Objective:To investigate the clinical outcomes of minimally invasive lateral lumbar interbody fusion (LLIF) and the necessity to perform LLIF plus posterior direct decompression in the treatment of severe degenerative lumbar spinal stenosis (DLSS).Methods:In this prospective randomized, controlled trial, we assigned 71 patients, who were 50 to 80 years old, and diagnosed with severe DLSS (Schizas Classification grade C on magnetic resonance imaging), in a 1∶1 ratio to undergo either one-stage LLIF plus posterior internal fixation (treatment group) or CLIF plus posterior internal fixation with laminectomy (control group). Demographic and perioperative data were collected and compared. The clinical outcome measures included Oswestry Disability Index (ODI), Zurich Claudication Questionnaire (ZCQ) score as well as visual analogue scale (VAS). Patients were followed up for at least 1 year.Results:The treatment group included 36 patients with 46 surgical levels, while the control group included 35 patients with 46 surgical levels. The baseline demographic data of the 2 groups were equivalent in preoperative central canal areas, spinal canal anteroposterior diameter, disc height, ODI, ZCQ score for symptom severity and physical function, as well as VAS scores for back and leg pain. The mean operative time, blood loss, drainage volume and hospital stay of the treatment group are significantly less than the control group (157.2±29.1 min vs. 180.6±26.8 min, 75.6±39.1 ml vs. 108.6±43.3 ml, 136.9±73.9 ml vs. 220.5±121.3 ml, 5.3±1.1 d vs. 6.6±2.3 d). There were 2 cases with dura tear and 1 case with wound infection in control group. Thus, the surgical trauma and complications of the control group were more than the treatment group. At 1-year follow-up, the mean ODI score of treatment group improved from 42.24%±10.70% preoperatively to 18.21%±11.49%, the mean ZCQ symptom severity from 2.89±0.38 to 1.61±0.41, the mean ZCQ physical function from 2.31±0.45 to 1.50±0.37, the mean VAS for back from 5.56±1.19 to 1.97±1.13 and the mean VAS for leg from 4.44±1.81 to 0.94±1.26. At 1-year follow-up, the mean ODI score of the control group improved from 43.65%±14.93% preoperatively to 17.36%±12.15%, the mean ZCQ symptom severity from 2.92±0.52 to 1.65±0.39, the mean ZCQ physical function from 2.37±0.52 to 1.55±0.39, the mean VAS for back from 5.63±1.40 to 2.34±1.47, and the mean VAS for leg from 4.37±2.14 to 0.83±1.20. The ZCQ satisfactory score of both groups were not significant different (1.25±0.45 vs. 1.26±0.43, t=0.07, P=0.944). The mean improvement rate of both groups for ODI, ZCQ symptom severity, ZCQ physical function, VAS back and VAS leg at 1-year follow-up were not significant different (55.43%±27.74% vs. 58.36%±25.06%, 43.07%±17.22% vs. 42.66%±12.95%, 32.25%±23.65% vs. 31.71%±23.24%, 62.65%±21.25% vs. 58.37%±22.44%, 78.94%±26.41% vs. 85.45%±20.53%). One adjacent segment disease was found in each group at 1 year follow-up. Conclusion:CLIF+ posterior internal fixation in the treatment of Schizas Grade C DLSS has satisfactory clinical outcome at 1-year follow-up. Laminectomy increases surgical trauma, but does not significantly improve the clinical outcome at 1-year follow-up.

With the accelerated aging society in China, the incidence of biliary surgical diseases in the elderly has increased significantly. The clinical characteristics of these patients indicate that improving treatment outcomes and realizing healthy aging are worthy of attention. How to effectively improve the treatment effect of geriatric biliary surgical diseases has attracted widespread attention. This paper reviews and comments on the hotspots and difficulties of biliary surgery in older patients from six aspects: (1) higher morbidity associated with an aging society, (2) prevention and control of pre-operative risks, (3) extending the indications of laparoscopic surgery, (4) urgent standardization of minimally invasive surgery, (5) precise technological progress in hepatobiliary surgery, and (6) guarantee of peri-operative safety. It is of great significance to fully understand the focus of controversy, actively make use of its favorable factors, and effectively avoid its unfavorable factors, for further improving the therapeutic effects of geriatric biliary surgical diseases, and thus benefits the vast older patients with biliary surgical diseases. Accordingly, a historical record with the highest age of 93 years for laparoscopic transcystic common bile duct exploration has been created by us recently.
Humans ; Aged ; Aged, 80 and over ; Biliary Tract Surgical Procedures ; Gallstones ; Laparoscopy ; Treatment Outcome ; Aging ; Retrospective Studies

Objective:To investigate the influence of different degrees of facet joint arthropathy on the indirect decompression effect of crenel lumbar interbody fusion (CLIF), and the clinical outcomes of CLIF for the treatment of lumbar spinal stenosis with severe facet joint arthropathy (grade 3).Methods:This study reviewed a total of 269 surgical segments in 156 patients with lumbar spinal stenosis treated with CLIF technique from November 2016 to February 2020. According to preoperative CT images, the facet joint was graded according to Pathria classification. There are 19 segments with grade 0, 156 segments with grade 1, 67 segments with grade 2, and 27 segments with grade 3. Radiographic parameters included disc angle, anterior and posterior disc height, and bilateral intervertebral foramen height on CT, and the midsagittal canal diameter and axial central canal area. In 30 patients with at least one segment of grade 3, the clinical efficacy was assessed using visual analogue scale (VAS) and Oswestry disability index (ODI).Results:The average the anterior and posterior intervertebral space height, intervertebral space angle, height of bilateral intervertebral foramina, spinal canal sagittal diameter and spinal canal area were significantly improved after the operation of grade 3 facet joint degeneration segment compared to preoperation. The preoperative mean spinal canal sagittal diameter and spinal canal area of grade 3 facet joint degeneration segment were significantly less than grade 1 and grade 2. The average change of spinal canal area after grade 3 articular degeneration was significantly less than that of grade 1 and 2, but there was no significant difference with that of grade 0. The posterior decompression rate was 55.56% (15/27) for grade 3, 35.82% (24/67) for grade 2, 16.03% (25/156) for grade 1, and 21.05% (4/19) for grade 0. The posterior decompression rate of grade 3 articular process degeneration was significantly higher than that of other grades ( P<0.001). Severe lateral recess stenosis and 24.24% of severe intervertebral foraminal stenosis were found in 81.48% of grade 3 degenerative segment. The 23 patients were followed up with an average of 21.62±6.52 months, and the average improvement of ODI was 24.10%±11.09%; the average VAS for leg pain and back pain were improved significantly. Conclusion:The degrees of facet joint degeneration do not prevent intervertebral space distraction of CLIF. However, because segments with severe facet joint arthropathy were usually associated with severe spinal canal stenosis, CLIF had a high rate of second-stage posterior decompression in the treatment of lumbar spinal stenosis with severe facet joint arthropathy.

Objective:To investigate the changes of paraspinal muscles in patients with degenerative lumbar scoliosis (DLS) and its correlation with lumbar kyphosis.Methods:The clinical data of 67 female patients with degenerative lumbar scoliosis, with an average of 65.4±5.6 years old (rang 52-83 years old), were retrospectively analyzed. There were 35 patients of DLS with lumbar degenerative kyphosis (LDK) in the DLS+LDK group, with an average of 64.60±5.40 years old (rang 52-75 years old), and 32 patients of lumbar scoliosis without lumbar kyphosis in the DLS group, with an average of 66.22±5.8 years old (rang 55-83 years old). The cross-sectional area (CSA) and the percentage of fat infiltration area (FIA%) of erector spinae and multifidus muscles of the 5 intervertebral disc levels (from L 1-2 to L 5S 1) were measured by MRI using Image J software (ver. 1.51 k, National Institutes of Health, USA). The curve direction, Cobb angle, sagittal vertical axis (SVA), thoracic kyphosis (TK), thoracolumbar kyphosis (TLK), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT) and sacral slope (SS) were evaluated and recordedin both groups using an anteroposterior radiograph in the standing position, and the correlation between the changes of paraspinal muscles and these factors was analyzed. Results:The TLK, LL, and SVA values of the DLS+LDK group (11.85°±7.89°, -9.35°±8.70° and 70.16±76.94 mm) were higher than those of the DLS group (7.47°±5.06°, -26.46°±10.26° and 39.45±38.18mm) ( t=2.73, P=0.008; t=7.38, P<0.001; t=2.10, P=0.041). The TK, PI, and SS values of the DLS+LDK group (16.36°±13.52°, 42.49°±11.70° and 11.89°±10.03°) were lower than those of the DLS group (23.60°±10.23°, 49.38°±11.92° and 21.21°±8.28°) ( t=2.45, P=0.017; t=2.38, P=0.020; t=4.13, P<0.001). The differences of Cobb and PT were not statistically significant between the two groups. The cross-sectional areas of L 1-2, L 2-3, L 3-4 intervertebral disc levels of erector spinae of the DLS+LDK group (1 328.36±339.16 mm 2, 1 331.98±305.76 mm 2 and 12 53.58±275.86 mm 2) were lower than those of the DLS group (1 564.16±312.68 mm 2, 1 574.80±325.92 mm 2 and 1 427.18±278.82 mm 2) ( t=0.40, P=0.004; t=0.81, P=0.002; t=0.306, P=0.013). The cross-sectional areas of L 1-2, L 2-3, L 3-4, L 4-5 intervertebral disc levels of multifidus muscles of the DLS+LDK group (225.07±59.80 mm 2, 228.38±87.44 mm 2, 436.40±117.99 mm 2 and 666.55±184.13 mm 2) were lower than those of the DLS group (264.28±44.27 mm 2, 384.85±75.52 mm 2, 576.10±109.92 mm 2 and 801.52±145.83 mm 2) ( t=0.21, P=0.004; t=0.42, P<0.001; t=0.52, P<0.001; t=0.37, P=0.002). The differences of FIA% of erector spinae and multifidus muscles at all lumbar spine levels were not statistically significant between the two groups. The cross-sectional areas of L 1-2, L 2-3, L 3-4 intervertebral disc levels of erector spinae and L 1-2, L 2-3, L 3-4, L 4-5 intervertebral disc levels of multifidus muscles of the two groups were negatively correlated with LL values ( r=-0.37, P=0.002; r=-0.34, P=0.005; r=-0.21, P=0.049; r=-0.34, P=0.005; r=-0.61, P<0.001; r=-0.65, P<0.001; r=-0.55, P<0.001), and positively correlated with SS ( r=0.42, P<0.001; r=0.37, P=0.002; r=0.27, P=0.027; r=0.38, P=0.001; r=0.53, P<0.001; r=0.46, P<0.001; r=0.42, P<0.001). The cross-sectional areas of L 3-4 intervertebral disc levels of erector spinae and L 1-2, L 2-3 intervertebral disc levels of multifidus muscles of the two groups were positively correlated with PI ( r=0.25, P=0.039; r=0.33, P=0.006; r=0.35, P=0.004). There was no correlation between the FIA% of erector spinae and multifidus muscles at all lumbar spine levels and the sagittal and pelvic parameters in both groups. Conclusion:Paravertebral muscle atrophy is more obvious in patients with degenerative lumbar scoliosis with lumbar kyphosis, which may be related to the reduce of lumbar lordosis and sacral slope. Patients with lumbar scoliosis with a smaller PI are more likely to experience paravertebral atrophy and increased loss of lumbar lordosis, and ultimately leading to lumbar kyphosis.

Objective:To understand the common viral infection among the surveillance cases of fever respiratory syndrome (FRS) in nine provinces in China.Methods:The research data were obtained from nine provinces (Anhui, Beijing, Guangdong, Hebei, Hunan, Jilin, Shandong, Shaanxi and Xinjiang) in the "Infectious Disease Surveillance Technology Platform Information Management System" of the Chinese Center for Disease Control and Prevention from January 2009 to June 2021. Finally, 8 243 FRS cases with nucleic acid detection results of eight viruses [human influenza virus (HIFV), human respiratory syncytial virus (HRSV), human adenovirus (HAdV), human parainfluenza virus (HPIV), human rhinovirus (HRV), human metapneumovirus (HMPV), human coronavirus (HCoV) and human Boca virus (HBoV)] were included in the study. The χ 2 test/Fisher exact probability method was used to analyze the difference of virus detection rate in different age groups, regions and seasons. Results The M ( Q1, Q3) age of 8 243 FRS cases was 4 (1, 18) years old, and 56.56% (4 662 cases) were children under 5 years old. Males accounted for 58.1% (4 792 cases) of all cases. All cases were from outpatient/emergency department (2 043 cases) and inpatient department (6 200 cases). The virus detection rates of FRS cases from high to low were HRSV, HIFV, HPIV, HRV, HAdV, HMPV, HCoV and HBoV. Two or more viruses were detected simultaneously in 524 cases, accounting for 15.66% of virus-positive cases. The difference of the virus detection rate in different age groups was statistically significant (all P values<0.05), and the virus detection rate in children<5 years old was higher (49.96%). The positive rate of any virus in south China was higher than that in north China ( P<0.001). The virus-positive FRS cases were detected throughout the year. The detection rate of HRSV was higher in autumn and winter. The detection rate of HIFV was higher in winter. The detection rate of HMPV was higher in winter and spring. The detection rates of HPIV, HRV, HCoV and HBoV were higher in summer and autumn, while there was no significant difference in the detection rate of HAdV in different seasons. Compared with 2009-2019, the detection rate of any virus in 2020-2021 decreased from 41.37% to 37.86%. The detection rate of HIFV decreased sharply from 10.62% to 1.37%. The detection rate of HPIV decreased from 8.24% to 5.88%. The detection rate of HRV and HBoV increased from 5.43% and 1.79% to 9.67% and 3.19%, respectively. Conclusion:HRSV and HIFV infections are more common among FRS cases in nine provinces in China from 2009 to 2021, and the epidemiological characteristics of eight common respiratory viruses vary in different age groups, regions and seasons.

Objective:To understand the common viral infection among the surveillance cases of fever respiratory syndrome (FRS) in nine provinces in China.Methods:The research data were obtained from nine provinces (Anhui, Beijing, Guangdong, Hebei, Hunan, Jilin, Shandong, Shaanxi and Xinjiang) in the "Infectious Disease Surveillance Technology Platform Information Management System" of the Chinese Center for Disease Control and Prevention from January 2009 to June 2021. Finally, 8 243 FRS cases with nucleic acid detection results of eight viruses [human influenza virus (HIFV), human respiratory syncytial virus (HRSV), human adenovirus (HAdV), human parainfluenza virus (HPIV), human rhinovirus (HRV), human metapneumovirus (HMPV), human coronavirus (HCoV) and human Boca virus (HBoV)] were included in the study. The χ 2 test/Fisher exact probability method was used to analyze the difference of virus detection rate in different age groups, regions and seasons. Results The M ( Q1, Q3) age of 8 243 FRS cases was 4 (1, 18) years old, and 56.56% (4 662 cases) were children under 5 years old. Males accounted for 58.1% (4 792 cases) of all cases. All cases were from outpatient/emergency department (2 043 cases) and inpatient department (6 200 cases). The virus detection rates of FRS cases from high to low were HRSV, HIFV, HPIV, HRV, HAdV, HMPV, HCoV and HBoV. Two or more viruses were detected simultaneously in 524 cases, accounting for 15.66% of virus-positive cases. The difference of the virus detection rate in different age groups was statistically significant (all P values<0.05), and the virus detection rate in children<5 years old was higher (49.96%). The positive rate of any virus in south China was higher than that in north China ( P<0.001). The virus-positive FRS cases were detected throughout the year. The detection rate of HRSV was higher in autumn and winter. The detection rate of HIFV was higher in winter. The detection rate of HMPV was higher in winter and spring. The detection rates of HPIV, HRV, HCoV and HBoV were higher in summer and autumn, while there was no significant difference in the detection rate of HAdV in different seasons. Compared with 2009-2019, the detection rate of any virus in 2020-2021 decreased from 41.37% to 37.86%. The detection rate of HIFV decreased sharply from 10.62% to 1.37%. The detection rate of HPIV decreased from 8.24% to 5.88%. The detection rate of HRV and HBoV increased from 5.43% and 1.79% to 9.67% and 3.19%, respectively. Conclusion:HRSV and HIFV infections are more common among FRS cases in nine provinces in China from 2009 to 2021, and the epidemiological characteristics of eight common respiratory viruses vary in different age groups, regions and seasons.

Objective:To explore the clinical effect of the application of intraoperative psoas major intramuscular block therapy on the complications related to the approach after multi-segmental crenel lumbar interbody fusion (CLIF).Methods:All of 68 degenerative lumbar scoliosis patients who had received multi-segmental crenel lumbar interbody fusion during January 2020 and June 2020 were retrospectively reviewed. Patients were divided into two groups according to whether the psoas major muscle was treated with block therapy during the operation. The psoas muscle inblock group were filled with gel sponge infiltrated with a mixture of Betamethasone and lidocaine for local block therapy before closing the incision while that in the control group were not filled with gel sponge. There were 33 patients in the control group, 7 males and 26 females with an average of 65.8±7.1 years old (range: 54-81 years old); 35 cases in the block group, 9 males and 26 females with an average of 68.0±6.5 years old (range: 54-85 years old). The complications related to the approach (mainly includes pain, numbness in the front of the thigh, as well as psoas major, quadriceps muscle strength) were recorded respectively 1 day, 1 week, 1 month and 3 months after surgery. The main indicators of outcome including visual analog scale (VAS) of pain, the visual analog scale (VAS) of numbness, muscle strength of psoas major and quadriceps femoris, and the incidence of complications related to the approach were compared between the two groups of patients at different time points after surgery. The clinical outcomes were assessed using the Oswestry disability index (ODI), VAS for low back pain. The radiological outcome was evaluated with Cobb angles and sagittal balance parameters (sagittal vertical axis, SVA).Results:There were no significant differences in age, gender, body mass index (BMI), number of fusion segments, operation time, and intraoperative blood loss between the two groups. The incidence of approach-related complications was 17.1% in the block group and 39.4% in the control group, with statistically significant difference between the two groups ( χ2=4.177, P=0.041). The incidence of postoperative pain, numbness in the front of the thighs, and muscle strength of psoas major in the block group (11.4%, 14.3%) were lower than those in the control group (33.3%, 36.4%) ( χ2=4.740, P=0.029; χ2=4.416, P=0.036). And for numbness in the front of thigh, the block group (14.3) was lower than control group (21.2%), but no significant difference was shown between two groups ( χ2=0.561, P=0.454). However, there was no quadriceps weakness in either group. The VAS scores of painof the block group were lower than those of the control group at 1 day, 1 week, and 1 month after surgery, and the difference was statistically significant ( t=2.220, P=0.031; t=2.235, P=0.031; t=2.086, P=0.044). The difference at 3 months was not statistically significant ( t=0.385, P=0.701). The muscle strength of psoas major of the block group, meanwhile, was higher than those of the control group on the 1day and 1 week after surgery, the difference was statistically significant as well ( t=2.208, P=0.032; t=2.171, P=0.034). The difference at 1 and 3 months was not statistically significant ( t=0.923, P=0.359; t=1.437, P=0.160). No statistically significant differences were found in VAS scores of numbness at 1 day, 1 week, 1 month, and 3 months after surgery. Postoperative low back pain and lumbar spine function were significantly improved in both groups, and there was no statistical significance between the two groups. Coronal Cobb angle and sagittal balance were significantly improved in both groups after surgery, and there was no statistical significance between the two groups. Conclusion:Psoas major intramuscular block therapy can reduce the incidence of early postoperative complications of multi-segmental CLIF. Furthermore, it was found to be effective to alleviate anterior thigh pain within 1 month, and improve psoas major muscle weakness within 1 week.

Objective:To understand the genetic characteristics of subgenus C human adenovirus (HAdV-C) strain isolated in Hunan in 2014.Methods:An HAdV-C strain named Hunan2014-s024 was isolated from throat swab collected from a child with severe acute respiratory infection in Changsha city of Hunan province in 2014. The whole genome sequence (WGS) was obtained by segmented amplification and sequence splicing. Database of HAdV-C was constructed with the strain from this study and the HAdV-C representative strains from GenBank. The whole genome characteristics was analyzed by using bioinformatics software.Results:Strain Hunan2014-s024 has the highest homology with the HAdV-C strain (MK041244-CHN-2006) isolated from stool sample of a healthy child in Shanxi province in 2006, and the genome of strain MK041244-CHN-2006 was used as the backbone, and penton based gene was replaced by gene fragment from MK041246-chn-2012 strain isolated from a child with acute lower respiratory tract infection in Hunan province in 2012.Conclusions:Our result indicated that 2014 Hunan strain(Hunan2014-s024)is a recombinant virus of 2006 Shanxi strain(MK041244-CHN-2006)and 2012 Hunan strain(MK041246-CHN-2012). Due to the change of pathogenicity, it is necessary to strengthen the molecular epidemiological surveillance of HAdV-C to understand its potential disease burden and public health significance.

Objective: To investigate the preliminary clinical efficacy of modified minimally invasive lateral interbody fusion in the anterior support and reconstruction for thoracolumbar fracture combined with intervertebral disc injury. Methods: A retrospective case series study was conducted to analyze the clinical data of 14 patients with single-segment thoracolumbar fracture combined with intervertebral disc injury admitted to the Second Affiliated Hospital of Zhejiang University School of Medicine from December 2017 to May 2018. There were 12 males and two females, aged 22-56 years [(37.4±10.2)years]. The injured segments were at L₁ in nine patients and L₂ in five patients. Twelve patients had upper disc injury and two patients had lower disc injury. Before operation, American Spinal Injury Association (ASIA) classification was grade A in five patients, grade B in four, grade C in three, and grade D in two. All patients received modified minimally invasive lateral interbody fusion to reconstruct the stability of the anterior and middle columns of the spine one week after posterior short-segment fixation. The operation time, intraoperative bleeding, postoperative hospital stay and complications were recorded. Pain visual analogue scale (VAS) and ASIA nerve injury grading were used to evaluate the clinical efficacy. The Cobb angle changes of the operative segment and lumbar lordosis were compared before operation and during the last follow-up. Results: The patients were followed up for 6-14 months[(12.1±3.6)months]. The operation time was 65-210 minutes [(138.9±39.4)minutes], and the intraoperative blood loss was 250-600 ml [(407.1±119.1)ml], respectively. The total postoperative length of stay ranged from 3 to 13 days [(7.8±2.5)days]. The incisions healed well at stage I in all patients. VAS for back pain and leg pain before operation were (6.3±2 .4)points and (4.1±1.3)points respectively. The final VAS for back pain and leg pain were (2.2±0.6)points and (2.3±0.8)points, which were significantly lower than the preoperative VAS (both P<0.01). At the last follow-up, there was one patient with grade A, two with grade B, five with grade C, one with grade D, and five with grade E. Postoperative CT showed that decompression was complete, implants were in good position and internal fixation was reliable. Preoperative Cobb angles of lumbar lordosis and the injury segment were (-7.8±3.9)° and (24.8±6.9)° respectively. The final Cobb angles of lumbar lordosis and the injury segment were (3.1±2.7)° and (30.7±9.6)°, which were significantly restored compared with preoperative values (both P<0.01). One patient had postoperative pain in the front thigh, and another patient had numbness in the front thigh, whose symptoms were alleviated after non-surgical treatment. No serious surgical complications such as quadriceps femoris and weakness, pleural tear, vascular injury, nerve root injury, sympathetic nerve injury, retroperitoneal hematoma and artificial vertebral body displacement occurred in these patients. Conclusions For anterior reconstruction of the thoracolumbar fracture with intervertebral disc injury, the modified minimally invasive lateral interbody fusion has the advantages of less invasive, less blood loss, shorter hospitalization time, low incidence of complications. Significant pain relief, neurological function improvement, and anterior and middle column reconstruction can be achieved postoperatively.

Objective To explore the impact of cage position on indirect decompression and cage subsidence in crenel lateral interbody fusion (CLIF).Methods Retrospectively,18 mens and 16 womens with a mean age of 63.98±5.99 years (range:52-75 years) who underwent CLIF for lumbar stenosis by our surgical group during November 2016 and Feburary 2018 were reviewed.Sixty-two segments were included for radiographic evaluation.Endplates thickness was measured using high resolution computed tomography.By image processing,endplate thickness was measured at 10 equally distributed points on the mid-sagittal and mid-coronal planes,and two further planes were measured at an angle of 45° to both the first and second planes.Contour plots representing an isoline of endplate thickness was drawn based on those data.The cages were classified into anterior group and medium-posterior group.Radiographic evaluation included segmental angle,anterior and posterior disk heights,intervertebral foramen heights,and cross-sectional area of the spinal canal.To assess the factors affecting the postoperative segmental angle and cross-sectional area of the spinal canal,univariate and multivariate analysis were performed using the regression analysis model.Cage subsidence was recorded at the last follow-up.Results The mean follow-up time of those patients were 10.88±3.73 months (range:6-18 months).At each spot,the mean thickness was significantly greater for the cranial endplate of disc than the caudal endplate.Contour plots show more areas of thick bony endplates in the anterior and anterolateral part of the endplate than the lateral and posterior part,especially for the cranial endplate.The cage was placed in the anterior area for 19 levels and medium-posterior for 41 levels.The mean increase of anterior disk height was 3.38±3.38 mm in anterior group and 1.83±3.08 mm in medium-posterior group(P=0.04).The mean increase of segmental angle was 2.93°±3.47°in anterior group and 0.73°±3.60° in medium-posterior group(P=0.04).No significant difference was found with mean increase of posterior disk height,mean increase of intervertebral foramen heights,as well as increase ratios of cross-sectional area of the spinal canal between groups.Multivariate analysis showed that the increase of segmental angle was affected by cage position (β=1.24,P=0.03),but the increase ratios of cross-sectional area of the spinal canal was not affected.The subsidence rate of anterior group was 15.79％ (3/19) and medium-posterior group was 24.39％ (10/41),which was not significantly different (x2=0.56,P=0.45).Conclusion There are more areas with thick bony endplates in the anterior and anterolateral parts of the lumbar endplate than the lateral and posterior parts.The cage position at the anterior 1/3 of disk space is better for achieving the restoration of the segmental angle and having lower subsidence rate,without compromising the indirect neural decompression in crenel lateral interbody fusion.