Objective:To investigate the clinical significance of a new classification system for atlas fractures based on pre- and post-treatment CT features, with a focus on diagnosis and treatment.Methods:A retrospective analysis was conducted on 75 cases of cervical vertebra fractures treated at the Sixth Hospital of Ningbo City between January 2015 and December 2020. The study included 44 males and 31 females, with an average age of 53.3±13.0 years (range: 27-81 years). The fractures were classified according to the Landells classification, resulting in 12 cases of type I, 13 cases of type II, 33 cases of type III, 9 cases that were difficult to classify due to fracture lines located at anatomical junctions, and 8 cases that could not be classified using the Landells classification due to diverse injury mechanisms. To establish a new preliminary classification for cervical vertebra fractures, the researchers considered whether the fracture line in the CT images involved the facet joint surface of the atlas, the impact on bilateral half-rings, and the displacement distance of the fracture ends. Five spinal surgeons were randomly selected to classify the CT images of the 75 patients using the new classification method. After one month, the imaging data of the 75 cases of cervical vertebra fractures were randomized and reclassified to assess the reliability and repeatability of the classification.Results:The new cervical vertebra fracture classification method comprised three types based on whether the fracture line involved the facet joint surface of the atlas: type A (no involvement of the facet joint surface of the atlas), type B (involvement of one side of the facet joint surface with intact contralateral half-ring), and type C (involvement of one side of the facet joint surface with fractured contralateral half-ring). Additionally, based on the maximum displacement distance between the fracture ends (>4 mm), six subtypes were identified: subtype 1 (≤4 mm displacement) and subtype 2 (>4 mm displacement). Consequently, the subtypes were classified as A1, A2, B1, B2, C1, and C2. According to the new classification method, the 75 patients included 17 cases of A1, 12 cases of A2, 7 cases of B1, 13 cases of B2, 12 cases of C1, and 14 cases of C2. The classification demonstrated excellent consistency, as assessed by the five doctors, with Kappa values of 0.85 and 0.91 for reliability and repeatability, respectively. At the final follow-up, all conservatively treated patients achieved bone healing, while four surgically treated patients experienced non-union of the fracture ends but exhibited good fusion between the atlas and axis. The remaining surgically treated patients achieved bony union without complications such as loosening or fracture of internal fixation.Conclusion:The new cervical vertebra fracture classification method, based on CT imaging features, comprehensively covers common clinical cases of cervical vertebra fractures and demonstrates excellent consistency. It provides valuable clinical guidance for the diagnosis and treatment of cervical vertebra fractures.

Objective:To verify the prognostic significance of the tumor regression grade (TRG) for muscle-invasive bladder cancer (MIBC) patients undergoing radical cystectomy (RC) after neoadjuvant chemotherapy.Methods:The data of 70 MIBC patients treated with gemcitabine combined with cisplatin neoadjuvant chemotherapy and RC in Sun Yat-sen University Cancer Center between July 2016 to November 2021 were retrospectively reviewed. There were 65 males and 5 females, with an average age(59.79±10.56)years old. The patients accepted transurethral resection of bladder tumor (TURBT) specimens before neoadjuvant chemotherapy. Clinicopathological characteristics of patients were recorded and TRG was assessed. TRG evaluation criteria: TRG 1 was defined as no cancer residue, TRG 2 was defined as the proportion of residual cancer area to tumor bed area <50%, and TRG 3 was defined as the proportion of residual cancer area to the area of the tumor bed ≥ 50%. Chi-square test or Fisher's exact test were used to compare the relationship between patients' clinicopathological characteristics and TRG. The relationship between post-neoadjuvant therapy tumor and node(ypTN)stage, and survival, including overall survival(OS)and recurrence-free survival (RFS) were analyzed by Kaplan-Meier analysis. The pathologically locally descending disease was defined as (ypT < T 2 and ypN=N 0) and pathologically locally advanced disease was defined as (ypT≥T 2 and/or ypN ≥N 1). Cox regression was used for univariate and multivariate analysis of OS and RFS. Results:Chi-square test or Fisher exact test analysis showed TRG was significantly associated with ypT stage ( P < 0.001), ypN stage ( P = 0.002), lympho-vascular invasion ( P<0.001) and variant histology ( P<0.001). The OS of patients with TRG 1, TRG 2 and TRG 3 were 20.5(10.3, 31.8), 17.0(11.0, 30.8)and 15.0(11.0, 26.0) months, respectively, and the difference was significantly different( P = 0.037). The RFS of patients with TRG 1, TRG 2 and TRG 3 were 15.0(8.3, 25.5), 15.0(8.0, 27.0)and 11.0(4.5, 25.5) months, respectively, and the difference was significantly different ( P=0.029). There were significant differences between patients with pathologically locally descending disease and locally advanced disease in OS [18.5(10.3, 30.8)vs.15.0(11.0, 27.3)months, P = 0.013] and RFS [14.0(8.0, 24.0)vs. 11.5(8.0, 26.8)months, P = 0.012]. Among patients with locally advanced pathology, the OS was 19.5(11.0, 32.5)months for patients with TRG ≤2, 13.5(10.8, 26.0)months for patients with TRG 3( P=0.140). The RFS was 12.0(8.0, 31.0)months for those patients with TRG ≤2 and 11.0(6.0, 26.0)months for those patients with TRG 3( P = 0.180). Cox univariate analyses showed that patients with TRG 3 were associated with decreased OS ( HR = 6.043, 95% CI 1.170-31.213, P = 0.032) and RFS ( HR = 6.354, 95% CI 1.231-31.802, P = 0.027). Conclusions:This study showed that TRG was correlated with OS and RFS among patients. The patients who had the higher TRG had the worse prognosis. It was confirmed that TRG predicted the prognosis of patients undergoing radical cystectomy after neoadjuvant chemotherapy. Therefore, TRG assessment is recommend in pathology report for patients who had radical cystectomy after neoadjuvant chemotherapy.

Objective: This study aims to evaluate the efficacy of specific exercise therapy for the treatment of skeletally immature idiopathic scoliosis (IS). Methods: A total of 51 mild IS patients receiving specific exercise therapy in Guangdong Xinmiao Scoliosis Prevention Center from October 2017 to September 2021 were recruited in this study. Treatment outcome were evaluated at 1 year follow up. All the participants were divided into two groups: open ( n =32) and closed triradiate cartilage group ( n =19), and outcome of treatment were compared within the two groups. Results: After (26.5±9.8) months of treatment, the Cobb angle of the major curve was corrected from an average of (15.5±4.2)° to (11.3±6.7)°, with an average correction of (4.5±5.7)°. Among them, 58.9% patients achieved improvement in the major curve Cobb angle, 33.3% achieved stabilization, and 7.8% progressed. There was no significant difference in the major curve Cobb angle between the closed and open triradiate cartilage groups before treatment( t =-0.73, P =0.47), whereas there was a significant difference in the correction of the major curve after treatment( t =-2.73 , P <0.05). Conclusion Specific exercise therapy effectively prevents the progression or corrects the scoliosis in patients with skeletally immature idiopathic scoliosis. It s more effective in patients with open triradiate cartilage than in those with closed triradiate cartilage.

The emergence of regular short repetitive palindromic sequence clusters (CRISPR) and CRISPR- associated proteins 9 (Cas9) gene editing technology has greatly promoted the wide application of genetically modified pigs. Efficient single guide RNA (sgRNA) is the key to the success of gene editing using CRISPR/Cas9 technology. For large animals with a long reproductive cycle, such as pigs, it is necessary to screen out efficient sgRNA
Animals ; CRISPR-Cas Systems/genetics* ; Clustered Regularly Interspaced Short Palindromic Repeats/genetics* ; Gene Editing ; RNA, Guide/genetics* ; Swine

Objective:To explore the difference in properties of anterior occipital condyle plate screws compared with common anterior occipitalcervical fusion internal fixation.Methods:A 28-year-old healthy adult male volunteer's CT data of the occiput and neck was selected to establish finite element models：including the normal model，simple artificial vertebral fixation model（special-shaped titanium cage+clival screws），anterior occipital condyle plate and screw fixation model，and clival plate and screw fixation model，then a 50 N gravity and a torque of 1.5 N m were exerted upon the upper surface of the occipital bone to make the model produce flexion and extension，lateral bending and rotation. The motion range，internal fixation stress distribution and occipital bone stress distribution of each model under varying conditions were compared.Results:Under the conditions of flexion，extension，lateral bending and rotation，the range of motion of the normal model was 18.65°，15.35°，9.82° and 34.68°，respectively；that of the simple artificial vertebral fixation model was 3.20°，3.63°，2.94° and 3.92°，respectively；that of the clival plate and screw fixation model was 0.40°，0.50°，0.35° and 0.89°，respectively；that of the anterior occipital condylar plate and screw fixation model was 0.27°，0.33°，0.13° and 0.30°，respectively. Compared with the simple artificial vertebral fixation model，the range of motion of the clival plate and screw fixation model decreased by 87.5%，86.2%，88.1% and 77.3% in flexion，extension，lateral bending and rotation. The range of motion of the anterior occipital condylar plate and screw fixation model decreased by 91.5%，90.1%，95.6% and 92.3%，respectively. Under the conditions of flexion and extension，lateral bending and rotation，the stress peak of the simple artificial vertebral fixation model was 52.3 MPa，51.9 MPa，52.6 MPa，respectively；that of the clival plate and screw fixation was 100.1 MPa，158.1 MPa，170.6 MPa，respectively；that of the anterior occipital condylar plate and screw fixation was 114.2 MPa，62.9 MPa，132.9 MPa，respectively. Under the condition of flexion and extension，lateral bending and rotation，the stress peak of the occipital bone in the simple artificial vertebral body internal fixation model was 52.9 MPa，50.9 MPa and 62.3 MPa，respectively；that of the clival plate and screw fixation model was 19.7 MPa，55.9 MPa and 38.3 MPa，respectively；that of the anterior occipital condylar plate and screw fixation model was 37.8 MPa，15.0 MPa and 16.3 MPa，respectively. The stress in bone near the hypoglossal canal was close to 0 MPa，much smaller than the stress peak in occipital bone.Conclusion:Anterior occipital condylar plate and screw fixation in front of the special-shaped titanium cage can improve the stability of occipitocervical fusion with little effect on the occipital bone and hypoglossal canal or without obvious stress concentration，and hence is a safe and reliable anterior fixation method for upper cervical spine instability.

Objective:To investigate the safety of posterior atlantoaxial transarticular screw combined with atlas pedicle screw fixation in Chinese.Methods:CT data of upper cervical spine in 48 patients were collected from Ningbo No.6 Hospital, including 26 males and 22 females aged 26-58 years [(37.3±13.5)years]. All CT data was transformed into 3D dimensional model and inserted with virtual screws by Mimics 19.0. Firstly, the vertical plane P 1 and the horizontal plane P 2 of the atlas were built in those atlantoaxial models, secondly the atlantoaxial transarticular screw S 0 was inserted by Margel method, and it's insertion point was located at 3 mm lateral and 2 mm cephalad in the C 2 inferior articular process. Finally, four atlas pedicle screws were inserted at the midline of atlas lateral mass. The four screws are inserted as follows. S 1: the screw was tangent to the lateral side of the S 0 or the medial of the atlas pedicle. S 2: the screw was tangent to the lateral wall of the atlas pedicle. S 3: the screw was tangent to the upper wall of the atlas pedicle. S 4: the screw was tangent to the inferior wall of the atlas pedicle. The angles between S 1, S 2 and P 1 as the camber angle, and the angle between S 3, S 4 and P 2 as the gantry angle were measured. Then the safety range of camber angle and gantry angle were calculated, and the screw length of S 1, S 2, S 3 and S 4 was measured. In all models, the camber angle and gantry angle of the screws were adjusted an interval of 2°, the number of successful cases was calculated and the success rate of insertion was calculated. Results:All 3D models were inserted successfully. The minimum value, maximum value and safety range of the camber angle of atlas pedicle screws were (-6.7±5.2)°, (10.4± 4.3)°, (17.1±3.7)°, respectively; and of the gantry angle were (-0.5±3.5)°, (11.0±5.8)°, (11.5±4.9)°, respectively. The length of screw placement was S 1: (31.1±2.4)mm, S 2: (28.3±2.5)mm, S 3: (29.2±3.8)mm, S 4: (29.6±3.0)mm, respectively ( P<0.05). When the camber angle was from -1°to 5°, the success rate of screw placement was 87.5%; when inserting with 2° camber angle, the success rate was 100%; when the gantry angle was 5°, the success rate was 93.8%. Conclusion:The posterior atlantoaxial transarticular screw combined with atlas pedicle screw can achieve satisfy insertion length and success rate.

Objective:To investigate the efficacy of screw-rod fixation and fusion in revision surgery after percutaneous vertebroplasty (PVP) or percutaneous kyphoplasty(PKP) for osteoporotic vertebral fractures (OVFs).Methods:A retrospective case series study was carried out on clinical data of 19 patients treated by revision surgery after PVP or PKP at Zhejiang Ningbo No.6 Hospital from January 2014 to December 2017. There were 5 males and 14 females, with age of (70.7±6.0)years (range, 58-81 years). Injured segment was located at T 9 in 1 patient, T 11 in 3, T 12 in 5, L 1 fracture in 5, L 2 in 2, L 3 in 2 and L 4 in 1. Caused for revision and operation methods were as follows, 5 patients underwent debridement, screw-rod fixation and fusion due to infection, 9 patients underwent osteotomy due to progressive kyphosis, screw-rod fixation and fusion, 5 patients underwent spinal canal decompression, screw-rod fixation and fusion due to neurological dysfunction. The operation time, intraoperative blood loss, and perioperative complications were recorded. The white blood cell (WBC), erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were used to evaluate the control of infection before operation, before discharge and at postoperative 3 months. The changes in Cobb angle were measured before and after operation and at the final follow-up. The American spinal injury association (ASIA) scale, visual analog scale (VAS) and Oswestry disability index (ODI) were evaluated at the final follow-up. Results:All patients were followed up for 24-46 months [(32.7±8.3)months]. The revision operation time was 135-320 minutes [(226.3±75.6)minutes]. The intraoperative blood loss was 350-1 500 ml [(825.5±230.6)ml]. There were 1 patient with poor wound healing, 2 with pulmonary infection, and 2 with hardware loosening. The WBC, ESR and CRP decreased from preoperative (9.2±1.7)×10 9/L, (88.7±19.2)mm/h, (58.7±22.9)mg/L to (7.3±0.9)×10 9/L, (42.5±13.7)mm/h, (37.3±16.3)mg/L before discharge, and (6.6±0.7)×10 9/L, (26.8±9.5)mm/h, (17.8±8.6)mg/L at postoperative 3 months ( P<0.01). The Cobb angle improved from preoperative (29.3±5.2)° to (4.8±1.2)° ofter operation and (7.3±1.6)° at the final follow-up ( P<0.05). The patients with ASIA grade C ( n=2) and grade D ( n=1) improved to grade E, and the patients with ASIA grade C ( n=2) improved to grade D at the final follow-up. Imagines showed good bone fusion in all patients at the last follow-up. The mean VAS decreased from preoperative (7.5±0.8)points to (2.1±0.5)points at the last follow-up ( P<0.05). The ODI decreased from preoperative (60.7±15.2)% to (19.9±5.9)% at the last follow-up ( P<0.05). Conclusion:For patients with OVFs undergoing revision surgery after PVP or PKP, debridement, kyphosis correction, spinal canal decompression combined with screw-rod fixation and fusion can reduce infection, correct kyphotic deformity, improve neurological function, relieve pain and improve quality of life.

Objective: To compare the clinical efficacy of posterior atlantoaxial screw-rod fixation combined with spinous process muscle-vessel complex bone graft or iliac bone graft for atlantoaxial instability. Methods: A retrospective case-control study was conducted to analyze the clinical data of 56 patients with atlantoaxial instability admitted to the Sixth Hospital of Ningbo from September 2014 to October 2016. There were 35 males and 21 females, with the age range from 9 to 59 years [(50.3±3.2)years]. A total of 26 patients were treated with posterior atlantoaxial screw-rod fixation combined with spinous process muscle-vessel complex bone graft (complex group), while 30 patients were treated with iliac bone graft (ilium group). Patients showed different degrees of neck pain and limited neck activity preoperatively. X-ray films and three-dimensional CT examination of the cervical spine were taken before and after operation for evaluating the atlantoaxial reduction, bone graft fusion and internal fixation. The operation time, intraoperative bleeding, bone fusion time, visual analogue scale (VAS), Japanese Orthopaedic Association (JOA) score, atlantodental interval (ADI) and axial symptoms were compared between the two groups, and the complications were recorded. Results: Both groups were followed up for 24-30 months, with an average of 27.4 months. In the complex group and the ilium group, the operation time was (2.21±0.25)hours and (2.72±0.26)hours (P<0.01); the intraoperative blood loss was (227.3±45.4)ml and (277.7±43.4)ml, respectively (P<0.05); the bone fusion time was (6.9±0.5)months and (8.1±1.8)months (P>0.05), respectively. In the complex group, the VAS was (5.45±0.69)points before operation, (2.64±0.51)points at the follow-up one month after operation, (0.91±0.7)points at the follow-up 12 months after operation, and (0.45±0.16)points at the follow-up 24 months after operation; and in the ilium group, the VAS was (5.18±0.75)points, (2.45±0.52)points, (1.27±0.19)points and (0.41±0.18)points correspondingly. In terms of VAS, there were significant differences before and after operation within each group (P<0.01), while there were no significant differences between the two groups at different time points (P>0.05). In the complex group, the JOA score was (10.82±0.35)points before operation, (12.73±0.65)points at the follow-up one month after operation, (15.18±0.61)points at the follow-up 12 months after operation, and (15.64±0.15)points at the follow-up 24 months after operation; and in the ilium group, the JOA score was (10.73±1.19)points, (13.01±0.63)points, (14.73±0.91)points and (15.55±0.51)points correspondingly. In terms of JOA score, there were significant differences between before and after operation within each group (P<0.01), while there were no significant differences between the two groups at different time points (P>0.05). In the complex group, the ADI was (2.28±0.59)mm before operation, (1.83±0.56)mm at the follow-up one month after operation, (1.71±0.56)mm at the follow-up 12 months after operation, and (1.59±0.67)mm at the follow-up 24 months after operation; and in the ilium group, the ADI was (2.23±0.60)mm, (1.80±0.18)mm, (1.67±0.69)mm and (1.62±0.53)mm correspondingly. In terms of ADI, there were significant differences between before and after operation within each group (P<0.01), while there were no significant differences between the two groups at different time points (P>0.05). The axial symptom scores were graded as excellent in 23 patients and good in three patients of the complex group while excellent in 21 patients and good in nine patients in the ilium group (P>0.05). There were no patients with spinal nerve injury caused by pedicle screw placement after operation. One patient in the ilium group had incision errhysis and recovered after dressing change, and other patients had no incision infection. Conclusions For atlantoaxial instability, posterior atlantoaxial screw-rod fixation combined with spinous process muscle-vessel complex bone graft or autogenous iliac bone graft can both achieve satisfactory clinical results. The spinous process-muscle-vascellum complex graft has less operation time and intraoperative bleeding than the autogenous iliac bone graft, which can be a feasible alternative operation.

Objective: To observe the endoscopic morphology of gastric varices of patients with portal hypertension type one isolated gastric varices (IGV-1) and to explore the etiology, treatment and prognosis of portal hypertension IGV-1. Methods: From January 2006 to June 2018, at Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine and North Branch of Ruijin Hospital, 54 patients with portal hypertension IGV-1 were retrospectively analyzed. The varices were classified according to the endoscopic morphology and the etiology treatment, therapeutic efficacy and prognosis were also analyzed. Descriptive method was used for statistical analysis. Results: Among the 54 patients with portal hypertension IGV-1, the endoscopic morphology of varices were tuber type in 24 patients (44.4%), grape string type in nine patients (16.7%), strip type in five patients (9.3%), dendritic type in three patients (5.6%) and mixed type in 13 patients(24.1%). Etiological analysis showed that the primary disease of 34 cases (63.0%) were hepatogenic, 11 cases (20.4%) were pancreatic origin, and nine cases (16.7%) were from other diseases. As to treatment, three cases (5.6%) were treated with adhesive, two cases (3.7%) were treated with sclerotherapy, and 49 cases (90.7%) were treated with combination of adhesive and sclerotherapy. Therapeutic efficacy evaluation showed that 46 cases (85.2%) were significantly effective, eight cases were effective, 0 case was ineffective, and all the 54 cases (100.0%) were improved. The prognostic analysis showed that 35 cases (64.8%) had no bleeding in five years and eight cases (14.8%) had no bleeding in 10 years. Nine patients (16.7%) died, including six cases of pancreatic cancer, two cases of liver failure and one case of gastrointestinal bleeding. Conclusions The endoscopic morphology of IGV-1 portal hypertension in mainly tuber type. The main cause is hepatogenic and the combination of adhesive and sclerotherapy is beneficial to the regression of gastric varices.

Objective: To investigate the accuracy and feasibility of individual 3D printing model for pedicle screw placement in treating patients with upper cervical spine fracture. Methods: A retrospective case control study was conducted to analyze the clinical data of 30 patients with upper cervical spine fracture admitted to Ningbo No.6 Hospital from August 2013 to December 2018. There were 19 males and 11 females, aged 45-67 years with an average age of 53.5 years. The 15 patients in the study group were treated with pedicle screw fixation and another 15 patients in the control group were treated with traditional freehand screw fixation. A total of 120 pedicle screws were implanted, with 60 screws in each group. The operation time, intraoperative blood loss, preoperative and postoperative visual analogue score (VAS), Japan Orthopedic Association (JOA) score were recorded. The position and grade of screws were evaluated according to Kawaguchi's evaluation method of screw grade after operation. The patients took monthly reexamination for the first three months after discharge. In the first two months after discharge, the patients took X-ray examination for observation of screw loosening or rupture of internal fixation. At the third month after operation, the patients took CT of cervical spine for observation of bone healing and fusion. Results: The mean follow-up duration was 17.8 months (range, 13-21 months). The study group had shorter operation time (99.13±3.04)minutes compared with the control group (107.00±6.92) minutes (P<0.01). There were no significant differences in intraoperative blood loss, preoperative VAS, JOA scores before operation and 1 year after operation between the two groups (P>0.05), but the VAS in study group was significantly lower than that in control group (P<0.05). In the study group, the VAS score 1 year after operation [(2.3±0.5)points] was lower than that before the operation [(7.7±0.7)points], and the JOA score [(16.8±0.4)points] was significantly higher than that before the operation [(15.9±0.7)points](P<0.01). In the control group, the VAS 1 year after operation [(2.5±0.5)points] was significantly lower than that before operation [(7.5±0.5)points] (P<0.01), and the JOA score [(16.5±0.5)points] was significantly higher than that before operation [(15.9±0.8)points] (P<0.05). In the study group, according to the CT results, there were 28 atlas pedicle screws of grade 0 (93.3%), two of grade 1 (6.7%), 0 of grade 2, 0 of grade 3, and there were 27 axial pedicle screws of grade 0 (90.0%), three of grade 1 (10.0%), 0 of grade 2, and 0 of grade 3. In the control group, there were 25 atlas pedicle screws of grade 0 (83.3%), four of grade 1 (13.3%), one of grade 2 (3.4%), 0 of grade 3, and there were 27 axial pedical screws of grade 0 (90.0%), three of grade 1 (10.0%), 0 of grade 2, and 0 of grade 3. There was no significant difference in the accuracy of pedicle screw placement between the two groups (P>0.05). No serious complications such as spinal cord or vertebral artery injury occurred. At 3 months after operation, CT showed that the fracture of cervical vertebra healed. Conclusion Individualized 3D printed cervical spine model can guide the pedicle screw placement for upper cervical spine fracture, which can shorten the operation time, reduce the postoperative pain of patients, improve the accuracy of screw placement, and reduce the risks related to operation.