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Background Context: Cage subsidence after lumbar fusion can lead to many adverse outcomes. Low bone mineral density (BMD) is a widely recognized risk factor for cage subsidence. Conventional methods can predict and evaluate BMD, but there are many shortcomings. Recently, MRI-based assessment of bone quality in specific parts of the vertebral body has been proposed, including scores for vertebral bone quality (VBQ) and endplate bone quality (EBQ). However, the predictive accuracy of the two scoring systems for cage subsidence after transforaminal lumbar interbody fusion (TLIF) remains unknown. Therefore, we investigated MRI-based VBQ and EBQ scores for assessing bone quality and compared their predictive value for cage subsidence after TLIF., Purpose: To compare the predictive value between MRI-based VBQ and EBQ scores for cage subsidence after TLIF., Study Design/setting: A retrospective case-control study., Patients Sample: Patients with degenerative lumbar diseases underwent single-level TLIF at our medical center between 2014 and 2020, all of whom had preoperative MRIs available., Outcomes Measures: Cage subsidence, disc height, VBQ score, EBQ score, upper and lower vertebral body bone quality (UL-VBQ) score., Methods: Data were retrospectively examined for a consecutive sample of 346 patients who underwent TLIF at our medical center between 2014 and 2020. Patients who subsequently experienced cage subsidence or not were matched to each other based on propensity scoring, and the two matched groups (52 patients each) were compared using conditional logistic regression to investigate the association between the potential radiographic factors and cage subsidence. Scores for VBQ and EBQ were assessed for their ability to predict cage subsidence in the matched patients based on the area under the receiver operative characteristic curve (AUC)., Results: Among matched patients, those who suffered cage subsidence had significantly higher VBQ score (3.7 vs 3.1, p<.001) and EBQ score (5.0 vs 4.3, p<.001), and regression linked greater risk of subsidence to higher VBQ score (OR 4.557, 95% CI 1.076-19.291, p=.039) and higher EBQ score (OR 5.396, 95% CI 1.158-25.146, p=.032). A cut-off VBQ score of 3.4 predicted the cage subsidence among matched patients with an AUC of 0.799, sensitivity of 84.6%, and specificity of 69.2%. A cut-off EBQ score of 4.7 predicted subsidence with an AUC of 0.829, sensitivity of 76.9%, and specificity of 82.7%., Conclusion: Higher VBQ and EBQ scores are associated with a greater risk of cage subsidence following TLIF, and EBQ may perform better because of greater specificity., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Purpose: It is the first study to evaluate the predictive value of the geriatric nutritional risk index (GNRI) on postoperative delirium (POD) after transforaminal lumber interbody fusion (TLIF) in elderly patients with degenerative lumbar diseases., Methods: A retrospective study was conducted to assess the outcomes of TLIF surgery in elderly patients with lumbar degenerative disease between the years 2016 and 2022. Delirium was diagnosed by reviewing postoperative medical records during hospitalization, utilizing the Confusion Assessment Method. The geriatric nutritional risk index was calculated using the baseline serum albumin level and body weight. Multivariate logistic regression analysis was employed to identify the association between preoperative GNRI and postoperative delirium (POD). Additionally, a receiver operating characteristic curve was utilized to determine the optimal GNRI cutoff for predicting POD., Results: POD was observed in 50 of the 324 patients. The GNRI was visibly reduced in the delirium group. The mean GNRI was 93.0 ± 9.1 in non-delirium group and 101.2 ± 8.2 in delirium group. On multivariate logistic regression, Risk of POD increases significantly with low GNRI and was an independent factor in predicting POD following TLIF (OR 0.714; 95% CI 0.540-0.944; p = 0.018). On receiver operating characteristic curve, the area under curve (AUC) for GNRI was 0.738 (95% CI 0.660-0.817). The cutoff value for GNRI according to the Youden index was 96.370 (sensitivity: 66.0%, specificity: 70.4%)., Conclusion: Our study indicated that lower GNRI correlated significantly with POD after TLIF. Performing GNRI evaluation prior to TLIF may be an effective approach of predicting the risk for POD among elderly patients with degenerative lumbar diseases., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objectives: There is no consensus on the treatment of moderate-to-severe rigid scoliosis. Anterior release and three-column osteotomy are excessively traumatic, whereas posterior column osteotomy (PCO) alone results in poor outcomes. An emerging surgical technique, posterior intervertebral release (PR), can release the rigid spine from the posterior approach. This study was performed to compare the multi-segment apical convex PR combined with PCO and PCO alone in patients with moderate-to-severe rigid scoliosis., Methods: From June 2021 to June 2022, this prospective study of moderate-to-severe (Cobb: 70-90°) rigid scoliosis (flexibility of main curve <25%) involved two groups defined by surgical procedure: the PR group, the patients undergoing PR combined with PCO; and the PCO group, the patients undergoing PCO alone. Follow-up was at least 12 months. Radiographic results mainly included main curve Cobb, correction of per PR/PCO segment, apical vertebra rotation (AVR) and apical vertebra translation (AVT). Demographics, surgical data, complications were also recorded. Student's independent samples t test and Pearson's chi-square test were used to compare the differences between groups., Results: Forty patients with an average age of 16.65 years were included (PR group, n = 20; PCO group, n = 20). The main curves averaged 77.56° ± 5.86° versus 78.02° ± 5.72° preoperatively and 20.07° ± 6.73° versus 33.58° ± 5.76° (p < 0.001) at the last follow-up in the PR and PCO groups, respectively. The mean correction rates were 74.30% and 56.84%, respectively (p < 0.001). The average coronal curve correction was 13.49° per release segment, which was significantly higher than the PCO correction of 6.20° (p < 0.001). The correction of apical vertebra rotation and translation in the main thoracic curve was significantly better in the PR group than in the PCO group (p < 0.05). Several minor complications in the two groups improved after conservative treatment., Conclusion: The multi-segment apical convex PR combined with PCO offers more advantages than PCO alone in the treatment of patients with moderate-to-severe rigid scoliosis. Owing to its excellent corrective effect and few complications, this is a high benefit-risk ratio surgical strategy for rigid scoliosis., (© 2024 The Authors. Orthopaedic Surgery published by Tianjin Hospital and John Wiley & Sons Australia, Ltd.)

Objective: Recently, the MRI-based vertebral bone quality (VBQ) score has been shown to correlate with Hounsfeld units (HU) value, dual-energy X-ray absorptiometry (DEXA) T-score and predict osteoporotic fractures. Preoperative cervical HU value is an independent correlative factor for early titanium mesh cage (TMC) subsidence after anterior cervical corpectomy and fusion (ACCF). However, to date the direct association between cervical VBQ score and TMC subsidence has not been studied. This study aims to investigate the predictive effect of cervical VBQ score derived from sagittal non-contrast-enhanced T1-weighted MRI on the early TMC subsidence after ACCF., Methods: Patients who underwent one-level ACCF from January 2016 to January 2020 were included. We retrospectively collected baseline data on age, sex, body mass index (BMI), disease type, level of surgery and radiology parameters. The cervical VBQ score was measured using preoperative non-contrast-enhanced T1-weighted MRI. Univariate and multivariate logistic regression analysis were performed to screen the independent risk factors of TMC subsidence. The receiver operating characteristic (ROC) curve and area under curve (AUC) were performed to assess the predictive ability of TMC subsidence based on the cervical VBQ score. Spearman correlation analysis was used to determine the correlations between the cervical VBQ score and TMC subsidence., Results: A total of 134 patients who underwent one-level ACCF were included in this study, and 46 (34.33%) patients had TMC subsidence. Univariable analyses demonstrated that the age, TMC placement depth and VBQ score were associated with subsidence. The cervical VBQ score in the subsidence group was significantly higher than that in the no subsidence group (3.75 ± 0.45 vs. 3.20 ± 0.42, p < 0.001). The multivariate logistic regression analysis proved that the higher VBQ score (odds ratio[OR] = 13.563, 95% confidence interval [CI] 4.968 - 37.031, p < 0.001) was the only variable that significantly predicted subsidence. Using a VBQ score cutoff value of 3.445, the cervical VBQ score yielded a sensitivity of 69.6% and a specificity of 85.2% with an AUC of 0.810 to differentiate patients with subsidence and with no subsidence., Conclusion: Preoperative higher cervical VBQ score is an independent risk factor for TMC subsidence after ACCF. The cervical VBQ score may be a valuable tool for assisting in distinguishing the presence of TMC subsidence., (© 2023 The Authors. Orthopaedic Surgery published by Tianjin Hospital and John Wiley & Sons Australia, Ltd.)

Objective: This is the first study to evaluate the predictive value of the cervical vertebral bone quality (VBQ) score on zero-profile cage (ZPC)subsidence after anterior cervical discectomy and fusion (ACDF) using the Hounsfield units (HU) value of computed tomography as the reference., Methods: A total of 89 patients with at least 1 year of follow-up who underwent single-level ACDF with ZPC were retrospectively and consecutively included. VBQ and HU value were determined from preoperative T1-weighted magnetic resonance imaging and computed tomography. Subsidence was defined as ≥2 mm of migration of the cage into the superior or inferior endplate or both using lateral cervical spine radiography. The results were subjected to statistical analysis., Results: Subsidence was observed among 16 of the 89 study patients (Subsidence rate: 18.0%). The mean VBQ score was 2.94 ± 0.820 for patients with subsidence and 2.33 ± 0.814 for patients without subsidence. The multivariable analysis demonstrated that only an increased VBQ score (odds ratio: 1.823, 95% confidence interval : 0.918,3.620, P = 0.001) was associated with an increased rate of cage subsidence. There was a significant and moderate correlation between HU and VBQ (r = -0.507, P < 0.001). Using receiver operating characteristic curves, the area under the curve was 0.785, and the most appropriate threshold of VBQ was 2.68 (sensitivity 72.7%, specificity 82.1%)., Conclusions: The VBQ score may be a valuable tool for independently predicting ZPC subsidence after single-level ACDF., (Copyright © 2023. Published by Elsevier Inc.)

Background: Proximal junctional kyphosis (PJK) is a common complication following corrective surgery for adolescent idiopathic scoliosis (AIS) with a Lenke 5 curve. Previous studies have suggested that PJK may be associated with osteopenia, which is prevalent in AIS patients. MRI-based vertebral bone quality (VBQ) scores have been proposed as a valuable tool to assess preoperative bone quality. However, accurately measuring VBQ scores in Lenke 5 AIS patients with a structural lumbar curve can be challenging. Recently, a simplified S1 VBQ score has been proposed as an alternative method when the traditional VBQ score is not applicable. This study aims to evaluate the predictive value of the simplified S1 VBQ score in predicting the occurrence of PJK after corrective surgery for Lenke 5 AIS., Methods: We conducted a retrospective analysis of patient data to assess the predictive utility of the S1 VBQ score for PJK in Lenke 5 AIS patients. Demographic, radiographic, and surgical data were collected, and S1 VBQ scores were calculated based on preoperative T1-weighted MRI images. Univariate analysis, linear regression, and multivariate logistic regression were performed to identify potential risk factors for PJK and to assess the correlation between other variables and the S1 VBQ score. Receiver operating characteristic analysis and area under the curve values were used to evaluate the predictive efficiency of the S1 VBQ score for PJK., Results: A total of 105 patients (aged 15.50 ± 2.36 years) were included in the analysis, of whom 24 (22.9%) developed PJK. S1 VBQ scores were significantly higher in the PJK group compared to the non-PJK group (2.83 ± 0.44 vs. 2.48 ± 0.30, P < 0.001), and there was a significant positive correlation between the S1 VBQ score and proximal junctional angle (PJA) (r = 0.46, P < 0.0001). Multivariate analysis revealed that the S1 VBQ scores and preoperative thoracic kyphosis (TK) were significant predictors of PJK., Conclusion: This study provided evidence that higher S1 VBQ scores were independently associated with PJK occurrence following corrective surgery for Lenke 5 AIS. Preoperative measurement of the S1 VBQ score on MRI may serve as a valuable tool in planning surgical correction for Lenke 5 AIS., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objective: Previous studies have confirmed that the nanohydroxyapatite/polyamide-66 (n-HA/PA66) cage is an ideal alternative material for degenerative lumbar disease (DLD) comparable to the polyether ether ketone (PEEK) cage due to its similar radiographic fusion, subsidence rate, and clinical results. However, these studies were restricted to one-level surgery. The aim of this study was to analyze the long-term clinical and radiologic outcomes between n-HA PA66 cage and PEEK cage for patients with multi-level degenerative lumbar diseases (DLDs)., Methods: We retrospectively reviewed all patients who underwent multi-level transforaminal lumbar interbody fusion (TLIF) from June 2010 to December 2016 with a minimum 6-year follow-up. Matched-pair analysis was performed using a 1-to-1 closest neighbor approach to match patients who received an n-HA PA66 cage with those who received a PEEK cage. Clinical outcomes and radiographic evaluations were compared between the two groups. The independent student's t-test and χ 2 -test were applied to compare the differences between groups., Results: At the end of the propensity score matching (PSM) analysis, 48 patients from n-HA/PA66 group were matched to 48 patients in the PEEK group. No significant difference was observed in cage subsidence and bony fusion except for adjacent segment degeneration (ASD). The occurrence of ASD was 14.58% (7/48) in the n-HA/PA 66 group, which was significantly less than that in the PEEK group (33.33% [16/48]) (p = 0.031). Although the intervertebral space height (IH), segmental angle (SA) and lumbar lordosis (LL) significantly increased after surgery in both groups, there was no significant difference at any time point after surgery (p > 0.05). The visual analogue scale (VAS) and Oswestry disability index (ODI) scores significantly improved in both groups at 3m postoperative, 1y postoperative and at final follow-up. However, there were no significant differences in the VAS and ODI score at any time point (p > 0.05). The total complications and re-admission rate were not different between the two groups., Conclusion: Overall, our data suggest that the outcomes of n-HA/PA66 cage group are comparable to those of the PEEK cage group, with a similar high fusion rate and low cage subsidence rate as PEEK cages, except its lower rate of ASD occurrence., (© 2023 The Authors. Orthopaedic Surgery published by Tianjin Hospital and John Wiley & Sons Australia, Ltd.)

Objectives: The treatment of scoliosis with a severe rib hump remains a major challenge. Traditional vertebral rotation techniques are not satisfactory, and thoracoplasty has many pulmonary complications that limit its application. A novel surgical device, the multiple screw distraction reducer (MSDR) system, provides longitudinal distraction during the corrective operation while at the same time providing lateral translation and axial derotation, which may facilitate the correction of a rib hump. This study was performed to investigate the effectiveness of the MSDR system for adolescent idiopathic scoliosis (AIS) with a severe rib hump., Methods: This was a case-matched study of patients with retrospectively collected data from our hospital between January 2017 and December 2021. Sixty-eight patients who underwent one-stage posterior pedicle screw-instrumented spinal fusion were matched by the Cobb angle of the main curve and rib hump. All patients underwent a minimum of 2 years of follow-up. The patients were divided into two groups: the MSDR group (using the MSDR system, n = 34) and the DVR group (using direct vertebral derotation, n = 34). The patients were evaluated for the height of the rib hump, deformity correction, complications, and SRS-30 scores. The unpaired Student's t-test and Pearson's χ 2 -test were used to compare the outcome measures between the two groups. Multiple linear regression analysis was used to examine the variables that affected the correction of a rib hump., Results: The rib hump was 30.21 ± 6.21 mm versus 29.35 ± 6.52 mm (p = 0.583) preoperatively and 9.18 ± 4.06 mm versus 13.82 ± 5.54 mm (p < 0.001) at the last follow-up in the MSDR and DVR groups, respectively. The correction rates were 70.83% and 53.56%, respectively (p < 0.001). Preoperatively, the main thoracic curve was 58.43° ± 7.97° and 57.84° ± 6.32° (p = 0.736) and was corrected to 10.92° ± 5.47° and 19.14° ± 5.32° (p < 0.001) at last follow-up in the MSDR and DVR group, respectively. Thoracic kyphosis was restored from 18.24° ± 5.19° and 17.98° ± 5.28° (p = 0.836) in the MSDR and DVR group to 24.59° ± 4.41° and 19.32° ± 4.96° (p < 0.001), respectively. Correction of apical vertebra rotation and translation in the main thoracic curve were significantly better in the MSDR group than in the DVR group (p < 0.05). There was no significant difference in the Lenke type, implant density, estimated blood loss, or follow-up duration between the two groups, whereas the operation time in the DVR group was significantly less than that in the MSDR group. There were only two minor pulmonary complications in the MSDR group. At the last follow-up, the MSDR group scored higher in terms of appearance and satisfaction (p < 0.05)., Conclusion: The MSDR system, enabling better coronal alignment, thoracic kyphosis, and axial derotation, could be a safe and effective technique for severe rib hump correction in AIS., (© 2023 The Authors. Orthopaedic Surgery published by Tianjin Hospital and John Wiley & Sons Australia, Ltd.)

Objective: Previous studies have found satisfactory clinical results with the nano-hydroxyapatite/polyamide 66 (n-HA/PA66) cage to reconstruct the stability of anterior cervical column. However, studies evaluating the long-term outcomes of the n-HA/PA66 cage in multi-level degenerative cervical myelopathy (MDCM) have not been reported. This study aims to compare the outcomes of corpectomy anterior cervical discectomy and fusion (ACDF) hybrid procedures between the n-HA/PA66 cage and titanium mesh cage (TMC) to treat MDCM., Methods: After the screening for eligibility, this retrospective study involved 90 patients who underwent corpectomy ACDF hybrid (CACDFH) procedure from June 2013 to June 2018. The CACDFH procedure is the combination of ACDF and anterior cervical corpectomy and fusion (ACCF). According to the cage utilized, we categorized patients into a n-HA/PA66 cage group and a TMC group. Then, stepwise propensity score matching (PSM) was performed to maintain comparable clinical data between groups. All the patients were followed up ≥4 years and the longest follow-up time was 65.43 (±11.49) months. Cage subsidence, adjacent segment degeneration (ASD), segmental height (SH), segmental angle (SA), cervical lordosis (CL), and clinical data (visual analogue scale [VAS] and Japanese Orthopaedic Association [JOA] score) was evaluated preoperatively, at 1 week, and at the final surgery follow-up. The independent student's t test and chi-square test were applied to compare the differences between groups., Results: Through PSM analysis, 25 patients from the n-HA/PA66 group were matched to 25 patients in the TMC group. The occurrence of ASD was 16.0% (4/25) in the n-HA/PA 66 group, which was significantly less than in the TMC group at 44.0% (11/25) (p = 0.031). Moreover, the cage subsidence rate was significantly higher in the TMC group as compared to the n-HA/PA 66 group (40.0% vs. 12.0%, p = 0.024). But there was no significant difference in SH, SA, and CL at any time after surgery as determined through follow-up. The VAS and JOA scores significantly improved in both groups at 3 months postoperative and at final follow-up. However, there were no significant differences in the VAS and JOA score at any time between the two groups in preoperative (p > 0.05)., Conclusion: The n-HA/PA66 cage is associated with lower rate of cage subsidence and ASD than the TMC in the treatment of MDCM. The n-HA/PA66 cage could be superior to the TMC in corpectomy ACDF hybrid procedures., (© 2023 The Authors. Orthopaedic Surgery published by Tianjin Hospital and John Wiley & Sons Australia, Ltd.)

Introduction: Proximal junctional kyphosis (PJK) is one of the most common complications after thoracic AIS surgery. Previous studies reported that the etiology of PJK was associated with osteopenia and meanwhile the AIS patients were found osteopenia which could persist into adulthood. Recently, an MRI-based vertebral bone quality score (VBQ) was reported to be a promising tool which can assess preoperative bone quality., Objective: This study aims to evaluate the utility of VBQ score in predicting PJK after corrective surgery for thoracic AIS (Lenke 1 and 2)., Methods: We conducted a retrospective study to identify the predictive efficiency of VBQ score for PJK in thoracic AIS patients. Demographic, radiographic parameters, and surgical variables were collected. VBQ score was calculated using preoperative T1-weighted MRI. Univariate analysis, linear regression, and multivariate logistic regression were performed to determine potential risk factors of PJK and correlation between other parameters and VBQ score. Receiver operating characteristic analysis and area under the curve values were utilized to evaluate the predictive efficiency of VBQ score for PJK., Results: A total of 206 patients (aged 14.4 ± 2.3 years) were included, of which 33 (16.0%) developed PJK. VBQ scores were significantly different between the PJK and non-PJK groups (2.8 ± 0.2 vs 2.5 ± 0.2, P < 0.01). A significant positive correlation was found between VBQ score and PJA (R 2  = 0.1728, P < 0.01).On multivariate analysis, VBQ score was the only significant predictor of PJK (odds ratio = 2.178, 95% CI = 1.644-2.885, P < 0.001), with a predictive accuracy of 83%., Conclusion: Higher VBQ scores were independently associated with PJK occurrence after corrective surgery for thoracic AIS. Preoperative measurement of VBQ score on MRI may serve as a valuable tool in planning thoracic AIS surgery., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objective: Although direct isthmic repair, such as PSVPH, did not affect the mobility of the fixed segment and adjacent segment, it has a relatively low rate of isthmic fusion compared with conventional fusion. The Isobar TTL dynamic internal fixation system has been widely used in clinical practice and has achieved satisfactory clinical results. However, the use of the Isobar TTL system in combination with direct isthmic repair for lumbar spondylolysis has rarely been reported. The aim of this study was to compare the clinical and radiologic outcomes between patients who underwent Isobar TTL system and PSVPH with direct repair of defect for lumbar spondylolysis., Methods: Stepwise propensity score matching (PSM) for age and sex were performed to keep comparable clinical data between groups in this retrospective and matched-pair case control study. A total of 50 patients diagnosed with lumbar spondylolysis underwent surgical implantation of the Isobar TTL group (n = 25) or PSVPH group (n = 25) from June 2009 to June 2016. Clinical outcomes were assessed using the Oswestry disability index (ODI), and visual analog score (VAS). Radiographic evaluations included range of motion (ROM) and the disc heights of stabilized segment and adjacent segment, adjacent segment degeneration (ASD) and bony fusion. Three-dimensional reconstruction of lumbar CT scan was obtained to evaluate bone fusion of the isthmic at final follow-up. The independent Student's t test and chi-square test were applied to compare the differences between groups., Results: A total of 25 patients from TTL group were matched to 25 patients in PSVPH group for age, sex, body mass index (BMI), defect side, spondylolisthesis meyerding, and follow-up duration. The intervertebral space height (IH) of stabilized segment at postoperative 1 week and final follow-up in the TTL group was higher than those in the PSVPH group, respectively (P = 0.030; P = 0.013). The ROM of stabilized segment at final follow-up in the TTL group was significantly lower than that in the PSVPH group (P < 0.001). The bony fusion rate at the final follow-up was 88.0% (22/25 cages) in the TTL group and 80.0% (20/25 cages) in the PSVPH group. The ODI score at final follow-up in the TTL group was significantly lower than that in the PSVPH group (P = 0.007)., Conclusion: Overall, our data suggest that the Isobar TTL system outcomes are comparable to those in the PSVPH, with a similar high bony fusion rate as PSVPH, especially its wider indications as a new surgery., (© 2023 The Authors. Orthopaedic Surgery published by Tianjin Hospital and John Wiley & Sons Australia, Ltd.)

Objective: At present, the influence of Modic changes (MCs) on postoperative fusion rate of lumbar interbody fusion (LIF) is mainly focused on the medium- and long-term fusion rate, while the short-term fusion rate has not been reported. The aim of this study was to compare the short-term fusion rate of lumbar degenerative disease patients with and without MCs after single level transforaminal lumbar interbody fusion (TLIF)., Methods: In this retrospective and matched-pair case control study, we included 100 patients who underwent TLIF from January 2017 to January 2020 and had at least two follow-up visits over a two-year period. Fifty patients with MCs (MCs group) were matched with 50 patients without MCs (non MCs group) for age, sex, surgical level, diagnosis, operative time, and intraoperative blood loss. We collected the X-ray and computed tomography (CT) data of patients from 3 months to 2 years after the operation to assess bony fusion and the cage union ratio. According to the type of cage, the MCs group was further divided into the nano-hydroxyapatite/polyamide 66 (n-HA/PA66) group and polyetheretherketone (PEEK) group, and the fusion performance between the two groups was compared. Finally, age, sex, body mass index (BMI), smoking and cage type were included in the logistic regression model for risk factor analysis., Results: The bony fusion rates in the MCs group at 3 months, 6 months, 1 year and 2 years after surgery were significantly lower than those in the non MCs group (P < 0.05) (23.8% vs 62.5%, 52.6% vs 78.9%, 61.1% vs 83.3%, 74.0% vs 90.0%). The average coronal cage union ratios of the upper and lower endplates in the MCs group were significantly lower than those in the non MCs group (54.3% ± 17.5% vs 75.0% ± 17.2%, P < 0.05; 73.3% ± 12.0% vs 84.9% ± 8.0%, P < 0.05). Similarly, analogous results were obtained by comparing the MCs and non MCs groups' three-dimensional CT sagittal plane images (62.5% ± 16.5% vs 76.1% ± 12.4%, P < 0.05; 67.0% ± 13.9% vs 79.8% ± 11.5%, P < 0.05)., Conclusion: Short-term fusion rates were lower in the MCs group than in the non MCs group. The coronal and sagittal cage union ratio in the MCs group was lower than that in the non MCs group. The fusion performance of n-HA/PA66 and PEEK cages in the MCs group was comparable., (© 2023 The Authors. Orthopaedic Surgery published by Tianjin Hospital and John Wiley & Sons Australia, Ltd.)

Purpose: This is the first study to evaluate the predictive value of the vertebral bone quality (VBQ) score on cage subsidence after transforaminal lumbar interbody fusion (TLIF) in a Chinese population using the spinal quantitative computed tomography (QCT) as the clinical standard. Meanwhile, the accuracy of the MRI-based VBQ score in bone mineral density (BMD) measurement was verified., Methods: We performed a retrospective study of patients who underwent single-level TLIF from 2015 to 2020 with at least 1 year of follow-up. Cage subsidence was measured using postoperative radiographic images based on cage protrusion through the endplates more than 2 mm. The VBQ score was measured on T1-weighted MRI. The results were subjected to statistical analysis., Results: A total of 283 patients (61.1% of female) were included in the study. The subsidence rate was with 14.1% (n = 40), and the average cage subsidence was 2.3 mm. There was a significant difference in age, sex, VBQ score and spinal QCT between the subsidence group and the no-subsidence group. The multivariable analysis demonstrated that only an increased VBQ score (OR = 2.690, 95% CI 1.312-5.515, p = 0.007) and decreased L1/2 QCT-vBMD (OR = 0.955, 95% CI 0.933-0.977, p < 0.001) were associated with an increased rate of cage subsidence. The VBQ score was found to be moderately correlated with the spinal QCT (r = -0.426, p < 0.001). The VBQ score was shown to significantly predict cage subsidence, with an accuracy of 82.5%., Conclusion: Our findings indicate that the MRI-based VBQ score is a significant predictor of cage subsidence and could be used to assess BMD., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: The nano-hydroxyapatite/polyamide-66 (n-HA/PA66) cage is a biomimetic cage with a lower elastic modulus than the titanium mesh cage (TMC). This study aimed to compare the long-term outcomes of the n-HA/PA66 cage and TMC in the anterior reconstruction of thoracic and lumbar fractures., Methods: We retrospectively studied 113 patients with acute traumatic thoracic or lumbar burst fractures, comprising 60 patients treated with the TMC and 53 treated with the n-HA/PA66 cage for anterior reconstruction following single-level corpectomy. The radiographic data (cage subsidence, fusion status, segmental sagittal alignment) and clinical data (visual analogue scale (VAS) for pain and Oswestry Disability Index (ODI) for function) were evaluated preoperatively, postoperatively, and at final follow-up after a minimum 7-year period., Results: The n-HA/PA66 and TMC groups had similar final fusion rates (96.2% vs. 95.0%). The cage subsidence at final follow-up was 2.3 ± 1.6 mm with subsidence of more than 3 mm occurring in 24.5% in the n-HA/PA66 group, which was significantly lower than the respective values of 3.9 ± 2.5 mm and 58.3% in the TMC group. The n-HA/PA66 group also had better correction of the bisegmental kyphotic angle than the TMC group (7.1° ± 7.5° vs 1.9° ± 8.6°, p < 0.01), with lower loss of correction (2.9° ± 2.5° vs 5.2° ± 4.1°, p < 0.01). The mean ODI steadily decreased after surgery in both groups. At final follow-up, the ODI and VAS were similar in the TMC and n-HA/PA66 groups., Conclusions: The n-HA/PA66 cage is associated with excellent radiographic fusion, better maintenance of the height of the fused segment, and better correction of kyphosis than the TMC during 7 years of follow-up after one-level anterior corpectomy. With the added benefit of radiolucency, the n-HA/PA66 cage may be superior to the TMC in anterior reconstruction of thoracic or lumbar fractures., (© 2023. The Author(s).)

Objective: Multiple hemivertebrae (MHV) is defined as three or more hemivertebrae, and is relatively uncommon among patients with congenital scoliosis. This study aimed to compare the natural history of different kinds of MHV and describe the surgical outcome of MHV., Methods: In this retrospective cohort study, a total of 50 patients diagnosed with MHV were enrolled from June 2007 to June 2018. The medical records and radiographs of these patients were reviewed to summarize the characteristics of MHV. Patients with MHV were divided into the unbalanced (UB) group, partially unbalanced (PUB) group, and completely balanced (CB) group. Medical records and radiographs of MHV patients were reviewed to collect HV position, natural history, coronal and sagittal parameters. A Mann-Whitney U test was used to compare the radiographical data, such as the cobb angle of main curve and secondary curve, and Fisher's exact test was used to compare the patients in different kinds of MHV with surgical indication or not., Results: The average number of hemivertebrae was 3.6 and the average main curve was 57.5°. Twenty-four of 50 patients had associated anomalies, including four patients with sacral agenesis, one with tetralogy of Fallot, two with congenital imperforate anus, and 17 with Klippel-Feil syndrome. In 22 patients who underwent MRI imaging, three patients had mild syringomyelia and three patients had diastematomyelia. The UB and PUB groups had a larger main curve and compensatory curve than the CB group. Of the 25 patients with follow-up before surgery, the curve progression rate was highest in the UB group (12.1°/year) but similar in the PUB group (4.2°/year) and CB group (3.6°/year). All patients in the UB and PUB group met the criteria for surgery. In contrast, only 10 of 23 patients in the CB group had surgical indications. Eighteen of the 37 patients with surgical indications chose to undergo surgery and the correction rate of the main curve was 51.4%., Conclusions: Early surgical intervention should be considered for most patients with UB or PUB MHV. For patients with CB MHV, surgical treatment may not be urgently needed at the first visit. Posterior hemivertebrectomy could be used for the treatment of MHV with satisfying radiographic outcome., (© 2023 The Authors. Orthopaedic Surgery published by Tianjin Hospital and John Wiley & Sons Australia, Ltd.)

Background: Current evidence suggests that the magnetic resonance imaging (MRI)-based vertebral bone quality (VBQ) score is a good parameter for evaluating bone quality. We aimed to assess whether the VBQ score can predict the occurrence of postoperative cage subsidence after oblique lumbar interbody fusion (OLIF) surgery., Methods: Patients (n = 102) who had undergone single-level OLIF with a minimal follow-up for 1 year were reviewed in this study. Demographic and radiographic data of these patients were collected. Cage subsidence was defined as ≥ 2 mm of cage migration into the inferior endplate, superior endplate, or both. Further, the MRI-based VBQ score was measured on T1-weighted images. Moreover, univariable and multivariable binary logistic regression analyses were performed. Meanwhile, Pearson analysis was used to evaluate the correlation among the VBQ score, average lumbar dual-energy X-ray absorptiometry (DEXA) T-score, and degree of cage subsidence. Furthermore, ad-hoc analysis was used along with receiver operating characteristic curve analysis to assess the predictive ability of the VBQ score and average lumbar DEXA T-score., Results: Of 102 participants, cage subsidence was observed in 39 (38.24%) patients. According to the univariable analysis, patients with subsidence had older age, higher antiosteoporotic drug use, larger disk height change, a more concave morphology of inferior and superior endplates, higher VBQ score, and lower average lumbar DEXA T-score compared to patients without subsidence. In the multivariable logistic regression analysis, a higher VBQ score was significantly associated with an increased risk of subsidence (OR = 23.158 ± 0.849, 95% CI 4.381-122.399, p < 0.001), and it was the only significant and independent predictor of subsidence after OLIF. Moreover, the VBQ score was moderately correlated with the average lumbar DEXA T-score (r = - 0.576, p < 0.001) and the amount of cage subsidence (r = 0.649, p < 0.001). Furthermore, this score significantly predicted cage subsidence with an accuracy of 83.9%., Conclusions: The VBQ score can independently predict postoperative cage subsidence in patients undergoing OLIF surgery., (© 2023. The Author(s).)

Background: A novel nanohydroxyapatite/polyamide-66 cage (n-HA/PA66 cage) with a horseshoe shape was designed to lower the subsidence rate of the traditional hollow cylindrical n-HA/PA66 cage. However, no studies have compared the incidence of subsidence in the two cages. The purpose of this study was to compare the long-term clinical and radiological outcomes of the novel n-HA/PA66 cage with the hollow cylindrical n-HA/PA66 cage after anterior cervical discectomy and fusion (ACDF) to treat single-level cervical degenerative disk disease (CDDD)., Methods: Fifty-two patients with novel n-HA/PA66 cages (Group A) and fifty-five patients with hollow cylindrical n-HA/PA66 cages (Group B) were included. The radiological parameters included intervertebral height (IH), C2-7 angle (C2-7a), segmental alignment (SA), subsidence rate, and fusion rate. The clinical outcomes were visual analog scale (VAS) scores, Japanese Orthopedic Association (JOA) scores, and patient satisfaction rates., Results: The pre- and postoperative SA, C2-7a, and fusion rates of the patients in Groups A and B were similar. The preoperative and 6-month postoperative IHs in both groups were comparable. However, the final follow-up IH in Group B was significantly smaller than that in Group A (35.9 mm vs. 36.7 mm). The difference in the subsidence rates at the final follow-up between Group A (5.8%, 3/52) and Group B (18.2%, 10/55) was significant. The VAS score, JOA score, and patient satisfaction rate were not significantly different., Conclusions: The novel n-HA/PA66 cage had similar favorable SA, C2-7a, fusion rate, and clinical outcomes compared to the hollow cylindrical n-HA/PA66 cage for treating single-level ACDF. Moreover, the novel n-HA/PA66 cage achieved a lower subsidence rate and higher IH than the hollow cylindrical n-HA/PA66 cage at the final follow-up., (© 2023. The Author(s).)

Background: In clinical practice, there are a significant percentage of Lenke 2 AIS patients suffered from medial shoulder imbalance (MSI) despite achieving good lateral shoulder balance (LSB) following surgery. However, there are few studies evaluating the features of the medial shoulder. The objective of this study was to determine the incidence and independent risk factors of MSI with LSB after Lenke 2 AIS corrective surgery., Methods: One hundred and twenty Lenke 2 AIS patients with LSB at the last follow-up were reviewed from 2009 to 2018. Preoperative, and 3-month and the last postoperative follow-up radiographs were measured using a number of specific measurements. At the last follow-up, patients were divided into medial shoulder balance (MSB) group and the MSI group according to whether the T1 tilt was greater than 3°. A stepwise multiple linear regression analysis was used to examine the independent risk factors for MSI. Scoliosis Research Society (SRS)-30 questionnaire was used to assess clinical outcomes., Results: Up to 69.2% of patients suffered from MSI with LSB after Lenke Type 2 AIS corrective surgery. Multiple regression showed that postoperative upper instrumented vertebra tilt (UIVt), proximal thoracic curve (PTC), the ratio of PTC and main thoracic curves (PTC/MTC) and T2 vertebra rotation ratio (T2-VR) were significant predictors for MSI (UIVt: b = 0.398, p < 0.001; PTC/MTC: b = 2.085, p < 0.001; PTC: b = 0.155, p < 0.001; T2-VR: b = 3.536, p = 0.008; adjusted R 2  = 0.711). 72 patients completed the SRS-30 questionnaire survey, and the MSB group were scored the higher (p ≤ 0.001) in self-image domain (4.18 ± 0.43 vs. 3.70 ± 0.35), satisfaction domain (4.39 ± 0.54 vs. 3.95 ± 0.46) and total average (4.31 ± 0.23 vs. 4.11 ± 0.19)., Conclusion: Although the patients with Lenke 2 AIS achieve LSB after corrective surgery, up to 69.2% of them suffered from MSI. Postoperative UIVt, PTC, PTC/MTC and T2-VR were significant predictors for MSI. Sufficient correction of these variables may facilitate the achievement of MSB., (© 2022. The Author(s).)

Background: Proximal junctional kyphosis is a common complication after posterior fusion in patients with adolescent idiopathic scoliosis and is correlated with postoperative changes of thoracic kyphosis. In lenke 5c patients, higher postoperative LL and spontaneous change of TK may produce an effect on final PJK. However, no studies has been performed to evaluate the correlation of PJK with thoracocervical parameters in patients with AIS., Methods: Data from 98 patients who underwent posterior fusion for Lenke 5C AIS with 2 years of follow-up were retrospectively reviewed. Patients in the extended fusion group underwent fusion at levels higher than upper-end vertebra + 2 (n = 38), and those in the thoracolumbar/lumbar (TL/L) fusion group underwent fusion at UEV + 2 or lower (n = 60)., Results: During an average follow-up of 38.1 months, 23 of 98 patients developed PJK. The extended fusion group had a higher incidence of PJK than the TL/L fusion group (14/38 vs. 9/60, respectively; P = 0.01) and a significantly greater decrease in thoracic kyphosis than the TL/L group (P < 0.01). Patients with PJK had a significantly larger preoperative thoracic inlet angle (TIA) than those without PJK (P < 0.01). Multivariate analysis showed that a greater preoperative TIA and extended fusion were associated with PJK. The Scoliosis Research Society 22-item questionnaire score did not significantly differ between the PJK and non-PJK groups., Conclusions: The preoperative TIA could be a predictor of PJK. Among patients with Lenke 5C AIS, those with a TIA of > 71° are more likely to develop PJK. Additionally, extended fusion in patients with Lenke 5C may increase the risk of PJK., (© 2022. The Author(s).)

Objective: To introduce a new occipitocervical angle parameter, occipito-odontoid angle (O-Da), for predicting dysphagia after occipitocervical fusion (OCF) in patients with C 2, 3 Klippel-Feil syndrome (KFS) and analyze its effectiveness., Methods: A total of 119 patients met selective criteria between April 2010 and November 2019 were retrospectively included as the study subjects. There were 56 males and 63 females. The age ranged from 14 to 76 years, with a median age of 51 years. There were 44 cases of basilar invagination and 75 cases of atlantoaxial subluxation. Forty patients were combined with C 2, 3 KFS. Seven patients underwent anterior decompression combined with posterior OCF and 112 patients underwent posterior OCF. The fixed segments were O-C 2 in 36 cases, O-C 3 in 51 cases, O-C 4 in 25 cases, and O-C 5 in 7 cases. All patients were followed up 21-136 months, with a median time of 79 months. The lateral cervical X-ray films before operation and at last follow-up were used to measure the occipital to C 2 angle (O-C 2 a), the occipital and external acoustic meatus to axis angle (O-EAa), the occipital protuberance to axial angle (Oc-Axa), the O-Da, and the narrowest oropharyngeal airway space (nPAS). The differences of the above parameters between the last follow-up and the preoperative values were calculated (represented as dO-C 2 a, dO-EAa, dOc-Axa, dO-Da, and dnPAS). Patients were divided into two groups according to whether they suffered dysphagia after operation, and the differences in clinical data and radiographic parameters were compared between the two groups. The correlation between occipitocervical angle parameters and nPAS in 40 patients with C 2, 3 KFS was analyzed respectively. In addition, sensitivity and specificity analyses were used to assess the effectiveness of dO-Da≤-5° for the prediction of postoperative dysphagia., Results: Thirty-one patients (26.1%) suffered dysphagia after OCF (dysphagia group), including 10 patients with C 2, 3 KFS; no dysphagia occurred in 88 patients (non-dysphagia group). There was no significant difference in age, follow-up time, fixed segment, proportion of patients with rheumatoid arthritis, proportion of patients with atlantoaxial subluxation, and proportion of patients with C 2, 3 KFS between the two groups ( P >0.05). The proportion of female patients was significantly higher in dysphagia group than in non-dysphagia group ( χ 2 =7.600, P =0.006). The difference in preoperative O-C 2 a between the two groups was significant ( t =2.528, P =0.014). No significant differences were observed in preoperative O-EAa, Oc-Axa, O-Da, and nPAS ( P >0.05). There was no significant difference in dO-C 2 a, dO-EAa, dOc-Axa, dO-Da, and dnPAS between the two groups ( P >0.05). The dO-C 2 a, dO-EAa, dOc-Axa, and dO-Da were positively correlated with dnPAS in 40 patients with C 2, 3 KFS ( r =0.604, P <0.001; r =0.649, P <0.001; r =0.615, P <0.001; r =0.672, P <0.001). Taking dO-Da≤-5° as the standard, the sensitivity and specificity of dO-Da to predict postoperative dysphagia in patients with C 2, 3 KFS were 80.0% (8/10) and 93.3% (28/30), respectively., Conclusion: The dO-Da is a reliable indicator for predicting dysphagia after OCF in patients with C 2, 3 KFS.

Background: Improper occipitocervical alignment after occipitocervical fusion (OCF) may lead to devastating complications, such as dysphagia and/or dyspnea. The occipital to C2 angle (O-C2a), occipital and external acoustic meatus to axis angle (O-EAa) have been used to evaluate occipitospinal alignment. However, it may be difficult to identify the inferior endplate of the C2 vertebra in patients with C2-3 Klippel-Feil syndrome (KFS). The purpose of this study aimed to compare four different parameters for predicting dysphagia after OCF in patients with C2-3 KFS., Methods: There were 40 patients with C2-3 KFS undergoing OCF between 2010 and 2019. Radiographs of these patients were collected to measure the occipital to C3 angle (O-C3a), O-C2a, occipito-odontoid angle (O-Da), occipital to axial angle (Oc-Axa), and narrowest oropharyngeal airway space (nPAS). The presence of dysphagia was defined as the patient complaining of difficulty or excess endeavor to swallow. Patients were divided into two groups according to whether they had postoperative dysphagia. We evaluated the relationship between each of the angle parameters and nPAS and analyzed their influence to the postoperative dysphagia., Results: The incidence of dysphagia after OCF was 25% in patients with C2-3 KFS. The Oc-Axa, and nPAS were smaller in the dysphagia group compared to non-dysphagia group at the final follow-up (p < 0.05). Receiver-operating characteristic (ROC) curves showed that dO-C3a had the highest accuracy as a predictor of the dysphagia with an area under the curve (AUC) of 0.868. The differences in O-C3a, O-C2a, O-Da, and Oc-Axa were all linearly correlated with nPAS scores preoperatively and at the final follow-up within C2-3 KFS patients, while there was a higher R 2 value between the dO-C3a and dnPAS. Multiple linear regression analysis showed that the difference of O-C3a was the only significant predictor for dnPAS (β = 0.670, p < 0.001)., Conclusions: The change of O-C3a (dO-C3a) is the most reliable indicator for evaluating occipitocervical alignment and predicting postoperative dysphagia in C2-3 KFS patients. Moreover, dO-C3a should be more than - 2° during OCF to reduce the occurrence of postoperative dysphagia., (© 2022. The Author(s).)

Background: Numerous studies on the comparison of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and open-transforaminal lumbar interbody fusion (O-TLIF) for the treatment of lumbar disc herniation (LDH) have been published, but there is no clear conclusion., Objective: The aim of this study was to evaluate the efficacy of MIS-TLIF compared with O-TLIF in the treatment of LDH in the Chinese population by meta-analysis., Methods: Studies on the treatment of LDH by MIS-TLIF versus O-TLIF were searched in Pubmed, Web of Science, Medline, Embase, CNKI, VIP and China Wanfang databases from the establishment of the databases to January 2020. The meta-analysis was used to analyze the pooled operation time, intraoperative blood loss, postoperative drainage, postoperative ground movement time, Waist and leg Visual Analogue Scale (VAS) score, Oswestry Disability Index (ODI) score and Japanese orthopaedic association (JOA) score. Mean difference (MD) and standard mean difference (SMD) were used as the effect size., Results: Eleven studies with 1132 patients were included. The results showed that MIS-TLIF compared with O-TLIF, MD =-133.82 (95% CI: -167.10 ∼-100.53, P< 0.05) in intraoperative blood loss, MD =-114.43 (95% CI: -141.12 ∼-87.84, P< 0.05) in postoperative drainage, MD =-3.30 (95% CI: -4.31 ∼-2.28, P< 0.05) in postoperative ground movement time, SMD =-1.44 (95% CI: -2.63 ∼-0.34, P< 0.05) in postoperative low back pain VAS score, SMD = 0.41 (95% CI: 0.15 ∼ 0.66, P< 0.05) in postoperative JOA score, MD = 4.12 (95% CI: -11.64 ∼ 19.87, P> 0.05) in the average operation time, SMD =-0.00 (95% CI: -0.36 ∼ 0.36, P> 0.05) in leg pain VAS score, and SMD =-0.59 (95% CI: -1.22 ∼ 0.03, P> 0.05) in ODI score., Conclusion: MIS-TLIF was superior to O-TLIF in the treatment of LDH, especially in the intraoperative blood loss, postoperative drainage, postoperative ground movement time and low back pain in the Chinese population.

Purpose: This study aimed to quantify osteotomy protocol for severe spinal deformity correction based on pre-operative demographic, clinical and radiologic parameters., Methods: A total of 131 Yang's A type severe spinal deformity patients were included. All patients received one of following osteotomies: Ponte/2 (Ponte osteotomy/Grade 2 osteotomy, n = 30), PSO/3 (pedicle subtraction osteotomy/Grade 3 osteotomy, n = 19), BDBO/4 (bone-disc-bone osteotomy/Grade 4 osteotomy, n = 26), SVCR/5 (single-level vertebral column resection/Grade 5 osteotomy, n = 38) and MVCR/6 (multilevel vertebral column resection/Grade 6 osteotomy, n = 18). Demographic, clinical and radiologic characteristics were compared among groups., Results: Tukey's test identified 6 significant variables between paired groups: age for MVCR/6 versus Ponte/2 + PSO/3 + BDBO/4 + SVCR/5 groups; bending Cobb angle for Ponte/2 versus MVCR/6; sagittal deformity angular ratio (S-DAR) for Ponte/2 + PSO/3 versus BDBO/3 + SVCR/5 versus MVCR/6; pre-operative scoliosis for Ponte/2 versus SVCR/5; total-DAR (T-DAR) and pre-operative kyphosis for Ponte/2 + PSO/3 versus BDBO/4 + SVCR/5 + MVCR/6. Receiver Operating Characteristic (ROC) analysis showed the Area under the Curve (AUC) for the 6 variables ranged from 0.69 to 0.839. Multivariate k-means clustering analysis showed that Ponte/2 + PSO/3, BDBO/4 + SVCR/5, and MVCR/6 were three comparatively significant clusters, which could be discriminated by pre-operative kyphosis, T-DAR, age and S-DAR., Conclusion: This study showed that osteotomy plan of severe spinal deformity could be determined as follows: Firstly, Ponte/2 + PSO/3 and BDBO/4 + SVCR/5 + MVCR/6 groups can be divided by either T-DAR (cutoff = 28) or the Cobb angle of pre-operative maximum kyphosis (cutoff = 100). Secondly, Ponte/2 + PSO/3 group could be further dichotomized into Ponte/2 and PSO/3 by age (cutoff = 18). Finally, BDBO/4 + SVCR/5 + MVCR/6 group could be divided into BDBO/4 + SVCR/5 and MVCR/6 groups by S-DAR (cutoff = 20)., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: The variance in clinical responses to polyetheretherketone (PEEK) cages with titanium (Ti) and hydroxyapatite (HA) coatings (PEEK-Ti-HA cages) is still not clear. In this study, we aimed to evaluate the radiographic and clinical outcomes of patients undergoing TLIF using PEEK-Ti-HA cages with a particular focus on fusion rate., Methods: A prospective and nonrandomized study was conducted to compare the outcomes of PEEK-Ti-HA cages (group A, n = 32) and uncoated PEEK cages (group B, n = 32). The follow up time was at least 2 years. The radiographic assessments included the regional lordosis (RL), disc height (DH), and fusion rate. The clinical indexes included the Japanese Orthopedic Association (JOA) scores and visual analog scale (VAS) scores (back and leg)., Results: No significant differences were found in the pre- and postoperative RL and DH between Group A and Group B. And RL and DH, even if there were any variance initially, were restored not long after surgery in both groups. Though Group A had a significantly higher fusion rate than group B at 3 months post-surgery (93.7% vs. 75.0%), the fusion rates for the two groups reached the same level (100%) when it comes to the final follow-up. Additionally, differences of VAS and JOA scores for the two groups in general approximate., Conclusions: PEEK-Ti-HA cages, in contrast with uncoated PEEK cages, produced a better fusion rate at 3 months after single-level TLIF. The fusion rates of both groups could get 100% at the final follow-up. PEEK-Ti-HA cages could achieve similar RL, DH, JOA scores and VAS scores in comparison with uncoated PEEK cages post-surgery., (© 2021. The Author(s).)

Background: The purpose of the study was to investigate whether pelvic incidence (PI) will affect the occurrence of PJK in Lenke 5 AIS patients after correction surgery and try to explore a better surgical scheme based on PI., Methods: Lenke 5C AIS patients that underwent correction surgery with a minimum of a 2-year follow-up were identified. Demographic and radiographic data were collected preoperatively, postoperatively, and at the final follow-up. The comparison between the PJK and the Non-PJK group was conducted and the subgroup analysis was performed based on the preoperative value of PI to investigate the potential mechanism of PJK. Clinical assessments were performed using the Scoliosis Research Society (SRS)-22 questionnaire., Results: The mean preoperative Cobb angle of the TL/L curve was 53.4°±8.6. At the final follow-up, the mean TL/L Cobb angle was drastically decreased to 7.3°±6.8 (P < 0.001). The incidence of PJK in Lenke 5 AIS was 18.6 %, 21.9 % (7/32) in the low PI group (PI < 45°) and 15.8 % (6/38) in the high PI group (PI ≥ 45°), and there was no statistical difference between the two groups (χ 2  = 0.425, P = 0.514). For low PI patients, there is no significant difference where the UIV is located with regards to the TK apex between the PJK and Non-PJK subgroups (χ 2  = 1.103, P = 0.401). For high PI patients, PJK was more likely to occur when UIV was cephalad to than caudal to the TK apex (31.25 % vs. 4.7 %, P = 0.038). There was no significant difference in the selection of LIV between the two groups., Conclusions: There is no difference in the incidence of PJK between the Lenke 5 AIS patients with low PI (< 45°) and high PI (≥45°), but the main risk factor of PJK should be different. For patients with low PI, overcorrection of LL should be strictly avoided during surgery. For patients with high PI, the selection of UIV should not be at or cephalad to the apex of thoracic kyphosis to retain more mobile thoracic segments.

Purpose: We previously reported anterior release, posterior internal distraction, and subsequent spinal fusion (ARPIDF) for the correction of severe scoliosis with a satisfactory correction rate. However, surgical procedures were completed in 2-3 stages. Here we compare Cobb angle of ≥90° in scoliosis correction between a novel posterior multiple screws distraction reducer (MSDR) system and ARPIDF., Methods: Thirty-six patients with severe scoliosis treated by MSDR or ARPIDF (n = 18 in both groups). We retrospectively analyzed and compared outcome measures between the two groups over a minimum follow-up duration of 2 years. The following variables were compared between the two groups: age at surgery, sex, etiology, flexibility of the main thoracic curve, number of fused segments and screws, operation time, estimated blood loss, hospitalization time, follow-up duration, various radiological parameters, complication rate, and Scoliosis Research Society-30 score., Results: There were no significant between-group differences with respect to age, sex, etiology, flexibility of the main thoracic curve, number of fused segments and screws, and follow-up duration. Further, there was no significant difference in terms of preoperative, postoperative, and final follow-up findings of the radiographic data. However, the ARPIDF group had longer operation and hospitalization times and greater blood loss. In the ARPIDF group, 4 patient developed complications (infection, intraoperative neuromonitoring changes, transient dyspnea); none of these events occurred in the MSDR group., Conclusion: The use of MSDR helped achieve greater scoliosis correction with a shorter operation time, lower blood loss, and lower complication rate than the use of ARPIDF. MSDR facilitates safer and easier correction of severe scoliosis without increasing surgical risk.

Objective: To compare the predictive abilities of O-C2 angle (O-C2a), O-EA angle (O-EAa), and Oc-Ax angle (Oc-Axa) for development of dysphagia in patients after occipitocervical fusion (OCF)., Methods: Between April 2010 and May 2019, 114 patients who underwent OCF and met the selection criteria were selected as the research objects. Among them, 54 were males and 60 were females; they were 14-76 years old, with an average of 50.6 years old. The follow-up time was 13-122 months (median, 60.5 months). The O-C2a, O-EAa, Oc-Axa, and the narrowest oropharyngeal airway space (nPAS) were measured by the lateral X-ray films before operation and at last follow-up, and the differences before and after operation (dO-C2a, dO-EAa, dOc-Axa, and dnPAS) were calculated. Patients were divided into two groups according to whether they had developed postoperative dysphagia. The general data including age, gender, fixed segment, proportion of patients with rheumatoid arthritis (RA), atlantoaxial subluxation (AS), and combined with anterior release surgery (ARS), and imaging indicators were compared between the two groups. The correlations between dO-C2a, dO-EAa, and dOc-Axa and dnPAS in 114 patients were analyzed to further compare the predictive value of three imaging indicators for occurrence of dysphagia after OCF., Results: Dysphagia occurred after OCF in 31 cases with the incidence of 27.2%. There was significant difference in gender between the dysphagia group and the non-dysphagia group ( χ 2 =7.940, P =0.005). There was no significant difference between the two groups in age, fixed segment, the proportion of patients with RA, the proportion of patients with AS, and the proportion of patients combined with ARS ( P >0.05). There was no significant difference in O-C2a and Oc-Axa of 114 patients before operation and at last follow-up ( P >0.05). The differences in O-EAa and nPAS were significant ( P <0.05). There was no significant difference in preoperative O-EAa, Oc-Axa, and nPAS between the dysphagia group and the non-dysphagia group ( P >0.05); the difference in the O-C2a was significant ( t =2.470, P =0.016). At last follow-up, the differences in the above imaging indicators were significant ( P <0.05). There were significant differences in the dO-C2a, dO-EAa, dOc-Axa, and dnPAS between the two groups ( P <0.05). Correlation analysis showed that the dO-C2a, dO-EAa, dOc-Axa were all positively correlated with dnPAS ( P <0.05). The dO-C2a≤-5°, postoperative O-EAa≤100°, postoperative Oc-Axa≤65° were all related to postoperative dysphagia ( P <0.05), and the highest risk factor suffering postoperative dysphagia was dO-C2a ≤-5° with a significant OR of 14.4., Conclusion: The dO-C2a, postoperative O-EAa, and postoperative Oc-Axa can be used as the predictive indexes of dysphagia after OCF, among which dO-C2a has the highest predictive value.

Background: Currently, there are limited reports regarding investigation of the biological properties of polyetheretherketone (PEEK) coated with titanium (Ti) and hydroxyapatite (HA) in human. The objective of this study is to evaluate the in vivo response of the PEEK cages coated with Ti and HA versus uncoated PEEK cages after anterior cervical discectomy and fusion (ACDF) in patients with single-level cervical degenerative disc disease (CDDD)., Methods: Twenty-four patients with PEEK cages coated with Ti and HA (PEEK/Ti/HA group) were matched one-to-one with patients with uncoated PEEK cages (PEEK group) based on age, gender, and operative segment. All patients had been followed up for more than 2 years. Radiological assessments included intervertebral height (IH), C2-7 angle (C2-7a), segmental alignment (SA), and fusion rate. Clinical parameters included Visual Analogue Scale (VAS) and Japanese Orthopedic Association (JOA) scores., Results: There was no statistical difference in SA, IH, and C2-7a between the two groups before and after surgery and all these parameters were restored postoperatively. The fusion rate of PEEK/Ti/HA group was significantly higher than PEEK group at 3-month post-operation (87.5% vs. 62.5%). At the last follow-up, the fusion rate of the both groups achieved 100%. The VAS and JOA scores were comparable between two groups and improved postoperatively., Conclusions: In patients with single-level ACDF, PEEK cage coated with Ti and HA provided a higher fusion rate than uncoated PEEK cage at 3-month post-operation, while both two cages could achieve solid osseous fusion at the last follow up. Compared with the uncoated PEEK cage, PEEK/Ti/HA cage yielded similar favorable segmental and overall cervical lordosis, IH, and clinical outcomes after the surgery.

Background: The windswept lower limb deformity describes valgus deformity in one leg with varus deformity in the other. It is mostly seen in young children with metabolic bone diseases (such as rickets) and may lead to leg length discrepancy (LLD) and Degenerative scoliosis (DS) in older age. To the best of our knowledge, there was no report of the spinal surgery in patient with severe DS associated with windswept deformity. The objective of this study is to report the unique case of a 60-year-old woman with severe degenerative scoliosis (DS) associated with windswept deformity caused by rickets who underwent a posterior correction and fusion surgery in spine., Case Presentation: The patient was diagnosed as rickets windswept lower limb deformity for 50 years but never went through routine treatment. Then, she performed lumbar scoliosis for more than 20 years and suffered from severe back pain for 4 years. After overall clinical evaluation and radiographic measures, we performed a posterior surgical correction and fusion from T9-L5. With this surgery, the main thoracolumbar curve Cobb angle corrected from 72.5° to 21.0°, the coronal balance from 0 cm to 2.0 cm while the sagittal vertical axis (SVA) from 1.5 cm to - 1.0 cm. At 2 years postoperative follow-up, her back pain has almost completely relieved with a satisfied fixation and bone fusion showed on CT scans. However, a coronal imbalance was found with C7-CSVLdistance equal to 4.0 cm. This coronal imbalance was highly correlated to the untreated LLD and pelvic obliquity, and should be improved by standing posture or shoe lifts., Conclusions: For such patient, the pure spinal correction and fusion surgery, in spite of lower limbs deformity, can achieve good relieve of back pain symptom, however may accompany by the complication of coronal imbalance due to the unimproved pelvic obliquity and LLD. However, longer follow-up is necessary to observe the long-term outcome of this patient's postoperative coronal imbalance.

Objectives: It remains unclear which subgroups of scoliotic patients with CMI and syringomyelia are more likely to undergo unplanned neurosurgery after spinal deformity correction. The purpose of this study is to explore risk factors of unplanned neurosurgery for scoliotic patients with CMI and syringomyelia after spinal deformity correction., Patients and Methods: This cohort consisted of 62 scoliotic patients with CMI and syringomyelia who underwent spinal deformity surgery with a mean follow-up of 4.3 year. 14 of them underwent unplanned neurosurgery (the NN group), and the other 48 patient underwent single spinal correction surgery (the SS group). The radiological parameters were compared between the two groups, and multivariate logistic regression analysis and Kaplan-Meyer survival curves were used to identify potential risk factors of unplanned neurosurgery., Results: The incidence of unplanned neurosurgery after spinal deformity surgery was 22.28 % (14/62), and delayed headache was the most common reason for unplanned neurosurgery with five patients (36 %) and follow by neck pain with three patients (21 %). Significantly increased tonsil ectopia (9.7 ± 3.8 vs. 6.9 ± 2.9; P = 0.021), syrinx/cord width ratio (0.62±0.11 vs. 0.45±0.13; P＜0.001), and syrinx/cord area ratio (0.45 ± 0.11 vs. 0.26 ± 0.15; P＜0.001) were found in the NN group. While, there were no significant differents in pBC2 line, clivus canal angle, and syrinx length between the two groups. The logistic regression analysis indicated that tonsil ectopia≥10 mm (P = 0.019; OR=6.440; 95 %CI = 1.361 to 30.467) and syrinx/cord area ratio ≥ 0.4 (P = 0.006; OR=7.664; 95 %CI = 1.819 to 32.291) were independent risk factors of unplanned neurosurgery. Kaplan-Meyer survival curves showed cumulative unplanned neurosurgery for patients with tonsil ectopia ≥ 10 mm (P < 0.001) and syrinx/cord area ratio ≥ 0.4 (P = 0.001) after spinal deformity correction., Conclusion: After spinal deformity correction, 78 % of the patients did not require later neurosurgery and those that needed it had a delay of more than nine months. Tonsil ectopia ≥ 10 mm and syrinx/cord area ratio ≥ 0.4 were independent risk factor of unplanned neurosurgery after spinal deformity correction. It is reasonable to perform spinal corrective surgery in patients with minimal symptoms and signs without the need for prior neurosurgical intervention., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Purpose: To investigate airway development and airway resistance by computed tomographic three-dimensional (3D) reconstruction of the bronchial tree in patients with adolescent idiopathic scoliosis (AIS). We evaluated factors predicting postoperative respiratory complications to provide timely treatment, prevent complications, and improve operative and anesthetic safety., Methods: From August 2015 to August 2017, 53 AIS patients with a mean age of 15.4 years (range 10-20 years) were included in this study. Scoliotic parameters on radiographs were analyzed. Airway resistance was obtained by pulmonary function testing. All patients' pulmonary bronchial trees were 3D-reconstructed via chest thin layer computed tomography to explore the correlation between the spinal-thoracic deformity parameters and airway resistance., Results: Correlations between scoliotic parameters and airway development parameters were not statistically significant (P > 0.05). The scoliotic parameters such as Cobb angle, apical vertebral translation, rotation angle to sagittal plane, rotation angle to middle line, and apical vertebral body-rib ratio (AVB-R) were positively correlated with tracheal bifurcation angle (R 2 : 0.429, 0.374, 0.430, 0.504, and 0.414, respectively; P < 0.05). Cobb angle, rib hump, and apical vertebral body-rib ratio (AVB-R) were positively correlated with left principal bronchus length to right principal bronchus length (PBL-R) (R 2 : 0.373, 0.503, and 0.377, respectively; P < 0.05). Superficial area of bronchial tree (SABT) and narrow cross section of trachea (NCT) were negatively correlated with plethysmography Pre-Ref resistance ratio (Pre/Ref) (R 2 : - 0.365 and - 0.452, respectively; P < 0.05). SABT and NCT were negatively correlated with respiratory impedance (Zrs) (R 2 : - 0.327 and - 0.436, respectively; P < 0.05)., Conclusions: Pulmonary bronchial development in patients with AIS is affected by spinal-thoracic deformity. Comprehensive assessment of preoperative pulmonary function, especially airway resistance, is necessary in patients with AIS whether the thoracic scoliosis is severe or mild-to-moderate. These slides can be retrieved under Electronic Supplementary Material.

Background Context: Minimally invasive lateral lumbar intervertebral fusion (LLIF) procedure has been reported as a feasible alternative to the traditional anterior approach for patients with lumbar tuberculosis. However, there is still no study in the existing literature comparing LLIF to traditional surgeries in the treatment of such patients., Purpose: To evaluate the clinical, radiological, and functional outcomes of LLIF versus the traditional anterior approach for treating localized lumbar tuberculosis., Study Design: Retrospective case-control study., Patient Sample: A total of 60 patients with single-level localized lumbar tuberculosis., Outcome Measures: The outcome parameters included incision length, operation time, blood loss, complications, segmental lordosis, fusion status, Frankel grade, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), visual analog scale (VAS), and Oswestry Disability Index (ODI)., Methods: We matched 20 patients treated by LLIF with 40 patients undergoing traditional anterior surgery (ratio, 1:2) by age, sex, lesion level, and radiographic features. The LLIF group consisted of 12 men and eight women with a mean age of 42.2±11.1 years, while the traditional group consisted of 22 men and 18 women with a mean age of 40.0±14.5 years. Both the demographics and radiographic data were reviewed. Pre- and postoperative segmental lordosis Cobb angle was measured on lateral X-ray films, while fusion status was assessed on computed tomography scans. The VAS and ODI were used to evaluate functional outcomes., Results: The average follow-up was 24 months in the LLIF group and 39 months in the traditional group. Incision length, operation time, and blood loss were significantly less in the LLIF group than in the traditional group. A similar improvement in segmental lordosis after operation was found in both groups. There was no significant difference between the two groups in neurological recovery, blood infection markers (ESR, CRP), functional outcome, or fusion rate, except for the postoperative VAS score, which was significantly lower in the LLIF group than in the traditional group (2.7±1.0 vs. 3.6±1.0, p=.003). Four patients in the traditional group received a transfusion and 4 patients had a superficial wound infection, while no patient in the LLIF group received a transfusion or experienced any infection; however, the difference between the two groups was not statistically significant (p=.291)., Conclusions: Both LLIF and traditional anterior surgery are sufficient for treating patients with localized lumbar tuberculosis, but the LLIF approach results in significantly shorter operation time and less blood loss., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Objective: The nano-hydroxyapatite/polyamide66 (n-HA/PA66) cage is a novel biomimetic nonmetal cage, whereas the polyetheretherketone (PEEK) cage has been widely used for decades with excellent clinical outcomes. However, there has been no long-term comparison of these 2 cages in anterior cervical reconstruction., Methods: This retrospective study included 98 patients who underwent single-level anterior cervical decompression and fusion (ACDF) from January 2009 to June 2011 with at least 7 years of follow-up; the PEEK cage was used in 51 patients (PEEK group), whereas the n-HA/PA66 cage was used in 47 (n-HA/PA66 group). The groups were compared regarding radiographic (cage subsidence, fusion status, cervical lordosis, and segmental sagittal alignment) and clinical (10-point visual analog scale and Japanese Orthopedic Association scores) parameters preoperatively, postoperatively, and at the final follow-up., Results: The n-HA/PA66 and PEEK cages had similar fusion rates at the final follow-up (97.9% vs. 98.0%). The respective cage subsidence rates in the PEEK and n-HA/PA66 cage groups were 9.8% and 10.6%. There were no significant differences between the 2 groups in mean cervical lordosis, mean interbody height, segmental sagittal alignment, cervical lordosis, and 10-point visual analog scale and Japanese Orthopedic Association scores at the final follow-up. The n-HA/PA66 cages resulted in high fusion and low subsidence rates during long-term follow-up., Conclusions: After single-level ACDF, the n-HA/PA66 cage showed similar radiographic fusion, subsidence rate, and clinical results compared with the PEEK cage during 7 years of follow-up. These results suggest that the n-HA/PA66 cage could be comparable with the PEEK cage for ACDF., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The treatment of congenital hemivertebrae in the upper thoracic region is challenging. The objective of this study was to investigate the outcomes of posterior hemivertebral resection for the upper thoracic region. Twenty-one patients diagnosed with upper thoracic congenital scoliosis were included. All of them received hemivertebral resection surgery via the posterior-only approach with at least 2 years of follow-up. The radiographic parameters and Scoliosis Research Society-22 score were analyzed. All the intraoperative and postoperative complications were recorded retrospectively. The segmental main curve was 35.9° before surgery and 7.0° at the last follow-up, with an average correction rate of 80.2%. The total main curve was 44.1° before surgery and 11.6° at the last follow-up, with an average correction rate of 73.9%. The caudal compensatory curve was corrected from 20.2° to 7.1°, with an average correction rate of 64.9%. The segmental kyphosis was corrected from 30.9° to 8.9°, with an average correction rate of 65.5%. The total Scoliosis Research Society-22 score significantly improved in all patients at the last follow-up, mainly resulting from the improvement of the self-image, mental health, and satisfaction domains. The following complications were found: one pedicle fracture, two malpositioned screws, one transient neurologic deficit, one implant failure, and four postoperative curve progressions. Although good radiographic deformity correction and clinical results were achieved after surgery, the incidence rate of complications was high at 42.9%; great care should be taken to prevent them, especially for postoperative curve progression (19.0%).

Background: Spinal tuberculosis accounts for more than 50% of bone tuberculosis cases. This study compared clinical, radiological and functional outcomes between anterior and posterior approaches for treatment of middle or lower thoracic spinal tuberculosis in elderly patients., Methods: We retrospectively examined middle or lower thoracic spinal tuberculosis (T5-T12) in patients over 65 years. All procedures included debridement, decompression, autologous bone graft and fixation. Surgical procedure, surgical duration, estimated blood loss during surgery and laboratory results were recorded. Pleural effusion volume, thoracic cavity volume, Oswestry Disability Index score, neurological status, radiological parameters and complication rate were evaluated., Results: No significant difference was found in surgical duration, blood loss, kyphosis angle correction, loss of correction, thoracic cavity volume, or complication rate between the two groups (P > 0.05). Average postoperative pleural effusion volumes were 605.9 ± 209.5 mL (377-1074 mL) and 262.9 ± 228.1 mL (0-702.4 mL) in the anterior and posterior groups, respectively (P = 0.004). Average hospitalization durations were 26.4 ± 10.5 days (17-53 days) and 19.2 ± 5.0 days (14-30 days) (P = 0.04). Average postoperative serum albumin levels were 24.19 ± 3.84 g/L (19-29.5 g/L) and 28.24 ± 2.52 g/L (24.4-31.6 g/L) (P = 0.01). No relapse or reinfection was observed in either group at the final follow-up. Surgical revision was not required in either group., Conclusions: Both anterior and posterior surgeries can be used to treat middle or lower thoracic spinal (T5-T12) tuberculosis in elderly patients. In general, the posterior approach might be superior, especially for patients with poor general health., (Copyright © 2018 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.)

Background: Extended fusion can be performed in patients with Lenke 5C adolescent idiopathic scoliosis (AIS) with a large and relatively rigid thoracic curve. Progression of the thoracic curve is related to coronal imbalance. We aimed to determine the correlation between the upper instrumented vertebra choice and coronal balance in patients with Lenke 5C AIS., Methods: A total of 61 patients with Lenke 5C AIS underwent posterior fusion from 2009 to 2015 in a single institution with ≥2 years of follow-up data available. The extended fusion group (n = 32) and thoracolumbar/lumbar (TL/L) fusion group (n = 29) were compared for the correction rates for the main TL/L and thoracic curves, coronal balance, upper end vertebra (UEV) tilt, and Scoliosis Research Society-22 questionnaire score., Results: Both groups had excellent correction of the main TL/L curve, and the extended fusion group had a significantly greater correction rate of the thoracic curve than the TL/L fusion group (70.2% vs. 57.3%). The incidence of coronal imbalance was similar in both groups. The spontaneous change in UEV tilt was associated with the change in coronal balance from the first to the final follow-up examination. In the TL/L fusion group, the increase in UEV tilt from the first to final follow-up visit resulted in improved coronal balance at the final follow-up examination. Both groups had similar Scoliosis Research Society-22 questionnaire scores at 2 years postoperatively., Conclusions: In patients with Lenke 5C AIS, thoracic curve fusion results in better correction of the thoracic curve but no improvement in coronal balance. With TL/L fusion, a postoperative UEV tilt >5° leads to better coronal balance., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Hemimetameric segmental shift (HMMS) is defined as ≥2 contralateral hemivertebrae (HV) that are separated by at least 1 normal vertebra. Theoretically, the 2 HV tend to balance each other to produce minor spine deformities. However, curve progression has still been observed in HMMS. No research has yet specifically studied its surgical treatment. This study aimed to report efficacy of HV resection for HMMS., Methods: From 2009 to 2015, 15 patients (5 male and 10 female) with HMMS underwent HV resection in our department. Average age at the time of surgery was 10.5 ± 4.7 years, and mean length of follow-up was 38.5 ± 7.1 months. Clinical outcomes and related complications were assessed by reviewing the medical records, operative notes, radiographic data, and scores on the Scoliosis Research Society-22 questionnaire., Results: The segmental curve was 45.1° ± 10.6° preoperatively, 14.3° ± 7.8° postoperatively, and 15.3° ± 7.6° at the latest follow-up. The cranial compensatory curve was 17.1° ± 11.9°, 8.9° ± 6.3°, and 7.8° ± 6.5°. The caudal compensatory curve was 12.0° ± 11.0°, 4.5° ± 4.8°, and 4.3° ± 5.0°. Spinal balance was significantly improved in both coronal and sagittal planes and remained stable until the latest follow-up. Three domains of the Scoliosis Research Society-22 questionnaire, including general self-image, mental health, and satisfaction, were significantly improved at the latest follow-up compared with preoperative status., Conclusions: HV resection is a safe and effective treatment for HMMS that causes progressive or severe deformity., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background Context: Treatment guidelines for severe and rigid syringomyelia-associated scoliosis (SRSMS) are limited. Typically, surgeons apply practice guidelines for severe and rigid idiopathic scoliosis (SRIS) to treat SRSMS. No study has directly compared the results of surgical treatment between patients with SRSMS and those with SRIS., Purpose: The present study was performed to compare the outcomes of surgical correction of SRSMS and SRIS from clinical and radiographic perspectives., Study Design: This is a retrospective, case-matched, single-center, institutional review board-approved study., Patient Sample: A total of 26 patients with SRSMS or SRIS treated by an anterior and posterior vertebral column resection approach or an internal distraction approach were enrolled., Outcome Measures: The SRSMS and SRIS groups were compared on the following variables: fusion length, screw number, operation time, estimated blood loss, follow-up duration, different radiological parameters (including main thoracic curve, cranial compensatory curve, caudal compensatory curve, thoracic kyphosis, lumbar lordosis, thoracic apical vertebral translation, coronal balance, and sagittal vertical axis), Scoliosis Research Society (SRS)-22 scores, and complication rate., Methods: Thirteen patients with SRSMS were matched with patients with SRIS on curve magnitude, the flexibility of the main curve, surgical procedure, age, and gender. All patients had a minimum of 2 years of follow-up. The radiographic parameters and demographic data from patients were evaluated before surgery, immediately after surgery, and at the latest follow-up., Results: The case matches were relatively ideal except one pair with the main curve in the opposite direction. There was no significant difference in fusion length, screw number, operation time, estimated blood loss, or follow-up duration between the two groups. No significant differences were found between the two groups in the main curve or caudal compensatory curve before surgery, immediately after the operation, or at the final follow-up. The correction of thoracic apical vertebral translation in the SRIS group was better than that in the SRSMS group. The SRSMS group had a larger preoperative, postoperative, and final follow-up cranial compensatory curve and a lower correction rate than did the SRIS group. There was no significant difference in preoperative coronal balance between the two groups. After surgery, the coronal balance in the SRSMS and SRIS groups averaged 24.4±13.2 mm and 12.1±7.9 mm, respectively, which was significantly different (p=.04). At the most recent follow-up, the coronal balance in the SRSMS group improved to 14.8±12.6 mm, and it was 11.8±8.6 mm in the SRIS group. No significant difference was found between the two groups (p=.56). There was no significant difference in thoracic kyphosis, lumbar lordosis, or sagittal vertical axis before surgery, immediately after the operation, or at the final follow-up. Before surgery and at the final follow-up, the two groups had similar scores on function, pain, self-image, mental health, and satisfaction. There was no significant difference in complication rates between the two groups., Conclusions: Typically, surgical correction outcomes are similar in patients with SRSMS and SRIS. Patients with SRIS tended to have a smaller cranial compensatory curve and better correction of the cranial compensatory curve and thoracic apical vertebral translation. Patients with SRSMS tended to have a higher proportion and greater amount of postoperative coronal imbalance, which may be improved during follow-up., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Objective: To discuss the effectiveness of atlantoaxial joint release through anterior retrophayngeal approach and staged posterior reduction fixation and fusion for irreducible atlantoaxial dislocation (IAAD)., Methods: Fifteen patients with IAAD (9 males, 6 females), aged 14-53 years (mean, 31.4 years) were included in the study. The disease duration was 3 months to 17 years (mean, 5.7 years). IAAD was attributed to trauma in 13 cases, and 2 cases were caused by congenital odontoid disconnection. Preoperative imaging examination showed atlantoaxial dislocation and could not be reset automatically in functional position. The preoperative visual analogue scale (VAS) score was 3-7 (mean, 4.1), and the preoperative Japanese Orthopaedic Association (JOA) score was 10-17 (mean, 13.8). All patients received atlantoaxial joint release through anterior retrophayngeal approach and staged posterior fixation and fusion., Results: Anatomical reduction was achieved in all 15 patients, and the alignment of atlantoaxial joints was restored. After operation, the neck pain and neurological symptom were partially or fully improved in all patients, without deterioration of neurological function. One patient developed pharyngeal discomfort and cough after one-stage operation, 4 patients developed pharyngeal discomfort and foreign body sensation after operation, and 2 patients developed pin-path lipstick swelling during skull traction. All patients were cured by symptomatic treatment. No pulmonary infection, pressure ulcers, venous thrombosis, and incision infection was found during the treatment. All 15 patients were followed up 24-36 months, with an average of 28.6 months. Bony fusion was achieved in all patients, and the fusion time was 3-5 months, with an average of 3.6 months. At last follow-up, the VAS score was 0-2 (mean, 0.5) and the JOA score was 13-17 (mean, 15.9). There was no dislocation, recurrence, or other abnormal sign in the cervical X-ray films and three-dimensional CT., Conclusion: Anatomical reduction can be achieved by atlantoaxial joint release through anterior retrophayngeal approach and staged posterior fixation and fusion for treating IAAD. It is an optional procedure for IAAD.

Background: Choosing the fusion level for posterior fusion in patients with Lenke 5C adolescent idiopathic scoliosis (AIS) is highly associated with coronal balance. Previous studies indicated that in patients with lowest end vertebra tilt >25°, surgeons could extend distal fusion to avoid coronal imbalance (CIB). This study aimed to assess the risk factors for CIB in Lenke 5C scoliosis and to discuss how to select fusion level., Methods: We reviewed 59 patients with Lenke 5C AIS in 1 institution with at least 2 years follow-up from 2010 to 2015. Preoperative and 3-month and 2-year postoperative follow-up radiographs were measured using several specific measurements related to coronal balance. Patients were categorized into an LEV (lower end vertebra) group and an LEV+1 group., Results: CIB was found in 6/31 patients in the LEV+1 group at final follow-up and not found in the LEV group at the first or final follow-up. The C7 plumb line shifted to the convex side of the central sacral vertical line in 47/59 patients, including all of the 19 patients with CIB after surgery. Patients who underwent fusion at LEV+1 with >25° LEV tilt also showed poor results regarding CIB. Statistically, coronal balance at the final follow-up was correlated with preoperative bending lumbosacral hemicurve (P = 0.002) and all 6 patients with CIB had bending lumbosacral hemicurve >15°. No significant difference was found in Scoliosis Research Society-22 questionnaire scores between the 2 groups at 2-year-follow-up., Conclusions: Distal fusion extension at LEV+1 is more likely to result in CIB at the first and final follow-up, especially when the bending lumbosacral hemicurve is >15°. Fusion at LEV+1 should not be chosen when LEV is at L4., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Lenke 5 AIS is a kind of three-dimensional deformity and literature reported it usually accompany with coronal or/and sagittal imbalance. However, the postoperative coronal and sagittal balance in these patients has rarely be analyzed previously and the predict factors for postoperative trunk balance are still unclear. To synthetically analysis coronal and sagittal balance of Lenke 5 AIS patients simultaneously and found out predict factors for postoperative coronal or/and sagittal imbalance., Methods: Fifty-six Lenke 5 AIS patients who underwent posterior surgery and be followed up more than 2 years were included in this study. Coronal parameters included main curve Cobb angle, lumbosacral hemi-curve Cobb angle, preoperative LEV/LIV tilt and translation and C7-CSVL distance; While sagittal parameters included pelvic incidence(PI), sacral slope(SS), pelvic tilt(PT), lumbar lordosis(LL), thoracic kyphosis(TK), and sagittal vertical axis(SVA). Coronal imbalance was defined as C7-CSVL> 20 mm, and sagittal imbalance defined as (1) SVA > 40 mm or (2) PT < 20% PI/2 or PT > 20° or (3) PI-LL > 10°. And relative parameters were compared between balance and imbalance group to find out predict factors., Results: All seven final coronal imbalance patients occurred in LIV = L5 group. Preoperative LIV tilt(11.4°) and translation(5.2 mm) in coronal imbalance group were abnormally lower than balance group (21.7° and 15.7 mm respectively). Eighteen patients performed final sagittal imbalance. The PI in these patients (37.7°) was significantly lower than balance group (48.0°). And most of finial sagittal imbalance patients also occurred in LIV = L5 group., Conclusions: LIV = L5 as a threshold point, represents higher risk of postoperative coronal and/or sagittal imbalance. Besides, large LEV-S1 curve in reduce-bending film and small PI is directly related to final coronal imbalance and sagittal imbalance respectively.

Background Context: Many different correction methods have been reported to treat severe and rigid scoliosis. In the past, anterior and posterior spinal fusion (APSF), which included an anterior release followed by posterior instrumented fusion, was widely applied. In recent years, anterior/posterior vertebral column resection (APVCR) is used to treat severe and rigid scoliosis., Purpose: We aimed to compare the clinical results of APSF and APVCR for severe and rigid scoliosis., Study Design: This is a retrospective, one-center, institutional review board-approved study., Patient Sample: A total of 48 patients with severe and rigid scoliosis treated by APSF or APVCR were enrolled., Outcome Measures: Comparisons between groups were made regarding the following variables: age at surgery, gender, etiology, flexibility of main curve, anterior release length, posterior fusion length, screw number, operation time, estimated blood loss, hospitalization time, follow-up duration, different radiological parameters, complication rate, and Scoliosis Research Society (SRS)-22 scores., Methods: According to the operating technique, 48 patients with severe and rigid scoliosis were divided into two groups. In the first group, 26 patients were treated by APSF. In the second group, 22 patients were treated by APVCR. All patients had a minimum 2-year follow-up. The radiographic parameters as well as anterior release length, posterior fusion length, screw number, operation time, estimated blood loss, hospitalization time, complication rate, and demographic data were analyzed., Results: There was no significant difference in age, gender, etiology, flexibility of main curve, anterior release length, posterior fusion length, screw number, and follow-up between the two groups. The APVCR group had longer operation and hospitalization time, and more blood loss. There was no significant difference in the preoperative main curve between the two groups, but the APVCR group had smaller main curve at postoperation and final follow-up, and higher correction rate at immediate postoperation and final follow-up. There was no significant difference in the preoperative, postoperative, and final follow-up thoracic kyphosis, and coronal and sagittal balance between the two groups. There was no significant difference in complication rate between the two groups. Analysis of the preoperative SRS-22 questionnaire revealed no difference between the two groups. At final follow-up, APSF and APVCR groups had similar scores in the function, pain, self-image, mental health, and satisfaction with the treatment domains., Conclusions: Compared with APSF, treating severe and rigid scoliosis by APVCR means longer operation and hospitalization time, and more blood loss, but it allows better correction rate of main curve. Furthermore, SRS-22 questionnaire improvement scores were similar for both correction methods., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background Context: Atlantoaxial fixation with C1 lateral mass-C2 translaminar bicortical (C1LM-C2TB) screws has been reported to afford good stability with the least risk of injury to vertebral artery. However, no comparative in vitro studies have been conducted to evaluate the biomechanical stability of this method., Purpose: This study aimed to compare in vitro biomechanics of fixation with C1LM-C2TB with fixation with C1 lateral mass-C2 translaminar unicortical screws (C1LM-C2TU) and with C1 lateral mass-C2 pedicle screws (C1LM-C2PS)., Study Design: This is an in vitro biomechanical study., Methods: Fifteen fresh-frozen human cadaveric cervical spines (C1-C3) were tested after destabilization by transverse-alar-apical ligament disruption. Instrumentation was performed with three fixation constructs: C1LM-C2PS, C1LM-C2TU, and C1LM-C2TB. Flexion, extension, lateral bending, and axial rotation were tested. Range of motion and neutral zone pre-fatigue and post-fatigue values were measured., Results: No significant differences were observed in flexion-extension among the three groups. However, C1LM-C2TB fixation was superior to C1LM-C2TU fixation in lateral bending and axial rotation., Conclusion: C2 translaminar bicortical screws are biomechanically superior to C2TU screws for fixation of the atlantoaxial complex, and it is equivalent to C2PS fixation. C2 translaminar bicortical screws or C2PS should be preferred over C2TU screws., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Rationale: Tuberculous aortic pseudoaneurysm associated with vertebral tuberculosis is a rare disease but with very high mortality. We review the literature and find 19 reports with 22 patients. Here we report three cases with vertebral tuberculosis, who also have tuberculous pseudoaneurysm of the aorta. These patients were treated by different methods. We try to analyze the epidemiology, pathogenesis, presentation, and management of this disease to find the best treatment., Patient Concerns: The patients presented with different symptoms such as pain (chest, abdominal or back), fever, blood volume reduction or hemorrhagic shock symptoms. Large mass also could be observed by imaging. In addition to clinical manifestations, enhanced computed tomography or magnetic resonance imaging could also help the diagnosis of this disease., Diagnoses: Tuberculous aortic pseudoaneurysm associated with vertebral tuberculosis., Interventions: Three patients were treated with anti-tuberculosis(TB) drugs or combined with different sequences surgical treatment: Case 1 refused to receive pseudoaneurysm surgery and only had anti-TB drug treatment; Case 2 received thoracic spinal surgery first; Case 3 received endovascular stent grafting., Outcomes: Two patients (case 1 and case 2) who refused to undergo aneurysm surgery died. The last patient (case 3) underwent endovascular repair and antibiotic therapy for tuberculosis, and the postoperative course was uneventful; the patient recovered and survived., Lessons: Once the diagnosis of tuberculous pseudoaneurysm is confirmed, surgical treatment should be provided immediately combined with anti-tuberculosis drugs. The aim of the treatment is to save lives, prevent relapse, and facilitate the return to normal life, regardless of the size of the pseudoaneurysm. The pseudoaneurysm should be treated first to prevent aneurysm rupture before the vertebral tuberculosis surgery.

Objective: Hemivertebrae (HV) located at the lower lumbar or lumbosacral region often produce early trunk imbalance and long compensatory curves. Because of the biomechanical characteristics of the lumbosacral junction, the rate of instrumentation failures at the region has always been high. Our study aimed to evaluate the results of posterior HV resection with lumbosacral fixation and fusion in the treatment of congenital scoliosis and to make a preliminary analysis of the possible risk factors for instrument failures., Patients and Methods: From 2010 to 2015, 17 patients (7 males and 10 females) with congenital scoliosis underwent HV resection with lumbosacral fixation and fusion in our department. The mean patient age was 13.2±4.4years at surgery, and the mean follow-up time was 37.6±4.6months. Clinical outcomes and related complications were assessed by reviewing medical records, operative notes, radiographic data, and scores on the SRS-22 questionnaire., Results: The mean Cobb angle of the segmental curve was 37.5°±12.7° preoperatively, 7.9°±5.5° postoperatively, and 7.9°±5.3° at the latest follow-up. The mean Cobb angle of the cranial compensatory curve was 39.2°±17.2°, 9.1°±9.5°, and 9.5°±10.8°, respectively. Trunk balance was improved in both the coronal (59.6%) and sagittal (58.6%) planes after surgery, and remained stable at the latest follow-up. Three domains of SRS-22, including self-image, mental health, and satisfaction, were significantly improved at the latest follow-up compared with preoperative status. Complications included one transient neurologic impairment, one superficial wound infection, and two implant failures., Conclusions: Early posterior HV resection with short lumbosacral fixation and fusion is effective in the treatment of HV located at lower lumbar or lumbosacral region. Delayed surgical intervention may lead to longer fusion and fixation. A long lumbosacral construct using only S1 pedicle screws as distal anchors tends to accompany a high rate of implant failures., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Background Context: The efficacy of one-stage posterior pedicle screw instrument used in the treatment of non-dystrophic scoliosis in neurofibromatosis type I (NF-1) is unknown. Also, there is no study that has directly compared the results of spinal deformity correction between non-dystrophic scoliosis in NF-1 and adolescent idiopathic scoliosis (AIS)., Purpose: The objectives of this study were to study the efficacy of a one-stage posterior pedicle screw instrument used in the treatment of non-dystrophic scoliosis in NF-1 and to compare non-dystrophic scoliosis in NF-1 with matched AIS to illustrate the differences., Study Design: This is a retrospective case control study., Patient Sample: Fifteen patients with non-dystrophic scoliosis in NF-1 and 15 patients with AIS underwent a one-stage posterior surgery with the pedicle screw system., Outcome Measures: Preoperative and postoperative whole-spine radiographs were used to determine coronal and sagittal Cobb angles. Also, the distance between the C7 plumb line and the center sacral vertical line and the sagittal vertebral axis was measured to assess spinal balance. The Scoliosis Research Society (SRS)-22 questionnaire was used to evaluate functional outcomes., Methods: We matched 15 patients with non-dystrophic scoliosis in NF-1 with patients with AIS (ratio, 1:1) for age, sex, and degree of major deformity. The overall mean age was 13.4±2.0 and 14.0±2.1 years, respectively. The NF-1 group consisted of 10 boys and 5 girls, and the AIS group consisted of 9 boys and 6 girls. The mean follow-up was 37.6±3.9 and 33.5±5.0 months, respectively. The AIS group underwent end vertebra (EV) or EV+1 fusion. The NF-1 group underwent EV+1, 2, or 3 fusion. Both coronal and sagittal Cobb angles, trunk balance, operative time, blood loss, fusion levels, length of stay, and scores on the SRS-22 questionnaire were compared between the two groups. The study was supported by the National Natural Science Foundation of China (Grant No. 81401760). There were no study-specific conflict of interest-associated biases., Results: The preoperative main curve magnitude was similar between the two groups; however, the flexibility of the NF-1 group tended to be less than that of the AIS group. The rate of correction of the main curve obtained surgically (79.8% compared with 81.1%) was similar in the NF-1 and AIS groups. There were no significant differences in the loss of correction between the two groups (p>.05). Also, there were no significant differences between the groups in operative time, blood loss, fusion levels, screw number, length of stay, trunk balance, and scores on the SRS-22. There were no serious complications related to surgery in both groups., Conclusions: Despite the differences in preoperative flexibilities and fusion strategies, non-dystrophic scoliosis in NF-1 can be treated with a satisfied correction rate and progression rate similar to comparable AIS by using the one-stage posterior pedicle screw technique. Dural ectasia or thin pedicles in non-dystrophic scoliosis could make pedicle screw placement challenging., (Copyright © 2017 Elsevier Inc. All rights reserved.)