Methods: From March 2020 to March 2023, 100 inpatients with DS were classified into groups A, B, C, and D based on the CARDS classification system. Preoperative radiological data were analyzed to measure the severity of central canal stenosis, facet joint arthropathy, intervertebral disc herniation, and spinal epidural lipomatosis, osteophyte formation, range of motion (ROM), and computed tomography value of the vertebral bodies. The radiological characteristics and clinical contraindications for OLIF were compared among the groups. Results: Of the 100 patients, 51% had clinical contraindications for OLIF, which included 85%, 25%, 62.5%, and 20% of patients in groups A, B, C, and D, respectively. Compared with group B, group A demonstrated greater severity of central canal stenosis, whereas group C showed a higher degree of facet joint arthropathy. More patients in groups A and C had severe central canal stenosis. Regarding the ROM results, group A had segmental stiffness, whereas group D presented relatively unstable slip segments. Conclusions Patients with different DS subtypes have varied radiological characteristics. Groups B and D are suitable candidates for OLIF. Most patients in group A are unsuitable for OLIF because of bony hyperplasia, severe spinal stenosis, and segmental stiffness.

Methods: From March 2020 to March 2023, 100 inpatients with DS were classified into groups A, B, C, and D based on the CARDS classification system. Preoperative radiological data were analyzed to measure the severity of central canal stenosis, facet joint arthropathy, intervertebral disc herniation, and spinal epidural lipomatosis, osteophyte formation, range of motion (ROM), and computed tomography value of the vertebral bodies. The radiological characteristics and clinical contraindications for OLIF were compared among the groups. Results: Of the 100 patients, 51% had clinical contraindications for OLIF, which included 85%, 25%, 62.5%, and 20% of patients in groups A, B, C, and D, respectively. Compared with group B, group A demonstrated greater severity of central canal stenosis, whereas group C showed a higher degree of facet joint arthropathy. More patients in groups A and C had severe central canal stenosis. Regarding the ROM results, group A had segmental stiffness, whereas group D presented relatively unstable slip segments. Conclusions Patients with different DS subtypes have varied radiological characteristics. Groups B and D are suitable candidates for OLIF. Most patients in group A are unsuitable for OLIF because of bony hyperplasia, severe spinal stenosis, and segmental stiffness.

Methods: From March 2020 to March 2023, 100 inpatients with DS were classified into groups A, B, C, and D based on the CARDS classification system. Preoperative radiological data were analyzed to measure the severity of central canal stenosis, facet joint arthropathy, intervertebral disc herniation, and spinal epidural lipomatosis, osteophyte formation, range of motion (ROM), and computed tomography value of the vertebral bodies. The radiological characteristics and clinical contraindications for OLIF were compared among the groups. Results: Of the 100 patients, 51% had clinical contraindications for OLIF, which included 85%, 25%, 62.5%, and 20% of patients in groups A, B, C, and D, respectively. Compared with group B, group A demonstrated greater severity of central canal stenosis, whereas group C showed a higher degree of facet joint arthropathy. More patients in groups A and C had severe central canal stenosis. Regarding the ROM results, group A had segmental stiffness, whereas group D presented relatively unstable slip segments. Conclusions Patients with different DS subtypes have varied radiological characteristics. Groups B and D are suitable candidates for OLIF. Most patients in group A are unsuitable for OLIF because of bony hyperplasia, severe spinal stenosis, and segmental stiffness.

Objective:To investigate the diagnostic efficacy of MRI-based or CT-based measurements and the combined evaluation methods for preoperative bone quality assessment in patients with cervical degenerative diseases.Methods:Patients who underwent spine surgery for cervical degenerative diseases at the Department of Orthopedics, Huashan Hospital, Fudan University from September 2020 to March 2022 with available preoperative X-ray, CT, MRI and dule energy X-Ray absorptiometry (DEXA) data were included in this study. Vertebral bone quality score (VBQ) based on MRI T1-weightedimages and CT Hounsfiled unit (HU) values of the cervical spine were measured, and a combined diagnostic formula based on the binary logistic regression was constructed. The patients were divided into normal bone mass (T≥-1.0) and osteopenia/osteoporosis groups (T<-1.0). The student's t-test and Chi-square test were performed for comparisons between groups. The Pearson correlation coefficient was also used to investigate the correlation between DEXA-T scores, cervical VBQ and CT HU values. In addition, receiver operating characteristic curve (ROC) were plotted to explore the diagnostic efficacy of VBQ, CT HU and their combined diagnosis. Meanwhile, the corresponding sensitivity and specificity were obtained. Results:A total of 71 patients were included in this study (17 in the normal group and 54 in the osteopenia/osteoporosis group). The student's t-test showed that VBQ (2.90±0.70 vs. 3.83±0.83, t=4.23, P<0.001) and CT HU values (370.26±85.38 vs. 295.20±67.96, t=3.73, P=0.002) were significantly different between the two groups. The area under the ROC curve (AUC) for VBQ and CT values of the cervical spine were 0.81 and 0.75, respectively, and the AUC for the combined diagnostic value constructed on the basis of both was 0.85. Applying VBQ scores alone had a diagnostic sensitivity of 80% and a specificity of 70%, and the combined diagnosis with VBQ and CT HU had a sensitivity of 90% and a specificity of 75%. Person correlation analysis showed a significant correlation between DEXA T value, cervical VBQ value and CT HU value. The detailed formula was: DEXA T score=-0.63×cervical VBQ+0.64 ( r=-0.55, P<0.001), CT HU value=-40.20×cervical VBQ+458.40 ( r=-0.45, P<0.001), DEXA T score=0.006×CT HU-3.47 ( r=0.45, P<0.001). Conclusion:This study confirmed the feasibility of using cervical VBQ values, CT HU values and combined diagnostics for preoperative bone density screening in patients with degenerative cervical spine diseases. This method allows surgeons to perform an initial preoperative bone density screening based on the patient's existing imaging data, and thus could aid in confirming the indication and scheme of surgery. The method could be a powerful tool for preoperative bone density assessment screening in patients with cervical degenerative diseases.

Objective:To investigate the correlation between paraspinal muscle atrophy, morphological changes of facet joints and adjacent segment disease (ASDis) after lumbar fusion operation.Methods:A retrospective study was conducted among 195 patients who underwent posterior lumbar fusion again for ASDis at this institution from January 2014 to December 2020, including 29 patients with ASDis whose initial surgical fusion segment was L 4,5. According to Roussouly's staging, there were 5 cases of type I, 9 cases of type II, 10 cases of type III, and 5 cases of type IV. Another 29 cases were selected from patients without ASDis after lumbar fusion as a control group. The control group was paired 1∶1 with the ASDis group according to gender, fusion segment, and Roussouly typing of the lumbar spine. The cross-sectional area (CSA) and fat infiltration (FI) of paravertebral muscle, facet joint angle (F-J) and pedicle facet (P-F) angle before the first (second) operation were measured and compared between the two groups. Then logistic regression analysis was used to determine the predictors of ASDis after posterior lumbar fusion. Finally, the receiver operation characteristic (ROC) curve was described, and the area under the curve (AUC) and cut-off point were calculated. At the same time, the paraspinal muscle atrophy before the second operation in ASDis group was measured. Results:The average follow-up time of 98 patients was 59.25±6.38 months (range, 49-73 months). The average body mass index (BMI) of ASDis group was 24.76±3.64 kg/m 2, which was higher than that in control group (22.24±2.92 kg/m 2) ( t=2.481, P=0.041). The average CSA and relative cross-sectional area (rCSA) of paraspinal muscle in ASDis group were 3 214.32± 421.15 mm 2 and 1.69±0.36 respectively, which were less than 3 978.91±459.87 mm 2 and 2.26±0.29 in control group ( t=10.22, P=0.012; t=9.47, P=0.038). The FI degree of paraspinal muscle in ASDis group (21.95%±5.89%) was significantly higher than that in control group (14.64%±7.11%) ( t=7.32, P=0.002). The F-J angle in ASDis group was 35.06°±3.45°, which was less than 38.39°±4.67° in control group ( t=4.76, P=0.027). The P-F angle in ASDis group was 117.39°±8.13°, which was greater than 111.32°±4.78° in control group ( t=5.25, P=0.031). Multivariate logistic regression analysis showed that higher BMI ( OR=1.34, P=0.038), smaller rCSA of paraspinal muscle ( OR=0.02, P=0.017) and higher FI of paraspinal muscle ( OR=1.58, P=0.032) were the risk factors of postoperative ASDis. The ROC curve showed that the AUC of BMI was 0.680 and the cut-off point was 22.58 kg/m 2; The AUC of the FI of paraspinal muscle was 0.716 and the cut-off point was 15.69%; The AUC of rCSA of paraspinal muscle was 0.227 and the cut-off point was 1.92. For ASDis patients, the paraspinal muscle before the second operation had a higher degree of FI (25.47%±6.59% vs. 21.95%±5.89%, t=3.99, P=0.042) and a smaller rCSA (1.52±0.28 vs. 1.69±0.36, t=3.85, P=0.038) than that before the first operation. The difference between the FI degree of paraspinal muscle before the second operation and the first operation was negatively correlated with the occurrence time of ASDis ( r=-0.53, P=0.039) , and the difference of rCSA was positively correlated with the occurrence time of ASDis ( r=0.64, P=0.043) . Conclusion:When BMI >22.58 kg/m 2, FI of paraspinal muscle >15.69%, and rCSA of paraspinal muscle <1.92, it suggests that ASDis is more likely to occur after operation. And the more obvious paraspinal muscle atrophy after the first operation, the earlier ASDis may occur. Morphological changes of facet joints cannot be used as an index to predict the occurrence of ASDis.

Objective:To investigate the influence of interbody cage height during oblique lumbar interbody fusion (OLIF) on lumbar biomechanics with different degrees of degeneration and to provide a reference for cage choice.Methods:The finite element model of normal lower lumbar spine (L 3-S 1) was built and validated, then constructed three different degenerative segments in L 3, 4, and the cages with different height (8, 10,12, 14 mm) were implanted into L 4, 5 disc. All the twelve models were loaded with pure moment of 7.5 N·m to produce flexion, extension, lateral bending and axial rotation motions on lumbar spine, and the effects of cage height on range of motion (ROM), intervertebral pressure in adjacent segments and stress in facet joints were investigated. Results:The ROM of adjacent segments and the maximum stress of intervertebral discs increased with the increase of cage height, but this trend was not obvious in moderate and severe degeneration groups. After implantation of 4 different height cages (8, 10, 12, 14 mm), the ROM of L 3, 4 segment reached the maximum during extension. The ROM of mild degeneration group was 2.68 °, 2.71 °, 2.94 °, 2.98 °, moderate degeneration group was 2.33°, 2.37°, 2.41°, 2.49°, and severe degeneration group was 1.94 °, 1.99 °, 2.14 °, 2.21 °. The stress of L 3, 4 intervertebral disc reached the maximum during right bending. The maximum stress of L 3, 4 intervertebral disc was 23.95 MPa, 24.60 MPa, 24.90 MPa and 25.34 MPa in mild group, 25.57 MPa, 25.60 MPa, 25.82 MPa and 25.89 MPa in moderate group, and 25.95 MPa, 25.99 MPa, 26.48 MPa and 27.13 MPa in severe group. The maximum stress of L 3, 4 facet joint was 15.87 MPa, 15.78 MPa, 16.29 MPa and 16.43 MPa in mild group, 15.97 MPa, 16.31 MPa, 16.53 MPa and 16.79 MPa in moderate group, and 16.17 MPa, 16.49 MPa, 16.95 MPa and 17.35 MPa in severe group. Conclusion:For patients with mild lumbar degeneration requiring OLIF surgery, the intervertebral height of the surgical segment should not be overstretched. But for patients with moderate to severe lumbar degenerative disease who need to undergo OLIF surgery, it is recommended that the cage height be 0-2 mm higher than the original intervertebral space height.

Fusion surgery has been an effective modality for the treatment of spinal disorders for more than 100 years. With the increasing understanding of the disease and the increasing maturity of surgical techniques, lumbar fusion has become more widely performed and its efficacy has been conclusively proven. However, fusion surgery inevitably disrupts the original physiologic motion of the spine and limits segmental motion, resulting in a significant increase in disc and joint protrusion stress in adjacent segments. When a newly identified degenerative change on imaging is present in an adjacent segment or an existing degeneration is more aggravated, this is known as adjacent segment degeneration. When clinical symptoms such as pain and numbness in the lower extremities are present that are consistent with degeneration, this is known as adjacent segment disease. Real world studies (RWS) have become a major focus in medical research in recent years. Since it is closer to clinical practice and more practical for decision-making compared with randomized controlled trail (RCT), it is gaining importance in clinical practice. By searching major national and international databases, this article provides a review of risk factors as well as advances in the treatment of lumbar adjacent segment disease in RWS. According to the retrieved literature, there are many factors that contribute to the development and progression of adjacent segment degeneration and disease, which are mainly divided into patient-related factors and surgery-related factors. In general, patient age, weight, spinal-pelvic sagittal parameters, and internal diseases influence the progression of adjacent segment degeneration. Surgery-related risk factors include the number of segments operated on, the surgical approach, interference with adjacent segments, and whether the spinal-pelvicsagittal imbalance is corrected. To prevent the development of adjacent segment disease, patients can slow the progression of adjacent segment degeneration by reducing their own weight and controlling their internal diseases. The physician can also avoid the influence of surgery-related factors through adequate surgical planning and careful intraoperative management. At the same time, surgeries may be performed in patients who have developed adjacent segmental disease and for whom conservative treatment has failed. The current revision surgical approaches include endoscopic simple decompression and posterior decompression with extended internal fixation.Short-term RWS revealed that the efficacy of endoscopic treatment of adjacent spondylosis might be equivalent to re-fusion internal fixation surgery. Studies with large samples and long-term follow-up are still needed to guide the treatment of adjacent segment disease in the future, in order to improve clinical decision-making.

Objective:To establish a radiological classification system for acute cervical spinal cord injury without fracture or dislocation in adults and evaluate its credibility.Methods:A retrospective case series study was performed to analyze the clinical and radiological data of 132 patients with acute cervical spinal cord injury without cervical fracture or dislocation admitted to Huashan Hospita，Fudan University from January 2010 to December 2018. There were 97 males and 35 females，aged 18-82 years［（57.4±17.8）years］. The radiological classification system of acute cervical spinal cord injury without fracture and dislocation in adults was established based on spinal cord compression and its compressors，and the disco-ligamentous complex（DLC）injury. The number，age and causes of injury of each subtype were further analyzed. Another 24 patients with acute cervical spinal cord injury without fracture and dislocation were collected and assessed to calculate the Kappa coefficient for credibility assessment in the radiological classification by orthopedic surgeons who did not participate in the establishment of the classification.Results:The radiological classification system of acute cervical spinal cord injury without fracture or dislocation in adults included types I-IV. Type I was the cervical spinal cord significantly compressed by the existed pathological factors such as the ossification of the posterior longitudinal ligament of the cervical spine and/or cervical spinal canal stenosis before the injury；Type II was the cervical spinal cord significantly compressed by traumatic disc herniation and/or epidural hematoma；Type III was the spinal cord without obvious compression，but with definite DLC injury；Type IV was the spinal cord without obvious compression，accompanied with no or only suspicious DLC injury. Type I and type II could be with or without DLC injury. Eighty-three patients（62.9%）were classified as type I，with the age of（62.2±15.7）years，and the main cause of injury was fall injury（37 patients，44.6%），followed by traffic injury（31 patients，37.3%）. Seventy patients（12.9%）were classified as type II，with the age of（55.8±13.4）years，and the traffic injury（9 patients，52.9%）and fall injury（5 patients，29.4%）were more common. Twenty-four patients（18.2%）were classified as type III，with the age of（53.6±16.3）years，and the main causes of injury were fall injury（9 patients，37.5%）and traffic injury（8 patients，33.3%）. Eight patients（6.1%）were classified as type IV，with the age of（37.4±11.6）years，and the main causes of injury were traffic injury（4 patients，50.0%）and sports injury（3 patients，37.5%）. The credibility assessment of the radiological classification of acute cervical spinal cord injury without fracture or dislocation in adults showed that the consistency percentage was 79.2%-87.5%（mean，81.2%）among different observers. The Kappa coefficient was 0.691-0.866（mean，0.789），and the credibility was basically credible（0.61-0.80）.Conclusions:The established radiological classification system of acute cervical spinal cord injury without fracture or dislocation in adults has a good degree of credibility. Variances in age and causes of injury of each type suggest a good guidance value for clinical classification of acute cervical spinal cord injury without fracture and dislocation in adults.

Objective:To investigate the operational impact of the curve laterality of degenerative lumbar scoliosis on oblique lateral lumbar interbody fusion (OLIF).Methods:Data of 40 cases with degenerative lumbar scoliosis and 20 cases without degenerative lumbar scoliosis treated in our hospital from January to December 2017 were retrospectively analyzed. There were 20 cases in left convex group (male 5, female 15, 70.62±5.45 years old) and 20 cases in left concave group (male 3, female 17, 69.73±7.24 years old), and there were 20 cases of lumbar degenerative diseases without scoliosis (lumbar spinal stenosis 13 cases, lumbar disc herniation 7 cases; male 5, female 15, 71.48±5.73 years old). The following OLIF operation-related anatomical parameters were measured on MR axial T2 weighted image and lumbar spine X-ray image: distance from the left edge of the abdominal aorta to the anterior medial edge of the left psoas muscle; distance from the left edge of the abdominal aorta to the left lumbar sympathetic trunk; distance from the anterior medial edge of the left psoas muscle to the transverse axis of the vertebral body; distance between the midpoints of adjacent vertebral bodies in L 2-5; angle of rotation of the vertebral body and angle of the OLIF operating channel. One-way analysis of variance(ANOVA) and least significant difference (LSD) were used for statistical analysis of measurement parameters of different groups. Results:There were statistically significant differences between the distance from the left edge of the abdominal aorta to the anterior medial edge of the left psoas muscle, and the distance from the left edge of the abdominal aorta to the left lumbar sympathetic trunk in the three groups of cases (All P<0.05). The L 2, 3 segment (24.41±9.54 mm, 18.18±7.1 mm) and L 3, 4 segment (18.54±7.94 mm, 13.73±6.73 mm) in the left concave group were significantly larger than those in the no scoliosis group; and the above values of the L 4, 5 segment of the left convex group (19.16±7.04 mm, 11.67±3.63 mm) were significantly larger than those in the no scoliosis group. For the distance from the anterior medial edge of the left psoas muscle to the transverse axis of the vertebral body, the values of L 2, 3 and L 3, 4 (13.76±2.98 mm, 15.87±3.53 mm) in the left convex group were significantly greater than those in the no scoliosis control group; but in the left concave group, the corresponding values (9.97±3.14 mm, 10.75±5.03 mm) were significantly smaller than those in the no scoliosis group. The distances between the midpoints of adjacent vertebral bodies of L 2, 3 and L 3, 4 (37.67±3.45 mm, 38.18±3.54 mm) in the left convex group were greater than those in the no scoliosis group and left concave group, and the differences between the three groups were statistically significant ( P<0.05). Pearson correlation analysis between the absolute value of vertebral rotation angle and OLIF surgical passage angle showed that there was a negative correlation between them in the left convex group and a positive correlation in the left concave group. Conclusion:The curve laterality of degenerative lumbar scoliosis had a certain influence on the anatomical parameters of oblique lateral lumbar interbody fusion. It was recommended to design and adjust the operation skills according to the curve laterality before surgery.

This corrects the article “Analysis of Tau Protein Expression in Predicting Pathological Complete Response to Neoadjuvant Chemotherapy in Different Molecular Subtypes of Breast Cancer” in volume 23 on page 47.This article was initially published on the Journal of Breast Cancer with a misspelled the abbreviation in figure 3. The abbreviation ‘HP’ should be corrected as ‘HR’.