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21.

Objective

It is clinically important for pedicle screws to be placed quickly and accurately. Misplacement of pedicle screws results in various complications. However, the incidence of complications varies greatly due to the different professional titles of physicians and surgical experience. Therefore, physicians must minimize pedicle screw dislocation. This study aims to compare the three nail placement methods in this study, and explore which method is the best for determining the anatomical landmarks and vertical trajectories.

Methods

This study involved 70 patients with moderate idiopathic scoliosis who had undergone deformity correction surgery between 2018 and 2021. Two spine surgeons used three techniques (preoperative computed tomography scan [CTS], visual inspection-X-freehand [XFH], and intraoperative detection [ID] of anatomical landmarks) to locate pedicle screws. The techniques used include visual inspection for 287 screws in 21 patients, preoperative planning for 346 screws in 26 patients, and intraoperative probing for 309 screws in 23 patients. Observers assessed screw conditions based on intraoperative CT scans (Grade A, B, C, D).

Results

There were no significant differences between the three groups in terms of age, sex, and degree of deformity. We found that 68.64% of screws in the XFH group, 67.63% in the CTS group, and 77.99% in the ID group were placed within the pedicle margins (grade A). On the other hand, 6.27% of screws in the XFH group, 4.33% in the CTS group, and 6.15% in the ID group were considered misplaced (grades C and D). The results show that the total amount of upper thoracic pedicle screws was fewer, meanwhile their placement accuracy was lower. The three methods used in this study had similar accuracy in intermediate physicians (P > 0.05). Compared with intermediate physicians, the placement accuracy of three techniques in senior physicians was higher. The intraoperative detection group was better than the other two groups in the good rate and accuracy of nail placement (P < 0.05).

Conclusion

Intraoperative common anatomical landmarks and vertical trajectories were beneficial to patients with moderate idiopathic scoliosis undergoing surgery. It is an optimal method for clinical application.  相似文献   
22.

Objective

Laminectomy has been widely used for intraspinal tumor resection. However, the tilted spinous process and narrow lateral laminae of the thoracic spine along with the hypertrophic ligamentum flavum of the lumbar spine pose certain problems for the laminae removal of the traditional laminectomy. We improved the laminectomy method with ultrasonic osteotome to treat thoracolumbar tumors and assessed its safety and superiority.

Methods

A retrospective analysis was performed in 86 patients with thoracolumbar (T4–L5) spinal tumors treated by resection, including 44 with the lamina removed using the traditional method and 42 with the lamina removed using the bone-to-bone ligament preserving (BLP) laminoplasty, which preserves the posterior ligament complex. Age, sex, and tumor size, location, and depth were compared between the two groups. The length of incision and bone window, time to remove the vertebral lamina, and epidural effusion volume were recorded at 2 weeks after surgery in the two groups. Postoperative reexamination by magnetic resonance imaging (MRI) at 2 weeks and 3 months after surgery was compared with preoperative MRI to assess the change in vertebral lamina displacement.

Results

There were no statistical differences in age, sex, and tumor size, depth, or location between the two groups. The BLP laminectomy did not increase the risk of dural, spinal cord, or nerve injuries. The difference between the incision and tumor length, as well as the difference between the bone window and tumor length in the BLP laminectomy group, were smaller than those in the traditional laminectomy group, and the BLP laminectomy took less time compared to that of the traditional laminectomy (p < 0.05). There was no significant difference in the volume of epidural effusion between the two groups at 2 weeks postoperatively, or in the displacement of the returned vertebral plate observed in sagittal and axial positions. The same was true for the displacement at 3 months postoperatively in the axial position. However, the sagittal displacement in the BLP laminectomy group was smaller than that in the traditional laminectomy group (p < 0.05).

Conclusions

The BLP laminectomy is safe for the resection of thoracolumbar spinal canal tumors. It is less traumatic and faster, with less displacement of the returned lamina, resulting in a stable repair of the spine.  相似文献   
23.

Objective

Multi-segmental thoracolumbar fracture (MSF) generally refers to fractures occurring in two or more segments of the thoracolumbar spine. With the development of minimally invasive concept, there is little research on its application in the field of MSF. The purpose of this study is to compare two minimally invasive surgical techniques and determine which one is more suitable for treating patients with neurologically intact MSF.

Methods

We retrospectively analyzed the clinical data of 49 MSF patients with intact nerves who were admitted from January 2017 to February 2019. Among them, 25 cases underwent percutaneous pedicle screw fixation (PPSF), and 24 cases underwent Wiltse approach pedicle screw fixation (WAPSF). The operation time, number of fixed segments, blood loss, length of incision, postoperative ambulation time, accuracy of pedicle screw placement, facet joint violation (FJV), number of C-arm exposures, as well as pre- and postoperative visual analogue scale (VAS), Oswestry disability index (ODI), local Cobb's angle (LCA), and percentage of anterior vertebral body height (PAVBH) were recorded for both groups. Paired sample t-test was used for intra-group comparison before and after surgery while independent sample t-test was used for inter-group comparison.

Results

The differences in the number of fixed segments, intraoperative bleeding, postoperative bed time, accuracy rate of pedicle screw placement, VAS, and ODI between the two groups were not statistically significant (p > 0.05). However, the operative time and total surgical incision length were significantly shorter in the WAPSF group than in the PPSF group (p < 0.05), and the FJV was significantly higher in the PPSF group than in the WAPSF group (p < 0.05). Also, the PPSF group received more intraoperative fluoroscopy (p < 0.05). The result of LCA and PAVBH in the WAPSF group were significantly better than in the PPSF group (p < 0.05).

Conclusions

Both PPSF and WAPSF were found to be safe and effective in the treatment of MSF without neurological deficits through our study. However, considering radiation exposure, FJV, vertebral height restoration, correction of kyphosis, and learning curve, WAPSF may be a better choice for neurologically intact MSF.  相似文献   
24.
Chronic wounds have become one of the major issues in medicine today, the treatments for which include dressing changes, negative pressure wound therapy, hyperbaric oxygen, light irradiation, surgery and so forth. Nevertheless, the application of diode lasers in chronic wounds has rarely been reported. This retrospective cohort study aimed to evaluate the therapeutic effect of diode laser (810 nm) irradiation on chronic wounds. Eighty-nine patients were enrolled in the study. The control group (41 patients) received traditional dressing change therapy, while the diode laser treatment group (48 patients) were patients received additional treatment with diode laser (810 nm) irradiation for 10 min at each dressing change. Wound healing time was compared between two groups, while the pain relief index was creatively introduced to evaluate the effect of relieving wound pain, which was calculated by the difference in pain scores between the first and last dressing changes divided by the number of treatment days. The wound healing time of the diode laser treatment group was 22.71 ± 8.99 days, which was significantly shorter than that of the control group (37.44 ± 23.42 days). The pain relief index of the diode laser treatment group was 0.081 ± 0.055, which was significantly increased compared with that of the control group (0.057 ± 0.033). Our findings suggest that diode laser irradiation has the potential to promote healing in chronic wounds and relieve wound pain.  相似文献   
25.
26.
Abstract: Background:  Patients with chronic renal failure (CRF) are at high risk of renal osteodystrophy. Our study aimed to identify predictors of bone mass and cumulative fracture rate at the time of renal transplantation (RTx). This is important since the patients experience further substantial bone loss the first month post-transplant.
Material and methods:  Altogether 133 renal transplant patients were examined for bone mineral density (BMD) using dual-energy X-ray absorptiometry shortly after RTx.
Results:  The patients' Z -scores were significantly lower at the time of RTx compared to the reference population (p < 0.05), 32% were osteopenic and 11% had osteoporosis. Independent predictors of low bone mass were age (p < 0.001), female sex (p < 0.001), intact parathyroid hormone (iPTH) level (p < 0.001), former transplantation (p = 0.001) and time on hemodialysis (HD) (p = 0.005). Body mass index (BMI) (p < 0.001) and physical activity (p = 0.027) were associated with high BMD. Cumulative fracture rate (29%) was associated with physical inactivity (p = 0.003), BMI (p = 0.036) and osteopenia (p < 0.001) at the time of RTx.
Conclusion:  In a representative CRF population, BMD was reduced. Independent predictors of BMD were as for the general population, and uremia associated predictors were time on HD, previous transplantation and serum iPTH level. Fracture rate was high, and physical inactivity had the strongest association with fractures.  相似文献   
27.
28.
Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence.  相似文献   
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