Kalman-Based Scene Flow Estimation for Point Cloud Densification and 3D Object Detection in Dynamic Scenes.

Point cloud densification is essential for understanding the 3D environment. It provides crucial structural and semantic information for downstream tasks such as 3D object detection and tracking. However, existing registration-based methods struggle with dynamic targets due to the incompleteness and deformation of point clouds. To address this challenge, we propose a Kalman-based scene flow estimation method for point cloud densification and 3D object detection in dynamic scenes. Our method effectively tackles the issue of localization errors in scene flow estimation and enhances the accuracy and precision of shape completion. Specifically, we introduce a Kalman filter to correct the dynamic target's position while estimating long sequence scene flow. This approach helps eliminate the cumulative localization error during the scene flow estimation process. Extended experiments on the KITTI 3D tracking dataset demonstrate that our method significantly improves the performance of LiDAR-only detectors, achieving superior results compared to the baselines.

Construction of circ_0071922-miR-15a-5p-mRNA network in intervertebral disc degeneration by RNA-sequencing.

Background: Low back pain (LBP) is the main factor of global disease burden. Intervertebral disc degeneration (IVDD) has long been known as the leading reason of LBP. Increasing studies have verified that circular RNAs (circRNAs)-microRNAs (miRNAs)-mRNAs network is widely involved in the pathological processes of IVDD. However, no study was made to demonstrate the circRNAs-mediated ferroptosis, oxidative stress, extracellular matrix metabolism, and immune response in IVDD. Methods: We collected 3 normal and 3 degenerative nucleus pulposus tissues to conduct RNA-sequencing to identify the key circRNAs and miRNAs in IVDD. Bioinformatics analysis was then conducted to construct circRNAs-miRNAs-mRNAs interaction network associated with ferroptosis, oxidative stress, extracellular matrix metabolism, and immune response. We also performed animal experiments to validate the therapeutic effects of key circRNAs in IVDD. Results: We found that circ_0015435 was most obviously upregulated and circ_0071922 was most obviously downregulated in IVDD using RNA-sequencing. Then we observed that hsa-miR-15a-5p was the key downstream of circ_0071922, and hsa-miR-15a-5p was the top upregulated miRNA in IVDD. Bioinformatics analysis was conducted to predict that 56 immunity-related genes, 29 ferroptosis-related genes, 23 oxidative stress-related genes and 8 ECM-related genes are the targets mRNAs of hsa-miR-15a-5p. Then we constructed a ceRNA network encompassing 24 circRNAs, 6 miRNAs, and 101 mRNAs. Additionally, we demonstrated that overexpression of circ_0071922 can alleviate IVDD progression in a rat model. Conclusions: The findings of this study suggested that circ_0071922-miR-15a-5p-mRNA signaling network might affect IVDD by modulating the nucleus pulposus cells ferroptosis, oxidative stress, ECM metabolism, and immune response, which is an effective therapeutic targets of IVDD.

Paraspinal muscle degeneration and lower bone mineral density as predictors of proximal junctional kyphosis in elderly patients with degenerative spinal diseases: a propensity score matched case-control analysis.

STUDY DESIGN: Retrospective case-control study. OBJECTIVES: Proximal junctional kyphosis (PJK) is a postoperative complication involving the proximal segments which is commonly seen in patients with degenerative spine diseases (DSD). The purpose of the present study was to identify predictive factors for postoperative PJK in elderly patients with DSD. METHODS: We reviewed elderly patients with DSD who underwent thoracolumbar fusion involving no less than 3 levels. Patients who developed PJK were propensity score-matched with patients with DSD who received the same procedure but did not develop PJK. Demographic characteristics, sagittal vertical axis (SVA), computed tomography (CT) value (Hounsfield unit), and paraspinal muscle parameters were compared between PJK and non-PJK groups. RESULTS: Eighty-three PJK and non-PJK patients were selected by propensity score matching for age, sex, history of smoking, body mass index, number of fused segments, and upper instrumented vertebra (UIV) location. SVA showed no significant difference between the two groups. In PJK group, fatty infiltration (FI) in erector spinae and multifidus was significantly greater, while the relative cross-sectional area (rCSA) of erector spinae was significantly smaller than that in non-PJK group. CT value was significantly lower in PJK group. Lower erector spinae rCSA and CT value of the UIV, higher erector spinae FI and multifidus FI were identified as predictors of postoperative PJK. CONCLUSIONS: PJK is a common complication in older patients with DSD. Paraspinal muscle degeneration and low bone mineral density of the UIV are predictors of PJK. Protective measures targeting paraspinal muscles and the UIV may help prevent postoperative PJK.

Identification of differentially expressed genes in mouse paraspinal muscle in response to microgravity.

Lower back pain (LBP) is the primary reason leading to dyskinesia in patients, which can be experienced by people of all ages. Increasing evidence have revealed that paraspinal muscle (PSM) degeneration (PSMD) is a causative contributor to LBP. Current research revealed that fatty infiltration, tissue fibrosis, and muscle atrophy are the characteristic pathological alterations of PSMD, and muscle atrophy is associated with abnormally elevated oxidative stress, reactive oxygen species (ROS) and inflammation. Interestingly, microgravity can induce PSMD and LBP. However, studies on the molecular mechanism of microgravity in the induction of PSMD are strongly limited. This study identified 23 differentially expressed genes (DEGs) in the PSM (longissimus dorsi) of mice which were flown aboard the Bion M1 biosatellite in microgravity by bioinformatics analysis. Then, we performed protein-protein interaction, Gene Ontology function, and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis for the DEGs. We found that Il6ra, Tnfaip2, Myo5a, Sesn1, Lcn2, Lrg1, and Pik3r1 were inflammatory genes; Fbox32, Cdkn1a, Sesn1, and Mafb were associated with muscle atrophy; Cdkn1a, Sesn1, Lcn2, and Net1 were associated with ROS; and Sesn1 and Net1 were linked to oxidative stress. Furthermore, Lcn2, Fbxo32, Cdkn1a, Pik3r1, Sesn1, Net1, Il6ra, Myo5a, Lrg1, and Pfkfb3 were remarkably upregulated, whereas Tnfaip2 and Mafb were remarkably downregulated in PSMD, suggesting that they might play a significant role in regulating the occurrence and development of PSMD. These findings provide theoretical basis and therapeutic targets for the treatment of PSMD.

Different degeneration patterns of paraspinal muscles in degenerative lumbar diseases: a MRI analysis of 154 patients.

STUDY DESIGN: A retrospective study. OBJECTIVE: To evaluate the different degeneration patterns of paraspinal muscles in degenerative lumbar diseases and their correlation with lumbar spine degeneration severity. The degeneration characteristics of different paraspinal muscles in degenerative lumbar diseases remain unclear. METHODS: 78 patients diagnosed with single-level degenerative lumbar spondylolisthesis (DLS) and 76 patients with degenerative lumbar kyphosis (DLK) were included as DLS and DLK groups. Paraspinal muscle parameters of psoas major (PS), erector spinae (ES) and multifidus muscle (MF) were measured, including fatty infiltration (FI) and relative cross-sectional area (rCSA), namely the ratio of the paraspinal muscle CSA to the CSA of the vertebrae of the same segment. Sagittal parameters including lumbar lordosis (LL) and sagittal vertical axis (SVA) were measured. The paraspinal muscle parameters and ES/MF rCSA ratio were compared between the two groups. Paraspinal muscles parameters including rCSA and FI were also compared between each segments from L1 to L5 in both DLS and DLK groups. In order to determine the influence of sagittal spinal alignment on paraspinal muscle parameters, correlation analysis was conducted between the MF, ES, PS rCSA and FI and the LL in DLS and DLK group. RESULT: MF atrophy is more significant in DLS patients compared with DLK. Also, MF fatty infiltration in the lower lumbar spine of DLS patients was greater compared to DLK patients. DLK patients showed more significant atrophy of ES and heavier ES fatty infiltration. MF FI was significantly different between all adjacent segments in both DLS and DLK groups. In DLS group, ES FI was significantly different between L2/L3 to L3/L4 and L4/L5 to L5/S1, while in DLK group, the difference of ES FI between all adjacent segments was not significant, and ES FI was found negatively correlated with LL. CONCLUSIONS: Paraspinal muscles show different degeneration patterns in degenerative lumbar diseases. MF degeneration is segmental in both DLS and DLK patients, while ES degenerated diffusely in DLK patients and correlated with the severity of kyphosis. MF degeneration is more significant in the DLS group, while ES degeneration is more significant in DLK patients. MF is the stabilizer of the lumbar spine segments, while the ES tends to maintain the spinal sagittal balance.

Pathological Features and Surgical Strategies of Cervical Deformity.

Cervical deformity (CD) is a kind of disorder influencing cervical alignment. Although the incidence of CD is not high, this deformity can cause not only pain but also difficulties in daily activities such as swallowing and maintaining upright position. Even though the common cause of cervical deformity is still controversial, previous studies divided CD into congenital deformity and secondary deformity; secondary deformity includes iatrogenic and noniatrogenic deformity according to pathogenic factors. Due to the lack of relevant studies, a standardized evaluation for CD is absent. Even though the assessment of preoperative condition and surgical planning mainly rely on personal experience, the evaluation methods could still be summarized from previous studies. The objective in this article is to summarize studies on cervical scoliosis, identify clinical problems, and provide directions for researchers interested in delving deep into this specific topic. In this review, we found that the lack of standard classification system could lead to an absence of clinical guidance; in addition, the osseous landmarks and vascular distributions could be variable in CD patients, which might cause the risk of vascular or neurological complications; furthermore, multiple deformities were usually presented in CD patients, which might cause chain reaction after the correction of CD; this would prevent surgeons from choosing realignment surgery that is effective but risky.

Comparison between topping-off technology and posterior lumbar interbody fusion in the treatment of chronic low back pain: A meta-analysis.

BACKGROUND: The difference between topping-off technique and posterior lumbar interbody fusion (PLIF) in postoperative outcomes is still controversial. The aim of this study is to compare all available data on outcomes of topping-off technique and PLIF in the treatment of chronic low back pain. METHODS: Articles in PubMed, EMBASE and Cochrane were reviewed. Parameters included radiographical adjacent segment disease (RASD), clinical adjacent segment disease, range of motion (ROM), global lumbar lordosis (GLL), visual analog scale (VAS), visual analog scale of back, (VAS-B) and visual analog scale leg (VAS-L), Oswestry disability index, Japanese Orthopaedic Association (JOA) score, duration of surgery, estimated blood loss (EBL), reoperation rates, complication rates. RESULTS: Rates of proximal RASD (P = .001) and CASD (P = .03), postoperative VAS-B (P = .0001) were significantly lower in topping-off group than that in PLIF group. There was no significant difference in distal RASD (P = .07), postoperative GLL (P = .71), postoperative upper intervertebral ROM (P = .19), postoperative VAS-L (P = .08), DOI (P = .30), postoperative JOA (P = .18), EBL (P = .21) and duration of surgery (P = .49), reoperation rate (P = .16), complication rates (P = .31) between topping-off group and PLIF. CONCLUSIONS: Topping-off can effectively prevent the adjacent segment disease from progressing after lumbar internal fixation, which is be more effective in proximal segments. Topping-off technique was more effective in improving subjective feelings of patents rather than objective motor functions. However, no significant difference between topping-off technique and PLIF can be found in the rates of complications.

The ratio of C2-C7 Cobb angle to T1 slope is an effective parameter for the selection of posterior surgical approach for patients with multisegmental cervical spondylotic myelopathy.

BACKGROUND: To our knowledge, laminectomy with fusion (LCF) and laminoplasty alone (LP) are both effective posterior surgical approaches for decompression of cervical spondylotic myelopathy (CSM). However, which one is suitable for patients has no standard answer. This study estimated whether the ratio of C2-C7 Cobb angle to T1 slope (CL/T1S) could be an indication of posterior surgical approach. METHODS: We retrospectively reviewed 128 patients with at least 6 months of follow-up who underwent LCF or LP. Radiological measurements, including C2-C7 Cobb angle, decompressed Cobb angle, T1 slope, cervical sagittal vertical axis, and curvature index (CI), and clinical outcomes, including Japanese Orthopedic Association score and visual analogue scale were evaluated. ROC curve analysis was used to identify discriminative power of CL/T1S ratio to predict kyphotic deformity and severe lordosis loss. The t-test and Mann-Whitney U-test were used to evaluate the difference between LCF and LP. Kruskal-Wallis H - test and ANOVA were used to evaluate the difference among different ratio CL/T1S groups. RESULTS: The cervical lordosis decreased after LCF or LP (p < 0.001, p < 0.001, respectively). Based on ROC curve analysis, CL/T1S ratio had a good discriminative power to predict kyphotic deformity and severe lordosis loss (AUC = 0.70, AUC = 0.88, respectively). According to CI value changes, cervical lordosis losses in group LP were larger than that in group LCF (p = 0.006). However, there was no significant difference in CI changes of fair-ratio CL/T1S group between LCF and LP. For patients with low CL/T1S ratio or high CL/T1S ratio, CI changes in group LP were greater than that in group LCF (p = 0.037, p = 0.042, respectively). CONCLUSIONS: CL/T1S ratio could be an indication of posterior surgical approach. Compared with LP, LCF reduces postoperative cervical lordosis losses in low-ratio and high-ratio CL/T1S groups.

A new lever reduction technique for the surgical treatment of elderly patients with lumbar degenerative Spondylolisthesis.

BACKGROUND: Proper reduction method for Lumbar degenerative spondylolisthesis (LDS) is still controversial. The aim of this study was to determine the safety and effectiveness of lever reduction combined with traditional elevating-pull reduction technique for the treatment of elderly patients with LDS. METHODS: From May 2015 to December 2017, 142 elderly patients (≥65 years) diagnosed with LDS were enrolled in this study with a mean follow-up of 25.42 ± 8.31 months. All patients were operated using lever reduction combined with traditional elevating-pull reduction technique. Patient age, sex, body mass index, bone mineral density, preoperative comorbidities, surgical duration, blood loss, and surgical complications were collected form patient charts. Clinical data as visual analog scale (VAS), Oswestry Disability Index (ODI), and 36-Item Short Form Health Survey (SF-36) were collected preoperatively, 1 month postoperatively, and at the final follow-up. Radiographic evaluation included slip percentage, slip angle (SA), lumbar lordosis (LL), and fusion status. RESULTS: The clinical parameters of VASback, VASleg, ODI, and SF-36 had significantly improved at both follow-ups after surgery. A significant improvement was indicated for slippage reduction at both follow-ups, showing no significant correction loss after surgery. SA significantly increased after surgery and was well maintained at the final follow-up. LL was not affected by the surgery. At the final follow-up, complete fusion was obtained in 121 patients (85.2%) and partial fusion in 21 (14.8%). Revision surgery was performed for one patient. Screw loosening was observed in 3 (2.11%) cases. No nerve root injury or adjacent segment disease was observed. CONCLUSIONS: This new lever reduction combined with traditional elevating-pull reduction technique for the surgical treatment of elderly patients with LDS is both safe and effective. Satisfactory correction and fusion rates were achieved with acceptable correction loss and reduction-related complications.

Correlation between multifidus muscle atrophy, spinopelvic parameters, and severity of deformity in patients with adult degenerative scoliosis: the parallelogram effect of LMA on the diagonal through the apical vertebra.

BACKGROUND: There were several reports describing the biomechanics and microstructure of multifidus muscles in patients with lumbar disc herniation. However, correlations between lumbar multifidus muscle atrophy (LMA), spinopelvic parameters, and severity of adult degenerative scoliosis (ADS) have not been investigated. The study evaluated the impact of LMA and spinopelvic parameters on the severity of ADS. METHODS: One hundred and thirty-two patients with ADS were retrospectively reviewed. Standing whole-spine X-ray was used to evaluate the coronal (coronal Cobb angle, CA; coronal vertical axis, CVA) and sagittal (sagittal vertical axis, SVA; thoracic kyphosis, TK; lumbar lordosis, LL; pelvic incidence, PI; pelvic tilt, PT; sacral slope, SS) parameters. LMA was evaluated on axial T2-weighted magnetic resonance imaging (MRI) at intervertebral levels above and below the vertebra at the apex of the scoliotic curve. Clinical symptoms were evaluated by the Oswestry Disability Index (ODI) and the Japanese Orthopaedic Association (JOA) score. Multiple linear regression was used to assess correlations between LMA, spinopelvic parameters, and severity of scoliosis. RESULTS: LL and PT were negatively correlated with CA (P < 0.001); LL was positively correlated with SVA (P < 0.001). PI was positively correlated with CA (P < 0.001) and CVA (P < 0.001). PT (P < 0.001) and SS (P < 0.001) were negatively correlated with CVA. SS was negatively correlated with SVA (P < 0.001). Concave LMA at the upper or lower intervertebral level of the apical vertebra was positively correlated with CA (P ≤ 0.001); convex LMA at the upper or lower intervertebral level was negatively correlated with CA (P < 0.001). Convex LMA at the upper intervertebral level and concave LMA at the lower intervertebral level of the apical vertebra were negatively correlated with the SVA (P ≤ 0.001). At the upper intervertebral level, LMA on the concave side was positively correlated with CVA (P = 0.028); LMA on the convex side was negatively correlated with CVA (P = 0.012). PI was positively correlated with ODI (P < 0.001); PT (P < 0.001) and SS (P < 0.001) were negatively correlated with ODI. At the lower intervertebral level, LMA on the concave side was positively correlated with ODI (P = 0.038); LMA on the convex side was negatively correlated with ODI (P = 0.011). PI was positively correlated with JOA (P < 0.001); PT (P < 0.001) and SS (P < 0.001) were negatively correlated with JOA. CONCLUSIONS: Spinopelvic parameters are correlated with the severity of ADS. Asymmetric LMA at both upper and lower intervertebral levels of the apical vertebra is positively correlated with CA. LMA on the diagonal through the apical vertebra is very important to maintain sagittal imbalance via parallelogram effect. LMA at lower intervertebral levels of the apical vertebra may have a predictive effect on ODI. JOA score seems to be more correlated with spinopelvic parameters than LMA.

Comparison of the French and CARDS classifications for lumbar degenerative spondylolisthesis: reliability and validity.

BACKGROUND: The aim of this study was to compare the reliability and validity of the CARDS and French classification systems for lumbar DS. METHODS: Between May 2013 and December 2016, 158 consecutive patients diagnosed with single-level lumbar DS were included in this study, and all underwent lumbar fusion. All patients underwent long-cassette standing anterioposterior and lateral radiographs of the spine preoperatively and postoperatively. The images were graded according to the CARDS and French classification systems by two orthopedic spinal surgeons and two orthopedic spinal fellows, independently. Clinical outcome measures used were the visual analog scale, Oswestry Disability Index, and the 36-Item Short Form Health Survey. Clinical data were collected before surgery and 1 year after surgery. RESULTS: A total of 146 patients were finally included in this study and followed up for at least 1 year. When grading using the CARDS system, the κ values for inter- and intraobserver reliability were 0.837 and 0.869, respectively, representing perfect agreement. The interobserver κ value for the French classification was 0.693 and the intraobserver κ value was 0.743, both representing substantial agreement. CARDS Type D patients have higher preoperative back pain scores and better improvement after surgery compared with non-Type D patients. Mean back and leg pain was worse in French Type 5 patients, while the most significant improvement was also seen in Type 5 patients after surgery. CONCLUSIONS: Both CARDS and French classification systems have acceptable reliability and validity. The CARDS system is easier to utilize and has better reliability. LEVEL OF EVIDENCE: IV.

Factors associated with postoperative outcomes in patients with intramedullary Grade II ependymomas: A Systematic review and meta-analysis.

BACKGROUND: Most of the previous studies combined all types of intramedullary ependymomas without providing accurate pathological subtypes. In addition, it was very difficult to evaluate the factors associated with postoperative outcomes of patients with different pathological subtypes of intramedullary Grade II ependymomas by traditional meta-analysis. This study evaluated the factors related with postoperative outcomes of patients with intramedullary Grade II ependymomas. METHODS: Individual patient data analysis was performed using PubMed, Embase, and the Cochrane Central Register of Controlled Trials. The search included articles published up to April 2018 with no lower date limit on the search results. The topics were intramedullary Grade II ependymomas. Progression-free survival (PFS) and overall survival (OS) were analyzed by Kaplan-Meier survival analysis (log-rank test). The level of significance was set at P < .05. RESULTS: A total of 21 studies with 70 patients were included in this article. PFS of patients who underwent total resection was much longer than the PFS of those who received subtotal resection (P < .001). Patients who received adjuvant therapy (P = .005) or radiotherapy and chemotherapy (P < .001) seemed to have shorter PFS than others; PFS of patients who had cerebrospinal fluid disease dissemination (P = .022) or scoliosis (P = .001) were significantly shorter than others. OS of cellular ependymoma patients was less than giant cell ependymoma patients (P < .001). CONCLUSIONS: PFS of patients who received total resection was much longer than those who received subtotal resection. Patients treated with adjuvant therapy or radiotherapy and chemotherapy appeared to have shorter PFS than others; PFS of patients with cerebrospinal fluid disease dissemination or scoliosis were significantly shorter than others. Cellular ependymomas would have better OS than giant cell ependymoma. However, giant cell ependymoma patients might have the worst OS.

Complications in Elderly Patients Undergoing Lumbar Arthrodesis for Spinal Stenosis.

PURPOSE: To report the perioperative complication rates in elderly patients undergoing lumbar arthrodesis and to analyze the risk factors. METHODS: Between September 2015 and June 2018, 215 patients aged ≥70 underwent posterior lumbar arthrodesis with pedicle screw fixation. Demographic data including age, gender, smoking status, body mass index (BMI) and preoperative comorbidities were collected. Operative records as the number of levels fused, estimated blood loss, time of surgery, and the occurrence of perioperative complications were reviewed. Risk factors of perioperative complications were determined by logistic regression analysis. RESULTS: The total perioperative complication rate in all patients was 30.2%, of which major complications occurred in 24 patients (11.2%) and minor complications occurred in 41 patients (19.1%). Two risk factors of perioperative complications (major or minor) were chosen: BMI (cutoff value 24.32) and surgical level (≥3). Lower surgical level (≥3) and smaller BMI were risk factors for perioperative minor complications, and major complication was affected only by surgical level (≥3). CONCLUSIONS: The risk factor of perioperative complication in elderly patients after lumbar arthrodesis was fusion segment (≥3), and BMI was a protective factor. Elderly patients with BMI <24.32 are more likely to have perioperative complications after lumbar arthrodesis.

The Parallelogram Effect of Degenerative Structures Around the Apical Vertebra in Patients with Adult Degenerative Scoliosis: The Influence of Asymmetric Degeneration and Diagonal Degeneration on the Severity of Deformity.

BACKGROUND This is the first published study assessing the parallelogram effect of degenerative structures around the apical vertebra. We evaluated the effect of degenerative structures around the apical vertebra and spinopelvic parameters on the severity of ADS. MATERIAL AND METHODS We retrospectively reviewed data on 144 patients with ADS. The coronal (coronal Cobb angle, CA) and sagittal (thoracic kyphosis, TK; sagittal vertical axis, SVA; pelvic incidence, PI; lumbar lordosis, LL; sacral slope, SS; pelvic tilt, PT) parameters, lumbar multifidus muscle atrophy (LMA), and facet joint osteoarthritis (FJOA) were evaluated. Multiple linear regression was used to assess the correlations. RESULTS LL and PT were negatively correlated with CA (P<0.001), and the correlation between LL and SVA was positive (P<0.001), as was the correlation between PI and CA (P<0.001). The correlation between SS and SVA was negative (P<0.001). The correlation between CA and concave LMA at upper or lower intervertebral level of the apical vertebra was positive (P≤0.001). The convex LMA at upper and lower intervertebral levels was negatively correlated with CA (P<0.001). Convex LMA at the upper intervertebral level and concave LMA at the lower intervertebral level of the apical vertebra were negatively correlated with the SVA (P≤0.001). FJOA works similar to LMA (P<0.05). CONCLUSIONS Spinopelvic parameters are correlated with severity of ADS. The structures around the apical vertebra are very important to maintain global alignment of the spine via the parallelogram effect.

Influence of the Ratio of C2-C7 Cobb Angle to T1 Slope on Cervical Alignment After Laminoplasty.

PURPOSE: To assess the relationship between the ratio of C2-C7 Cobb angle to T1 slope (CL/T1S) and cervical alignment changes after laminoplasty. METHODS: 78 consecutive patients with cervical myelopathy who underwent laminoplasty were enrolled. All patients with preoperative and follow-up cervical spine lateral x-ray images available for review were recruited in this study. Imaging data included C2-C7 Cobb angle, T1 slope, and cervical sagittal vertical axis (cSVA). All patients were classified into low-ratio group (bottom 25% of CL/T1S), fair-ratio group (middle 50% of CL/T1S), and high ratio group (top 25% of CL/T1S) according to CL/T1S ratio. The recovery rate was calculated based on the Japanese Orthopedic Association score. RESULTS: The preoperative C2-C7 Cobb angle had significant correlations with the T1 slope (r = 0.528). Kyphotic alignment changes in the group with a high ratio of CL/T1S was greater than that of the other 2 groups (P < 0.001). The incidence of postoperative kyphosis in the group with a low ratio of CL/T1S was higher than that of the other 2 groups (P < 0.001). There was no postoperative kyphosis in the fair-ratio group. The surgical outcome in the low-ratio CL/T1S group and the high-ratio CL/T1S group was poorer than that in the fair-ratio CL/T1S group (P = 0.005). CONCLUSIONS: The cervical alignment was kept well in the mid-range CL/T1S ratio group after laminoplasty. Patients with a high CL/T1S ratio were more likely to present with kyphotic alignment changes. Patients with a low CL/T1S ratio were more likely to have postoperative kyphosis.

Perioperative Complications And Risk Factors In Degenerative Lumbar Scoliosis Surgery For Patients Older Than 70 Years Of Age.

STUDY DESIGN: Multivariate analysis of retrospective registry data. OBJECTIVE: To report the perioperative complication in a large cohort of surgery for elderly degenerative lumbar scoliosis (DLS) patients and to analyze the risk factors. SUMMARY OF BACKGROUND DATA: The perioperative complication rate and risk factors for patients with DLS remain unclear, especially in elderly population. METHODS: Between November 2015 and June 2018, 98 patients aged 70 or older with DLS received decompression and intervertebral fusion by one spine surgeon at Beijing Xuanwu Hospital. The medical history and comorbidities of all patients were recorded. RESULTS: The perioperative complication rate was 34.7% in all patients, 11.2% of all patients had major complications, and 31.6% had minor complications. The major complication most commonly seen was wound infection, and the most common minor complication was hypoproteinemia. Elderly patients (>75) had longer hospital stays (17.5 ± 7.9) when compared to younger patients. Two risk factors of perioperative complications were chosen after binary logistic regression analysis: lower BMI and longer instrumented segments. The only risk factor for major complications was longer instrumented level (≥3), and the only risk factor for minor complications was lower BMI. CONCLUSION: Our findings indicate that in elderly patients with DLS, lower BMI is a risk factor for minor perioperative complication. Obesity is not a major problem in this population, on the contrary, BMI is a protective factor for perioperative complications. The risk factors for major perioperative complications in elderly patients with DLS are longer instrumented segments but not related to the number of decompression and intervertebral fusion levels. Preoperative comorbidities and advanced age were not associated to a higher perioperative complication rate in elderly patients. The perioperative complication rate in patients with DLS over 70 years of age is found to be acceptable with appropriate perioperative management.

Clinical and magnetic resonance imaging predictors of the surgical outcomes of patients with cervical spondylotic myelopathy.

OBJECTIVE: To determine whether clinical characteristics and signal and morphologic changes on magnetic resonance (MR) images of the spinal cord (SC) are associated with surgical outcomes for cervical spondylotic myelopathy (CSM). PATIENTS AND METHODS: A total of 113 consecutive patients with cervical myelopathy underwent cervical decompression surgery in our hospital from January 2015 to January 2018. All patients with preoperative MR images available for review were recruited for this study. Research data included patient sex, age, duration of symptoms, surgical approach, compression level, preoperative mJOA (modified Japanese Orthopaedic Association) score, postoperative mJOA recovery rate, and complications. Imaging data included signal changes on T2-weighted MRI images (grade and extension on sagittal images, four types of signal changes on axial images according to the Ax-CCM system), SC compression, transverse area of the SC, and compression ratio. The t-test, Mann-Whitney U-test, Kruskal-Wallis H - test, analysis of variance, and regression analysis were used to evaluate the effects of individual predictors on surgical outcomes. RESULTS: The study cohort included 85 males and 27 females with a mean age of 60.92 ± 8.93 years. The mean mJOA score improved from 10.24 ± 1.69 preoperatively to 15.11 ± 2.05 at the final follow-up (p < 0.001). Patients in the poor outcome group were more likely to present with a longer duration of symptoms (p < 0.001) and smaller transverse area of the SC (p < 0.001). Bright T2-weighted high signal changes (T2HSCs), multisegmental high signal changes on sagittal MR images, and fuzzy focal T2HSCs on axial MR images were associated with a poor outcome (p < 0.001, p = 0.005, p < 0.001, respectively). The maximum SC compression and compression ratio were not reliable predictors of surgical outcomes (p = 0.375, p = 0.055, respectively). The result of multivariate stepwise logistic regression showed that a longer duration of symptoms, multisegmental T2HSCs on sagittal MR images and fuzzy focal T2HSCs on axial MR images were significant risk factors of poor outcomes (p < 0.001, p = 0.049, p = 0.016, respectively). CONCLUSION: A longer duration of symptom, multisegmental T2HSCs on sagittal MR images, and fuzzy focal T2HSCs on axial MR images were highly predictive of a poor surgical outcome for CSM. Smaller transverse area of the SC and bright T2HSCs were also associated with the prognosis of CSM.

Survival outcomes and prognostic factors of patients with intramedullary Grade II ependymomas after surgical treatments.

This study evaluated survival outcomes of patients with intramedullary Grade II ependymomas and identify prognostic factors. Electronic searches of PubMed, EMBASE, OVID, the Cochrane Central Register of Controlled Trials were performed to identify trials according to the Cochrane Collaboration guidelines. The objects were intramedullary Grade II ependymoma according to 2007 WHO classification. Kaplan-Meier survival analysis with log-rank test was used to analyze progressive free survival (PFS) and overall survival (OS). Cox proportional hazard model was utilized for multivariate analysis with hazard ratio (HR) and 95% confidence interval (CI) calculated. P values <0.05 were considered statistically significant. A total of 28 studies including 138 cases of intramedullary Grade II ependymomas were retrieved. Patients who were classified as cellular ependymomas or papillary ependymomas had higher risks of progression than those who possessed typical Grade II ependymomas. Patients who were treated with adjuvant therapy had a higher risk of progression than those without adjuvant therapy. OS of patients with giant cell ependymoma was significantly shorter than those with typical Grade II ependymoma. Patients who had cellular or papillary subtype, adjuvant therapy would have a shorter estimated value of progression-free time and a higher risk of progression than typical Grade II ependymomas. Giant cell ependymoma patients would have a higher risk of fatality than those with typical Grade II ependymomas. Definite pathology type and appropriate treatments were foundations of intramedullary Grade II ependymomas' managements.