Objective:To compare the safety and efficacy of two different minimally invasive approaches to implant pedicle screw for the treatment of single-segment thoracolumbar spine fractures without nerve injury.Methods:This was a retrospective study. Eighty patients with mono-segmental thoracolumbar fractures treated with minimally invasive pedicle screw fixation at Beijing Friendship Hospital, Capital Medical University from January 2020 to June 2022 were included. There were 46 males and 36 females, the age was (45.93±7.91) years old, and ranged from 27 to 60 years old. They were divided into two groups according to different surgical techniques: percutaneous pedicle screw fixation group ( n=44) and Wiltse approach group ( n=36). The operative time, operative visible blood loss, hidden blood loss, total blood loss, fluoroscopy times, incision length, hospital time after surgery and ambulation time were compared. Visual analogue scale (VAS), Oswestry disability index (ODI), ratio of the vertebral anterior height, angle of injured vertebral endplate were recorded and compared between two groups before surgery and at 3 days, 6 months and 1 year after surgery. The accuracy of pedicle screw position and the facet joint violation rate were evaluated by using the postoperative CT scan. Perioperative related complications were investigated. Normally distributed numerical data were presented as mean ± standard deviation, and differences between the groups were compared using t-test. The counting data were expressed as percentages or rates and compared using χ2 test. Results:All patients were followed for a minimum of 12 months. There is no significant difference between the two groups in intraoperative visible blood loss, hospital time after surgery, ambulation time, postoperative VAS and ODI, ratio of vertebral anterior height and angle of injured vertebral endplate at 3 days after surgery, pedicle screw position accuracy and perioperative complications ( P>0.05). The operative time, hidden blood loss, total blood loss, intraoperative fluoroscopy times, facet joint violation rate in the percutaneous pedicle screw fixation group were remarkably higher than in the Wiltse approach group ( P<0.05). The ratio of vertebral anterior height in the percutaneous pedicle screw fixation group was dramatically lower than in the Wiltse approach group at 6 months and 1 year after surgery ( P<0.05). The postoperative injured vertebral endplate angle was higher in the percutaneous pedicle screw fixation group than that in the Wiltse approach group at 6 months and 1 year ( P<0.05). Conclusions:Both percutaneous pedicle screw fixation and Wiltse approach were safe and effective minimally invasive surgical procedures for the treatment of thoracolumbar fractures without neurological injury. The Wiltse approach can reduce fluoroscopy times and perioperative hidden blood loss, reduce the risk of facet joint violation, and maintain a better reduction than percutaneous pedicle screw fixation.

Three-dimensional ordered porous carbon materials exhibit potential application prospects as excellent drug supports in drug delivery systems due to their high specific surface area, tunable pore structure, and excellent biocompatibility. In this study, three-dimensional ordered porous carbon materials were prepared using Acanthopanax senticosus herbal residues as raw material and KOH as activating agent through a one-step pyrolysis method. The prepared carbon-based material was systematically characterized by powder X-ray diffraction, scanning electron microscopy, N₂ adsorption-desorption and Fourier-transform infrared spectroscopy. The results show that the three-dimensional ordered porous carbon materials prepared with KOH as the activator via pyrolysis possess abundant functional groups, high porosity, and high specific surface area, with a specific surface area of 1 471.6 m²·g^-1. The three-dimensional ordered porous carbon materials prepared at 800 ℃ exhibits a high drug loading capacity (78.0%) and drug release rate (86.8%) for 5-fluorouracil. Three-dimensional orderly porous carbon materials show significant application advantages in drug construction, and their high specific surface area and adjustable pore size structure significantly improve the drug load rate and drug release rate, providing a solid foundation for the development of efficient and accurate drug delivery system.

Purpose::Shaping and assembling contemporary external fixators rapidly for the severe mandibular fractures remains a challenge, especially in emergency circumstance. We designed a novel external fixator that incorporates universal joints to provide the stabilization for mandibular comminuted fractures. This study aims to confirm the efficacy of this novel external fixator through biomechanical tests in vitro and animal experiments. Methods::In vitro biomechanical tests were conducted using 6 fresh canine with mandibular defect to simulate critical comminuted fractures. Three mandibles were stabilized by the novel external fixator and other mandibles were fixed by 2.5 mm reconstruction plates. All fixed mandibles were subjected to loads of 350 N on the anterior regions of teeth and 550 N on the first molar of the unaffected side. The stability was evaluated based on the maximum displacement and the slope of the load-displacement curve. In animal experiments, 9 beagles with comminuted mandibular fractures were divided into 3 groups, which were treated with the novel external fixation, reconstruction plate, and dental arch bar, respectively. The general observation, the changes in animals’ weight, and the surgical duration were recorded and compared among 3 groups. The CT scans were performed at various intervals of 0 day (immediately after the surgery), 3 days, 7 days, 14 days, 21 days, and 28 days to analyze the displacement of feature points on the canine mandible and situation of fracture healing at 28 days. The statistical significance was assessed by the two-way analysis of variance test followed by the Bonferroni test, enabling multiple comparisons for all tests using GraphPad Prism10.1.0 (GraphPad Inc, USA). Results::The outcomes of the biomechanical tests indicated that no statistically significant differences were found in terms of the maximum displacement ( p = 0.496, 0.079) and the slope of load displacement curves ( p = 0.374, 0.349) under 2 load modes between the external and internal fixation groups. The animal experiment data showed that there were minor displacements of feature points between the external and internal fixation groups without statistic difference, while the arch bar group demonstrated inferior stability. The CT analysis revealed that the best fracture healing happened in the internal fixation group, followed by the external fixation and arch baring at 28 days after fixation. The external fixation group had the shortest fixation duration (25.67 ± 3.79) min compared to internal fixation ((70.67 ± 4.51) min, p < 0.001) and arch baring ((42.00 ± 3.00) min, p = 0.046). Conclusion::The conclusion of this study highlighted the efficacy and reliability of this novel external fixator in managing mandibular fractures rapidly, offering a viable option for the initial stabilization of comminuted mandibular fractures in the setting of emergency rescue.

Purpose::This study evaluated the methods and clinical effects of multidisciplinary collaborative treatment for occlusal reconstruction in patients with old jaw fractures and dentition defects.Methods::Patients with old jaw fractures and dentition defects who underwent occlusal reconstruction at the Third Affiliated Hospital of Air Force Military Medical University from January 2018 to December 2022 were enrolled. Clinical treatment was classified into 3 phases. In phase I, techniques such as orthognathic surgery, microsurgery, and distraction osteogenesis were employed to reconstruct the correct 3-dimensional (3D) jaw position relationship. In phase II, bone augmentation and soft tissue management techniques were utilized to address insufficient alveolar bone mass and poor gingival soft tissue conditions. In phase III, implant-supported overdentures or fixed dentures were used for occlusal reconstruction. A summary of treatment methods, clinical efficacy evaluation, comparative analysis of imageological examinations, and satisfaction questionnaire survey were utilized to evaluate the therapeutic efficacy in patients with traumatic old jaw fractures and dentition defects. All data are summarized using the arithmetic mean ± standard deviation and compared using independent sample t-tests. Results::In 15 patients with old jaw fractures and dentition defects (an average age of 32 years, ranging from 18 to 53 years), there were 7 cases of malocclusion of single maxillary fracture, 6 of malocclusion of single mandible fracture, and 2 of malocclusion of both maxillary and mandible fractures. There were 5 patients with single maxillary dentition defects, 2 with single mandibular dentition defects, and 8 with both maxillary and mandibular dentition defects. To reconstruct the correct 3D jaw positional relationship, 5 patients underwent Le Fort I osteotomy of the maxilla, 3 underwent bilateral sagittal split ramus osteotomy of the mandible, 4 underwent open reduction and internal fixation for old jaw fractures, 3 underwent temporomandibular joint surgery, and 4 underwent distraction osteogenesis. All patients underwent jawbone augmentation, of whom 4 patients underwent a free composite vascularized bone flap (26.66%) and the remaining patients underwent local alveolar bone augmentation. Free gingival graft and connective tissue graft were the main methods for soft tissue augmentation (73.33%). The 15 patients received 81 implants, of whom 11 patients received implant-supported fixed dentures and 4 received implant-supported removable dentures. The survival rate of all implants was 93.82%. The final imageological examination of 15 patients confirmed that the malocclusion was corrected, and the clinical treatment ultimately achieved occlusal function reconstruction. The patient satisfaction questionnaire survey showed that they were satisfied with the efficacy, phonetics, aesthetics, and comfort after treatment.Conclusion::Occlusal reconstruction of old jaw fractures and dentition defects requires a phased sequential comprehensive treatment, consisting of 3D spatial jaw correction, alveolar bone augmentation and soft tissue augmentation, and implant-supported occlusal reconstruction, achieving satisfactory clinical therapeutic efficacy.

Objective:To analyze the safety and efficacy of single percutaneous vertebroplasty (PVP) in the treatment of multi-segment osteolytic spinal metastases.Methods:A retrospective analysis was conducted on 113 patients with multi-segment osteolytic spinal metastases treated with PVP at Beijing Friendship Hospital, Capital Medical University from January 2013 to December 2019, including 50 males and 63 females. The age ranged from 47 to 85 years, with a mean of (66.9±1.52) years. Patients were divided into two groups based on the number of affected vertebrae undergoing surgery: the conventional surgery group ( n=72), with a maximum of three vertebral bodies undergoing PVP during each surgery; the multivertebral surgery group ( n=41), received PVP on more than three vertebral bodies in one surgery. Visual analogue scale(VAS) of pain, Oswestry disability index (ODI), general health status (GH), and mental health status (MH) were assessed before and after PVP to evaluate the efficacy of the procedure. Complications of the patients were systematically assessed to evaluate safety. Measurement data was expressed as mean±standard deviation( ± s), independent sample t-test was used for inter-group comparison, and paired sample t-test was used for intra-group comparison; the comparison of count data was conducted using Chi-square test. Results:After 6 months of surgery, the ODI score, GH score and MH score of the conventional surgery group was (35.28±1.74)%, 57.85±2.11 and 61.20±3.67, all of which improved significantly compared to before surgery, and the difference was statistically significant ( P<0.05). After 6 months of surgery, the ODI score, GH score and MH score of the multivertebral surgery group was (35.67±1.92)%, 64.12±1.35 and 59.80±3.81, all of which improved significantly compared to before surgery, and the difference was statistically significant ( P<0.05). There was no significant difference in ODI score and MH score between the two groups after 6 months of surgery ( P>0.05). At one week after surgery, the pain VAS score in the conventional surgery group (3.51±0.21) was lower than that in the multivertebral surgery group (3.98±0.32), and the difference was statistically significant ( P<0.05). GH score in the conventional surgery group showed significantly greater improvement than that in the multivertebral surgery group after 6 months of surgery, and the difference was statistically significant ( P<0.05). Bone cement leakage occurred in 21 vertebra of the conventional surgery group, and 24 vertebra of the multivertebral surgery group, with leakage rates of 14.8% and 13.0%, respectively, with no statistical significance between the two groups ( P>0.05). Conclusions:Single PVP surgery can safely and effectively alleviate the pain of multi-segment osteolytic spinal metastases and improve spinal mobility. Meanwhile, improving mental health and reducing functional impairments. But the short-term pain relief and long-term general health of the multivertebral surgery group were lower than those of the conventional surgery group.

Objective:To explore interspinous fusion capacity after interspinous distraction fusion (ISDF) device implantation, a preliminary biomechanical analysis and histological evaluation were performed.Methods:The experimental animals were procured from the Science and Research Laboratory Animal Center of Beijing Friendship Hospital, Capital Medical University. The animals were 8-9 weeks old and with an average weight of 25 kg. 15 mini-pigs were randomly divided into three groups, the sham operation group, the decompression group and the ISDF fixed decompression group, 5 animals per group. The sham operation group was treated with simple incision and exposed lamina suture. The decompression group received unilateral decompression and the ISDF fixed decompression group experienced unilateral hemilaminectomy decompression and ISDF fixation. The graft-bed site was filled with purified bone graft material without any autograft bone. After 6 months feeding, all experimental animals were sacrificed and the corresponding lumbar vertebrae was obtained. The samples were fixed on the spinal test system and the range of motion of flexion-extension, lateral bending and rotation were tested through a multiaxial robotic system. The ISDF device samples were embedded for hard tissue sections and stained with hematoxylin-eosin and toluidine blue to assess new bone formation. Normally distributed measurement data were expressed as mean±standard deviation( ± s), and independent samples t-test were used for comparisons between groups. Results:In comparison to the sham operation group, the decompression group exhibited a statistically significant increase in intervertebral mobility, with an average of 61.6% in anterior flexion, 44.7% in posterior extension, 65.0% in left lateral flexion, 49.6% in right lateral flexion, 83.8% in left rotation, and 64.2% in right rotation ( P<0.05). In comparison to the decompression group, the ISDF fixed decompression group exhibited a statistically significant decrease in intervertebral mobility, with an average of 40.0% in anterior flexion, 21.3% in posterior extension, 31.7% in left lateral flexion, 22.3% in right lateral flexion, 28.7% in left rotation, and 35.3% in right rotation ( P<0.05). Well-defined bone tissue can be observed in the histological images of ISDF fixed decompression group samples after 6 months. In the histological part, toluidine blue staining showed extensive new bone formation. The hyperchromatic osteoblasts cells and density bone tissue can be observed in hematoxylin-eosin staining slides. Conclusions:The implantation of ISDF provide the necessary stabilization for promoting fusion. The osteogenesis that occurs within graft-bed site of the ISDF device offers the possibility of interspinous fusion.

Objective To explore the characteristics of blood pressure in the elderly patients with hypertensive cerebral small vessel disease(CSVD)and their correlation with traditional Chinese medicine(TCM)syndrome types.Methods A retrospective analysis was conducted in 189 elderly patients with essential hypertension.With reference to the presence or absence of CSVD,the patients were divided into CSVD group(87 cases)and non-CSVD group(102 cases).The blood pressure related parameters and clinical data obtained by four diagnostic methods of TCM in the two groups were collected,and then the characteristics of blood pressure and their correlation with TCM syndromes were analyzed with statistical methods.Results(1)CSVD group had higher values than non-CSVD group in the ambulatory blood pressure parameters of 24-hour systolic blood pressure(24hSBP),24-hour diastolic blood pressure(24hDBP),daytime systolic blood pressure(DSBP),daytime diastolic blood pressure(DDBP),nighttime systolic blood pressure(NSBP),nighttime diastolic blood pressure(NDBP),24-hour pulse pressure(24hPP),daytime pulse pressure(DPP),nighttime pulse pressure(NPP),maximum SBP,morning SBP,daytime SBP load and nighttime SBP load(P＜0.01).(2)The analysis of blood pressure variability showed that the mean value of nighttime SBP standard deviation(NSSD)in CSVD group was higher than that in the non-CSVD group(P＜0.01).(3)The analysis of circadian rhythm of blood pressure showed that there was significant difference in the comparison of circadian rhythm of ambulatory blood pressure between the two groups(P＜0.05):non-CSVD group was predominated by non-dipper type blood pressure(50 cases,49.02%)and dipper type blood pressure(31 cases,30.39%),and CSVD group was predominated by non-dipper type blood pressure(38 cases,43.68%)and super-dipper type blood pressure(31 cases,35.63%).(4)Logistic regression analysis showed that 24hSBP(OR=1.296,95%CI:1.112-1.511),maximum SBP(OR=1.074,95%CI:1.006-1.146),morning SBP(OR=1.064,95%CI:1.013-1.118),abnormal circadian rhythm of blood pressure(OR=3.736,95%CI:1.663-8.390)were the influence factors of CSVD(P＜0.05 or P＜0.01).(5)The analysis of the distribution of TCM syndrome types showed that non-CSVD group was dominated by accumulation of excess phlegm-damp syndrome(58.82%)and yin deficiency and yang hyperactivity syndrome(21.57%),and CSVD group was dominated by yin deficiency and yang hyperactivity syndrome(51.72%)and accumulation of excess phlegm-damp syndrome(21.84%).(6)The analysis of blood pressure in patients with various syndrome types showed that the DPP of patients with accumulation of excess phlegm-damp syndrome in the CSVD group was significantly higher than that in the non-CSVD group(P＜0.01),and the 24hDBP and NDBP of patients with yin deficiency and yang hyperactivity syndrome in the CSVD group were significantly higher than those in the non-CSVD group(P＜0.01).Conclusion It is indicated that 24hSBP,maximum SBP,elevated morning SBP,and abnormal blood pressure circadian rhythms may be the important risk factors for the hypertensive CSVD in the elderly.Elderly hypertensive patients with accumulation of excess phlegm-damp syndrome should pay more attention to the mean daytime pulse pressure,and elderly hypertensive patients with yin deficiency and yang hyperactivity syndrome should pay more attention to monitoring DBP.The dynamic observation and early control of the blood pressure is helpful for the prevention and treatment of CSVD in the elderly patients with hypertension.

Ferroptosis is a recently discovered form of cell death,which is characterized by abnormal intracellular i-ron ion accumulation and lethal lipid peroxidation.The regulatory cell death is closely related to iron metabolism,a-mino acid metabolism,lipid metabolism and other metabolic pathways.Atherosclerosis underlies the pathogenesis of a variety of cardiovascular diseases.Recent studies have shown that in addition to classical death pathways such as apoptosis,necrosis and autophagy,ferroptosis is also involved in the occurrence and development of atherosclerosis.This article elaborates the mechanism of ferroptosis and its effect on atherosclerotic lesion-related cells and factors.

The current situation of deep learning applied to single-and multi-lead ECG detection of arrhythmia was reviewed.The problems of deep learning during the application in generalization,interpretability and time complexity were analyzed,and the countermeasures were put forward accordingly.It's pointed out deep learning would be applied widely in arrhythmia ECG detection with the development of the algorithm,dataset and hardware.[Chinese Medical Equipment Journal,2024,45(2):105-112]

Objective To design a novel oxygenator to solve the existing problems of extracorporeal membrane oxygenation(ECMO)machine in high transmembrane pressure difference,low efficiency of blood oxygen exchange and susceptibility to thrombosis.Methods The main body of the oxygenator vascular access flow field was gifted with a flat cylindrical shape.The topology of the vascular access was modeled in three dimensions,and the whole flow field was cut into a blood inlet section,an inlet buffer,a heat exchange zone,a blood oxygen exchange zone,an outlet buffer and a blood outlet section.The oxygenator was compared with Quadrox oxygenator by means of ANSYS FLUENT-based simulation and prototype experiments.Results Simulation calculations showed the oxygenator designed was comparable to the clinically used ones in general,and gained advantages in transmembrane pressure difference,blood oxygen exchange and flow uniformity.Experimental results indicated that the oxygenator behaved better than Quadrox oxygenator in transmembrane pressure difference and blood oxygen exchange.Conclusion The oxygenator has advantages in transmem-brane pressure difference,temperature change,blood oxygen ex-change and low probability of thrombosis.[Chinese Medical Equipment Journal,2024,45(3):23-28]