Objectives:To investigate the clinical efficacy of unilateral biportal endoscopy (UBE) in the treatment of degenerative lumbar disease (DLD) and its impact on postoperative lumbar stability.Methods:This is a retrospective case series study. A total of 109 cases of DLD treated with UBE in the Department of Orthopaedic, Beijing Chaoyang Hospital Affiliated to Capital Medical University from July 2020 to June 2022 were analyzed retrospectively. There were 47 males and 62 females, aged (53.3±8.2) years (range: 21 to 80 years). The surgical segments were single segment in 80 cases, two segments in 25 cases, and three segments in 4 cases. The low back pain and leg pain of visual analogue scale (VAS), Japanese Orthopaedic Association (JOA) score and Oswestry disability index (ODI) were evaluated before and after operation. The modified MacNab criteria were used for evaluation of the clinical consequences. Postoperative three-dimensional lumbar CT was performed to observe the preservation of the facet joints and the angle of the medial surface of the facetectomy(β angle). At 12 months after surgery, X ray of the flexion and extension lumbar spine were reviewed. The comparison and analysis of the data were conducted using paired sample t tests or generalized estimation equations. Results:All 109 patients underwent operative procedures successfully. The operation time was (94.5±37.1) minutes (range:56 to 245 minutes), the times of X ray was 6.8±4.0 (range:4 to 16 times), and the days of hospitalization was (5.3±3.7) days (range:4 to 14 days). Complications included dural tears in 4 cases, transient lower limb numbness in 4 cases, epidural hematoma in 2 case. The follow-up time was (19.6±7.2) months (range:12 to 36 months). The postoperative low back pain VAS, leg pain VAS, JOA score and ODI were significantly improved(all P<0.05). According to the modified MacNab criteria, the excellent and good rate was 88.99%(97/109) at 12 months after surgery. One case underwent revision surgery because of recurrent lumbar disc herniation. In term of radiographic evaluation, the area of the surgical side facet joints after UBE surgery was reserved more than 60%. The β angle was less than 90° in all patients. After 12 months of surgery, there was no surgical segment instability or spondylolisthesis by the X-ray of the flexion and extension lumbar spine. Conclusion:UBE can achieve satisfactory clinical efficacy in the treatment of DLD, and maintain the stability of the lumbar spine.

Objectives:To investigate the clinical efficacy of unilateral biportal endoscopy (UBE) in the treatment of degenerative lumbar disease (DLD) and its impact on postoperative lumbar stability.Methods:This is a retrospective case series study. A total of 109 cases of DLD treated with UBE in the Department of Orthopaedic, Beijing Chaoyang Hospital Affiliated to Capital Medical University from July 2020 to June 2022 were analyzed retrospectively. There were 47 males and 62 females, aged (53.3±8.2) years (range: 21 to 80 years). The surgical segments were single segment in 80 cases, two segments in 25 cases, and three segments in 4 cases. The low back pain and leg pain of visual analogue scale (VAS), Japanese Orthopaedic Association (JOA) score and Oswestry disability index (ODI) were evaluated before and after operation. The modified MacNab criteria were used for evaluation of the clinical consequences. Postoperative three-dimensional lumbar CT was performed to observe the preservation of the facet joints and the angle of the medial surface of the facetectomy(β angle). At 12 months after surgery, X ray of the flexion and extension lumbar spine were reviewed. The comparison and analysis of the data were conducted using paired sample t tests or generalized estimation equations. Results:All 109 patients underwent operative procedures successfully. The operation time was (94.5±37.1) minutes (range:56 to 245 minutes), the times of X ray was 6.8±4.0 (range:4 to 16 times), and the days of hospitalization was (5.3±3.7) days (range:4 to 14 days). Complications included dural tears in 4 cases, transient lower limb numbness in 4 cases, epidural hematoma in 2 case. The follow-up time was (19.6±7.2) months (range:12 to 36 months). The postoperative low back pain VAS, leg pain VAS, JOA score and ODI were significantly improved(all P<0.05). According to the modified MacNab criteria, the excellent and good rate was 88.99%(97/109) at 12 months after surgery. One case underwent revision surgery because of recurrent lumbar disc herniation. In term of radiographic evaluation, the area of the surgical side facet joints after UBE surgery was reserved more than 60%. The β angle was less than 90° in all patients. After 12 months of surgery, there was no surgical segment instability or spondylolisthesis by the X-ray of the flexion and extension lumbar spine. Conclusion:UBE can achieve satisfactory clinical efficacy in the treatment of DLD, and maintain the stability of the lumbar spine.

Objective:To investigate the risk factors for proximal junctional kyphosis (PJK) in adult spinal deformity patients with concomitant osteoporosis undergoing long-segment spinal fusion surgery.Methods:A retrospective analysis was conducted on 76 adults spinal deformity patients with osteoporosis who underwent long-segment spinal fusion surgery at the Department of Orthopaedics, Beijing Chaoyang Hospital, between June 2013 and December 2019. The cohort included 19 males and 57 females, with a mean age of 66.26±6.10 years (range, 54-78 years). Patients were categorized into two groups based on the occurrence of PJK within a 2-year postoperative follow-up: the PJK group (21 cases) and the non-PJK group (55 cases). Comparative analyses were performed on baseline characteristics, surgical details, preoperative and postoperative spinal-pelvic parameters, Hounsfield Units (HU) of the vertebral bodies, and paraspinal muscle morphology between the groups. Spinal-pelvic parameters included the main Cobb angle, lumbar lordosis (LL), lumbosacral lordosis (LSL), sagittal vertical axis (SVA), T 1 pelvic angle (TPA), pelvic tilt (PT), sacral slope (SS), and pelvic incidence (PI). Preoperative CT was used to measure HU values at the upper instrumented vertebra (UIV), UIV+1, and UIV+2. Paraspinal muscle morphology, including the relative functional cross-sectional area (rFCSA) and functional muscle-fat index (FMFI) at the L 4 lower endplate level, was assessed using preoperative MRI. Optimal cutoff values for HU and paraspinal muscle parameters were determined using receiver operating characteristic curve analysis. Multivariable logistic regression was employed to identify independent risk factors for PJK. Results:Significant differences were observed between the PJK and non-PJK groups in preoperative PT (17.60°±8.39° vs. 24.12°±9.37°), postoperative LL (35.61°±10.62° vs. 42.22°±13.11°), LSL (30.24°±10.10° vs. 35.87°±11.12°), and SVA (37.82°±20.46° vs. 21.37°±17.35°). The differences were statistically significant ( P<0.05). The HU values of UIV (113.62±17.25 vs. 133.94±16.61), UIV+1 (123.14±16.03 vs. 138.27±13.69), and UIV+2 (121.00±15.91 vs. 134.47±15.53) were significantly lower in the PJK group ( P<0.05). Optimal cutoff values for HU at UIV, UIV+1, and UIV+2 were identified as 120.72, 127.51, and 121.50, respectively. Significant differences were also found in rFCSA (156.87±48.06 vs. 204.87±50.16) and FMFI (0.31±0.10 vs. 0.23±0.09). The differences were statistically significant( P<0.05), with optimal cutoff values of 175.43 for rFCSA and 0.24 for FMFI. Multivariable logistic regression analysis indicated that postoperative SVA [ OR=1.049, 95% CI (1.003, 1.097), P=0.037], HU of UIV [ OR=0.938, 95% CI (0.887, 0.991), P=0.024], and rFCSA of paraspinal muscles [ OR=0.883, 95% CI (0.792, 0.983), P=0.023] were independent risk factors for PJK. Conclusion:Reduced HU values of the UIV, decreased rFCSA of lumbar paraspinal muscles, and inadequate sagittal alignment correction are independent risk factors for PJK in adult spinal deformity patients with osteoporosis undergoing long-segment spinal fusion surgery.

Objective: To analyze the risk factors of implant-related complications in adult patients with adult degenerative scoliosis (ADS) who underwent long-level internal fixation. Methods: This was a retrospective study that analyzed 99 cases of adult degeneration scoliosis patients who underwent long level posterior pedicle screw fixation in our hospital between June 2013 and January 2016. The internal fixation and related complications were evaluated by measuring and analyzing the radiographic data of the postoperative X-ray films. The timepoints of measurement were pre-operation, before discharge, half a year, 1 year, when complications occur and the final follow-up after operation. Implant-related complications included proximal junctional kyphosis (PJK), proximal junctional failure (PJF), distal junctional kyphosis/failure (DJK/DJF), rod breakage in addition to other radiographic implant-related complications (that were not related to PJF) such as screw loosening, breakage or pullout, or interbody graft and hook or set screw dislodgements seen on follow-up radiographs. The incidence of postoperative implant-related complications was counted. All the cases included in the study were divided into the complication group and the non-complication group. Statistical difference between groups at different follow-up time point was analyzed. Potential risk factors were identified using univariate testing. Multivariate Logistics regression was used to analyze the independent risk factors for implant-related complications. The postoperative functional scores were assessed using the Oswestry Disability Index (ODI), Japanese Orthopaedic Association Scores (JOA), Visual Analogue Scale (VAS), and Lumbar Stiffness Disability Index (LSDI). Functional scores were tested using group t tests. Patients were divided into groups according to PI-LL <10 °, 10°-20 ° and > 20 °. The preoperative and postoperative radiographical parameters and clinical function score among each groupwere compared.The best PI-LL matching value was verified by analyzing the effect of long-segment fusion orthopedics on ADS. Results: Ninety-nine ADS patients who underwent long level posterior fixation were included. The incidence of patients with mechanical complications was 30.3%. Univariate analysis showed that chronic risk factors of postoperative implant-related complications after surgery of ASD included diabetes (OR=3.52, P=0.001) and blood transfusion (OR=2.61, P=0.030); surgical risk factor isosteotomy (OR=4.33, P=0.000); preoperative imaging risk factor was preoperative SVA (OR=1.03, P=0.000); the risk factors for increased risk of the implant-related complications included anemia (OR=1.17, P=0.810), cardiac complications (OR=1.80, P=0.290) and hospital stay (OR=1.11, P=0.110). Independent predictors identified on multivariate Logistics regression modeling included osteotomy (OR=3.05, P=0.032), and preoperative SVA (OR=1.03, P=0.007). The radiographical parameters and clinical function scores of the PI-LL 10°-20° group were better than or partially superior to those of the PI-LL<10° group and the PI-LL>20° group. The postoperative SVA of the PI-LL 10°-20° group was significantly lower than that of the PI-LL<10° group (t=2.399, P=0.020) and the PI-LL>20° group (t=-3.074, P=0.005). The incidence of implant-related complications in the PI-LL 10°-20° group was significantly lower than that in the PI-LL<10° group (t=1.584, P=0.003). Survival analysis showed that the PI-LL 10°-20° group was significantly better than the PI-LL<10° group (χ²=7.782, P=0.005), while the PI-LL 10°-20° group had better survival than PI-LL>20° group, althoughthatwas not statistically significant (χ²=2.542, P=0.111). Conclusion Risk factors of postoperative implant-related complications after surgery of ASD included osteotomy and preoperative SVA. Patients with one or more of these risk factors should be informed of the risk increase with informed consent. Patients with PI-LL between 10 ° and 20 ° had better postoperative radiographical parameters and clinical functional scores. They should be optimized preoperatively and followed up closely during the postoperative period.

Objective To explore the relationship between positive rate of de novo donor specific antibody (dnDSA ) and human leukocyte antigen (HLA ) mismatch after kidney transplantation and explore the impact of dnDSA upon long-term graft survival and rejection .Methods Retrospective analysis was conducted for clinical data of 101 kidney transplant recipients .Based upon HLA antibody and dnDSA ,they were divided into three groups of HLA-(n=70) ,dnDSA- (n=23) and dnDSA+(n=8) .Rejection and graft survival were recorded for evaluating the impact of dnDSA on rejection and graft survival and observing the differences among all groups .Results The mismatchs of HLA-A/B and HLA-DR were more frequent than HLA-and dnDSA-groups(P=0 .047 , P=0 .010)and graft survival was lower in dnDSA+ group than HLA-and dnDSA-groups (P=0 .001) .The rejection rate was higher in dnDSA+ group (62 .5％ ) than HLA- group (8 .57％ ) and dnDSA-group (8 .69％ ) . The difference was statistically significant (P=0 .013) . Pathological examination indicated microcirculatory inflammation (glomerulonephritis & trichodangiitis ) and damage (multilayer change of capillary basement membrane) occurred frequently in dnDSA + group and C4d remained positive . However ,scar ,arterial fibrosis or tubulointerstitial inflammation was not correlated with dnDSA . Conclusions HLA mismatch is correlated with dnDSA positivity . And dnDSA may reduce graft survival and enhance rejection rate . Rejection mediated by dnDSA is often accompanied by microcirculatory inflammation and C4d positivity .

Objective: To study the clinical results of Coflex and lumbar posterior decompression and fusion in the treatment of lumbar degenerative spondylolisthesis at L_4-5. Methods: Thirty-eight patients with Grade Ⅰ degenerative spondylolisthesis, from January 2008 to December 2011 in Beijing Chaoyang Hospital, Capital Medical University were reviewed, and patients were divided into two groups by randomness. Group A was treated with Coflex and group B with pedicle instrumentation and interbody fusion. Fifteen patients were included in group A, and 23 patients were included in group B. In group A, the average age was (56.3±9.1) years. In group B, the average age was (58.2±11.2) years. The clinical results were evaluated by visual analogue scale (VAS) and Oswestry disability index (ODI). Slip distance (SD) was measured before and after surgery, and the changes of intervertebral angle at index level and adjacent level were also recorded. Results: The follow-up period was 36 to 68 months, with the average of (39±14) months in the both groups. The operation time and bleeding volume of patients in group A were significantly less than that of group B (P<0.05). In both groups, the difference of ODI and VAS before operation and postoperative follow-up were statistically significant (P<0.05). There was no significant difference between lumbar intervertebral angle and the sliding distance in group A at all time points. In the group B, there was a significant increase in the intervertebral angle and the sliding distance at L_3-4 and L₅-S₁ level after surgery, the difference at upper and below adjacent segment before and after surgery were statistically significant. Conclusions Coflex interspinous dynamic stabilization system has same excellent clinical results as pedicle screw instrumentation and fusion surgery for the treatment of L_4-5 degenerative spondylolisthesis; no significant progression of spondylolisthesis been observed during more than 3 years follow-up, and no obvious adjacent segment degeneration has been found.

Objective: To evaluate the influence of PI-LL (pelvic incidence minus lumbar lordosis mismatch) on scoliosis correction, living quality and internal fixation related complications for adult degenerative scoliosis (ASD) after long posterior instrumentation and fusion. Methods: A total of 79 patients with ADS underwent long posterior instrumentation and fusion in the Department of Orthopedics at Beijing Chao Yang Hospital from January 2010 to January 2014 were retrospectively reviewed.There were 21 males and 58 females aging from 55 to 72 years with the mean age (63.4±4.8)years. The patients were divided into three groups according to immediately postoperative PI-LL: PI-LL<10°, 10°≤PI-LL≤20°, PI-LL>20°.Compare the Cobb′s angles, PI-LL, Japanese Orthopaedic Association (JOA) score, Oswestry Disability Index (ODI), Visual Analog Scale (VAS) and Lumbar Stiffness Disability Index (LSDI). Measurement data were compared via t test and ANOVA, enumeration data were compared via Kruskal-Wallis test, noncontiguous data was performed by χ² test. Univariate linear regression equation was performed to investigate the relative influences of postoperative PI-LL on postoperative radiographic parameters and clinical outcome. Results: All the operations were successful without intraoperative complications. The operation time was 145-310 minutes (235.3±42.0) minutes, the intraoperative blood loss was 300-5 300 ml (1 021±787) ml, the duration of hospital was 12-18 d (14.5±1.3) d. A total of 4 to 10 (7.0±1.1) vertebra levels were fused. Compared to preoperative, the Cobb′s angle of scoliosis ((4.2±1.8)° vs. (20.1±2.7)°), PI-LL ((16.1±8.6)° vs. (36.0±4.3)°), JOA (3.0±1.3 vs. 5.5±1.2), ODI (24.4±8.1 vs. 62.9±2.7), VAS (3.0±1.0 vs. 6.8±1.3) were significantly decreased postoperative (t=18.539~53.826, P<0.01). Compared to preoperative, postoperative Cobb′s angle of scoliosis ((4.1±2.7)° vs. (19.5±2.7)°, (4.0±1.4)° vs. (20.2±2.4)°, (4.7±0.9)° vs. (20.6±3.0)°) (t=21.148-45.355, P<0.01) and PI-LL ((5.2±2.8)° vs. (35.8±4.9)°, (17.9±2.9)° vs. (37.2±3.9)°, (25.8±2.7)° vs. (34.5±4.0)°) (t=7.227-38.250, P<0.01) were significantly reduced postoperative in PI-LL<10° group, 10°≤PI-LL≤20° group and PI-LL>20° group. Compared to preoperative, ODI (27.7±4.9 vs. 63.3±2.6, 17.7±5.9 vs. 63.1±2.8, 30.6±6.5 vs. 62.3±2.5) (t=21.218~50.858, P<0.01), JOA (2.8±1.2 vs. 5.2±1.2, 3.3±1.1 vs. 5.7±1.1, 2.8±1.7 vs. 5.7±1.2) (t=9.042-16.025, P<0.01) and VAS (2.9±1.2 vs.7.0±1.3, 3.3±0.9 vs.7.0±1.4, 2.9±0.8 vs. 6.3±1.2) (t=16.073-22.214, P<0.01) were all significantly reduced at last follow-up. There were statistic differences in ODI and LSDI (F=38.477, P<0.01; F=37.063, P<0.01) at the last follow-up among the three groups. There was a negative correlation in PI-LL and LSDI according to linear regression (B=-5.838, P<0.01) in the last follow-up. All the patients were followed up, the follow-up duration were 2 to 5 years with the mean (3.1±0.7) years. The internal fixation failure related complications in 3 years included proximal junctional kyphosis (PJK) in 19 cases, internal fixation loosening in 6 cases. Eight patients received reoperation for severe local pain and low extremity symptoms. PJK occurrences were significantly different among PI-LL<10° group, 10°≤PI-LL≤20° group and PI-LL>20° group. Conclusions The PI-LL between 10° and 20° may be the best choice in ADS patients after long posterior instrumentation and fusion for its better clinical outcome and less proximal junctional kyphosis (PJK). The overcorrection of LL may lead to more serious postoperative lumbar stiffness.