This protocol introduces how to import a patient's X-ray information into the system, how to perform screw path planning in software, and how the robotic arm assists in screw placement. Using this method, the surgeons can place the screw successfully the first time, improve the accuracy of the procedure, and avoid radiation exposure. The whole protocol includes the diagnosis of femoral neck fracture; the collection of intraoperative X-ray images; screw path planning in the software; precise placement of the screw under the assistance of the robotic arm by the surgeon; and verification of the implant placement.

Spine Surgical Robotics: Current Status and Recent Clinical Applications.

With the development of artificial intelligence and the further deepening of medical-engineering integration, spine surgical robot-assisted (RA) technique has made significant progress and its applicability in clinical practice is constantly expanding in recent years. In this review, we have systematically summarized the majority of literature related to spine surgical robots in the past decade, and not only classified robots accordingly, but also summarized the latest research progress in RA technique for screw placement such as cervical, thoracic, and lumbar pedicle screws, cortical bone trajectory screws, cervical lateral mass screws, and S2 sacroiliac screws; guiding targeted puncture and placement of endoscope via the intervertebral foramen; complete resection of spinal tumor tissue; and decompressive laminectomy. In addition, this report also provides a detailed evaluation of RA technique's advantages and disadvantages, and clarifies the accuracy, safety, and practicality of RA technique. We consider that this review can help clinical physicians further understand and familiarize the current clinical application status of spine surgical robots, thereby promoting the continuous improvement and popularization of RA technique, and ultimately benefiting numerous patients.

Reconstruction of functional uterine tissues through recellularizing the decellularized rat uterine scaffolds by MSCs in vivo and in vitro.

Infertile people who suffered from loss of uterine structures and/or functions can be treated through gestational surrogacy or uterus transplantation, which remains challenging due to the ethical and social issues, the lack of donor organs as well as technical and safety risks. One promising solution is to regenerate and reconstruct a bioartificial uterus for transplantation through the engineering of uterine architecture and appropriate cellular constituents. Here, we developed a well-defined system to regenerate a functional rat uterine through recellularization of the decellularized uterine matrix (DUM) patches reseeded with human mesenchymal stem cells (hMSCs). Engraftment of the recellularized DUMs on the partially excised uteri yielded a functional rat uterus with a pregnancy rate and number of fetuses per uterine horn comparable to that of the control group with an intact uterus. Particularly, the recellularized DUMs enhanced the regeneration of traumatic uterine in vivo because of MSC regulation. The established system here will shed light on the treatment of uterine infertility with heterogeneous DUMs/cell resources through tissue engineering in the future.

Modulating the cellular microenvironment with disulfide-containing nanoparticles as an auxiliary cancer treatment strategy.

Stimuli-responsive drug release nanoparticles are of particular interest due to their enhanced effects and reduced systemic toxicities in the area of cancer therapeutics. The effect of these nanoparticles on the cellular microenvironment has not yet been clearly defined. In this context, redox-responsive nanoparticles were synthesized with disulfide-containing linkages. These nanoparticles depleted the cellular GSH level and modulated the cellular redox microenvironment to more oxidizing conditions. The resulting drug-encapsulated nanoparticles showed improved cytotoxicity, apoptosis, and invasion inhibition of metastatic cancer cells. Moreover, these improvements had a direct correlation with the cellular redox status modulated by nanoparticles. The present study provides a new strategy for designing redox-responsive drug carriers to improve the sensitivity of cells to anticancer drugs and enhance the therapeutic efficacy in metastatic cancer.

Amphiphilic p-sulfonatocalix[4]arene as "drug chaperone" for escorting anticancer drugs.

Supramolecularly constructing multifunctional platform for drug delivery is a challenging task. In this work, we propose a novel supramolecular strategy "drug chaperone", in which macrocyclic amphiphiles directly coassemble with cationic drugs into a multifunctional platform and its surface is further decorated with targeting ligands through host-guest recognition. The coassembling and hierarchical decoration processes were monitored by optical transmittance measurements, and the size and morphology of amphiphilic coassemblies were identified by dynamic light scattering and high-resolution transmission electron microscopy. In cell experiments to validate the drug chaperone strategy, the anticancer activities of free drugs were pronouncedly improved by coassembling with amphiphilic chaperone and further functionalization with targeting ligand.