Surgical Management of Lumbar Spinal Canal Stenosis with Instrumentation at the Yaounde Central Hospital: Comparison of Unilateral versus Bilateral Pedicle Screw Fixation Combined with Transforaminal Lumbar Interbody Fusion

Introduction: The choice of adopting unilateral pedicle screw fixation or using bilateral pedicle screw fixation in lumbar spinal stenosis remains controversial. In our context, very few studies have been performed comparing the clinical effectiveness of unilateral versus bilateral fixation in the surgical management of lumbar spinal canal stenosis. Objective: Evaluate the impact on quality of life and clinical efficacy of unilateral spondylodesis compared to bilateral spondylodesis in the surgical management of lumbar spinal canal stenosis at the Yaounde Central Hospital. Methods: This was a retrospective descriptive cross-sectional study for a period of 4 years, from June 2015 to June 2019. It involved all patients operated for lumbar canal stenosis and who underwent spondylodesis or spinal fusion at the neurosurgery department of the Yaounde Central Hospital. Results: A total of 68 participants were recruited during our study period. 32 (47%) of the study population were in the 50 - 60 age group, with a mean age of 56.98 years ranging from 41 to 75 years. Females, housewives and farmers were the most affected. In our study, 72% of patients had unilateral spondylodesis and 28% had bilateral fusion. Preoperatively, 71% of patients had insurmountable pain, refractory to medical treatment. At 3 months postoperatively, 73.7% of patients with bilateral setup had moderate pain compared to 69% of those with unilateral setup. At 6 months postoperatively, 79% of patients with bilateral fusion had mild pain compared to 82% of patients with unilateral setup. At 1 year postoperatively, all patients had mild pain. Preoperatively, 66.2% of patients were unable to walk and 19.1% of patients were bedridden according to the Oswestry score. At 3 months postoperatively, 10.2% of patients with unilateral setup were unable to walk compared to 10.5% of patients with bilateral fixation, while 67.3% of patients with unilateral fixation had moderate disability compared to 52.6% of patients with bilateral fixation. At 6 months postoperatively, 51% of patients with unilateral setup had moderate disability compared to 47.4% of patients with bilateral fixation, while 42.9% of patients with unilateral fixation had mild disability compared to 42.1% of patients with bilateral fixation. At 1 year postoperatively, 81.6% of patients who underwent unilateral fixation had only mild disability compared to 73.7% of patients with bilateral fixation. Conclusion: The assessment of quality of life according to the set-up used shows similar results at 3 months, 6 months and 1 year, with no statistically significant differences. Single-sided pedicle screw fixation combined with transforaminal lumbar interbody fusion or mounting has the advantage of being faster, with less bleeding and is less expensive compared to bilateral fixation.

Cost-effectiveness of patient specific vs conventional instrumentation for total knee arthroplasty:A systematic review and meta-analysis

BACKGROUND Over the past years,patient specific instrumentation(PSI)for total knee arthroplasty(TKA)has been implemented and routinely used.No clear answer has been given on its associated cost and cost-effectiveness when compared to conventional instrumentation(CI)for TKA.AIM To compare the cost and cost-effectiveness of PSI TKA compared to CI TKA.METHODS A literature search was performed in healthcare,economical healthcare,and medical databases(MEDLINE,EMBASE,CINAHL,Web of Science,Cochrane Library,EconLit).It was conducted in April 2021 and again in January 2022.Relevant literature included randomised controlled trials,retrospective studies,prospective studies,observational studies,and case control studies.All studies were assessed on methodological quality.Relevant outcomes included incremental cost-effectiveness ratio,quality-adjusted life years,total costs,imaging costs,production costs,sterilization associated costs,surgery duration costs and readmission rate costs.All eligible studies were assessed for risk of bias.Meta-analysis was performed for outcomes with sufficient data.RESULTS Thirty-two studies were included into the systematic review.Two were included in the metaanalysis.3994 PSI TKAs and 13267 CI TKAs were included in the sample size.The methodological quality of the included studies,based on Consensus on Health Economic Criteria-scores and risk of bias,ranged from average to good.PSI TKA costs less than CI TKA when considering mean operating room time and its associated costs and tray sterilization per patient case.PSI TKA costs more compared to CI TKA when considering imaging and production costs.Considering total costs per patient case,PSI TKA is more expensive in comparison to CI TKA.Meta-analysis comparing total costs for PSI TKA,and CI TKA showed a significant higher cost for PSI TKA.CONCLUSION Cost for PSI and CI TKA can differ when considering distinct aspects of their implementation.Total costs per patient case are increased for PSI TKA when compared to CI TKA.

The CCD instrument background of the SMILE SXI

The ESA and CAS SMILE mission orbit is highly elliptical and will pass through multiple radiation environments.The Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is high.The shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s Van Allen Belts.Therefore,two radiation environments can be approximated based on the shutter door position:open and closed.The instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the SXI were evaluated for the two environments.Due to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two extremes.The results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic Rays(GCRs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar maxima.This is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCRs between the two solar extremes.

Glaucoma surgery experiments using digital microscope-integrated optical coherence tomography and OCT-compatible instruments

There is a certain failure rate in traditional glaucoma surgery because of the lack of depth information in microscope images.In this work,we present a digital microscope-integrated optical coherence tomography(MIOCT)system and several custom-made OCT-compatible instruments for glaucoma surgery.Sixteen ophthalmologists were asked to perform trabeculectomy and canaloplasty on live porcine eyes using the system and instruments.After surgery,a subjective feedback survey about the user experience was taken.The experiment results showed that our system can help surgeons easily locate important tissue structures during surgery.The custom-made instruments also solved the shadowing problem in OCT imaging.Surgeons preferred to use the system in their future practice.

AVEVA Instrumentation Engineer在仪表系统设计中的应用研究

本文分析AVEVA Instrumentation软件功能模块Engineer在仪表系统设计中的应用。重点探讨借助AVEVA Instrumentation软件实现跨专业、跨软件的数据交互开发及仪表专业清单文件、数据表的模板定制。

Metallosis with spinal implant loosening after spinal instrumentation:A case report

BACKGROUND Spinal metallosis is a rare complication following spinal instrumentation whereby an inflammatory response to the metal implants results in the development of granulomatous tissue.CASE SUMMARY We describe the case of a 78-year-old woman who had recurrence of back pain 5 years after lumbar spine posterior decompression and instrumented fusion.Lumbar spine radiographs showed hardware loosening and magnetic resonance imaging showed adjacent segment disease.Revision surgery revealed evidence of metallosis intraoperatively.CONCLUSION Spinal metallosis can present several years after instrumentation.Radiography and computed tomography may demonstrate hardware loosening secondary to metallosis.Blood metal concentrations associated with spinal metallosis have yet to be established.Hence,metallosis is still an intraoperative and histopathological diagnosis.The presence of metallosis after spinal instrumentation likely indicates a more complex underlying problem:Pseudarthrosis,failure to address sagittal balance,infection,and cross-threading of set screws.Hence,identifying metallosis is important,but initiating treatment promptly for symptomatic implant loosening is of greater paramount.

Reform of Teaching Practice of Modern Instrumental Analysis in Biotechnology Programs

Through the online and offline practical reform of the Modern Instrumental Analysis course of biotechnology majors from teaching content,teaching method,teaching demonstration to teaching effect,the traditional single offline lecture is transformed into diversified and interactive modern teaching.The practical reform enriches and optimizes the course content,perfects and improves the course assessment system,and improves the teaching quality.It achieves the student-centered and application-oriented teaching goal,and also provides reference for further cultivating high-quality applied talents.

Development and validation of an instrument to assess knowledge,attitudes,and practices on digital health among nursing officers

Objective:Validation is an important aspect of an instrument,and it ensures the confidence of researchers to employ the instrument in their studies.This study was conducted to develop and validate an instrument to assess knowledge,attitudes,and practices(KAP) on digital health among nurses since digital health capacity is a major concern in health care that needs to be assessed.Methods:We conducted a methodological study to assess the content validity and reliability of the instrument.First,items were generated through a comprehensive literature review and by obtaining an expert opinion.Second,content and face validity were assessed by a panel of 7 experts.Both the item-level content validity index(I-CVI) and the scale-level content validity index(S-CVI) were established.Moreover,test–retest reliability and internal consistency of the instrument were assessed.Data were analyzed using SPSS version 25.Results:The initial pool consisted of 60 items and after obtaining content,face,and construct validity,51 items remained.Items with an I-CVI <0.78 were considered relevant.The S-CVI for relevancy,clarity,ambiguity,and simplicity were 0.93,0.91,0.94,and 0.92,respectively.Five subcomponents were constructed in each knowledge and attitudes domain,and the test–retest reliability test revealed that the instrument has good reliability,showing correlation coefficient values for the KAP domains and the total questionnaire of 0.76,0.98,0.99,and 0.99,respectively.The independent Cronbach's α for all items was 0.76,indicating good internal consistency.Conclusions:The present study established the acceptable validity and ensured the good reliability and internal consistency of the instrument,which can serve as an assessment tool of KAP on digital health among healthcare professionals.

Design of Signal Lamp Filament Monitoring Alarm Instrument

To improve the reliability of the light emitting diode(LED)signal lamp filament current monitoring alarm instrument for metro systems,a new type of hot standby online monitoring apparatus was developed which is based on synchronous transmission data(STD)bus technology.In this system,a double hot standby mode can be achieved by adopting bus arbitration.In addition,to detect the effective value of alternating current which is from 0 to 200 mA in the signal lamp lighting circuit,a precision rectifier signal conditioning circuit and an isolated acquisition circuit were designed.This new type of alarm instrument has high detection accuracy and could meet the functional requirements for metro signal systems after comparing it with some industry products that were applied on the spot.

浅析AVEVA Instrumentation在仪表设计中的应用

设计领域数字化转型是产业数字化的重要方向,各种专业设计软件强大的数据存储和处理能力,可以为制造业数字化转型提供大量的数据源。为了借助各种专业软件实现业务需求及数据需求,需要对各种专业设计软件进行大量的二次开发工作。AVEVA系列软件作为石化行业主流设计软件,对于设计领域的数字化转型尤为重要。本文基于海上石油平台仪表设计的工作流程,从仪表专业设计的角度分析了AVEVA INSTRUMENTION的各个功能模块及其在相关专业间的协同设计应用,重点探讨围绕VEVA INSTRUMENTION各功能模块进行的规则库、属性库、材料目录库等标准数据库的开发,经导航项目测试效果良好,为海洋工程设计领域的数字化转型奠定了良好的基础,也为后续的实际项目应用及二次开发具有一定的借鉴作用。

Current concepts in total knee arthroplasty: Patient specific instrumentation

Patient specific instrumentation(PSI) in total knee arthroplasty(TKA) promises faster operation time(by using less instruments and individual cutting jigs), less blood loss, faster rehabilitation, better implant sizing and accuracy, superior overall outcome, and at the end- less costs. However, as evident for every new development, its superiority remains to be provenover the conventional systems. Whilst dissatisfaction is reported to be eminent in up to 30% of patients having undergone conventional TKA, it is unclear, whether PSI can address to these patients as a suitable option in the future. The author believes that the current evidence does not support superiority of PSI in TKA over conventional systems. However, future long-term level I and II studies might aid to show its cost-effectiveness stating same results, accuracy, and overall outcome with less operation time.

Evaluation of behaviors of earth and rockfill dams during construction and initial impounding using instrumentation data and numerical modeling

In this study,the behavior of Gavoshan dam was evaluated during construction and the first impounding.A two-dimensional（2D） numerical analysis was conducted based on a finite difference method on the largest cross-section of the dam using the results of instrument measurements and back analysis.These evaluations will be completed in the case that back analysis is carried out in order to control the degree of the accuracy and the level of confidence of the measured behavior since each of the measurements could be controlled by comparing it to the result obtained from the numerical model.Following that,by comparing the results of the numerical analysis with the measured values,it is indicated that there is a proper consistency between these two values.Moreover,it was observed that the dam performance was suitable regarding the induced pore water pressure,the pore water pressure ratio r;,settlement,induced stresses,arching degree,and hydraulic fracturing probability during the construction and initial impounding periods.The results demonstrated that the maximum settlement of the core was 238 cm at the end of construction.In the following 6 years after construction（initial impounding and exploitation period）,the accumulative settlement of the dam was 270 cm.It is clear that 88% of the total settlement of the dam took place during dam construction.The reason is that the clay core was smashed in the wet side,i.e.the optimum moisture content.Whereas the average curving ratio was 0.64 during dam construction; at the end of the initial impounding,the maximum amount of curving ratio in the upstream was 0.81,and the minimum（critical） amount in the downstream was 0.52.It was also concluded that this dam is safe in comparison with the behaviors of other similar dams in the world.

Performance evaluation methods and instrumentation for mine ventilation fans

Ventilation fans are one of the most important pieces of equipment in coal mines. Their performance plays an important role in the safety of staff and production. Given the actual requirements of coal mine production,we instituted a research project on the measurement methods of key performance parameters such as wind pressure,amount of ventilation and power. At the end a virtual instrument for mine ventilation fans performance evaluation was developed using a USB interface. The practical performance and analytical results of our experiments show that it is feasible,reliable and effective to use the proposed instrumentation for mine ventilation performance evaluation.

Intra-operative computed tomography guided navigation for pediatric pelvic instrumentation: A technique guide

Pelvic instrumentation for neuromuscular scoliosis has been part of neuromuscular scoliosis surgery since the era of the Luque Galveston construct. Unit Rod(Medtronic Sofamor-Danek, Nashville, TN) instrumentation brought with it the concept of cantilever correction by placing the implants in the pelvis and then gradually bringing the rod to the spine by sequentially tightening the sublaminar wires, with the goal of creating a level pelvis over a straight spine. More recently surgeons have utilized pedicle screw constructs in which the corrective strategies have varied. Challenges with pelvic fixation using iliac screws linked to the spinal rod have led to the development of the S2-alariliac technique(S2 AI) in which the spinal rod connects to the pelvic screw. The screw is placed in the S2 ala, crosses the sacro-iliac joint and into the ilium through a large column of supra-acetabular bone. This column is the same area used for anterior inferior iliac spine external fixation frames used in trauma surgery. S2 AI screw placement can be technically difficult and can require experienced radiology technologists to provide the appropriate views. Additionally, although the technique was originally described being placed via freehand technique with intra-operative flouroscopy, the freehand technique suffers from the anatomic anomalies present in the pelvis in neuromuscular scoliosis. As such, we prefer to place them using intra-operative navigation for all pediatric spinal deformity cases. Below in detail we report our intra-operative technique and an illustrative case example.

ANTERIOR SPINAL FUSION WITH TSRH INSTRUMENTATION FOR SCOLIOSIS

Objective. To introduce a new spinal internal fixation system, Texas Scottish Rite Hospital (TSRH), and to investigate its early clinical outcomes.Methods. The preliminary clinical outcomes of 15 patients with thoracolumbar or lumbar scoliosis treated by anterior spinal fusion with TSRH instrumentation were studied retrospectively. Fourteen patients were diagnosed as idiopathic scoliosis and 1 as neuromuscular scoliosis.Results. Preoperatively, the Cobb's angle on the coronal plane was 55. 8° (range 35° - 78°), and 14° postoperatively, with an average correction of 74. 8 %. The average unfused thoracical curve was 35. 9 ° preoperatively (range 26° - 51°) and 21. 8° (10°-42° ) postoperatively, with 40% correction. The sagittal curve of lumbar was kept physiologically, preoperative 27. 9° and postoperative 25. 7° respectively. The trunk shift was 13.4 mm (5 - 28mm) preoperatively and 3. 5 mm (0-7 mm) postoperatively. The averaged apic vertebra derivation was 47. 8 mm (21 - 69 mm) before operation and 10. 8 mm (3-20 mm) after operation. The distance of C7 to center sacrum vertical line (CSVL) was 19. 5 mm(16 - 42)preoperatively and 11. 3 mm (0-32 mm) postoperatively. The apical vertebra rotation was 3 degree in 15 patients preoperatively, and were improved to normal in 10 patients, 1 degree in 4 patients, and 2 degree in 1 patients postoperatively. None had neurological injury and infection. Only 1 patient complained a cool feeling in the low extremity of concave side, and the symptom vanished at 3-month followed up.Conclusion. If used appropriately, TSRH anterior spinal system is a good treatment for low thoracic or thoracic lumbar scoliosis.

THREE- DIMENSIONAL CORRECTION OF SCOLIOSIS USING TSRH INSTRUMENTATION

Objective. To evaluate the results of TSRH instrumentation in the correction of coronal, sagittal and rotational deformity of scoliosis. Methods. From January 1998 to December 1999, thirty- two consecutive patients (6 males, 26 females) with scoliosis underwent anterior or posterior spinal instrumentation and fusion using TSRH instrumentation. Of these cases, 21 were idiopathic scoliosis and 11 were congenital scoliosis. The average age at surgery was 16.4 years (range, 11～ 45 years). The mean Cobb angle at surgery was 71 .2 (range, 44～ 125 ) in the coronal plane, and 49.2 ( range, 16～ 67 ) in the sagittal plane. Rotational deformity (Nash- Moe) ranged from I to III degree. Preoperative apical translation averaged 4.8 cm (range, 3～ 9 cm). Results. The average follow- up duration was 13.3 months (range, 10～ 24 months).At the final follow- up, the mean Cobb angle in the coronal plane was 26. 6 (range, 10～ 73 ),with a 63.8％ of improvement. Sagittal alignment was well maintained with a mean Cobb angle of 28 ( range, 10～ 45 ). The average correction of rotation of the apical vertebra was I degree. The average apical translation was 1.6 cm (range, 0.5～ 5.0 cm) representing a correction rate of 66,7％ . Complication was noted in two cases with an incidence of 3.1％ , one case had superficial infection and the other one had lower hook dislocation.There was no neurologic deficit and pseudoarthrodesis in this series. Conclusion. TSRH instrumentation is an effective and convenient three- dimensional correction system with a lower rate of complication, which can not only correct the coronal and rotational deformity, but maintain the sagittal alignment as well.

RESEARCH OF A NEW PORTABLE GC INSTRUMENTATION AND ITS APPLICATION IN BIOMEDICAL ENGINEERING

-A Portable gas chromatograPhy (GC) instrument is presented in this paper. In this GC instrument a new gaseous sampling device was used in place of conventional sampling valves.It has no quantitative tube or movable components in the sample Path. The sampling size si determined by time with a high precision,which is not sensitive to the sample temperature and pressure.Especially,the sample can not only inject into the column head,but also the carrier gas blow the column reversely and clean it.The portable GC instrument based on the sampling device can be used in enviromental and biomedical monitoring.

A Systematic Approach for Instrumentation of a Mechatronic System

This paper deals with instrumenting a mechatronic system,through the incorporation of suitable sensors,actuators,and other required hardware.Sensors(e.g.,semiconductor strain gauges,tachometers,RTD temperature sensors,cameras,piezoelectric accelerometers)are needed to measure(sense)unknown signals and parameters of a system and its environment.The information acquired in this manner is useful in operating or controlling the system,and also in process monitoring;experimental modeling(i.e.,model identification);product testing and qualification;product quality assessment;fault prediction,detection and diagnosis;warning generation;surveillance,and so on.Actuators(e.g.,stepper motors,solenoids,dc motors,hydraulic rams,pumps,heaters/coolers)are needed to"drive"a plant.Control actuators(e.g.,control valves)perform control actions,and in particular they drive control devices.Micro-electromechanical systems(MEMS)use microminiature sensors and actuators.MEMS sensors commonly use piezoelectric,capacitive,electromagnetic and piezoresistive principles.MEMS devices provide the benefits of small size and light weight(negligible loading errors),high speed(high bandwidth),and convenient mass-production(low cost).The process of instrumentation involves the identification of proper sensors,actuators,controllers,signal modification/interface hardware,and software with respect to their functions,operation,parameters,ratings,interaction with each other,so as to achieve the performance requirements of the overall system,and interfacing/integration/tuning of the selected devices into the system,for a given application.This paper presents the key steps of instrumenting a mechatronic system,in a somewhat general and systematic manner.Examples are described to illustrate several key procedures of instrumentation.

Patient-specific instrumentation in total ankle arthroplasty

The recent increase in the adoption of total ankle arthroplasty(TAA)reflects the improvements in implant designs and surgical techniques,including the use of preoperative navigation system and patient-specific instrumentation(PSI),such as custom-made cutting guides.Cutting guides are customized with respect to each patient's anatomy based on preoperative ankle computed tomography scans,and they drive the saw intra-operatively to improve the accuracy of bone resection and implant positioning.Despite some promising results,the main queries in the literature are whether PSI improves the reliability of achieving neutral ankle alignment and more accurate implant sizing,whether it is actually superior over standard techniques,and whether it is cost effective.Moreover,the advantages of PSI in clinical outcomes are still theoretical because the current literature does not allow to confirm its superiority.The purpose of this review article is therefore to assess the current literature on PSI in TAA with regard to current implants with PSI,templating and preoperative planning strategies,alignment and sizing,clinical outcomes,cost analysis,and comparison with standard techniques.

Magnetically controlled growing instrumentation for early onset scoliosis: Caution needed when interpreting the literature

BACKGROUND Magnetically controlled growing rods(MCGR) are a novel treatment option for early onset scoliosis(EOS). Although the complication profile with MCGR use has been reviewed, these reviews do not take into account important implants modifications, termed iterations, that were made due to early on postoperative complications is not well reported or understood.AIM To assess the effect of MCGR implant iterations on post-operative complications in EOS.METHODS A systematic review was performed to identify studies investigating MCGR specifically for the treatment of EOS, refined to those reporting the implant iteration, specifically the incorporation of the keeper plate to the implant design.Articles with mixed implant iteration usage were excluded. Complications following surgery were recorded as well as potential risk factors and compared between implant cohorts.RESULTS Although 20 articles were identified for inclusion, 5 included mixed implant iteration leaving a total of 271 patients identified through 15 clinical studies thatmet inclusion criteria. The average follow-up was 25.4-mo. Pre-keeper plate implants were utilized in 3 studies with a total of 49 patients. Overall, 115(42.4%)post-operative complications were identified, with 87% defined as major. The addition of the keeper plate significantly decreased the rate of post-operative complications per study(35.7% vs 80.6%, P = 0.036), and the rate of distraction failure(8.1% vs 40.8%, P = 0.02). Unplanned reoperation occurred in 69(26.7%)patients but was not different between implant iteration cohorts(25.5% without keeper plate vs 27.1% with keeper plate, P = 0.92).CONCLUSION MCGR for EOS has a cumulative complication rate of 42.4% but this is significantly reduced to 35.7% when reviewing only keeper-plate enabled implants. However, 25% of published articles included mixed implant iterations.Future studies should discern between implants iterations when reporting on the usage of MCGR for EOS.