Background: s/Aims: Non-invasive models stratifying clinically significant portal hypertension (CSPH) are limited. Herein, we developed a new non-invasive model for predicting CSPH in patients with compensated cirrhosis and investigated whether carvedilol can prevent hepatic decompensation in patients with high-risk CSPH stratified using the new model. Methods: Non-invasive risk factors of CSPH were identified via systematic review and meta-analysis of studies involving patients with hepatic venous pressure gradient (HVPG). A new non-invasive model was validated for various performance aspects in three cohorts, i.e., a multicenter HVPG cohort, a follow-up cohort, and a carvediloltreating cohort. Results: In the meta-analysis with six studies (n=819), liver stiffness measurement and platelet count were identified as independent risk factors for CSPH and were used to develop the new “CSPH risk” model. In the HVPG cohort (n=151), the new model accurately predicted CSPH with cutoff values of 0 and –0.68 for ruling in and out CSPH, respectively. In the follow-up cohort (n=1,102), the cumulative incidences of decompensation events significantly differed using the cutoff values of <–0.68 (low-risk), –0.68 to 0 (medium-risk), and >0 (high-risk). In the carvediloltreated cohort, patients with high-risk CSPH treated with carvedilol (n=81) had lower rates of decompensation events than non-selective beta-blockers untreated patients with high-risk CSPH (n=613 before propensity score matching [PSM], n=162 after PSM). Conclusions Treatment with carvedilol significantly reduces the risk of hepatic decompensation in patients with high-risk CSPH stratified by the new model.

Background: s/Aims: Non-invasive models stratifying clinically significant portal hypertension (CSPH) are limited. Herein, we developed a new non-invasive model for predicting CSPH in patients with compensated cirrhosis and investigated whether carvedilol can prevent hepatic decompensation in patients with high-risk CSPH stratified using the new model. Methods: Non-invasive risk factors of CSPH were identified via systematic review and meta-analysis of studies involving patients with hepatic venous pressure gradient (HVPG). A new non-invasive model was validated for various performance aspects in three cohorts, i.e., a multicenter HVPG cohort, a follow-up cohort, and a carvediloltreating cohort. Results: In the meta-analysis with six studies (n=819), liver stiffness measurement and platelet count were identified as independent risk factors for CSPH and were used to develop the new “CSPH risk” model. In the HVPG cohort (n=151), the new model accurately predicted CSPH with cutoff values of 0 and –0.68 for ruling in and out CSPH, respectively. In the follow-up cohort (n=1,102), the cumulative incidences of decompensation events significantly differed using the cutoff values of <–0.68 (low-risk), –0.68 to 0 (medium-risk), and >0 (high-risk). In the carvediloltreated cohort, patients with high-risk CSPH treated with carvedilol (n=81) had lower rates of decompensation events than non-selective beta-blockers untreated patients with high-risk CSPH (n=613 before propensity score matching [PSM], n=162 after PSM). Conclusions Treatment with carvedilol significantly reduces the risk of hepatic decompensation in patients with high-risk CSPH stratified by the new model.

Background: s/Aims: Non-invasive models stratifying clinically significant portal hypertension (CSPH) are limited. Herein, we developed a new non-invasive model for predicting CSPH in patients with compensated cirrhosis and investigated whether carvedilol can prevent hepatic decompensation in patients with high-risk CSPH stratified using the new model. Methods: Non-invasive risk factors of CSPH were identified via systematic review and meta-analysis of studies involving patients with hepatic venous pressure gradient (HVPG). A new non-invasive model was validated for various performance aspects in three cohorts, i.e., a multicenter HVPG cohort, a follow-up cohort, and a carvediloltreating cohort. Results: In the meta-analysis with six studies (n=819), liver stiffness measurement and platelet count were identified as independent risk factors for CSPH and were used to develop the new “CSPH risk” model. In the HVPG cohort (n=151), the new model accurately predicted CSPH with cutoff values of 0 and –0.68 for ruling in and out CSPH, respectively. In the follow-up cohort (n=1,102), the cumulative incidences of decompensation events significantly differed using the cutoff values of <–0.68 (low-risk), –0.68 to 0 (medium-risk), and >0 (high-risk). In the carvediloltreated cohort, patients with high-risk CSPH treated with carvedilol (n=81) had lower rates of decompensation events than non-selective beta-blockers untreated patients with high-risk CSPH (n=613 before propensity score matching [PSM], n=162 after PSM). Conclusions Treatment with carvedilol significantly reduces the risk of hepatic decompensation in patients with high-risk CSPH stratified by the new model.

Objective To observe the cage subsidence after oblique lateral interbody fusion(OLIF)for lumbar spondylo-sis,summarize the characteristics of the cage subsidence,analyze causes,and propose preventive measures.Methods The data of 144 patients of lumbar spine lesions admitted to our hospital from October 2015 to December 2018 were retrospectively ana-lyzed.There were 43 males and 101 females,and the age ranged from 20 to 81 years old,with an average of(60.90±10.06)years old.Disease types:17 patients of lumbar intervertebral disc degenerative disease,12 patients of giant lumbar disc hernia-tion,5 patients of discogenic low back pain,33 patients of lumbar spinal stenosis,26 patients of lumbar degenerative spondy-lolisthesis,28 patients of lumbar spondylolisthesis with spondylolisthesis,11 patients of adjacent vertebral disease after lumbar internal fixation,7 patients of primary spondylitis in the inflammatory outcome stage,and 5 patients of lumbar degenerative scoliosis.Preoperative dual-energy X-ray bone mineral density examination showed 57 patients of osteopenia or osteoporosis,and 87 patients of normal bone density.The number of fusion segments:124 patients of single-segment,11 patients of two-seg-ment,8 patients of three-segment,four-segment 1 patient.There were 40 patients treated by stand-alone OLIF,and 104 patients by OLIF combined with posterior pedicle screw.Observed the occurrence of fusion cage settlement after operation,conducted monofactor analysis on possible risk factors,and observed the influence of fusion cage settlement on clinical results.Results All operations were successfully completed,the median operation time was 99 min,and the median intraoperative blood loss was 106 ml.Intraoperative endplate injury occurred in 30 patients and vertebral fracture occurred in 5 patients.The mean follow-up was(14.57±7.14)months from 6 to 30 months.During the follow-up,except for the patients of primary lumbar interstitial in-flammation and some patients of lumbar spondylolisthesis with spondylolisthesis,the others all had different degrees of cage subsidence.Cage subsidence classification:119 patients were normal subsidence,and 25 patients were abnormal subsidence(23 patients were grade Ⅰ,and 2 patients were grade Ⅱ).There was no loosening or rupture of the pedicle screw system.The height of the intervertebral space recovered from the preoperative average(9.48±1.84)mm to the postoperative average(12.65±2.03)mm,and the average(10.51±1.81)mm at the last follow-up.There were statistical differences between postop-erative and preoperative,and between the last follow-up and postoperative.The interbody fusion rate was 94.4％.The low back pain VAS decreased from the preoperative average(6.55±2.2 9)to the last follow-up(1.40±0.82),and there was statistically significant different.The leg pain VAS decreased from the preoperative average(4.72±1.49)to the final follow-up(0.60± 0.03),and the difference was statistically significant(t=9.13,P＜0.000 1).The ODI index recovered from the preoperative av-erage(38.50±6.98)％to the latest follow-up(11.30±3.27)％,and there was statistically significant different.The complication rate was 31.3％(45/144),and the reoperation rate was 9.72％(14/144).Among them,8 patients were reoperated due to fusion cage subsidence or displacement,accounting for 57.14％(8/14)of reoperation.The fusion cage subsidence in this group had obvious characteristics.The monofactor analysis showed that the number of abnormal subsidence patients in the osteopenia or osteoporosis group,Stand-alone OLIF group,2 or more segments fusion group,and endplate injury group was higher than that in the normal bone mass group,OLIF combined with pedicle screw fixation group,single segment fusion group,and no endplate injury group,and the comparison had statistical differences.Conclusion Cage subsidence is a common phenomenon after 0-LIF surgery.Preoperative osteopenia or osteoporosis,Stand-alone OLIF,2 or more segments of fusion and intraoperative end-plate injury may be important factors for postoperative fusion cage subsidence.Although there is no significant correlation be-tween the degree of cage subsidence and clinical symptoms,there is a risk of cage migration,and prevention needs to be strengthened to reduce serious complications caused by fusion of cage subsidence,including reoperation.

Objective To summarize the reasons and management strategies of reoperation after oblique lateral interbody fusion(OLIF),and put forward preventive measures.Methods From October 2015 to December 2019,23 patients who under-went reoperation after OLIF in four spine surgery centers were retrospectively analyzed.There were 9 males and 14 females with an average age of(61.89±8.80)years old ranging from 44 to 81 years old.The index diagnosis was degenerative lumbar intervertebral dics diseases in 3 cases,discogenie low back pain in 1 case,degenerative lumbar spondylolisthesis in 6 cases,lumbar spinal stenosis in 9 cases and degenerative lumbar spinal kyphoscoliosis in 4 cases.Sixteen patients were primarily treated with Stand-alone OLIF procedures and 7 cases were primarily treated with OLIF combined with posterior pedicle screw fixation.There were 17 cases of single fusion segment,2 of 2 fusion segments,4 of 3 fusion segments.All the cases underwent reoperation within 3 months after the initial surgery.The strategies of reoperation included supplementary posterior pedicle screw instrumentation in 16 cases;posterior laminectomy,cage adjustment and neurolysis in 2 cases,arthroplasty and neuroly-sis under endoscope in 1 case,posterior laminectomy and neurolysis in 1 case,pedicle screw adjustment in 1 case,exploration and decompression under percutaneous endoscopic in 1 case,interbody fusion cage and pedicle screw revision in 1 case.Visu-al analogue scale(VAS)and Oswestry disability index(ODI)index were used to evaluate and compare the recovery of low back pain and lumbar function before reoperation and at the last follow-up.During the follow-up process,the phenomenon of fusion cage settlement or re-displacement,as well as the condition of intervertebral fusion,were observed.The changes in in-tervertebral space height before the first operation,after the first operation,before the second operation,3 to 5 days after the second operation,6 months after the second operation,and at the latest follow-up were measured and compared.Results There was no skin necrosis and infection.All patients were followed up from 12 to 48 months with an average of(28.1±7.3)months.Nerve root injury symptoms were relieved within 3 to 6 months.No cage transverse shifting and no dislodgement,loosening or breakage of the instrumentation was observed in any patient during the follow-up period.Though the intervertebral disc height was obviously increased at the first postoperative,there was a rapid loss in the early stage,and still partially lost after reopera-tion.The VAS for back pain recovered from(6.20±1.69)points preoperatively to(1.60±0.71)points postoperatively(P＜0.05).The ODI recovered from(40.60±7.01)％preoperatively to(9.14±2.66)％postoperatively(P＜0.05).Conclusion There is a risk of reoperation due to failure after OLIF surgery.The reasons for reoperation include preoperative bone loss or osteoporosis the initial surgery was performed by Stand-alone,intraoperative endplate injury,significant subsidence of the fusion cage after surgery,postoperative fusion cage displacement,nerve damage,etc.As long as it is discovered in a timely manner and handled properly,further surgery after OLIF surgery can achieve better clinical results,but prevention still needs to be strengthened.

Objective To carry out rigid-body inverse dynamics modelling and analysis of a self-designed 6RSS parallel bio-inspired masticatory robot.Methods Firstly,the functions of kinematic variables including translational/rotational velocities and accelerations were derived for rigid-body inverse dynamics modelling.Secondly,the rigid-body inverse dynamics model was established with the Newton-Euler's law.Finally,the chewing motion trajectories of the oral health volunteers were tracked and numerical calculations were carried out in the case where the robot was subjected to a chewing reaction force.Results Numerical calculations showed that the driving torque and the constraint force of the robot peaked when the chewing reaction force was at its maximum.Conclusion The external force has a large impact on the inverse dynamics of the robot,and theoretical references are provided for the motion control and optimal design of the robot.[Chinese Medical Equipment Journal,2024,45(3):16-22]

The aim of this study is to investigate the immune effect of H9 subtype avian influenza virus(AIV)NP protein on mice and lay the foundation for the development of avian influenza vi-rus(AIV)vaccine.The H9N2 virus NP gene amplification product was cloned into the pET-32a expression vector,and the protein expression was verified by SDS-PAGE and Western blot,and the immune effect was evaluated by measuring the secretion of supernatant multicytokines in mouse splenocytes culture.The results showed that the total length of the coding region sequence of NP gene was 1 497 bp,NP recombinant proteins exist in both soluble and insoluble protein forms,and the specific bands were visible in Western blot.After immunizing mice,serum produces IgG-bind-ing antibodies with antibody titers of 1∶40 000.Compared with the control group,IL-2,IL-5 and IL-13 were significantly increased(P＜0.001),and the secretion of IL-6 was significantly increased compared with the control group.IL-4 and IL-12 p70 secretions were elevated compared with con-trols,but there was no significant difference.Compared with the control group,the secretions of IL-1β,IL-18,GM-CMF,TNF-α and IFN-γ were inhibited,but the difference was not significant(P＞0.05).The results showed that NP recombinant protein is a good immunogen,laying a foundation for in-depth research on influenza vaccine.

OBJECTIVE: To explore the feasibility and clinical effect of Stand-alone oblique lateral interbody fusion (OLIF) in the treatment of lumbar intervertebral disc degeneration with Modic changes and endplate sclerosis. METHODS: A retrospective analysis was performed on 16 cases with lumbar intervertebral disc degeneration with Modic changes and endplate sclerosis admitted to three medical centers from January 2015 to December 2018. There were 6 males and 10 females, the age ranged from 45 to 67 years old with an average of (55.48±8.07) years old, the medical history ranged from 36 to 240 months with an average of (82.40±47.68) months. The lesion sites included L_2,3 in 2 cases, L_3,4 in 5 cases, and L_4,5 in 9 cases. All patients presented with chronic low back pain with lower limb neurological symptoms in 3 cases. All patients were treated by Stand-alone oblique lateral lumbar interbody fusion. Clinical and radiological findings and complications were observed. RESULTS: There was no vascular injury, endplate injury and vertebral fracture during the operation. The mean incision length, operation time, and intraoperative blood loss were(4.06±0.42) cm, (45.12±5.43) min, (33.40±7.29) ml, respectively. The mean visual analogue scale (VAS) of the incision pain was (1.14±0.47) at 72 hours after operation. There was no incision skin necrosis, poor incision healing or infection in patients. Sympathetic chain injury occurred in 1 case, anterolateral pain and numbness of the left thigh in 2 cases, and weakness of the left iliopsoas muscle in 1 case, all of which were transient injuries with a complication rate of 25%(4/16). All 16 patients were followed up from 12 to 36 months with an average of (20.80±5.46) months. The intervertebral space height was significantly recovered after operation, with slight lost during the follow-up. Coronal and sagittal balance of the lumbar spine showed good improvement at the final follow-up. There was no obvious subsidence or displacement of the cage, and the interbody fusion was obtained. At the final follow-up, Japanese Orthopaedic Association(JOA) score and Oswestry disability index(ODI) were significantly improved. CONCLUSION As long as the selection of case is strict enough and the preoperative examination is sufficients, the use of Stand-alone OLIF in the treatment of lumbar intervertebral disc degeneration with Modic changes and endplate sclerosis has a good results, with obvious clinical advantages and is a better surgical choice.
Male ; Female ; Humans ; Child, Preschool ; Intervertebral Disc Degeneration/surgery* ; Retrospective Studies ; Sclerosis ; Treatment Outcome ; Lumbar Vertebrae/surgery* ; Spinal Fusion/methods*

OBJECTIVE: To analyze the causes of vertebral fracture during oblique lateral interbody fusion in the treatment of lumbar spondylopathy, summarize the clinical results, and propose preventive measures. METHODS: Retrospective analysis was made on the data of 8 cases of lumbar spondylopathy and vertebral fracture treated by oblique lateral interbody fusion in three medical centers from October 2014 to December 2018. All were female, aged from 50 to 81 years with an average of 66.4 years. Disease types included 1 case of lumbar degenerative disease, 3 cases of lumbar spinal stenosis, 2 cases of lumbar degenerative spondylolisthesis and 2 cases of lumbar degenerative scoliosis. Preoperative dual energy X-ray bone mineral density test showed that 2 cases had T-value >-1 SD, 2 cases had T-value -1 to -2.5 SD, and 4 cases had T-value <-2.5 SD. Single segment fusion was in 5 cases, two segment fusion in 1 case and three segment fusion in 2 cases. Four cases were treated with OLIF Stand-alone and 4 cases were treated with OLIF combined with posterior pedicle screw fixation. Postoperative imaging examination showed vertebral fracture, and all of them were single vertebral fracture. There were 2 cases of right lower edge fracture of upper vertebral body at fusion segment, 6 cases of lower vertebral body fracture at fusion segment, and 6 cases with endplate injury and fusion cage partially embedded in vertebral body. Three cases of OLIF Stand-alone were treated with pedicle screw fixation via posterior intermuscular approach, while one case of OLIF Stand-alone and four cases of OLIF combined with posterior pedicle screw fixation were not treated specially. RESULTS: The 5 cases of initial operation and 3 cases of reoperation did not show wound skin necrosis or wound infection. The follow-up time was from 12 to 48 months with an average of 22.8 months. Visual analogue scale (VAS) of low back pain was preoperative decreased from 4 to 8 points (averagely 6.3 points) and postoperative 1 to 3 points (averagely 1.7 points) at the final follow-up. Oswestry disability index (ODI) was preoperative 39.7% to 52.4% (averagely 40.2%), and postoperative 7.9% to 11.2% (averagely 9.5%) at the final follow-up. During the follow-up, there was no loosening or fracture of the pedicle screw system, and no lateral displacement of the fusion cage;however, the fusion cage at the vertebral fracture segment had obvious subsidence. The intervertebral space height of vertebral fracture segment was preoperaive 6.7 to 9.2 mm (averagely 8.1 mm), and postoperative 10.5 to 12.8 mm (averagely 11.2 mm). The improvement rate after operation was 37.98% compared to preoperative. The intervertebral space height at final follow-up was 8.4 to 10.9 mm (averagely 9.3 mm), and the loss rate was 16.71% compared with that after operation. At the final follow-up, interbody fusion was achieved in all cases except for one that could not be identified. CONCLUSION The incidence of vertebral fracture during oblique lateral interbody fusion in the treatment of lumbar spondylopathy is lower, and there are many reasons for fracture, including preoperative bone loss or osteoporosis, endplate injury, irregular shape of endplate, excessive selection of fusion cage, and osteophyte hyperplasia at the affected segment. As long as vertebral fracture is found in time and handled properly, the prognosis is well. However, it still needs to strengthen prevention.
Humans ; Female ; Male ; Spinal Fractures/surgery* ; Retrospective Studies ; Treatment Outcome ; Lumbar Vertebrae/surgery* ; Spondylolisthesis/surgery* ; Scoliosis ; Spinal Fusion/methods*

OBJECTIVE: To summarize and compare the endplate injury occurrence characteristics and clinical results of transforaminal intervertebral fusion combined with pedicle screw fixation through intermuscular approach and oblique lateral intervertebral fusion combined with pedicle screw fixation in the treatment of lumbar disease. METHODS: A retrospective analysis of 213 cases of lumbar disease admitted from January 2016 to June 2019, including 73 males and 140 females. The age ranged from 24 to 81 years old, with an average of(54.9±10.5) years old. The courses of disease ranged from 6 to 180 months, with an average of (40.30±28.71) months. There were 35 cases of degenerative lumbar intervertebral disc disease, 22 cases of giant lumbar disc herniation, 15 cases of discogenic low back pain, 9 cases of primary lumbar intervertebral inflammation at the turn of inflammation, 52 cases of lumbar spinal stenosis, 47 cases of lumbar degenerative spondylolisthesis, 33 cases of lumbar spondylolysis with or without spondylolisthesis. There were 191 cases of single-segment lesions, including 5 cases on L2, 3, 24 cases on L3, 4, 162 cases on L4, 5. And there were 22 cases of two-segment lesions, including 3 cases on L2, 3 and L3, 4, and 19 cases on L3, 4 and L4, 5. One hundred and ten cases were taken by bilateral pedicle screw fixation and interbody fusion under the posterior muscle space approach (abbreviated as posterior fusion group), and 103 cases were taken by oblique lateral interbody fusion combined with bilateral pedicle screw fixation under the posterior muscle space approach (oblique lateral fusion group). Observed the characteristics of endplate injury in the two groups, and compared the clinical and imaging results and complications of the two groups. RESULTS: There were 8 cases of endplate injury occurred in 9 segments in the posterior fusion group. According to the number of cases, the incidence rate was 7.27%(8/110), 1 case was male, 7 cases were female, with an average age of (63.22±3.51) years old. Among the 8 cases, there were 7 cases of bone loss or osteoporosis before the operation, 5 cases using banana fusion cages, 3 cases using anatomical fusion cages. Three cases occurred in the upper endplate of the vertebral body and 6 cases in the inferior endplate of the vertebral body. In the oblique lateral fusion group, there were 21 cases of endplate injury in 24 segments, and the incidence rate was 20.39%(21/103). There were 4 males and 17 females, with an average age of (62.50±5.02) years old. Among the 21 cases, 16 cases were bone loss or osteoporosis before operation. There were 5 cases used large fusion cages, 4 cases had abnormal endplate anatomy, and 3 cases had iliac crest hypertrophy. It occurred in 20 segments of the upper endplate of the vertebral body, and 4 segments of the lower endplate of the vertebral body. Two of the 21 cases of endplate injury combined with vertebral body fractures. The incidence of endplate injury of the posterior fusion group was significantly lower than that of the oblique lateral fusion group. No incision infection occurred in the two groups, the follow-up time was ranged from 12 to 48 months, and the median follow-up period was 12 months. In the follow-up, 22 cases occurred fusion cage subsidence in the posterior fusion group, 43 cases in the oblique lateral fusion group, and 1 case in each group occurred fusion cage displacement. There was no loosening, displacement or breakage of the internal fixation. The incidence of complications in the oblique lateral fusion group 33.98%(35/103) was significantly higher than that in the posterior fusion group 23.64%(26/110), P=0.039. The height of the intervertebral space in both groups recovered well after the operation, but it was lost to varying degrees during follow-up. The fusion rate of the posterior fusion group was 94.5%(104/110), and 96.1%(99/103) in the oblique lateral fusion group(P=0.083). At the latest follow-up, the clinical symptoms of the two groups of patients were significantly improved. CONCLUSION Two methods in treating single or two-segment lumbar spine lesions obtained good clinical effects. The characteristics of endplate injury in the two fusion methods are not completely the same. Although the endplate injury did not affect the final clinical results of the two fixed fusion methods, it still needs to be paid attention to and emphasize the prevention and effective treatment of endplate injury, especially for oblique lateral intervertebral fusion.
Humans ; Male ; Female ; Middle Aged ; Aged ; Young Adult ; Adult ; Aged, 80 and over ; Spondylolisthesis/surgery* ; Spinal Fusion/methods* ; Case-Control Studies ; Retrospective Studies ; Lumbar Vertebrae/surgery* ; Spinal Fractures ; Treatment Outcome ; Osteoporosis ; Inflammation