BACKGROUND The pedicle screw technique is widely employed for vertebral body fixation in the treatment of spinal disorders.However,traditional screw placement methods require the dissection of paraspinal muscles and t...BACKGROUND The pedicle screw technique is widely employed for vertebral body fixation in the treatment of spinal disorders.However,traditional screw placement methods require the dissection of paraspinal muscles and the insertion of pedicle screws at specific transverse section angles(TSA).Larger TSA angles require more force to pull the muscle tissue,which can increase the risk of surgical trauma and ischemic injury to the lumbar muscles.AIM To study the feasibility of zero-degree TSA vertical pedicle screw technique in the lumbosacral segment.METHODS Finite element models of vertebral bodies and pedicle screw-rod systems were established for the L4-S1 spinal segments.A standard axial load of 500 N and a rotational torque of 10 N/m were applied.Simulated screw pull-out experiment was conducted to observe pedicle screw resistance to pull-out,maximum stress,load-displacement ratio,maximum stress in vertebral bodies,load-displacement ratio in vertebral bodies,and the stress distribution in pedicle screws and vertebral bodies.Differences between the 0-degree and 17-degree TSA were compared.RESULTS At 0-degree TSA,the screw pull-out force decreased by 11.35%compared to that at 17-degree TSA(P<0.05).At 0-degree and 17-degree TSA,the stress range in the screw-rod system was 335.1-657.5 MPa and 242.8-648.5 MPa,separately,which were below the fracture threshold for the screw-rod system(924 MPa).At 0-degree and 17-degree TSA,the stress range in the vertebral bodies was 68.45-78.91 MPa and 39.08-72.73 MPa,separately,which were below the typical bone yield stress range for vertebral bodies(110-125 MPa).At 0-degree TSA,the load-displacement ratio for the vertebral bodies and pedicle screws was slightly lower compared to that at 17-degree TSA,indicating slightly lower stability(P<0.05).CONCLUSION The safety and stability of 0-degree TSA are slightly lower,but the risks of screw-rod system fracture,vertebral body fracture,and rupture are within acceptable limits.展开更多
AIM:To determine the efficacy and safety of pedicled conjunctival lacrimal duct reconstruction in the treatment of severe obstruction of superior and inferior lacrimal canaliculi with conjunctivochalasis.METHODS:This ...AIM:To determine the efficacy and safety of pedicled conjunctival lacrimal duct reconstruction in the treatment of severe obstruction of superior and inferior lacrimal canaliculi with conjunctivochalasis.METHODS:This study was per formed as a retrospective analysis of patients who received conjunctival dacryocystorhinostomy with pedicled conjunctival flap reconstruction combined with tube intubation due to severe superior and inferior lacrimal canalicular obstruction with conjunctivochalasis from January 2019 to October 2019.The clinical data included the degree of preoperative epiphora and postoperative relief,preoperative examination of lacrimal duct computed tomography and ultrasound biomicroscopy,postoperative evaluation of lacrimal duct function by chloramphenicol taste and fluorescein dye disappearance test,etc.Syringing was carried out to determine the reconstruction and patency of the lacrimal duct.RESULTS:All 9 patients(9 eyes)had severe canalicular obstruction with conjunctivochalasis.The patients included 4 males and 5 females aged between 47–65y with an average age of 52.2±6.7y.At 3mo follow-up,the tube was removed and the patients were followed for a further 3mo.After tube removal,6 patients showed no epiphora.These patients also had positive chloramphenicol tastes and normal fluorescein dye disappearance test results.Two patientshad epiphora.Also,syringing showed partial patency of the reconstructed lacrimal duct.One patient had no improvement in epiphora with negative chloramphenicol taste and fluorescein dye disappearance test results and obstruction of the reconstructed lacrimal duct.The total effective rate of the operation was 8/9,with no serious complications.CONCLUSION:Pedicled conjunctival lacrimal duct reconstruction conjunctival dacryocystorhinostomy is safe and effective for superior and inferior canalicular obstruction with conjunctivochalasis.展开更多
Background: Off-pump coronary artery bypass grafting (OPCAB) is a surgical procedure that has gained popularity due to its potential benefits over traditional coronary artery bypass grafting, including reduced morbidi...Background: Off-pump coronary artery bypass grafting (OPCAB) is a surgical procedure that has gained popularity due to its potential benefits over traditional coronary artery bypass grafting, including reduced morbidity and mortality. However, sternal wound complication (SWC) remains challenging following the procedure. The technique of left internal mammary artery (LIMA) harvesting has been shown to impact the incidence of SWC. This study aimed to compare the incidence of SWC between two techniques of LIMA harvesting, i.e., skeletonized and pedicled. Methods: The study was conducted at the Department of Cardiac Surgery, Bangabandhu Sheikh Mujib Medical University, and included 60 patients who underwent OPCAB. The patients were divided into two groups of 30 each based on the technique of LIMA harvesting used, i.e., skeletonized (group A) or pedicled (group B). The postoperative ICU care was given to each patient as per the protocol. The statistical analysis was conducted using the SPSS version 26.0 for Windows software. Results: The results showed that 5 (8.33%) patients developed SWC, with 1 (1.67%) patient in group A and 4 (6.66%) patients in group B. However, the occurrence of SWC was not statistically significant between the two groups (p = 0.35). The mean age, gender distribution, and comorbidities such as hypertension, diabetes, dyslipidemia, and anemia were also not statistically significant between the two groups. The number of smokers was statistically significant between the two groups (p = 0.03), and the occurrence of SWC was found to be higher in smoker patients in group B (p = 0.04). Preoperative and postoperative parameters such as duration of operation, duration of mechanical ventilation, duration of chest drains, duration of the central venous line, and amount of postoperative mediastinal bleeding were also not statistically significant between the two groups. The distribution of wound complications, duration of ICU stays, and hospital stay between the two groups was also not statistically significant. Conclusion: In conclusion, this study found that the incidence of SWC was less in skeletonized LIMA harvesting than in pedicled LIMA harvesting after OPCAB. However, this finding was not statistically significant. Further studies with larger sample sizes may be needed to confirm these results and determine the appropriate technique of LIMA harvesting to decrease the incidence of SWC after OPCAB.展开更多
基金the institutional review board of Mingzhou Hospital of Ningbo(No.202208501).
文摘BACKGROUND The pedicle screw technique is widely employed for vertebral body fixation in the treatment of spinal disorders.However,traditional screw placement methods require the dissection of paraspinal muscles and the insertion of pedicle screws at specific transverse section angles(TSA).Larger TSA angles require more force to pull the muscle tissue,which can increase the risk of surgical trauma and ischemic injury to the lumbar muscles.AIM To study the feasibility of zero-degree TSA vertical pedicle screw technique in the lumbosacral segment.METHODS Finite element models of vertebral bodies and pedicle screw-rod systems were established for the L4-S1 spinal segments.A standard axial load of 500 N and a rotational torque of 10 N/m were applied.Simulated screw pull-out experiment was conducted to observe pedicle screw resistance to pull-out,maximum stress,load-displacement ratio,maximum stress in vertebral bodies,load-displacement ratio in vertebral bodies,and the stress distribution in pedicle screws and vertebral bodies.Differences between the 0-degree and 17-degree TSA were compared.RESULTS At 0-degree TSA,the screw pull-out force decreased by 11.35%compared to that at 17-degree TSA(P<0.05).At 0-degree and 17-degree TSA,the stress range in the screw-rod system was 335.1-657.5 MPa and 242.8-648.5 MPa,separately,which were below the fracture threshold for the screw-rod system(924 MPa).At 0-degree and 17-degree TSA,the stress range in the vertebral bodies was 68.45-78.91 MPa and 39.08-72.73 MPa,separately,which were below the typical bone yield stress range for vertebral bodies(110-125 MPa).At 0-degree TSA,the load-displacement ratio for the vertebral bodies and pedicle screws was slightly lower compared to that at 17-degree TSA,indicating slightly lower stability(P<0.05).CONCLUSION The safety and stability of 0-degree TSA are slightly lower,but the risks of screw-rod system fracture,vertebral body fracture,and rupture are within acceptable limits.
基金Supported by Dalian Medical Science Research Project (No.1811048)。
文摘AIM:To determine the efficacy and safety of pedicled conjunctival lacrimal duct reconstruction in the treatment of severe obstruction of superior and inferior lacrimal canaliculi with conjunctivochalasis.METHODS:This study was per formed as a retrospective analysis of patients who received conjunctival dacryocystorhinostomy with pedicled conjunctival flap reconstruction combined with tube intubation due to severe superior and inferior lacrimal canalicular obstruction with conjunctivochalasis from January 2019 to October 2019.The clinical data included the degree of preoperative epiphora and postoperative relief,preoperative examination of lacrimal duct computed tomography and ultrasound biomicroscopy,postoperative evaluation of lacrimal duct function by chloramphenicol taste and fluorescein dye disappearance test,etc.Syringing was carried out to determine the reconstruction and patency of the lacrimal duct.RESULTS:All 9 patients(9 eyes)had severe canalicular obstruction with conjunctivochalasis.The patients included 4 males and 5 females aged between 47–65y with an average age of 52.2±6.7y.At 3mo follow-up,the tube was removed and the patients were followed for a further 3mo.After tube removal,6 patients showed no epiphora.These patients also had positive chloramphenicol tastes and normal fluorescein dye disappearance test results.Two patientshad epiphora.Also,syringing showed partial patency of the reconstructed lacrimal duct.One patient had no improvement in epiphora with negative chloramphenicol taste and fluorescein dye disappearance test results and obstruction of the reconstructed lacrimal duct.The total effective rate of the operation was 8/9,with no serious complications.CONCLUSION:Pedicled conjunctival lacrimal duct reconstruction conjunctival dacryocystorhinostomy is safe and effective for superior and inferior canalicular obstruction with conjunctivochalasis.
文摘Background: Off-pump coronary artery bypass grafting (OPCAB) is a surgical procedure that has gained popularity due to its potential benefits over traditional coronary artery bypass grafting, including reduced morbidity and mortality. However, sternal wound complication (SWC) remains challenging following the procedure. The technique of left internal mammary artery (LIMA) harvesting has been shown to impact the incidence of SWC. This study aimed to compare the incidence of SWC between two techniques of LIMA harvesting, i.e., skeletonized and pedicled. Methods: The study was conducted at the Department of Cardiac Surgery, Bangabandhu Sheikh Mujib Medical University, and included 60 patients who underwent OPCAB. The patients were divided into two groups of 30 each based on the technique of LIMA harvesting used, i.e., skeletonized (group A) or pedicled (group B). The postoperative ICU care was given to each patient as per the protocol. The statistical analysis was conducted using the SPSS version 26.0 for Windows software. Results: The results showed that 5 (8.33%) patients developed SWC, with 1 (1.67%) patient in group A and 4 (6.66%) patients in group B. However, the occurrence of SWC was not statistically significant between the two groups (p = 0.35). The mean age, gender distribution, and comorbidities such as hypertension, diabetes, dyslipidemia, and anemia were also not statistically significant between the two groups. The number of smokers was statistically significant between the two groups (p = 0.03), and the occurrence of SWC was found to be higher in smoker patients in group B (p = 0.04). Preoperative and postoperative parameters such as duration of operation, duration of mechanical ventilation, duration of chest drains, duration of the central venous line, and amount of postoperative mediastinal bleeding were also not statistically significant between the two groups. The distribution of wound complications, duration of ICU stays, and hospital stay between the two groups was also not statistically significant. Conclusion: In conclusion, this study found that the incidence of SWC was less in skeletonized LIMA harvesting than in pedicled LIMA harvesting after OPCAB. However, this finding was not statistically significant. Further studies with larger sample sizes may be needed to confirm these results and determine the appropriate technique of LIMA harvesting to decrease the incidence of SWC after OPCAB.
