Objective:To compare the clinical efficacies of robot-assisted and free-hand long segment screw fixation combined with wedge osteotomy in the treatment of type IV chronic symptomatic osteoporotic thoracolumbar fractures (CSOVCFs).Methods:A retrospective cohort study was conducted to analyze the clinical data of 72 patients with type IV CSOVCFs who were admitted to Honghui Hospital of Xi′an Jiaotong University from May 2019 to December 2021, including 22 males and 46 females; aged 61-82 years [(71.2±12.3)years]. Fracture segments were located at T 11-T 12 in 37 patients and at L 1-L 2 in 31. A total of 32 patients were treated with robot-assisted long segment screw fixation combined with wedge osteotomy (robot group) and 36 with free-hand long segment screw fixation combined with wedge osteotomy (free-hand group). The operation time, intraoperative bleeding volume, dosage of radiation exposure, intraoperative needle adjustment, time of single pedicle screw placement and accuracy of pedicle screw placement were compared between the two groups. The kyphotic Cobb angle, sagittal vertical axis (SVA), thoracic kyphosis (TK), lumbar kyphosis (LL), visual analogue scale (VAS) and Oswestry disability index (ODI) were measured preoperatively, at 3 days postoperatively and at the last follow-up. The incidences of facet joint violation, deviation in guide needle placement, cerebrospinal leak and proximal junctional kyphosis (PJK) were observed. Results:All patients were followed up for 12-26 months [(18.2±5.1)months]. The operation time and time of single pedicle screw placement showed no significant differences between the two groups (all P>0.05). The intraoperative bleeding volume was (502.5±58.3)ml in the robot group, less than that in the free-hand group [(690.2±45.9)ml]. The dosage of radiation exposure was (32.6±10.8)μSv in the robot group, lower than that in the free-hand group [(48.6±15.2)μSv]. The intraoperative needle adjustment was (2.1±0.3)times in the robot group, higher than that in the free-hand group [(20.7±5.8)times], and the accuracy of pedicle screw placement was 99.7% in the robot group, less than that in the free-hand group (91.8%) (all P<0.01). Compared with pre-operation, the kyphotic Cobb angle, SVA, TK and LL were significantly improved in both groups at postoperative 3 days and at the last follow-up (all P<0.05). Compared with postoperative 3 days, the kyphotic Cobb angle, SVA and TK were increased at the last follow-up within the two groups, but with no significant differences (all P>0.05). Compared with postoperative 3 days, the LL was decreased within the two groups at the last follow-up, but with no significant differences (all P>0.05). The VAS and ODI in the two groups were significantly lower at postoperative 3 days and at the last follow-up when compared with those before operation (all P<0.05), and both values were significantly lower at the last follow-up than those at postoperative 3 days (all P<0.05). There were no significant differences in the VAS or ODI at all time points between the two groups (all P>0.05). The incidence of facet joint violation in the robot group was 1.6%, markedly lower than that in the free-hand group (9.6%) ( P<0.01). The incidences of deviation in guide needle placement, cerebrospinal leak and PJK showed no differences between the two groups (all P>0.05). Conclusion:For type IV CSOVCFs, the robot-assisted long segment screw fixation combined with wedge osteotomy can better reduce intraoperative blood loss, decrease radiation exposure, improve accuracy of pedicle screw placement, and reduce facet joint violation when compared with free-hand long segment screw fixation combined with wedge osteotomy.

Objective:To compare the clinical efficacies of O-arm combined with CT three-dimensional navigation system assisted screw placement versus manual screw placement in treating lower cervical fracture and dislocation.Methods:A retrospective cohort study was used to analyze the clinical data of 41 patients with lower cervical fracture and dislocation, who were treated in Honghui Hospital, Xi′an Jiaotong University from May 2021 to February 2022. The patients included 26 males and 15 females, aged 31.5-48.6 years [(41.5±15.0)years]. The injured segments were C 3 in 3 patients, C 4 in 12, C 5 in 13, C 6 in 10 and C 7 in 3. Nineteen patients were treated with cervical pedicle screws by O-shaped arm combined with CT three-dimensional navigation system (navigation group, 76 screws) and 22 by bare hands (traditional group, 88 screws). The total operation time, effective operation time, single nail placement time, single screw correction times, screw distance from anterior cortex, intraoperative blood loss, intraoperative fluoroscopic radiation dose, incision length and length of hospital stay were compared between the two groups, and the height of intervertebral space, Cobb angle, interbody slip distance and American Spinal injury Association (ASIA) grade were compared before operation and at 3 days after operation. Visual analogue score (VAS), Japanese Orthopedic Association (JOA) score, and neck dysfunction index (NDI) were evaluated before operation, at 3 days, 3 months after operation and at the last follow-up. Accuracy of screw placement and incidence of complications (adjacent facet joint invasion, infection, screw loosening) were detected as well. Results:All the patients were followed up for 11.1-13.9 months [(12.5±1.4)months]. The total operation time, intraoperative blood loss, intraoperative fluoroscopic radiation dose and incision length in the navigation group were more or longer than those in the traditional group (all P<0.05). The effective operation time, single nail placement time, single nail correction times and screw distance from anterior cortex in the navigation group were markedly less or smaller than those in the traditional group (all P<0.05). There was no significant difference in the length of hospital stay between the two groups ( P>0.05). There were significant improvements in the height of intervertebral space, Cobb angle and interbody slip distance between the two groups at 3 days after operation (all P<0.05). There was no significant difference in the height of intervertebral space, Cobb angle, interbody slip distance or ASIA grade between the two groups before operation or at 3 days after operation (all P>0.05). Compared with pre-operation, the VAS, JOA score and NDI were significantly improved in both groups at 3 days, 3 months after operation and at the last follow-up (all P<0.05), with further improvement with time. There was no significant difference in VAS between the two groups before operation or at 3 months after operation (all P>0.05), but it was markedly lower in the navigation group compared with the traditional group at 3 days after operation and at the last follow-up (all P<0.05). There were no significant differences in JOA score or NDI between the two groups before operation or at 3 days and 3 months after operation (all P>0.05), but both were lower in the navigation group compared with the traditional group at the last follow-up (all P<0.05). The accuracies of placement of grade 0 and grade 0+1 screws were 92.0% (70/76) and 96.6% (73/76) in the navigation group, respectively, which were markedly higher than 88.7% (78/88) and 93.5% (82/88) in the traditional group (all P<0.05). The rates of adjacent facet joint invasion of A, B, and C degrees were 71.2% (54/76), 28.8% (22/76) and 0% (0/76) in the navigation group, respectively, while the invasion rates were 60.5% (53/88), 32.3% (28/88) and 7.3% (7/88) in the traditional group ( P<0.05). No screw loosening was noted in the navigation group, but the screw loosening rate was 9.1% (8/88) in the traditional group ( P<0.01). Conclusion:Compared with manual screw placement, O-arm combined with CT three-dimensional navigation system assisted screw placement for lower cervical fracture and dislocation has the advantages of shorter effective operation time, quicker screw placement, stronger screw holding force, better cervical stability, slighter postoperative pain, higher screw placement accuracy, and lower facet joint invasion and screw loosening rates.

Objective:To establish and validate a fluorescence focus assay (FFA) for rapid titration of Japanese encephalitis virus (JEV) and to evaluate its application in the production of Japanese encephalitis vaccine.Methods:Recombinant JEV non-structural protein 1 (NS1) was expressed in a prokaryotic expression system. After purification, JEV-NS1 was used to immunize rabbits to induce polyclonal antibody. FFA was established with the polyclonal antibody to titer JEV. The accuracy of FFA was validated by comparing with plaque assay, and the specificity, precision, linearity, range and robustness of FFA were also validated. Twenty-eight batches of live-attenuated Japanese encephalitis vaccine were titrated with FFA and plaque assay to analyze the relationship between the two assays.Results:FFA established with polyclonal antibody against JEV-NS1 could be used to titrate JEV, and there was no cross reaction with other viruses (tick-borne encephalitis virus, yellow fever virus, coxsackievirus A2, coxsackievirus A4). Results of the validation tests showed that FFA met the requirement of quality control for live-attenuated Japanese encephalitis vaccine. FFA was more consistency than plaque assay.Conclusions:The established FFA could be used for virus titration in the production of live-attenuated Japanese encephalitis vaccine.

Objective:To evaluate the efficacy of unilateral puncture techniques in high-viscosity cement percutanueous vertebroplasty (PVP) in treatment of type I chronic symptomatic osteoporotic vertebral compression fracture (CSOVCF).Methods:A retrospective case control study was conducted to analyze the clinical data of 119 patients with type I CSOVCF admitted to Honghui Hospital affiliated to Xi'an Jiaotong University School of Medicine from December 2013 to December 2016. There were 42 males and 77 females, aged 58-95 years [(79.2±15.6)years]. All patients had bone mineral density of -4.5--2.5 SD [(-3.9±0.2)SD] (T score). The fractured segments included L 1-L 2 in 56 patients and L 3-L 5 in 63. All patients were treated by high-viscosity cement PVP with the unilateral puncture of transverse process and superior articular process in unilateral group ( n=60) and by the bilateral puncture approach with the Magerl method in bilaleral group ( n=59). The operation time, cement injection volume, and intraoperative fluoroscopy frequency were recorded. The visual analogue scale (VAS), Oswestry dysfunction index (ODI), anterior height ratio of injured vertebrae and Cobb angle were measured before operation, at postoperative 1 day and at the last follow-up. The adjacent vertebral fracture, cement leakage and other complications were recorded. Results:All patients were followed up for 12-48 months [(24.1±5.6)months]. The operation time in unilateral group [(21.5±6.5)minutes] was significantly shorter than that in bilateral group [(37.8±7.4)minutes] ( P<0.05). The cement injection volume in unilateral group [(4.2±0.7)ml] was less than that in bilateral group [(6.5±1.1)ml]( P<0.05). The intraoperative fluoroscopy frequency in unilateral group [(14.2±3.0)times] was less than that in bilateral group [(31.4±6.4)times] ( P<0.05). Both groups showed significant improvements in VAS, ODI, anterior height ratio of injured vertebrae and Cobb angle at postoperative 1 day and at the last follow-up compared with these before operation ( P<0.05), but there were no significant differences after operation between the two groups ( P>0.05). The incidence of adjacent vertebral fracture was 5%(3/60) in unilateral group and 8% (5/59) in bilaleral group ( P>0.05). Four patients (7%) had cement leakage in unilateral group and 11 patients (19%) in bilateral group ( P<0.05). No complications of wound infection, nerve injury or pulmonary embolism occurred. Conclusion:Compared with Magerl bilateral puncture approach, high-viscosity cement PVP with unilateral puncture of transverse process and superior articular process in treatment of type I CSOVCF has advantages of shorter operation time, less trauma, less radiation exposure and lower cement leakage rate.

Objective:To evaluate the efficacy and impacts of air tamponadein treating rhegmatogenous retinal detachments (RRD) including inferior breaks after 25G pars plana vitrectomy (PPV).Methods:A prospective non-randomized study. From November 2016 to December 2018, 110 RRD patients receiving PPV in the Ophthalmology Department of Affiliated Hospital of Nantong University were included in the study. All the patients choose the operation mode voluntarily after fully understand the condition and operation mode. There were 90 eyes in the air filling group and 20 eyes in the silicone oil filling group. There was no difference of age ( t=-0.082), sex ratio ( χ2=1.538), left or right eye ( χ2=0.839), average course of disease ( Z=-0.276), intraocular pressure ( t=3.669), axial length ( t=0.765), grade of proliferative vitreous retinopathy ( Z=-2.101), high myopia ( χ2=0.013), lens state ( χ2=1.275), logMAR BCVA ( t=-0.681), the scope of retinal detachment ( t=0.970), the site ( χ2=0.108) and numbers ( t=0.158) of the retinal holes, whether involving macula ( χ2=1.791) between the two groups ( P>0.05). At 1, 3, and 6 months after surgery, the first retinal reduction rate, BCVA increase rate, visual recovery rate, intraocular pressure, fovea retinal thickness (CFT), ellipsoid and cross sectional area, and the occurrence of postoperative complications in the two groups were observed and compared. Independent sample t test and Chi-squared test, Mann-Whitney U test, and ANOVA were used for data comparision. Results:After the first operation, retinal reattachmnents were achieved in 87 eyes (96.6%) in the air group and 19 eyes (95.0%) in the silicone oil group ( χ2=0.130, P>0.05). In the air group and the silicone oil group, there were 7 and 2 eyes with subretinal holes, whose retinal reattachmnents were achieved. At 6 months after surgery, logMAR BCVA of the eyes in the air group and the silicone oil group were 0.23±0.23 and 0.37±0.23, respectively. All of them were higher than that before operation ( t=-2.410, P<0.001). BCVA in the air group was superior to that in the silicone oil group ( P<0.05). The increase rate of BCVA of the eyes in the air group and the silicone oil group were 0.69±0.28 and 0.48±0.30 logMAR units, respectively ( t=-3.225, P<0.05). The CFT of the eyes in the air group and the silicone oil group were 226.87±42.30 μm and 234.83±36.10 μm, respectively ( t=-0.448, P=0.657). In the air group and silicone oil group, posterior cataract was observed in 15 and 4 eyes, subretinal residual fluid in 1 and 2 eyes, and visual object deformation in 3 eyes respectively. In the air group and silicone oil group, posterior cataract was observed in 15 and 4 eyes, subretinal residual fluid in 1 and 2 eyes, and visual object deformation in 3 eyes respectively. Conclusions:Air filling combined with PPV can effectively treat RRD, which is suitable for both superior and inferior holes. The visual acuity recovered well and the complication is less. The time of retinal detachment (especially the time of macular detachment) is an important factor affecting the prognosis.

Objective To evaluate the precise percutaneous sacroplasty (PSP) assisted by a Renaissance robot for sacral insufficiency fractures (SIF).Methods The clinical data of 12 SIF patients were retrospectively analyzed who had been treated from March 2016 to March 2018 at Department of Spinal Surgery,Honghui Hospital.They were 5 males and 7 females,aged from 55 to 76 years (average,67.5 years).They all received PSP assisted by a Renaissance robot.Their operation time,hospital stay and intraoperative radiation were recorded.The clinical efficacy was evaluated by comparing their visual analogue scale (VAS) and Oswestry disability index (ODI) before surgery,1 day,3 and 12 months after surgery.Results All the 12 patients underwent surgery successfully with no complications like cement leakage.Their operation time ranged from 32 to 47 minutes (mean,36.8 minutes),their hospital stay from 12 to 25 hours (mean 17.5 hours) and their intraoperative exposure to radiation from 0.87 to 1.53 mSv (mean,1.27 mSv).All the patients were followed up for 12 to 18 months (mean,15.8 months).Their VAS (1.7 ± 0.7) and ODI (22.8 ± 4.1) one day after surgery were significantly decreased than the preoperative values (7.6 ±0.9 and 43.7 ±4.6) (P ＜ 0.05).At 3 and 12 months after surgery,their VAS scores were 2.0 ± 0.8 and 2.4 ±0.8 and their ODI scores 21.5 ±4.3 and 23.0 ±4.6,respectively,showing no significant differences from the values at 1 day after surgery (P ＞ 0.05).Conclusion The PSP assisted by a Renaissance robot is safe and leads to satisfactory clinical efficacy for SIF as bone cement can be accurately injected into the target area of the fracture.

Objective: To compare the efficacy of unilateral and bilateral percutaneous kyphoplasty (PKP) for thoracolumbar osteoporotic vertebral compression fractures (OVCFs). Methods: A retrospective case control study was conducted to analyze the clinical data of 234 OVCFs patients admitted to Honghui Hospital affiliated to Xi'an Jiaotong University Medical College from June 2014 to January 2016. There were 95 males and 139 females, aged 60-89 years, with an average age of 68.3 years. The fractured segments included T₁₁ in 45 patients, T₁₂ in 65 patients, L₁ in 72 patients, and L₂ in 52 patients. A total of 116 patients were treated with PKP through unilateral puncture of transverse process and superior articular process (unilateral group), and 118 patients were treated with PKP through bilateral puncture of Magerl (bilateral group). The operation time, radiation exposure, bone cement injection and leakage were compared between the two groups. Visual analogue scale (VAS) and Oswestry dysfunction index (ODI) were used to evaluate the clinical efficacy and life quality improvement. The distribution of bone cement was observed by CT. The complications were recorded. Results: All patients were followed up for 25-36 months, with an average of 27 months. The operation time of unilateral group [(19.6±5.3)minutes] was significantly shorter than that of bilateral group [(35.6±8.9)minutes]; the radiation exposure [(0.65±0.22)mSv] was lower than that of bilateral group [(1.69±0.58)mSv]; the bone cement injection [(5.3±0.8)ml] was less than that of bilateral group [(6.5±1.3)ml] (P<0.05). The postoperative X-ray showed that 10 patients (8.6%) in the unilateral group and 22 patients (18.6%) in the bilateral group (P<0.05) were found with bone segment leakage, although without clinical symptoms. The postoperative VAS and ODI of the two groups were significantly improved than before operation (P<0.01), and there was no significant difference between the two groups (P>0.05). Bone cement was mainly distributed in the front and middle of the vertebral body (A2, B1, C2, D1) in the unilateral group and in the front 2/3 of the vertebral body (A, B, C, D) in the bilateral group. There were in total 10 patients with cerebrospinal fluid during intraoperative puncture, including two patients in the unilateral group and eight patients in the bilateral group (P>0.05). The puncture direction was adjusted during the operation, and there was no neurological damage after the operation. There were 16 patients with local pain caused by small joint injury, including two patients in unilateral group and 14 patients in bilateral group (P<0.05). The pain was relieved one month after physical treatment. A total of 30 patients had vertebral fracture again, including 18 in unilateral group and 12 in bilateral group (P>0.05), all of whom were treated with PKP again. Conclusion Compared with Magerl bilateral approach, PKP for OVCFs has the advantages of shorter operation time, less radiation exposure, low leakage rate of bone cement and good distribution of bone cement.

Objective To investigate outcomes of posterior instrumentation and fusion in treating ankylosing spondylitis (AS) combined with lower cervical fractures.Methods A retrospective case series study was made on 53 AS patients combined with cervical fractures or cervical thoracic fractures treated by posterior instrumentation and fusion from January 2006 to January 2013.There were 51 male and 2 female patients.The mean age of patients was 55 years old (range,34-69 years old).All the patients showed significant kyphosis on the thoracolumbar and cervicothoracic junction.A total of 20 patients had neurological dysfunction at different extents.According to the American spinal injury association (ASIA) classification,neurological status was scored as Grade A in 4 cases,Grade B in 5,Grade C in 4 and Grade D in 7.The operation time,total bleeding and decompression status were recorded during the surgery.Reduction,decompression condition and complications were evaluated.The neurological status and bone fusion were recorded at the follow-up.Results All surgeries were well accomplished.Mean surgical time was 3.7 h (range,2.9-5.3 h).Mean total bleeding was 690 ml (range,470-1 600 ml).Two patients died within 1 year follow-up because of internal diseases (1 case caused by respiratory system disease in 13 months postoperatively and 1 case caused by acute myocardial infarction in 15 months postoperatively).The mean follow-up time of other patients was 25 months (range,18-48 months).The CT scan manifested all patients achieved satisfactory fusion,and the mean time span of the fusion was 3.5 months (range,3-6 months) postoperatively.Among the 20 patients with various levels of neurological deficits before operation,the postoperative ASIA score was Grade A in 4 cases,Grade C in 2,Grade D in 4,and Grade E in 10.No instrumentation failure occurred during follow-up.Conclusion The posterior instrumentation and fusion for treating AS combined with cervical fractures can obtain satisfactory neurological results,spinal stabilization and clinical results,and hence an effective clinical problem-solving algorithm for such kind of patients.

Objective To evaluate the miRNA change between hypothermia circulatory arrest at different temperature and its impact on intestinal protection.Methods Sixteen piglets were randomly(n =4) divided into four groups:deep hypothermia circulatory arrest (DHCA,18℃) group,moderate hypothermia circulatory arrest(MHCA,24℃) group,cardiopulmonary bypass(CPB) group and sham operation(SO) group.They were subjected to 80 min hypothermia circulatory arrest,305 min CPB or thoracotomy,respectively.Pick-and-mix custom miRNA real-time PCR panels were utilized to detect intestinal samples.miRNA expression between DHCA and MHCA were compared directly(DHCA vs.MHCA) and indirectly(DHCA/SO vs.MHCA/SO,DHCA/CPB vs.MHCA/CPB).Results Exposure to DHCA caused less intestinal miRNA dysregulation than MHCA.Besides,seven miRNAs(miR-122,miR-145-5p,miR-421-5p,miR-99a,miR-365-5p,miR-31 and miR-192)were differentially expressed between the two hypothermia circulatory arrest groups.Conclusion Better intestinal miRNA protection was provided by DHCA than MHCA.Intestinal miRNA were differentially expressed between hypothermia circulatory arrest at different temperature.

Objective To evaluate the clinical outcomes of sacral decompression and lumbopelvic fixation for neurologically impaired patients with sacral fracture-dislocation.Methods From January 2009 to December 2013,32 patients with sacral fracture and spino-pelvic dissociation of Roy-Camille types Ⅱand Ⅲ were treated at our department.They were 21 men and 11 women,with a mean age of 34.3 years.According to Roy-Camille classification,9 patients belonged to type Ⅱand 23 to type Ⅲ;25 patients had S1 fracture-dislocation and 7 S2 fracture-dislocation.After their overall conditions were stabilized,all were treated with open reduction,sacral decompression and lumbopelvic fixation.Pre-and post-operative neurological functions were recorded by Gibbons criteria.We analyzed the correlations between the neurological recovery and (i) the extent of cauda equina deficit and (ii) the continuity of sacral roots,as well as the correlations between the functional recovery of the bladder and bowels and the above two.The reduction and fusion status were evaluated by the Mears and Velyvis radiological criteria;clinical effectiveness was evaluated by Majeed scoring system.Intra-and post-operative complications were all recorded.Results The mean follow-up time for this series was 35 months (from 25 to 47 months).The average Gibbons score improved from 4.0 to 2.7 at the follow-ups.The patients with mild cauda equina deficit or with continuity of sacral roots achieved significantly better neurological recovery than those with severe cauda equina deficit or with discontinuity of sacral roots (P ＜ 0.001).However,the functional recovery of the bladder or bowels was not significantly correlated with the extent of cauda equina deficit or with the continuity of sacral roots.Anatomical reduction was achieved in 26 patients,satisfactory reduction in 5 and unsatisfactory reduction in one,yielding a satisfaction rate of 96.9％.Bony fusion was obtained in 29 patients at 3 months,but not until at 9 months in 2 patients,and still not at 9 months in one who showed no symptoms.The Majeed scoring showed 22 excellent,6 good and 4 moderate cases,giving an excellent to good rate of 87.5％.Two patients developed deep wound infection,3 complained of the pain related to hardware prominence,and one had unilateral rod breakage.Conclusions In treatment of sacral fracture with spino-pelvic dissociation,sacral decompression and lumbopelvic fixation can lead to effective neurological recovery,restoration of lumboscacral stability and alignment,early ambulation and prevention of deformity.Complete neurological recovery is more likely in patients with incomplete cauda equina deficit or with continuity of all sacral roots.