BACKGROUND: Arsenic trioxide (ATO) is indicated as a broad-spectrum medicine for a variety of diseases, including cancer and cardiac disease. While the role of ATO in hepatic ischemia/reperfusion injury (HIRI) has not been reported. Thus, the purpose of this study was to identify the effects of ATO on HIRI. METHODS: In the present study, we established a 70% hepatic warm I/R injury and partial hepatectomy (30% resection) animal models in vivo and hepatocytes anoxia/reoxygenation (A/R) models in vitro with ATO pretreatment and further assessed liver function by histopathologic changes, enzyme-linked immunosorbent assay, cell counting kit-8, and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay. Small interfering RNA (siRNA) for extracellular signal-regulated kinase (ERK) 1/2 was transfected to evaluate the role of ERK1/2 pathway during HIRI, followed by ATO pretreatment. The dynamic process of autophagic flux and numbers of autophagosomes were detected by green fluorescent protein-monomeric red fluorescent protein-LC3 (GFP-mRFP-LC3) staining and transmission electron microscopy. RESULTS: A low dose of ATO (0.75 μmol/L in vitro and 1 mg/kg in vivo ) significantly reduced tissue necrosis, inflammatory infiltration, and hepatocyte apoptosis during the process of hepatic I/R. Meanwhile, ATO obviously promoted the ability of cell proliferation and liver regeneration. Mechanistically, in vitro  studies have shown that nontoxic concentrations of ATO can activate both ERK and phosphoinositide 3-kinase-serine/threonine kinase (PI3K-AKT) pathways and further induce autophagy. The hepatoprotective mechanism of ATO, at least in part, relies on the effects of ATO on the activation of autophagy, which is ERK-dependent. CONCLUSION Low, non-toxic doses of ATO can activate ERK/PI3K-AKT pathways and induce ERK-dependent autophagy in hepatocytes, protecting liver against I/R injury and accelerating hepatocyte regeneration after partial hepatectomy.
Animals ; Arsenic Trioxide ; Autophagy/physiology* ; Reperfusion Injury/prevention & control* ; Mice ; Male ; Proto-Oncogene Proteins c-akt/physiology* ; Arsenicals/therapeutic use* ; Oxides/therapeutic use* ; Liver/metabolism* ; Extracellular Signal-Regulated MAP Kinases/metabolism* ; Mice, Inbred C57BL

Objective:To compare the efficacy of robot system-assisted versus freehand screw revision for ankylosing spondylitis (AS) with lower cervical fractures.Methods:A multicenter retrospective cohort study was conducted to analyze the clinical data of 57 patients with AS combined with lower cervical fractures admitted to Honghui Hospital Affiliated to Xi'an Jiaotong University School of Medicine, Henan Provincial People's Hospital, Zhengzhou Orthopedic Hospital, and Qilu Hospital of Shandong University, including 46 males and 11 females, aged 38-77 years [(65.4±9.5)years]. Injury segments involved C 3 in 7 patients, C 4 in 13, C 5 in 25, C 6 in 10, and C 7 in 2. All the patients underwent revision surgery, among whom, 22 patients were treated with robot system-assisted cervical pedicle screw placement (robot nailing group, with 190 screws), and 35 with freehand cervical pedicle screw placement (freehand nailing group, with 300 screws). The operative duration, intraoperative bleeding volume, frequency of intraoperative fluoroscopy, incision length, and length of hospital stay of the two groups were compared; the time of single nscrew insertion, the number of single nail revisions, the distance between screws and the anterior cortex, the accuracy of screw placement of grade 0 and grade 0+1 were recorded in the two groups. The visual analogue scale (VAS), Japanese Orthopedic Society (JOA) score, neck dysfunction index (NDI), American Spine Injury Association (ASIA) classification before operation, at 3 days, 3 months after operation and at the last follow-up were compared between the two groups. The complication rate was also noted. Results:All the patients were followed up for 12-16 months [(14.3±2.1)months]. The operative duration, intraoperative bleeding volume, and frequency of intraoperative fluoroscopy were (186.4±12.9)minutes, (486.1±68.6)ml, and (3.4±1.3)times in the robot nailing group, which were shorter or less than (206.7±14.4)minutes, (660.3±45.2)ml, and (13.5±3.6)times in the freehand nailing group ( P<0.01). The incision length was (9.4±2.4)cm in the robot nailing group, longer than (5.6±1.2)cm in the freehand nailing group ( P<0.01), and the length of hospital stay was (3.7±0.4)days, shorter than (4.4±1.4)days in the freehand nailing group ( P<0.01). The length of single nail insertion, the number of single nail revision, and the distance between the screws and the front cortex were (6.5±0.4)minutes, (1.1±0.1)times, and (3.5±1.3)mm in the robot nailing group, which were shorter or less than (11.6±0.2)minutes, (1.5±0.2)times, and (12.4±4.7)mm in the freehand nailing group ( P<0.01). The accuracy of the screw placement in the robot nailing group was 90.0% (171/190) and 95.8% (182/190) with level 0 and 0+1 screws, better than 80.0% (240/300) and 89.0% (267/300) in the freehand nailing group ( P<0.05). There was no significant difference in VAS, JOA score, NDI, or ASIA grading between the two groups before operation ( P>0.05). The VAS, JOA, and NDI scores at 3 days after operation were (3.1±0.6)points, (12.1±1.2)points, and (15.6±2.9)points, respectively in the robot nailing group, which were better than (5.0±1.4)points, (11.3±1.1)points and (22.5±3.7)points, respectively in the freehand nailing group ( P<0.05). No statistically significant difference was observed in the ASIA grade between the two groups at 3 days after operation ( P>0.05). There were no significant differences in VAS, JOA, NDI scores, or ASIA grading between the two groups at 3 months after operation and at the last follow-up ( P>0.05). Compared with those before operation, the VAS, JOA, NDI scores, and ASIA grading were significantly improved at 3 days, 3 months after operation and at the last follow-up in the two groups, which were further improved with the passage of time. Two patients in the robot nailing group had pneumonia, with a complication rate of 9% (2/22), while 2 patients in the freehand nailing group had dural sac rupture and cerebrospinal fluid leakage and 3 had lung infection after operation, with a complication rate of 14% (5/35) ( P<0.05). Conclusion:Compared with freehand nailing, the robot system-assisted nailing revision for AS with lower cervical fracture has more advantages in terms of the operative duration, length of hospital stay, intraoperative bleeding volume, frequency of intraoperative fluoroscopy nailing speed and accuracy, screw holding force, early pain relief, function restoration, and complication rate, despite longer surgical incision.

Objective:To compare the clinical efficacy of navigation system and orthopedic robot-assisted nail placement in the treatment of lower cervical fracture and dislocation.Methods:A retrospective cohort study was conducted to analyze the clinical data of 49 patients with fracture and dislocation of the lower cervical spine who were admitted to Honghui Hospital, Xi′an Jiaotong University School of Medicine from May 2021 to October 2022, including 38 males and 11 females, aged 29-61 years [(39.3±7.3)years]. Injury segments involved C 3 in 12 patients, C 4 in 11, C 5 in 8, C 6 in 9 and C 7 in 9. Twenty-one patients were treated with S8 navigation system (navigation group, 84 screws), and 28 with TINAVI orthopedic robot (robot group, 112 screws). The two groups were compared in terms of the total surgical duration, single screw placement time, total screw placement time, distance between the screw and the anterior cortex, incision length, intraoperative radiation dose, intraoperative blood loss and length of hospital stay. The height of intervertebral space, Cobb angle, sliding distance between vertebral bodies and American Spinal Injury Association (ASIA) grade were assessed before surgery and at 3 days after surgery. Visual analogue scale (VAS), Japanese Orthopedic Association (JOA) score and neck dysfunction index (NDI) before surgery, at 3 days, 3 months after surgery and at the last follow-up were compared. The accuracy of screw placement, intraoperative invasion rate of adjacent facet joints and rate of postoperative complications (infection, screw loosening, etc.) were evaluated. Results:All the patients were followed up for 12-16 months [(13.6±1.9)months]. In the navigation group, the total surgical duration, distance from the screw to the anterior cortex and the intraoperative radiation dose were (236.2±30.6)minutes, (2.0±0.2)mm and (374.3±90.3)mGy respectively, which were significantly shorter or less than those in the robot group [(278.4±20.7)minutes, (10.6±2.9)mm and (448.4±77.9)mGy] ( P<0.01). The single screw placement time, total screw placement time, incision length and intraoperative blood loss were (3.5±0.4)minutes, (23.9±0.5)minutes, (9.1±2.4)cm and (422.2±30.4)ml respectively, which were significantly longer or more than those in the robot group [(2.6±0.2)minutes, (17.9±0.7)minutes, (6.6±2.6)cm and (360.3±56.3)ml] ( P<0.01). There was no significant difference in the length of hospital stay between the two groups ( P>0.05). No significant differences were observed in the height of the intervertebral space, Cobb angle, sliding distance between the vertebral bodies and ASIA grade between the two groups ( P>0.05). At 3 days after surgery, the height of intervertebral space, Cobb angle, sliding distance between vertebral bodies and ASIA grade in both groups were significantly improved when compared with those before surgery ( P<0.05 or 0.01). There were no significant differences in VAS, JOA scores or NDI between the two groups before surgery, at 3 days, 3 months after surgery and at the last follow-up ( P>0.05). The VAS, JOA scores and NDI in both groups were gradually improved at 3 days, 3 months and at the last follow-up after surgery when compared with those before surgery ( P<0.05). There was no significant difference in the accuracy of screw placement of levels 0 and 0+1 between the two groups ( P>0.05). No significant difference in the intraoperative invasion rate of adjacent facet joints between the two groups was found ( P>0.05). There were no serious complications such as infection or screw loosening after surgery in both groups. Conclusions:For lower cervical fracture and dislocation, although there are more advantages in total surgical duration, screw holding force and radiation control regarding the navigation system, and more outstanding performance in screw placement efficiency, incision length and intraoperative blood loss regarding the orthopedic robot, both of them can effectively rebuild the cervical structure, improve neurological function, relieve postoperative pain, improve screw placement accuracy and reduce facet joint injury and serious complications. Selection of the best auxiliary screw placement system should comprehensively consider patients′ conditions and the experience of the surgical team.

Objective:To investigate the clinical characteristics of children with Chikungunya fever.Methods:This retrospective cohort study analyzed clinical data of 91 children with Chikungunya fever at the Department of Pediatrics, Foshan women and Children Hospital between July 2025 and August 2025. The patients were divided into four groups based on onset-age: 0-<1 year, 1-<3 years, 3-<6 years, and 6-14 years. One-way ANOVA and chi-square tests were used to compare the clinical features of children with Chikungunya fever at different ages.Results:Among the 91 children with chikungunya fever, 55 were male and 36 were female, with an onset age of 6 (2, 11) years, age groups comprised 0-<1 year (10 cases), 1-<3 years (13 cases), 3-<6 years (17 cases) and 6-14 years (51 cases). Fever occurred in 87 cases (96%), with 50 cases (57%) had high fever. Skin rash was observed in 89 cases (98%), and 60 cases (67%) had a generalized rash. Joint pain was reported in 57 cases (63%), among which 35 cases (61%) had pain in two or more locations, with the knee involved in 21 cases (37%), the ankle in 15 cases (26%), and the wrist in 6 cases (11%).The knee was the most commonly affected joint 21 cases (37%), followed by the ankle 15 cases (26%) and wrist 6 cases (10%). Joint ultrasound was performed in 31 cases (34%), all showed joint effusion, including 8 cases (26%) without complaints of joint pain. The incidence of high fever was significantly lower in the 3-<6 years and 6-14 years groups compared to the 0-<1 year group (both P<0.05). The 6-14 years group also had a lower incidence of high fever than the 1-<3 years group ( P<0.05). The 1-<3 years group had longer duration of fever than the 3-<6 years and 6-14 years groups (both P<0.05). The incidence of joint pain was higher in the 3-<6 years and 6-14 years groups compared to the 1-<3 years group (both P<0.05), and higher in the 6-14 years group than in the 3-<6 years group ( P=0.007). Among all 91 children, 22 cases (24%) had abnormal liver function, 49 cases (54%) showed elevated lactate dehydrogenase (LDH), and 2 cases (2%) had elevated creatine kinase. The proportions of elevated aspartate aminotransferase (AST) and LDH were higher in the 0-<1 year and 1-<3 years groups compared to the 3-<6 years and 6-14 years groups (all P<0.05). Conclusions:The clinical characteristics of children with Chikungunya fever vary among children of different ages. Children in the 0-<3 years are more prone to high fever with longer duration and generalized maculopapular rash, while the children in the 6-14 years have have a higher proportion of joint pain, and joint ultrasound revealed effusion in all examined children. AST and LDH levels are elevated in the 0-<3 years groups.

Objective To analyze the hotspots and development trends of the economic burden of acute ischemic stroke,and to provide a reference for researchers in China to conduct related studies.Methods Web of Science Core Collection database was searched to collect relevant reviews or articles on the economic burden of acute ischemic stroke from January 1994 to December 2023.CiteSpace 6.1.R6 software was used to visualize the authors,countries/regions,research institutions,keywords,and co-cited references.Results A total of 1,162 articles were include.The United States was the country with highest number of publications and centrality.China ranked the second in publication volume,but its centrality ranking was relatively low.Among the top 10 institutions in terms of publication volume,6 were from the United States,and Capital Medical University was the only Chinese institution listed.The cost-effectiveness analysis of treatment plans,scientific management method,and the cost-effectiveness analysis of treatment plans were the main research topics.The past three years had focused primarily on the cost-effectiveness analysis of treatment plans.Conclusion The study of the economic burden of acute ischemic stroke has advanced rapidly in recent years,but there is still a significant gap between China and developed western countries such as the United States.Chinese researchers should research current hotspots,while also addressing the early foundation studies of these hotspots,providing beneficial conditions for conducting hotspot research.

Objective To screen for differentially expressed apoptosis-related circular RNAs(circRNAs)in osteoblasts from steroid-induced osteonecrosis of the femoral head(SONFH)and to investigate their roles and mechanisms in osteoblast apoptosis.Methods MC3T3-E1 cells were cultured and divided into two groups:Control and DEX-treated.Western blot analysis was employed to evaluate the expression levels of BCL2-Associated X protein(Bax)and B-cell lymphoma 2(Bcl-2).Cell apoptosis was assessed using TUNEL staining and flow cytometry.RNA was extracted from both normal and DEX-treated MC3T3-E1 cells,followed by RNA-seq to identify differen-tially expressed circular RNAs(circRNAs).The functions and pathways of these circRNAs were analyzed using Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG).The differentially expressed mmu_circ_0000818 was selected for further verification at the cellular level.Its chromosomal location and conservation were examined using the UCSC Genome Browser Gateway and circBase.Overexpression plasmids and small interfering RNAs(siRNAs)targeting mmu_circ_0000818 were constructed and transfected into the cells.Subsequently,apop-tosis in MC3T3-E1 cells from each group was evaluated by flow cytometry.Results Compared with the control group,the apoptosis rate of MC3T3-E1 cells was significantly increased in the DEX group(P<0.01).Differen-tially expressed circRNAs were identified based on log2foldchange(≥2)and P value(P<0.05).Relative to the control group,there were 234 differentially expressed circRNAs in the DEX group,including 138 up-regulated and 96 down-regulated circRNAs.GO and KEGG enrichment analyses of the target genes of these differentially expressed circRNAs revealed significant associations with apoptosis and the PI3K-Akt signaling pathway.qRT-PCR results demonstrated that the expression level of mmu_circ_0000818 was markedly higher in the DEX group com-pared to the control group(P<0.01).Analysis using the UCSC Genome Browser and CircBase indicated that mmu_circ_0000818,located at chromosome 17:78712463-78715086,is formed by the cyclization of exons 6-7 of the Crim1 gene and exhibits high conservation across species.Flow cytometry results indicated that knockdown of mmu_circ_0000818 attenuated DEX-induced apoptosis in MC3T3-E1 cells,while overexpression of mmu_circ_0000818 exacerbated apoptosis.Conclusions CircRNA mmu_circ_0000818 was significantly upregulated in DEX-treated MC3T3-E1 cells,and its downregulation mitigated DEX-induced apoptosis.Consequently,mmu_circ_0000818 may represent a promising therapeutic target for the prevention and treatment of SONFH.

Objective To analyze the hotspots and development trends of the economic burden of acute ischemic stroke,and to provide a reference for researchers in China to conduct related studies.Methods Web of Science Core Collection database was searched to collect relevant reviews or articles on the economic burden of acute ischemic stroke from January 1994 to December 2023.CiteSpace 6.1.R6 software was used to visualize the authors,countries/regions,research institutions,keywords,and co-cited references.Results A total of 1,162 articles were include.The United States was the country with highest number of publications and centrality.China ranked the second in publication volume,but its centrality ranking was relatively low.Among the top 10 institutions in terms of publication volume,6 were from the United States,and Capital Medical University was the only Chinese institution listed.The cost-effectiveness analysis of treatment plans,scientific management method,and the cost-effectiveness analysis of treatment plans were the main research topics.The past three years had focused primarily on the cost-effectiveness analysis of treatment plans.Conclusion The study of the economic burden of acute ischemic stroke has advanced rapidly in recent years,but there is still a significant gap between China and developed western countries such as the United States.Chinese researchers should research current hotspots,while also addressing the early foundation studies of these hotspots,providing beneficial conditions for conducting hotspot research.

Objective To screen for differentially expressed apoptosis-related circular RNAs(circRNAs)in osteoblasts from steroid-induced osteonecrosis of the femoral head(SONFH)and to investigate their roles and mechanisms in osteoblast apoptosis.Methods MC3T3-E1 cells were cultured and divided into two groups:Control and DEX-treated.Western blot analysis was employed to evaluate the expression levels of BCL2-Associated X protein(Bax)and B-cell lymphoma 2(Bcl-2).Cell apoptosis was assessed using TUNEL staining and flow cytometry.RNA was extracted from both normal and DEX-treated MC3T3-E1 cells,followed by RNA-seq to identify differen-tially expressed circular RNAs(circRNAs).The functions and pathways of these circRNAs were analyzed using Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG).The differentially expressed mmu_circ_0000818 was selected for further verification at the cellular level.Its chromosomal location and conservation were examined using the UCSC Genome Browser Gateway and circBase.Overexpression plasmids and small interfering RNAs(siRNAs)targeting mmu_circ_0000818 were constructed and transfected into the cells.Subsequently,apop-tosis in MC3T3-E1 cells from each group was evaluated by flow cytometry.Results Compared with the control group,the apoptosis rate of MC3T3-E1 cells was significantly increased in the DEX group(P<0.01).Differen-tially expressed circRNAs were identified based on log2foldchange(≥2)and P value(P<0.05).Relative to the control group,there were 234 differentially expressed circRNAs in the DEX group,including 138 up-regulated and 96 down-regulated circRNAs.GO and KEGG enrichment analyses of the target genes of these differentially expressed circRNAs revealed significant associations with apoptosis and the PI3K-Akt signaling pathway.qRT-PCR results demonstrated that the expression level of mmu_circ_0000818 was markedly higher in the DEX group com-pared to the control group(P<0.01).Analysis using the UCSC Genome Browser and CircBase indicated that mmu_circ_0000818,located at chromosome 17:78712463-78715086,is formed by the cyclization of exons 6-7 of the Crim1 gene and exhibits high conservation across species.Flow cytometry results indicated that knockdown of mmu_circ_0000818 attenuated DEX-induced apoptosis in MC3T3-E1 cells,while overexpression of mmu_circ_0000818 exacerbated apoptosis.Conclusions CircRNA mmu_circ_0000818 was significantly upregulated in DEX-treated MC3T3-E1 cells,and its downregulation mitigated DEX-induced apoptosis.Consequently,mmu_circ_0000818 may represent a promising therapeutic target for the prevention and treatment of SONFH.

Objective:To compare the efficacy of robot system-assisted versus freehand screw revision for ankylosing spondylitis (AS) with lower cervical fractures.Methods:A multicenter retrospective cohort study was conducted to analyze the clinical data of 57 patients with AS combined with lower cervical fractures admitted to Honghui Hospital Affiliated to Xi'an Jiaotong University School of Medicine, Henan Provincial People's Hospital, Zhengzhou Orthopedic Hospital, and Qilu Hospital of Shandong University, including 46 males and 11 females, aged 38-77 years [(65.4±9.5)years]. Injury segments involved C 3 in 7 patients, C 4 in 13, C 5 in 25, C 6 in 10, and C 7 in 2. All the patients underwent revision surgery, among whom, 22 patients were treated with robot system-assisted cervical pedicle screw placement (robot nailing group, with 190 screws), and 35 with freehand cervical pedicle screw placement (freehand nailing group, with 300 screws). The operative duration, intraoperative bleeding volume, frequency of intraoperative fluoroscopy, incision length, and length of hospital stay of the two groups were compared; the time of single nscrew insertion, the number of single nail revisions, the distance between screws and the anterior cortex, the accuracy of screw placement of grade 0 and grade 0+1 were recorded in the two groups. The visual analogue scale (VAS), Japanese Orthopedic Society (JOA) score, neck dysfunction index (NDI), American Spine Injury Association (ASIA) classification before operation, at 3 days, 3 months after operation and at the last follow-up were compared between the two groups. The complication rate was also noted. Results:All the patients were followed up for 12-16 months [(14.3±2.1)months]. The operative duration, intraoperative bleeding volume, and frequency of intraoperative fluoroscopy were (186.4±12.9)minutes, (486.1±68.6)ml, and (3.4±1.3)times in the robot nailing group, which were shorter or less than (206.7±14.4)minutes, (660.3±45.2)ml, and (13.5±3.6)times in the freehand nailing group ( P<0.01). The incision length was (9.4±2.4)cm in the robot nailing group, longer than (5.6±1.2)cm in the freehand nailing group ( P<0.01), and the length of hospital stay was (3.7±0.4)days, shorter than (4.4±1.4)days in the freehand nailing group ( P<0.01). The length of single nail insertion, the number of single nail revision, and the distance between the screws and the front cortex were (6.5±0.4)minutes, (1.1±0.1)times, and (3.5±1.3)mm in the robot nailing group, which were shorter or less than (11.6±0.2)minutes, (1.5±0.2)times, and (12.4±4.7)mm in the freehand nailing group ( P<0.01). The accuracy of the screw placement in the robot nailing group was 90.0% (171/190) and 95.8% (182/190) with level 0 and 0+1 screws, better than 80.0% (240/300) and 89.0% (267/300) in the freehand nailing group ( P<0.05). There was no significant difference in VAS, JOA score, NDI, or ASIA grading between the two groups before operation ( P>0.05). The VAS, JOA, and NDI scores at 3 days after operation were (3.1±0.6)points, (12.1±1.2)points, and (15.6±2.9)points, respectively in the robot nailing group, which were better than (5.0±1.4)points, (11.3±1.1)points and (22.5±3.7)points, respectively in the freehand nailing group ( P<0.05). No statistically significant difference was observed in the ASIA grade between the two groups at 3 days after operation ( P>0.05). There were no significant differences in VAS, JOA, NDI scores, or ASIA grading between the two groups at 3 months after operation and at the last follow-up ( P>0.05). Compared with those before operation, the VAS, JOA, NDI scores, and ASIA grading were significantly improved at 3 days, 3 months after operation and at the last follow-up in the two groups, which were further improved with the passage of time. Two patients in the robot nailing group had pneumonia, with a complication rate of 9% (2/22), while 2 patients in the freehand nailing group had dural sac rupture and cerebrospinal fluid leakage and 3 had lung infection after operation, with a complication rate of 14% (5/35) ( P<0.05). Conclusion:Compared with freehand nailing, the robot system-assisted nailing revision for AS with lower cervical fracture has more advantages in terms of the operative duration, length of hospital stay, intraoperative bleeding volume, frequency of intraoperative fluoroscopy nailing speed and accuracy, screw holding force, early pain relief, function restoration, and complication rate, despite longer surgical incision.

Objective:To compare the clinical efficacy of navigation system and orthopedic robot-assisted nail placement in the treatment of lower cervical fracture and dislocation.Methods:A retrospective cohort study was conducted to analyze the clinical data of 49 patients with fracture and dislocation of the lower cervical spine who were admitted to Honghui Hospital, Xi′an Jiaotong University School of Medicine from May 2021 to October 2022, including 38 males and 11 females, aged 29-61 years [(39.3±7.3)years]. Injury segments involved C 3 in 12 patients, C 4 in 11, C 5 in 8, C 6 in 9 and C 7 in 9. Twenty-one patients were treated with S8 navigation system (navigation group, 84 screws), and 28 with TINAVI orthopedic robot (robot group, 112 screws). The two groups were compared in terms of the total surgical duration, single screw placement time, total screw placement time, distance between the screw and the anterior cortex, incision length, intraoperative radiation dose, intraoperative blood loss and length of hospital stay. The height of intervertebral space, Cobb angle, sliding distance between vertebral bodies and American Spinal Injury Association (ASIA) grade were assessed before surgery and at 3 days after surgery. Visual analogue scale (VAS), Japanese Orthopedic Association (JOA) score and neck dysfunction index (NDI) before surgery, at 3 days, 3 months after surgery and at the last follow-up were compared. The accuracy of screw placement, intraoperative invasion rate of adjacent facet joints and rate of postoperative complications (infection, screw loosening, etc.) were evaluated. Results:All the patients were followed up for 12-16 months [(13.6±1.9)months]. In the navigation group, the total surgical duration, distance from the screw to the anterior cortex and the intraoperative radiation dose were (236.2±30.6)minutes, (2.0±0.2)mm and (374.3±90.3)mGy respectively, which were significantly shorter or less than those in the robot group [(278.4±20.7)minutes, (10.6±2.9)mm and (448.4±77.9)mGy] ( P<0.01). The single screw placement time, total screw placement time, incision length and intraoperative blood loss were (3.5±0.4)minutes, (23.9±0.5)minutes, (9.1±2.4)cm and (422.2±30.4)ml respectively, which were significantly longer or more than those in the robot group [(2.6±0.2)minutes, (17.9±0.7)minutes, (6.6±2.6)cm and (360.3±56.3)ml] ( P<0.01). There was no significant difference in the length of hospital stay between the two groups ( P>0.05). No significant differences were observed in the height of the intervertebral space, Cobb angle, sliding distance between the vertebral bodies and ASIA grade between the two groups ( P>0.05). At 3 days after surgery, the height of intervertebral space, Cobb angle, sliding distance between vertebral bodies and ASIA grade in both groups were significantly improved when compared with those before surgery ( P<0.05 or 0.01). There were no significant differences in VAS, JOA scores or NDI between the two groups before surgery, at 3 days, 3 months after surgery and at the last follow-up ( P>0.05). The VAS, JOA scores and NDI in both groups were gradually improved at 3 days, 3 months and at the last follow-up after surgery when compared with those before surgery ( P<0.05). There was no significant difference in the accuracy of screw placement of levels 0 and 0+1 between the two groups ( P>0.05). No significant difference in the intraoperative invasion rate of adjacent facet joints between the two groups was found ( P>0.05). There were no serious complications such as infection or screw loosening after surgery in both groups. Conclusions:For lower cervical fracture and dislocation, although there are more advantages in total surgical duration, screw holding force and radiation control regarding the navigation system, and more outstanding performance in screw placement efficiency, incision length and intraoperative blood loss regarding the orthopedic robot, both of them can effectively rebuild the cervical structure, improve neurological function, relieve postoperative pain, improve screw placement accuracy and reduce facet joint injury and serious complications. Selection of the best auxiliary screw placement system should comprehensively consider patients′ conditions and the experience of the surgical team.