BACKGROUND:Optimal treatment for osteoporotic thoracolumbar burst fractures (TLBFs) remains controversial. Therefore, identifying a more effective and feasible method to simplify reported surgical procedures remains crucial. In this study, we aimed to assess the clinical and radiological outcomes of a novel hybrid surgery involving unilateral extrapedicular percutaneous kyphoplasty combined with six-screw fixation in patients with osteoporotic TLBFs. METHODS:Fifty-one patients who underwent this procedure at 2 institutions between January 2019 and October 2023 were retrospectively enrolled. Back pain and function were evaluated using the visual analog scale and Oswestry disability index scores, respectively. Radiological outcomes included the anterior vertebral height, posterior vertebral height, and local kyphotic angle. The intraoperative data and complications were recorded. RESULTS:All patients underwent successful treatment. The postoperative visual analog scale and Oswestry disability index scores significantly decreased (P < 0.05) and continued to decrease at the last follow-up (P < 0.05). Postoperative anterior vertebral height of injured vertebrae, posterior vertebral height of injured vertebrae, and local kyphotic angle values were significantly corrected compared with the respective preoperative values (P < 0.05). No obvious loss of correction was observed during follow-up (P > 0.05). In 50 patients (98%), the cement diffused across the vertebral body midline. Three patients (5.8%) experienced asymptomatic cement leakage. No patient experienced other severe complications, including injuries to the segmental lumbar arteries and nerve roots, internal fixation failures, or deep infections. CONCLUSIONS:The extrapedicular puncture technique avoided internal fixation obstruction and simplified the surgical procedure. This novel hybrid surgery showed good clinical and radiological outcomes. Therefore, it is considered safe and effective for osteoporotic TLBFs.

OBJECTIVE:To explore preemptive analgesic effect of preoperative intramural tramadol injection in percutaneous kyphoplasty (PKP) of vertebrae following local anesthesia. METHODS:From August 2019 to June 2021, 118 patients with thoraco lumbar osteoporotic fractures were treated and divided into observation group and control group, with 59 patients in each gruop. In observation group, there were 26 males and 33 females, aged from 57 to 80 years old with an average of (67.69±4.75)years old;14 patients on T11, 12 patients on T12, 18 patients on L1, 15 patients on L2;tramadol with 100 mg was injected intramuscularly half an hour before surgery in observation group. In control group, there were 24 males and 35 females, aged from 55 to 77 years old with an average of (68.00±4.43) years old;19 patients on T11, 11 patients on T12, 17patients on L1, 12 patients on L2;the same amount of normal saline was injected intramuscularly in control group. Observation indicators included operation time, intraoperative bleeding, visual analogue scale (VAS) evaluation and recording of preoperative (T0), intraoperative puncture(T1), and working cannula placement (T2) between two groups of patients, at the time of balloon dilation (T3), when the bone cement was injected into the vertebral body (T4), 2 hours after the operation (T5), and the pain degree at the time of discharge(T6);adverse reactions such as dizziness, nausea and vomiting were observed and recorded;the record the patient's acceptance of repeat PKP surgery. RESULTS:All patients were successfully completed PKP via bilateral pedicle approach, and no intravenous sedative and analgesic drugs were used during the operation. There was no significant difference in preoperative general data and VAS(T0) between two groups (P>0.05). There was no significant difference in operation time and intraoperative blood loss between the two groups (P>0.05). VAS of T1, T2, T3, T4 and T5 in observation group were all lower than those in control group(P<0.05), and there was no significant difference in T6 VAS (P>0.05). T6 VAS between two groups were significantly lower than those of T0, and the difference was statistically significant (P<0.05). There was no significant difference in incidence of total adverse reactions between two groups (P>0.05). There was a statistically significant difference in the acceptance of repeat PKP surgery (P<0.05). CONCLUSION:Half an hour before operation, intramuscular injection of tramadol has a clear preemptive analgesic effect for PKP of single-segment thoracolumbar osteoporotic fracture vertebral body under local anesthesia, which could increase the comfort of patients during operation and 2 hours after operation, and improve patients satisfaction with surgery.

BackgroundOsteoporosis vertebral compression fractures (OVCF) are common with the aging process. This study aimed to compare the effects of unilateral transverse process extrapedicular (UEPKP) and bilateral transpedicular percutaneous kyphoplasty (BTPKP) for patients with thoracolumbar OVCF.MethodsData from 136 patients with OVCF treated with single-level PKP in our hospital between May 2019 and April 2021 were studied. Patients were grouped based on surgical procedure: there were 62 patients in the UEPKP group and 74 in the BTPKP group. All clinical and radiological data were collected from medical records. Clinical outcomes, including visual analog scale (VAS), Oswestry Disability Index (ODI), and Japanese Orthopaedic Association (JOA) scores of the lumbar spine, were evaluated preoperatively, postoperatively, and at the follow-up visit. The radiological evaluations (anterior vertebral height rate and local kyphosis angle) and complications were also collected.ResultsAll patients had successfully improved after surgery. In the UEPKP group, patients showed a significantly shorter operating time and lower fluoroscopy frequency than patients in the BTPKP group (p < 0.05). However, a significantly better distribution score and cement volume were found in the BTPKP group (p < 0.05). The UEPKP group achieved a significantly better VAS score (0.6 ± 0.5 vs. 0.9 ± 0.8) and ODI (24.7 ± 3.1 vs. 27.5 ± 1.8) at the final follow-up visit than the BTPKP group (p < 0.05). The UEPKP group showed significantly worse radiological outcomes (anterior height rate and local kyphosis angle) at the 6- and 12-month follow-ups (p < 0.05). As for complications, the UEPKP group showed significantly fewer facet joint violations and intraspinal leakages (p < 0.05).ConclusionUEPKP could be a safe and effective alternative procedure for patients with thoracolumbar osteoporotic vertebral compression fracture, which possesses an apparent advantage in reducing intraspinal leakage and facet joint violation over BTPKP.

OBJECTIVE: Posterior single -door laminoplasty is a widely practiced clinical procedure, but the occurrence of postoperative axial syndrome (AS) remains a significant concern. The aim of this study was to identify risk factors associated with AS and develop a risk prediction model. METHODS: Clinical data from 226 patients who underwent posterior single -door laminoplasty between June 2017 and June 2022 were collected. Through Logistic model analysis, the risk factors of AS are clarified and the intensity of each risk factor is explained in the form of forest plot. Subsequently, we constructed a predictive model and plotted receiver operating characteristic curves to assess the model 's predictive value. RESULTS: In the end, 87 cases were diagnosed with AS, resulting in an incidence rate of 38.5%. Logistic regression analysis revealed that preoperative encroachment rate of anterior spinal canal (pre -op ERASC), intraoperative facet joints destruction, intraoperative open-door angle, postoperative loss of cervical curvature, and postoperative loss of cervical range of motion were independent risk factors for AS. Conversely, preoperative cervical curvature (pre -op CC) and postoperation early function training were protective factors against AS. The Youden index indicated that the cutoff values for pre -op ERASC and pre -op CC were 26.6 degrees and 16.5, respectively. The risk prediction model for AS was constructed and a nomogram was plotted. The model has high clinical value. CONCLUSIONS: Pre -op ERASC, pre -op CC, intraoperative facet joints destruction, intraoperative open-door angle, postoperative loss of cervical curvature, postoperative loss of cervical range of motion, and postoperation early function training are independent influencing factors for AS occurrence. The risk model has good practicability.

Purpose Non-specific low back pain (NLBP) is a common clinical condition that affects approximately 60–80% of adults worldwide. However, there is currently a lack of scientific prediction and evaluation systems in clinical practice. The purpose of this study was to analyze the risk factors of NLBP and construct a risk prediction model. Methods We collected baseline data from 707 patients who met the inclusion criteria and were treated at the Sixth Hospital of Ningbo from December 2020 to December 2022. Logistic regression and LASSO regression were used to screen independent risk factors that influence the onset of NLBP and to construct a risk prediction model. The sensitivity and specificity of the model were evaluated by tenfold cross-validation, and internal validation was performed in the validation set. Results Age, gender, BMI, education level, marital status, exercise frequency, history of low back pain, labor intensity, working posture, exposure to vibration sources, and psychological status were found to be significantly associated with the onset of NLBP. Using these 11 predictive factors, a nomogram was constructed, and the area under the ROC curve of the training set was 0.835 (95% CI 0.756–0.914), with a sensitivity of 0.771 and a specificity of 0.800. The area under the ROC curve of the validation set was 0.762 (95% CI 0.665–0.858), with a sensitivity of 0.800 and a specificity of 0.600, indicating that the predictive value of the model for the diagnosis of NLBP was high. In addition, the calibration curve showed a high degree of consistency between the predicted and actual survival probabilities. Conclusion We have developed a preliminary predictive model for NLBP and constructed a nomogram to predict the onset of NLBP. The model demonstrated good performance and may be useful for the prevention and treatment of NLBP in clinical practice.

To analyze the risk factors of contralateral symptomatic foraminal stenosis (FS) after unilateral transforaminal lumbar interbody fusion (TLIF) and to guide and standardize the operation process of unilateral TLIF to reduce the occurrence of contralateral symptomatic FS. A retrospective study was undertaken on 487 patients with lumbar degeneration who underwent unilateral TLIF in the Department of Spinal Surgery of Ningbo Sixth Hospital between January 2017 and January 2021, comprising 269 males and 218 females, with a mean age of 57.1 years (range, 48–77 years). Cases of intraoperative improper operations, such as screw deviation, postoperative hematoma, and contralateral disc herniation, were excluded, and cases of nerve root symptoms caused by contralateral FS were analyzed. Post-surgery, 23 patients with nerve root symptoms caused by contralateral FS were categorized as group A, and 60 patients without nerve root symptoms were randomly selected as group B during the same period. The general data (gender, age, body mass index (BMI), bone mineral density (BMD), and diagnosis) and imaging parameters before and after operation (including contralateral foramen area (CFA), lumbar lordosis angle (LL), segmental lordosis angle (SL), disc height (DH), foramen height (FH), foramen width (FW), fusion cage position, and the difference between postoperative and preoperative) were compared between the two groups. Univariate analysis was performed, and multivariate analysis was undertaken through logistics analysis to determine the independent risk factors. Additionally, the clinical outcomes of the two groups were compared immediately before surgery and one year after surgery, using the visual analogue scale (VAS) score and the Japanese Orthopaedic Association (JOA) score for evaluation. The patients in this study were followed up for a period of 19–25 (22.8atien months. Among them, 23 cases (4.72% incidence) were diagnosed with contralaterally symptomatic FS after the surgery. Univariate analysis indicated significant differences between the two groups in CFA, SL, FW, and cage coronal position. Logistic regression analysis identified preoperative contralateral foramen area (OR = 1.176, 95% CI (1.012, 1.367)), small segmental lordosis angle (OR = 2.225, 95% CI (1.124, 4.406)), small intervertebral foramen width (OR = 2.706, 95% CI (1.028, 7.118)), and cage coronal position not crossing the midline (OR = 1.567, 95% CI (1.142, 2.149)) as independent risk factors for contralateral symptomatic FS after unilateral TLIF. However, there was no statistically significant difference in the pain VAS score between the two groups one year after the operation. In contrast, there was a significant difference in the JOA score between the two groups. The identified risk factors for contralateral symptomatic FS after TLIF include preoperative contralateral intervertebral foramen stenosis, a small segmental lordosis angle, a small intervertebral foramen width, and the coronal position of the cage not crossing the midline. For patients with these risk factors, it is recommended to carefully lock the screw rod during the recovery of lumbar lordosis and ensure that the coronal position of the fusion cage is implanted beyond the midline. If necessary, preventive decompression should also be considered. However, this study did not quantify the imaging data for each risk factor, and further research is needed to improve our understanding of the topic.

Background Laminoplasty (LP), a procedure commonly used to treat cervical spondylotic myelopathy (CSM), often results in the development of axial symptoms (AS) postoperatively. This study aims to analyze the risk factors associated with the occurrence of AS after LP. Methods We collected and evaluated clinical data from 264 patients with CSM who underwent LP treatment at our institution from January 2018 to January 2022 through a single-center retrospective study. Of the patients, 153 were male and 111 were female, with an average age of 58.1 ± 6.7 years. All patients underwent C3-7 posterior laminoplasty. Based on the occurrence of postoperative axial symptoms, the patients were divided into an AS group and a non-AS group. General information, including age, gender, disease duration, Japanese Orthopaedic Association (JOA) score, postoperation early function training, and collar-wearing time, was recorded and compared between the two groups. Surgical-related data, such as operative segments, surgical time, intraoperative blood loss, intraoperative facet joint destruction, and destruction of the C7 spinous process muscle insertion, were also compared. Imaging data, including preoperative cervical curvature, cervical range of motion, preoperative encroachment rate of the anterior spinal canal, and angle of laminar opening, were collected. Univariate and multivariate logistic regression analyses were used to identify risk factors for the development of AS after LP, and receiver operator characteristic (ROC) curves were utilized to explore the optimal preoperative parameters. Results All 264 patients successfully underwent surgery and were followed up for an average of 19.5 ± 6.8 months. At the 6-month follow-up, 117 patients were diagnosed with AS, resulting in an incidence rate of 40.2%. The multivariate logistic regression analysis identified that preoperative encroachment rate of anterior spinal canal (Pre-op ERASC), intraoperative facet joints destruction (Intra-op FJD), intraoperative open-door angle (Intra-op OA), destroy the C7 spinous process muscle insertion (Destroy C7 SPMI), postoperative loss of cervical curvature (Post-op LCC), and postoperative loss of cervical range of motion (Post-op LCROM) were independent risk factors for AS. Conversely, preoperative cervical curvature (Pre-op CC) and postoperation early function training (Post-op EFT) were protective factors against AS. According to the ROC curve, the cutoff values for preoperative anterior spinal canal occupation rate and preoperative cervical curvature were 28.5% and 16.5°, respectively. When the preoperative anterior spinal canal occupation rate was greater than 28.5% or the preoperative cervical curvature was less than 16.5°, AS was more likely to occur after surgery. Conclusion High preoperative anterior spinal canal occupation rate, facet joint damage during surgery, C7 spinous process muscle stop point damage, larger angle of laminar opening, and greater postoperative cervical curvature loss and cervical range of motion loss are associated with an increased risk of developing AS after cervical laminoplasty. Conversely, a larger preoperative cervical curvature and early postoperative functional exercises can help reduce the occurrence of AS.

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.

To evaluate the correlation between the degree of preoperative contralateral foraminal stenosis(CFS) and the incidence of contralateral root symptoms after unilateral transforaminal lumbar interbody fusion(TLIF) and to evaluate the appropriate candidate of preventive decompression according to the degree of preoperative contralateral foraminal stenosis. An ambispective cohort study was conducted to investigate the incidence of contralateral root symptoms after unilateral transforaminal lumbar interbody fusion (TLIF) and the effectiveness of preventive decompression. A total of 411 patients were included in the study, all of whom met the inclusion and exclusion criteria and underwent surgery at the Department of Spinal Surgery, Ningbo Sixth Hospital, between January 2017 and February 2021. The study was divided into two groups: retrospective cohort study A and prospective cohort study B. The 187 patients included in study A from January 2017 to January 2019 did not receive preventive decompression. They were divided into four groups based on the degree of preoperative contralateral intervertebral foramen stenosis: no stenosis group A1, mild stenosis group A2, moderate stenosis group A3, and severe stenosis group A4. A Spearman rank correlation analysis was used to evaluate the correlation between the preoperative contralateral foramen stenosis degree and the incidence of contralateral root symptoms after unilateral TLIF. From February 2019 to February 2021, 224 patients were included in the prospective cohort group B. The decision to perform preventive decompression during the operation was based on the degree of preoperative contralateral foramen stenosis. Severe intervertebral foramen stenosis was treated with preventive decompression as group B1, while the rest were not treated with preventive decompression as group B2. The baseline data, surgical-related indicators, the incidence of contralateral root symptoms, clinical efficacy, imaging results, and other complications were compared between group A4 and group B1. All 411 patients completed the operation and were followed up for an average of 13.5 ± 2.8 months. In the retrospective study, there was no significant difference in baseline data among the four groups (P > 0.05). The incidence of postoperative contralateral root symptoms increased gradually, and a weak positive correlation was found between the degree of preoperative intervertebral foramen stenosis and the incidence of postoperative root symptoms (rs = 0.304, P < 0.001). In the prospective study, there was no significant difference in baseline data between the two groups. The operation time and blood loss in group A4 were less than those in group B1 (P < 0.05). The incidence of contralateral root symptoms in group A4 was higher than that in group B1 (P = 0.003). However, there was no significant difference in leg VAS score and ODI index between the two groups at 3 months after the operation (P > 0.05). There was no significant difference in cage position, intervertebral fusion rate, and lumbar stability between the two groups (P > 0.05). No incisional infection occurred after the operation. No pedicle screw loosening, displacement, fracture, or interbody fusion cage displacement occurred during follow-up. This study found a weak positive correlation between the degree of preoperative contralateral foramen stenosis and the incidence of contralateral root symptoms after unilateral TLIF. Intraoperative preventive decompression of the contralateral side may prolong the operation time and increase intraoperative blood loss to some extent. However, when the contralateral intervertebral foramen stenosis reaches the severe level, it is recommended to perform preventive decompression during the operation. This approach can reduce the incidence of postoperative contralateral root symptoms while ensuring clinical efficacy.

Objective:To investigate the safety and efficacy of short-segment fixation covering the fractured vertebrae via posterior intermuscular approach plus percutaneous kyphoplasty (PKP) through the outer upper edge of the base of the fractured vertebral pedicle in the treatment of osteoporotic thoracolumbar burst fracture.Methods:A retrospective case series study was used to analyze the clinical data of 56 patients with osteoporotic thoracolumbar burst fracture admitted to Ningbo No.6 Hospital from January 2018 to February 2021, including 24 males and 32 females; aged 56-72 years [(63.5±4.6)years]. All patients underwent short-segment fixation covering the fractured vertebrae via posterior intermuscular approach combined with PKP through the outer upper edge of the base of the fractured vertebral pedicle. The operation time, intraoperative blood loss, hospitalization day and surgery-related complications were recorded. The visual analogue score (VAS) of back pain, ratios of the anterior, middle and posterior height of the fractured vertebrae and kyphotic Cobb angle were compared before operation, at postoperative 2 days and at the final follow-up.Results:All patients were followed up for 12-28 months [(14.5±2.2)months]. The operation time was 55-85 minutes [(62.0±12.1)minutes], intraoperative blood loss was 80-150 ml [(94.0±18.5)ml], and hospitalization day was 5-9 days [(7.4±1.1)days]. Based on CT examination at postoperative 2 days, there were 2 patients with paravertebral cement leakage, 2 with intervertebral space leakage and 1 with intracanal leakage, but none reported associated clinical symptoms. No implant failure or fractures of adjacent segments was detected during the follow-up period. The VAS was significantly decreased from preoperative (7.5±1.2)points to (3.2±0.8)points at postoperative 2 days ( P<0.01), and the score was further lowered to (2.2±0.8)points at the final follow-up when compared with that at postoperative 2 days ( P<0.01). The ratios of the anterior, middle and posterior height of the fractured vertebrae and kyphotic Cobb angle were significantly improved at postoperative 2 days [(89.5±13.2)%, (85.8±7.9)%, (89.5±9.0)% and (5.6±3.2)°] when compared with those before operation [(48.9±11.8)%, (61.9±11.9)%, (79.9±9.8)% and (26.3±5.6)°] (all P<0.01). Slight losses were observed in the ratios of the anterior, middle and posterior height of the fractured vertebrae and kyphotic Cobb angle at the final follow-up [(87.0±12.7)%, (82.1±7.8)%, (88.6±10.0)% and (5.4±3.2)°], but not significantly different from those at postoperative 2 days (all P>0.05). Conclusion:Short-segment fixation covering the fractured vertebrae via posterior intermuscular approach plus PKP through the outer upper edge of the base of the fractured vertebral pedicle can safely and effectively treat osteoporotic thoracolumbar burst fracture, for it can significantly improve back pain, restore the height of the fractured vertebrae and correct the kyphotic deformity.

Objective:To investigate the anatomical safety and feasibility ofposterior occipitocervical fixation with atlan-tooccipital-clivus screw.Methods:Data of 60 patients who treated in the spinal department of our hospital with upper cervical computed tomographic scans from February 2017 to November 2019 were retrospectively collected. Occipitocervical infection, injury, tumor and deformity were excluded. The Mimics software was used to reconstruct the occiput, atlas and measure the anatomical parameters, including the height and width of the anterior edge of the clivus, the height and width of the middle part of the clivus, the thinnest distance of the soft tissue in front of the clivus, the anteroposterior diameter, transverse diameter, the angle of inside tilting in coronary plane of the occipital condyle, the distance from the hypoglossal canal to the atlantooccipital articular surface, the anteroposterior diameter and transverse diameter of the superior joint of atlas, the height of the lateral mass, and the height and transverse diameter of the inferior articular process of the superior atlas joint. The three-dimensional digital modeling was performed and the screw diameter of 3.5mm was simulated. 3-Matic software were used to measure the screw placement parameters, including the inside tilting angle in coronary plane of screw, and the angle of upper tilting in sagittal plane and length of screw. The atlanto-occipital junction was exposed at the rear of 8 cadavers. According to the above parameters, the titanium alloy screws with a diameter of 3.5 mm were transferred from the inferior articular process and posterior arch of the atlas to the clivus through the atlantooccipital. Finally, the screw path was cut along the nail path with a pendulum saw, and the track of the screw was observed to confirm the safety and effectiveness of the screw.Results:The leading edge height and width of male clivus was 16.8±2.5 mm and 20.1±3.1 mm. The middle part of the clivus was 9.7±2.3 mm and 22.4±3.7 mm. The thinnest soft tissue in front of the clivus was 5.8±1.48 mm. The anteroposterior diameter of the occipital condyle was 19.1±1.9 mm, the transverse diameter was 12.6±2.0 mm, the inside tilting angle was 33.7°±4.5°, and the vertical distance from the lowest point of the neural tube to the articular surface of the occipital condyle was 9.6±1.1 mm. The height of the lateral mass of atlas was 12.9±2.4 mm, the anteroposterior diameter of the upper joint of atlas was 21.7±1.9 mm, and the transverse diameter was 11.7±1.4 mm. The width of the inferior facet was 14.9±1.4 mm and the height of the inferior facet was 5.7±0.85 mm. The distance from the screw entry point to the vertical line of the lateral mass migration midpoint was 2.5±0.6 mm; The distance from the screw entry point to the horizontal line of the midpoint was 2.3±0.7 mm.The inside titling angle of screw was 18.4°±1.6°, the upper tilting angle was 55.6°±3.1°, the length of the screw track was 53.0±2.8 mm, the adjustment range of upper tilting angle was 15.0±2.8 mm, the adjustment range of inside tilting angle was 10.4±2.4 mm. The anatomical parameters of females were slightly smaller than those of males, and the difference was statistically significant, but there was no significant difference between left and right parameters. The screws of 8 specimens could be inserted safely and effectively.Conclusion:Atlan-tooccipital-clivus screw can be implanted without damaging the nerve and vascular structure, and it can be used as a choice for occipitocervical fixation.

OBJECTIVE:To explore the treatment strategy and clinical efficacy for os odontoideum complicated with atlantoaxial dislocation.METHODS:The clinical data of 17 patients with os odontoideum complicated with atlantoaxial dislocation surgically treated from January 2006 to January 2015 were retrospectively analyzed, including 7 males and 10 females, aged 17 to 53 (43.1±11.3) years old;course of disease was 3 to 27(10.2±6.9) months. All patients received cranial traction before operation, 12 of 14 patients with reducible dislocation were treated by posterior atlantoaxial fixation and fusion, and 2 patients with atlantooccipital deformity were treated by posterior occipitocervical fixation and fusion;3 patients with irreducible alantoaxial dislocation were treated by transoral approach decompression combined with posterior atlantoaxial fixation and fusion. The operation time, intraoperative blood loss and perioperative complications were recorded. Visual analogue scale (VAS) and Japanese Orthopaedic Association (JOA) score were used to evaluate the change of neck pain and neurological function. Atlantoaxial joint fusion rate was evaluated by CT scan.RESULTS:The operation time of posterior fixation and fusion ranged from 86 to 170 (92.2±27.5) min, and the intraoperative blood loss was 200-350 (250.7±65.2) ml. No vertebral artery injury and spinal cord injury were recorded. Among the patients underwent atlantoaxial fixation and fusion, 1 patient with reducible dislocation fixed by C2 laminar screw lost reduction after primary operation, and received anterior release again and finally occipitocervical fusion. All patients were followed up for 15 to 58 (32.0±12.2) months. VAS score was decreased from preoperative 4.2±0.9 to 1.3±0.7 at final follow up and the JOA score was improved from preoperative 11.2±1.2 to 16.9±0.8 at final follow-up. CT scan confirmed that the atlantoaxial or occipitocervical fusion wasgood, and the fusion time was 5 to 9 (6.7±0.6) months.CONCLUSION:Surgical treatment of os odontoideum complicated with atlantoaxial dislocation can achieve satisfactory results, improve the patient's neurological function and improve the quality of life, however the surgical options needs to be individualized.

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.

目的:研究白藜芦醇抑制NLRP3炎症小体活化保护兔脊髓损伤的机制.方法:将50只雄性日本大耳兔随机分成5组:空白对照组(CON组)、脊髓损伤模型组(SCI组)、白藜芦醇低剂量组(RSV(L)组)、白藜芦醇高剂量组(RSV(H)组),甲基强的松龙组(MP组),每组10只.除CON组外的其他4组均制备脊髓损伤模型.每日静脉给药,CON组和SCI组给予等量生理盐水,连续14 d.Tarlov法进行兔神经行为学评分,发色底物法测定脊髓组织MDA含量及SOD和GSH-Px活力,Western blot测定脊髓神经组织NLRP3、Caspase1 p20,IL-1β,Sirt1,NF-κB p65的蛋白表达,HE染色观察脊髓组织病理变化.结果:白藜芦醇增加脊髓损伤兔行为学评分,促进损伤组织的修复,降低脊髓组织MDA含量,增加SOD和GSH-Px活力,下调脊髓组织NF-κB p65的表达,上调Sirt1的表达,抑制炎症小体NLRP3的表达(脊髓组织NL-RP3、Caspase1 p20、IL-1β 的表达均降低).结论:白藜芦醇可促进脊髓损伤兔恢复,其作用机制可能通过激活Sirt1、调节NF-κB通路和体内抗氧化水平,进一步抑制NLRP3炎症小体的活化来发挥作用.

OBJECTIVE To compare the curative effect of short-segment pedicle screw fixation combined with vertebroplasty and injured vertebra pedicle fixation in treating osteoporotic thoracolumbar burst fractures. METHODS A retrospective study was performed for 52 patients with thoracolumbar burst fractures from August 2010 to August 2015. Among them, 27 patients(group A) were treated with short-segment pedicle screw fixation combined with vertebroplasty, including 17 males and 10 females, aged from 54 to 68 years old with an average of(61.01±5.41) years, 16 cases were type A3 and 11 cases were type A4 according the new AO typing. Other 25 patients (group B) were treated with short-segment pedicle screw fixation combined with injured vertebra pedicle fixation, including 12 males and 13 females, aged from 55 to 66 years old with an average of (59.28±6.12) years, 18 cases were type A3 and 7 cases were type A4 according the new AO typing. Operation time, intraoperative bleeding volume, complication, image data and clinical effect were compared between two groups. RESULTS All the patients were followed up for 12 to 15 months with an average of (12.4±2.1)months. There was no significant difference in general data(including gender, age, injured site, preoperative VAS score, Cobb angle, injured vertebral anterior border height) between two groups. There was no significant differences in operation time, intraoperative bleeding volume between two groups. Preoperative, one week after operation and final follow-up, VAS scores were 5.2±0.5, 1.2±0.2, 0.8±0.1 respectively in group A and 5.0±0.6, 2.5±0.4, 1.3±0.2 in group B; injured vertebral anterior border height were (49.4±6.8)%, ( 94.5±1.2)%, ( 94.1±3.7)% respectively in group A and (48.2±7.0)%, ( 94.3±4.1)%, ( 90.0±2.3)% in group B;Cobb angles were (20.4±5.2) °, (2.5±1.8) °, (4.4±1.7)° respectively in group A and (19.8±6.8)°, (2.4±1.7)°, (7.0±1.2)° in group B. At final follow-up, VAS, Cobb angle, injured vertebral anterior border height in two groups were obviously improved(P<0.05). Postoperative at 1 week and final follow-up, VAS score of group A was lower than that of group B(P<0.05);and there was no significant difference in Cobb angle between two groups(P>0.05); there was significant difference in injured vertebral anterior border height between two groups(P<0.05). The complication of internal fixation failure had 1 case in group A and 4 cases in group B. CONCLUSIONS For the treatment of single osteoporotic thoracolumbar burst fractures, short-segment pedicle screw fixation combined with vertebroplasty is better than combined with injured vertebra pedicle fixation in clinical effect, it can relieve pain, maintain injured vertebral height and sagittal alinement, reduce the complications associated with internal fixation, and be worth spread in clinic.

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 investigate the efficacy of microscope-assisted free-hand atlantal pedicle screw technique for unstable atlas burst fracture.Methods A retrospective case control study was conducted to analyze the clinical data of 48 patients with unstable atlas burst fracture admitted to Ningbo No.6 hospital from January 2016 to June 2018.There were 32 males and 16 females,aged 24-72 years [(49.5 ± 15.2 years)].A total of 22 patients were treated with the technique of atlas screw placement by drill under microscope (Group A),including 14 males and eight females,aged 24-68 years.Twenty six patients (Group B) were treated with atlantal pedicle screw placement by hand,including 18 males and 8 females,aged 26-72 years [(50.7 ± 15.4 years)].The operation time,intraoperative blood loss and the times of intraoperative fluoroscopy were compared between the two groups.X-ray and CT were reexamined to evaluate the accuracy of screw placement within one week after operation.The visual analogue score (VAS) and cervical dysfunction index (NDI) were compared before operation and 1 year after operation.The intraoperative complications were recorded.One year after operation,X-ray and CT were reexamined to observe fracture healing,aflantoaxial fusion and failure of internal fixation.Results Group A was followed up for 12-24 months [(18.4 ± 6.8)months],and Group B for 12-24 months [(17.4 ± 7.2) months].The amount of intraoperative bleeding [(180.5 ±60.8) ml] and the times of intraoperative fluoroscopy [(1.3 ±0.8) times] in Group A were significantly lower than those in Group B [(280.1 ± 80.2) ml,(2.2 ± 0.8) times] (P ＜ 0.05),but there was no significant difference in the time of operation and the accuracy of screw placement (P ＞ 0.05).There were statistically significant differences in VAS and NDI before operation and one year after operation in both groups (P ＜ 0.05),but there was no significant difference between the two groups (P ＞ 0.05).No serious complications such as vertebral artery,nerve root and spinal cord injury occurred.One year follow-up CT showed healed fracture or continuous bone bridge passing through the atlantoaxial intervertebral space.Except for one patient in Group B with lost reduction,other patients had no loosening or fracture of internal fixation.Conclusion Compared with screw placement by hand,the pedicle screw placement by drill under the microscope can reduce the amount of bleeding and the times of fluoroscopy.

Objective To compare the clinical and radiological outcome between the modified Broström repair with augmentation using suture tape (MBA) and the modified Broström repair (MB) for patients with chronic lateral ankle instability. Methods A retrospective study was performed in Ningbo No. 6 Hospital. The study included 53 patients who underwent surgical treatment from March 2014 to July 2016 and were followed for 2 years. A total of 25 patients underwent modified Broström repair with augmentation using suture tape, and 28 patients were treated with modified Broström repair. Patients were evaluated using the American Orthopedic Foot and Ankle Scale (AOFAS) hindfoot scale, the Foot and Ankle Ability Measure (FAAM) score, range of motion (ROM), and the visual analogue scale (VAS). The talar tilt angle (TTA) and anterior talar translation (ATT) were used to evaluate the mechanical stability. All radiological outcomes were measured by two orthopaedic surgeons, with the measurements repeated 3 days later. Results The mean age of the patients was 26.6 ± 17.8 years in the MBA group and 28.1 ± 19.4 years in the MB group, and no statistical difference in preoperative data was found between two groups. There were significant differences before and after the operation within the groups. Both groups achieved satisfactory outcomes, and significant improvements (VAS, FAAM, AOFAS, TTA, and ATT) were observed between the 1‐year follow‐up and final follow‐up ( P < 0.05). The MBA group showed significant improvement in the FAAM Sport (87.1 ± 5.4 vs 78.2 ± 12.0, P = 0.001) and total scores (93.1 ± 2.3 vs 90.5 ± 5.1, P = 0.027) at the final follow‐up compared with the MB group, and for the other outcomes, there were no significant differences between the two groups. Conclusion The modified Broström repair with augmentation using suture tap for chronic lateral ankle instability achieves a better outcome; however, further research is necessary.

BACKGROUND:Spine fractures combined with sternal injury are most commonly occur in the thoracic region. Lower cervical and thoracolumbar injuries have also been reported, especially for the patients with manubriosternal dislocation. The type of spine injury is easily recognized in initial presentation, but we may miss the sternal fracture and manubriosternal dislocation.CASE PRESENTATION:A 23-year-old male patient complained with chest, right ankle, and lumbar pain after a fall at ground level, with diagnosis of right distal tibial fracture, sternal fracture, calcaneus fracture, and L2 vertebral fracture. However, neurologically he was completely normal. He underwent the operation for his lower extremity and spine, but we missed his manubriosternal dislocation after discharged. After one month, he came to the clinic with complained of chest pain, the imaging exams showed anterior dislocation of manubriosternal joint. We chose conservative treatment for manubriosternal dislocation. He was followed up at monthly intervals and radiographs along with computerized tomography showed satisfactory in fracture healing of lumber and the sternal fracture. However, the manubriosternal dislocation was malunioned. The patient had appearance deformity of the manubriosternal joint.CONCLUSION:This case supports the concept of the existence and clinical relevance of the thoracic cage theory, the thoracolumbar vertebrae should also be included in the thoracic cage theory.