Objective To examine the expression of CD9 protein in pancreatic cancer tissues and adjacent tissues,and to analyze its relation with the progress and prognosis of pancreatic cancer.Methods From September 2005 to December 2009,surgical resected cancer tissues and adjacent tissues of 90 patients with pancreatic cancer and their clinical data were collected.The expression of CD9 protein in pancreatic cancer tissues and adjacent tissues was detected by immunohistochemistry,and its relationship with clinicopathological features was analyzed.Chi-square test was performed for comparison of ratios between groups.Overall survival (OS) analysis of 90 patients after surgery was performed.Results The high expression rate of CD9 protein (64.4％,58/90) in cancer tissue was significantly higher than that in cancer adjacent tissue (45.6％,41/90),the difference has statistically significant (χ2 =6.847,P＜0.05).CD9 protein was highly expressed in most of pancreatic cancer tissue which was well differentiated or without lymph node metastasis (74.6％ (50/67) vs 39.1％ (9/23),χz =9.554,P＜0.01; 50.0％(17/34) vs 73.2％(41/56),χ2 =5.856,P＜0.05 respectively).However,the expression of CD9 was not correlated with gender and age (both P＞0.05).OS and progression-free survival (PFS) of the patients with CD9 highly expressed were significantly longer than those with low expression of CD9 (median OS:33.0 months vs 7.0 months,χ2 =15.400 P＜0.01.Median PFS:30.5 months vs 5.0 months,χ2 =13.750,P＜0.01).Conclusion CD9 protein is a kind of protein related with the invasive ability of pancreatic cancer,which may play a role in progression and metastasis of pancreatic cancer and can help to determine the prognosis to a certain extent.

Objective To investigate the short-term clinical efficacy of Jack vertebral dilator kyphoplasty bone grafting combined with minimally invasive fixation in the treatment of thoracolumbar fracture.Methods A retrospective case series analysis was made on 34 patients with thoracolumbar fracture treated by minimally invasive transpedicular bone grafting and fixation in the injury vertebrae with Jack vertebral dilator from December 2014 to December 2015.There were 20 males and 14 females,and their age was 25-27 years (mean,46.7 years).According to the AO classification,there were 16 cases of type A1 and 18 type A3.The injured levels were at T11 in one case,at T12 in 6,at L1 in 15,at L2 in 9 and at L3 in 3.The operation time,blood loss,fluoroscopy frequency,incision length,and postoperative hospital stay duration were recorded.The visual analogue scale (VAS),Oswestry disability index (ODI),height ratio of vertebrae,Cobb angle,and complications were evaluated at follow-up.Results The operation time was (91.2 ±9.8) minutes,blood loss was (42.4 ±4.3) ml,incision length was (7.2 ± 0.4) cm,intraoperative fluoroscopy frequency were five,postoperative hospital stay was (3.9 ± 0.5) days,and follow-up time was (13.8 ± 1.7) months.All the patients showed complete healing in the injury vertebra.The VAS was (6.4 ± 0.9) points preoperatively,(4.1 ± 0.8) points,(1.2 ± 0.4) points,and (1.2 ± 0.5) points at 7 days,3 months and 12 months postoperatively.The ODI was (39.2 ± 2.3) points preoperatively,(24.5 ± 1.9) points,(13.0 ± 3.0) points,and (12.3 ± 2.0) points at 7 days,3 months and 12 months postoperatively.At postoperative 7 days,the VAS and ODI were significantly decreased compared with those preoperatively (P ＜ 0.05) and further declined at postoperative 3 months (P ＜ 0.05),while there was no significant difference between 3 months and 12 months postoperatively (P ＞ 0.05).The height ratio of vertebrae was 47.8 ± 12.2 preoperatively,83.6 ±4.9,82.5 ±4.8,and 81.7 ±4.7 at 7 days,3 months and 12 months postoperatively.The Cobb angle was respective (22.4 ± 4.7) °preoperatively,(3.6 ± 2.4) °,(4.6 ± 2.6) °,and (5.0 ± 2.8) ° at 7 days,3 months and 12 months postoperatively.At postoperative 7 days,the height ratio of vertebrae was increased and Cobb angle was decreased significantly compared to those preoperatively (P ＜ 0.05),while there was no significant difference in the indicators at 3 days,3 months and 12 months postoperatively (P ＞ 0.05).No looseness or breakage of internal fixation was found at follow-up and all patients had fracture union at the last follow-up.Conclusion Jack vertebral dilator kyphoplasty bone grafting combined with minimally invasive fixation is safe and effective for treatment of thoracolumbar fractures,as the procedure can quickly relieve the pain,improve the function disability,effectively maintain the height of the vertebral body and restore the sagittal balance of spine.

Objective To compare the clinical outcomes of dilator-kyphoplasty (DKP) and balloonkyphoplasty (BKP) in treatment of osteoporotic vertebral compression fractures. Methods From May 2007 to March 2009, 23 cases with 26 vertebrae were treated with DKP, while 29 cases with 29 vertebrae were treated with BKP procedures. The operating time, bleeding volume and injecting volume of cement were recorded during operation. The distribution of cement, the restoration of vertebral height and Cobb angle were observed. The patients' visual analogue scales (VAS) score and Oswestry disability index (ODI) score were evaluated after operation. Results There were no differences in operative time, bleeding volume of every vertebrae and cement injected volume between these two groups (P＞0.05). The vertebral height, Cobb angle, VAS and ODI scores were significantly improved than those of pre-operation in these two groups (P＜0.05). The height of the anterior vertebrae and Cobb angle in DKP groups were restored significantly than those in BKP groups (P＜ 0.05). There were 1 case (1 vertebra, 3.8%) underwent cement leakage in DKP groups and 5 cases (5 vertebrae, 17.2%) in BKP groups. Conclusion DKP and BKP were effective in the treatment of osteoporotic vertebral compression fractures. The height of the anterior vertebrae and Cobb angle in DKP groups were restored significantly than those in BKP groups.

Objective:To compare Jack dilator-kyphoplasty (DKP) and balloon-kyphoplasty (BKP) for osteoporotic vertebral compression fracture (OVCF) in postoperative vertebral height loss and adjacent intervertebral disc degeneration.Methods:A total of 94 OVCF patients were treated and fully followed up at Department of Orthopaedic Surgery, The First Hospital Affiliated to Nanjing Medical University from May 2007 to October 2016. Of them, 30 were subjected to DKP and 64 to BKP. In DKP group, there were 18 males and 12 females, with an age of (72.4±9.2) years, a bone density of (-3.99±0.88) SD and a disease course of (0.7±0.4) months; in BKP group, there were 28 males and 36 females, with an age of (71.6±14.3) years, a bone density of (-4.08±0.63) SD and a disease course of (0.6±0.3) months. The 2 groups were compared in terms of change in the height of injured vertebrae, disc height index percentage (DHIP) and Pfirrmann grading of adjacent disc degeneration at preoperation, 2 days and 36 months after operation.Results:The 2 groups were comparable due to insignificant differences in their preoperative general data ( P>0.05). The anterior and middle heights of injured vertebrae and DHIP at postoperative 36 months were significantly lower than those at postoperative 2 days in both groups ( P<0.05). There was no significant difference between the 2 groups in DHIP at 36 months after operation (79.86%±4.48% versus 80.24%±6.85%) ( t=0.277, P=0.782). By the Pfirrmann grading, 36 and 84 patients had intervertebral disc degeneration in DKP and BKP groups respectively. There was no significant difference in the incidence of intervertebral disc degeneration between the 2 groups (60.0% versus 65.6%) (χ 2=0.560, P=0.454). Conclusions:In the OVCF treatment, DKP and BKP may potentially cause height loss of the injured vertebrae and degeneration of adjacent intervertebral disc, but no difference was found in disc degeneration between the 2 modes.

Spinal cord injury leads to extremely high mortality and disability rates and its treatment has always been a global challenge. The survival of patients with spinal cord injury is partially lengthened with the development of medical treatments, but the clinical outcome is still not satisfactory. Some important progress has been made in the basic researches over spinal cord injury, such as analysis of repair mechanism of spinal cord injury and development of cellular therapies and biological scaffolds of spinal cord injury in China. However, some basic researches show insufficient understanding of the microenvironment and animal model of spinal cord injury and lack support from clinical problems, leading to too simplistic or contradictory conclusions. There is an urgent need to reexamine the research methods and carry out basic and clinical translational researches. Therefore, the authors discuss the key problems and difficulties in basic researches over spinal cord injury and propose improvement suggestions, aiming to provide a reference for conducting basic researches correctly and accelerating clinical innovational transformation.

Spinal cord injury is a common clinical disease secondary to spinal cord fractures that causes patients with motor and sensory dysfunction or even paralysis. In recent years, exosomes have participated in the occurrence and development of various diseases as nanometer-sized cell particles, and have received extensive attention. Exosomes derived from spinal cord tissue cells during spinal cord injury affect the injury process and tissue repair. In addition, exosomes as a new treatment for spinal cord injury have been widely studied. The authors document the mechanisms of various exosomes from spinal cord tissue and the repair effects of various cell-derived exosomes in spinal cord injury, in order to deepen the understanding of the role of exosomes in spinal cord injury and provide new ideas for studying the course and treatment of spinal cord injury.

Objective:To evaluate the accuracy and safety of cervical pedicle screw (CPS) placement under orthopaedic robot navigation system guidance.Methods:From March 2019 to February 2021, the data of 33 patients (19 males and 14 females, aged from 26 to 75 years, with an average age of 50.5 years) treated with pedicle screw fixation with the assistance of orthopaedic surgery robot through the posterior cervical spine were retrospectively analyzed. In clinical diagnosis, there was upper cervical fracture with instability in 14 patients (fracture nonunion in 2 patients), upper & subaxial cervical fracture in 1 patient, cervical spinal cord injury with spinal stenosis in 2 patients, cervical spinal stenosis in 9 patients, occipitocervical deformity in 2 patients, post-operative revision of cervical spondylosis in 2 patients, cervical intraspinal tumor in 3 patients. A total of 151 CPSs were inserted in C 1-C 7 using robot navigation system based on intraoperative three-dimensional C-arm fluoroscopy to assist in screw placement in posterior cervical surgery. Among them, 74 screws were implanted into upper cervical spine; 77 screws were implanted in the lower cervical spine. CT was used to obtain image data within 7 days after operation, and Neo classification was used to evaluate the accuracy of cervical pedicle screw placement. The patients were followed up for 2 weeks to observe the clinical symptoms and signs, and to determine whether there were surgical complications such as nerve and blood vessel injury and incision infection. Results:According to Neo classification, 91.4% (138/151) screws were completely contained in the pedicle without breaking through the pedicle cortex (grade 0). Among them, the accuracy of C 1 screws was 97.1% (34/35), C 2 screws was 92.3% (36/39), C 3 screws was 88.2% (15/17), C 4 screws was 71.4% (10/14), C 5 screws was 85.7% (12/14), C 6 screws was 93.3% (14/15), C 7 screws was 100.0% (17/17). The screw accuracy was highest in C 7, the lowest in C 4. The Kruskal-Wallis H test was performed on the accuracy of screw placement in different cervical level, and the results showed that there was no statistical difference (χ 2=1.31, P=0.971). However, a total of 13 screws were found to perforate the cortex of pedicle, although any neural or vascular complications associated with CPS placement were not encountered. Among them, 9 screws were found to perforate laterally, and 4 screws were found to perforate medially. No postoperative incision infection occurred in all cases. Conclusion:The safety of CPS placement can be effectively guaranteed with the assistance of the orthopaedic robot system.

Objective:To screen plasma exosomal protein molecular markers in patients with spinal cord injury (SCI) by applying Label-Free quantification and bioinformatics analysis.Methods:Fifty plasma specimens from the First Affiliated Hospital of Nanjing Medical University (from January 2021 to June 2022) were collected from SCI patients and healthy people, respectively. Plasma exosomes were isolated using ultracentrifugation and identified by transmission electron microscopy, nanoparticle tracking analysis and western blot. Plasma exosomal differentially expressed proteins (DEPs) were analyzed using Label-Free quantitative proteomics, and DEPs were characterized, annotated, and enriched based on Gene Ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) databases. The screened DEPs were validated by western blot and enzyme linked immunosorbent assay (ELISA) using plasma exosomal specimens.Results:According to the spinal cord injury classification of the American Spinal Injury Association, 14 cases were grade A, 19 cases were grade B, 12 cases were grade C, and 5 cases were grade D. Plasma exosomes of SCI patients and control groups showed typical cup-like morphology, with diameters mainly ranging from 30-200 nm. A total of 493 exosomal proteins were identified by Label-Free quantification, and 126 proteins were screened for differential expression, of which 38 were up-regulated and 88 were down-regulated. GO annotation revealed that DEPs were mainly involved in functions such as protein activation cascade, complement activation and immune response. KEGG pathway analysis revealed that DEPs were involved in biological pathways such as complement and coagulation cascade reactions, proteasome and neurodegenerative disease pathways. Two candidate proteins, APOB and S100A9, were initially screened based on quantitative results from proteomics and bioinformatics analyses. Western blot results showed that the relative expression of S100A9 protein in plasma exosomes of 30 SCI patients (1.62±0.19) was elevated compared with that of 30 control groups (0.86±0.24), and the difference was statistically significant ( t=8.55, P<0.001), while the relative expression of APOB protein (1.06±0.13 and 1.02±0.23) were not statistically significant ( t=0.46, P=0.653). The results of ELISA analysis showed that the expression of S100A9 in plasma exosomes of patients with different degrees of SCI (grade A 197.7±11.7 pg/ml, grade B 151.7±15.2 pg/ml, grade C 136.3±14.7 pg/ml) had statistical significance ( F=69.94, P<0.001), the higher the severity of SCI, the higher the expression of S100A9 in plasma exosomes (A vs. B, q=13.11, P<0.001; A vs. C, q=15.66, P<0.001; B vs. C, q=4.19, P=0.005). Conclusion:S100A9 is a potentially valid plasma exosomal molecular marker for assessing the severity of SCI.

Osteoporotic thoracolumbar fracture in the elderly will seriously reduce their quality of life and life expectancy. For osteoporotic thoracolumbar fracture in the elderly, spinal reconstruction is necessary, which should comprehensively consider factors such as the physical condition, fracture type, clinical characteristics and osteoporosis degree. While there lacks relevant clinical norms or guidelines on selection of spinal reconstruction strategies. In order to standardize the concept of spinal reconstruction for osteoporotic thoracolumbar fracture in the elderly, based on the principles of scientificity, practicality and progressiveness, the authors formulated the Clinical guideline for spinal reconstruction of osteoporotic thoracolumbar fracture in elderly patients ( version 2022), in which suggestions based on evidence of evidence-based medicine were put forward upon 10 important issues related to the fracture classification, non-operative treatment strategies and surgical treatment strategies in spinal reconstruction after osteoporosis thoracolumbar fracture in the elderly, hoping to provide a reference for clinical treatment.

Bone defects caused by different causes such as trauma, severe bone infection and other factors are common in clinic and difficult to treat. Usually, bone substitutes are required for repair. Current bone grafting materials used clinically include autologous bones, allogeneic bones, xenografts, and synthetic materials, etc. Other than autologous bones, the major hurdles of rest bone grafts have various degrees of poor biological activity and lack of active ingredients to provide osteogenic impetus. Bone marrow contains various components such as stem cells and bioactive factors, which are contributive to osteogenesis. In response, the technique of bone marrow enrichment, based on the efficient utilization of components within bone marrow, has been risen, aiming to extract osteogenic cells and factors from bone marrow of patients and incorporate them into 3D scaffolds for fabricating bone grafts with high osteoinductivity. However, the scientific guidance and application specification are lacked with regard to the clinical scope, approach, safety and effectiveness. In this context, under the organization of Chinese Orthopedic Association, the Expert consensus for the clinical application of autologous bone marrow enrichment technique for bone repair ( version 2023) is formulated based on the evidence-based medicine. The consensus covers the topics of the characteristics, range of application, safety and application notes of the technique of autologous bone marrow enrichment and proposes corresponding recommendations, hoping to provide better guidance for clinical practice of the technique.