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1.
《Radiography》2022,28(2):553-559
IntroductionCOVID-19 is a highly contagious viral disease declared a global pandemic in March 2020. Throughout the pandemic, radiography students have been working in hospitals on the frontline. The review aimed to search for evidence of the impact COVID-19 has had on diagnostic radiography students and consider whether additional support and learning needs to be implemented.MethodsA literature search strategy applied keywords, BOOLEAN search operators, and eligibility criteria on PubMed, Medline, and Google Scholar databases. Cormack's (2000) critique framework was chosen to methodologically appraise the mixed-method studies to evaluate the quality, validity and rigour.ResultsThe search decisions were displayed in a PRISMA flowchart to evidence the process to identify the found articles comprised of two surveys, two semi-structured interviews and one case study. The findings identified common and reoccurring themes of personal protective equipment, mental wellbeing, accommodation and travel, assessments and learning, and transitioning to registration.ConclusionThe literature suggests that students felt positive impacts of the pandemic, such as being prepared for registration. However, negative effects included the fear of contracting the virus, anxieties of working with ill patients, impracticalities of accommodation and travel during clinical placement, and the adaption to online learning.Implications for practiceClinical staff and universities need to work together to ensure students are mentally and physically supported during the pandemic. Regular meetings and agreed channels of communication with students will allow any issues to be brought to attention and addressed. In addition, employers should recognise that newly qualified radiographers will need extra support. 相似文献
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BACKGROUNDFour-level lumbar spondylolysis is extremely rare. So far, only 1 case has been reported in the literature. CASE SUMMARYA 19-year-old man presented with severe back pain irresponsive to conservative therapies for 2 years. Lumbar radiographs and two-dimensional computed tomography scan showed four segment lumbar spondylolysis on both sides of L2-L5. Lumbar magnetic resonance imaging showed normal signal in all lumbar discs. Because daily activities were severely limited, surgery was recommended for the case. The patient underwent four-level bilateral isthmic repair at L2-L5. During surgery, L2-L5 isthmi were curetted bilaterally, freshened, and then grafted with autologous iliac bone that was bridged and compressed with a pedicular screw connected to a sub-laminar hook by a short rod. The symptoms of back pain almost disappeared. He has been followed-up for 96 mo, and his symptoms have never recurred. Fusion was found in all repaired isthmi 14 mo after surgery according to evaluation of lumbar radiography and computed tomography scan.CONCLUSIONWe report here 1 case of four-level lumbar spondylolysis that was treated successfully with direct isthmic repair. 相似文献
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目的 探讨神经外科手术机器人在人体腰椎模型进行椎弓根螺钉置入的精准性。方法 利用O型臂影像系统对模型进行正侧位扫描,并三维重建,获取3D-CT数据,传入手术机器人系统,规划椎弓根螺钉的最佳进钉点和进钉方向。手术机器人系统利用3D-CT数据自动注册后,置入椎弓根螺钉。应用置钉前后的3D融合图像,按照Gertzbein-Robbins分级评估置钉的准确性。结果 共置入39枚椎弓根螺钉,其中37枚螺钉完全位于椎弓根内,2枚螺钉突破椎弓根的内壁2 mm以内。螺钉与原规划钉道的平均偏移距离为(1.45±0.67)mm。螺钉在进钉点的滑移方向:内下方16枚(41.03%),外上方6枚(15.38%),下方6枚(15.38%),外下方5枚(12.82%),内上方4枚(10.26%),内方1枚(2.56%),上方1枚(2.56%)。结论 神经外科手术机器人置入椎弓根螺钉具有较高的精准性。 相似文献
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Objective
Symptomatic distal interlocking screws in retrograde femoral nailing are common due the difficulties of imaging the trapezoidal femur. Screws appearing to have appropriate length on imaging may possibly be prominent, creating symptoms. Screw trajectory may influence the degree of this radiographic error. We hypothesize that external rotation of screw trajectory will increase measurement error of screw length.Design
Retrospective.Setting
Urban Level I Tertiary Trauma Center.Participants
283 patients with Computer Tomography (CT) scans of the native knee were retrospectively identified. Simulation was done of the trajectory of an interlock at 20?mm and 40?mm proximal to the nail entry point, which represent common screw positions associated/not associated respectively, with removal. The distance between the radiographic medial cortex and the tip of the transverse screw was calculated (D). The angle (Ψ) between the transverse trajectory and a modified trajectory aimed at the most medial cortex to avoid radiographic measurement error was calculated. Geometric modeling was utilized to calculate the measurement error (D) in the event of accidental external rotation. The angle of the medial slope was also measured (Θ).Intervention
Review of CT imaging of normal distal femora.Main Outcome Measurements
CT measurements of distal femora.Results
The mean distance (D) at 20/40?mm was 4.21 [95%CI 4.02–4.402] and 2.03?mm [95%CI 1.78–2.83], respectively (p?<?0.0001). The mean angle (Ψ) between the transverse and modified trajectory at 20/40?mm was 12° [95%CI 11.5–12.5] and 9.60° [95%CI 9–10.2], respectively (p?<?0.0001). External rotation by a similar amount nearly triples the measured difference (D). The measured medial slope was significantly increased as screws were placed more proximal (Θ20 mm 46.5 vs Θ40 mm: 48.7?°, p?<?0.00001).Conclusion
The distance between the perceived medial cortex and the tip of the most transverse screw is 4.21?mm and could account for painfully prominent screws. In more proximal screws this distance is decreased. Internal rotation of the screw trajectory 12° can reduce this distance (D), which has implications in nail design. External rotation, amplifies this difference nearly three-fold. Surgeons should avoid external rotation of the aiming arm to prevent prominent screws. 相似文献6.
J. Hachleitner C. Brandtner A. Gaggl M. Kopp G. Fastner G. Moser S. Roesch 《International journal of oral and maxillofacial surgery》2019,48(4):468-474
The purpose of this study was to describe a newly developed procedure for temporary mandibulotomy and subsequent osteosynthesis. Clinical outcomes were evaluated, including complications and the impact on postoperative treatment, particularly postoperative radiotherapy. Twenty-four patients underwent temporary mandibulotomies for the surgical resection of malignancies located in the posterior oral or oropharyngeal region. All were treated with postoperative radiotherapy. An angulated median mandibulotomy was followed by osteosynthesis with three anchor screws directed towards the inferior aspect of the mandible. Anchor screws are modified conventional lag screws that include an additional biconcave washer. This modification prevents the screw heads from cracking into the cancellous bone during tightening, improving their biomechanical qualities considerably. Insertion of screws at any angle to the bony surface therefore becomes possible, which is a precondition for this technique. Minor complications occurred in two patients in the early postoperative period. However, complications causing bony non-union, leading to postponed postoperative radiotherapy were not noted in this cohort. 相似文献
7.
《Clinical neurophysiology》2019,130(4):573-581
ObjectiveWe describe a stimulus-evoked EMG approach to minimize false negative results in detecting pedicle breaches during lumbosacral spinal instrumentation.MethodsIn 36 patients receiving 176 lumbosacral pedicle screws, EMG threshold to nerve root activation was determined using a focal probe inserted into the pilot hole at a depth, customized to the individual patients, suitable to position the stimulating tip at the point closest to the tested nerve root. Threshold to screw stimulation was also determined.ResultsMean EMG thresholds in 161 correctly fashioned pedicle instrumentations were 7.5 mA ± 2.46 after focal hole stimulation and 21.8 mA ± 6.8 after screw stimulation. Direct comparison between both thresholds in individual pedicles showed that screw stimulation was always biased by an unpredictable leakage of the stimulating current ranging from 10 to 90%. False negative results were never observed with hole stimulation but this was not true with screw stimulation.ConclusionsFocal hole stimulation, unlike screw stimulation, approaches absolute EMG threshold as shown by the lower normal limit (2.6 mA; p < 0.05) that borders the upper limit of threshold to direct activation of the exposed root.SignificanceThe technique provides an early warning of a possible pedicle breakthrough before insertion of the more harmful, larger and threaded screw. 相似文献
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