Pelvic antropometric measurement in 3D CT for placement of two unilateral iliosacral S1 - 7.3 mm screws.

PURPOSE: Stability of the dorsal pelvic ring is important for patient mobilisation and can be restored using several surgical procedures after fracture. Placement of percutaneous iliosacral screws is a reliable and minimal-invasive technique to achieve stabilisation of the dorsal pelvic ring by placement of two screws in the first sacral vertebra. Aim of this study was to evaluate 3D CT scans regarding the anatomical possibility to place two 7.3 mm iliosacral screws for fixation of the dorsal pelvic ring. METHODS: 3D CT datasets of 500 consecutive trauma patients with 1000 hemipelves of a mid-european level I trauma centre with or without pelvic injury were evaluated and measured bilaterally in this retrospective study. RESULTS: One thousand hemipelvic datasets of 500 patients (157 females, 343 males) with a mean age of 49.7 years (18 to 95) were included in this study. Only 16 hemipelves (1.6%, 11 in females, 5 in males) in 14 patients (2.8%, 9 females = 5.73%, 5 males = 1.5%) showed too narrow corridors so that 7.3 mm screw placement would not be possible (p = 0.001). In women, too narrow corridors occurred 3.9 times as often as in men. Only two females showed this bilaterally. CONCLUSION: The evaluation of 3D CT scans of the pelvis showed the importance of planning iliosacral screw placement, especially if two 7.3 mm screws are intended to be placed in the first sacral vertebra.

No effect of tourniquet in primary total knee arthroplasty on muscle strength, functional outcome, patient satisfaction and health status: a randomized clinical trial.

PURPOSE: Tourniquet use during primary total knee arthroplasty (TKA) may negatively impact the early postoperative functional recovery due to molecular effects of ischaemia. The hypothesis of the present study was that primary TKA without a tourniquet positively influences the postoperative muscle strength, functional outcome, patient satisfaction and health status. METHODS: The monocentric, randomized, controlled trial included a total of 99 patients scheduled to undergo primary TKA (ClinicalTrials.gov NCT02475603). The patients were randomly assigned to the tourniquet (n = 50) or non-tourniquet (n = 49) group after receiving a written informed consent. As primary outcome parameter, the functional outcome, patient expectation/satisfaction and the health status were assessed preoperatively, 6 weeks, 6 months postoperatively using Oxford knee score, WOMAC score, Mancuso score, EQ-5D index, EQ-VAS, anxiety score, depression score, hospital anxiety and depression scale, respectively. Additionally, a rope pulley isokinetic system (Moflex, Recotec/Bernina, Switzerland) was applied to quantify the muscle strength preoperatively, 1 week, 6 weeks and 6 months postoperatively. RESULTS: No difference in any of the outcome parameters could be observed between the groups at all time points after TKA (n.s.). Also the isokinetic muscle strength of the knee joint as quantified by concentric/eccentric peak force (N), workload (J), total workload (J) and power (W) did not reveal statistically significant differences between the groups and time points. However, in both groups improved results were found with respect to the functional outcome, patient satisfaction, health status and isokinetic muscle strength up to 6 months postoperatively. CONCLUSIONS: The application of the tourniquet did not affect the isokinetic muscle strength, the functional outcome, the patient satisfaction and the health status following primary TKA. However, with and without tourniquet use, the level of the knee functionality, the patient satisfaction as well as the health status improved significantly. LEVEL OF EVIDENCE: I.

Combined kyphoplasty and intraoperative radiotherapy (Kypho-IORT) versus external beam radiotherapy (EBRT) for painful vertebral metastases - a randomized phase III study.

BACKGROUND: The spine is the most frequent location of bone metastases. Local treatment aims at palliation of pain and, given the increased likelihood of long-term cancer survival, at local control. Kyphoplasty and intraoperative radiotherapy (Kypho-IORT) provided instantaneous pain relief in 70% of patients at the first day after the intervention and resulted in local control rates of > 93% at 1 year in a recently conducted phase I/II trial. To assess its clinical value, we designed a phase III trial which tests Kypho-IORT against the most widespread standard-of-care, external beam radiotherapy (EBRT), in patients with painful vertebral metastases. METHODS: This phase III study includes patients ≥50 years of age with up to 4 vertebral metastases and a pain score of at least 3/10 points on the visual/numeric analogy scale (VAS). Patients randomized into the experimental arm (A) will undergo Kypho-IORT (Kyphoplasty plus IORT with 8 Gy prescribed to 13 mm depth). Patients randomized into the control arm (B) will receive EBRT with either 30 Gy in 10 fractions or 8 Gy as a single dose. The primary end point is pain reduction defined as at least - 3 points on the VAS compared to baseline at day 1. Assuming that 40% of patients in the Kypho-IORT arm and 5% of patients in the control arm will achieve this reduction and 20% will drop out, a total of 54 patients will have to be included to reach a power of 0.817 with a two-sided alpha of 0.05. Secondary endpoints are evaluation of the percentage of patients with a pain reduction of at least 3 points at 2 and 6 weeks, local tumor control, frequency of re-intervention, secondary fractures/sintering, complication rates, skin toxicity/wound healing, progression-free survival (PFS), overall survival (OS) and quality of life. DISCUSSION: This trial will generate level 1 evidence on the clinical value of a one-stop procedure which may provide instantaneous pain relief, long-term control and shortened intervals to further adjuvant (systemic) therapies in patients with spinal metastases. TRIAL REGISTRATION: Registered with ClinicalTrials.gov, number: NCT02773966 (Registration date: 05/16/2016).

Tourniquet application does not affect the periprosthetic bone cement penetration in total knee arthroplasty.

PURPOSE: Poor scientific evidence exists on the issue of tourniquet application during total knee arthroplasty (TKA). It has been suggested that tourniquet application might improve interdigitation of the cement into the periprosthetic bones due to relatively dry surgical field. The hypothesis of the present study was that tourniquet use did not affect the periprosthetic bone cement penetration. METHODS: The single-centre, randomized, controlled trial included 86 patients undergoing primary TKA (Clinical-Trials.gov NCT02475603). All patients meeting the inclusion criteria were randomly assigned to the tourniquet (n = 43) or non-tourniquet (n = 43) group after obtaining a written informed consent. The cumulative bone cement penetration was radiologically measured in AP (seven zones) and lateral views (three zones) as defined by Knee Society Scoring System. Further parameters such as perioperative blood loss, soft tissue swelling, pain level/analgesic consumption, operative time, length of hospital stay (LOS) and complication rate were statistically compared between the groups. RESULTS: The cumulative bone cement penetration averaged 28.5 ± 1.7 mm in tourniquet versus 26.6 ± 1.6 mm in non-tourniquet groups (n.s.). The mean intraoperative blood loss was 250 ml higher in the non-tourniquet group (p = 0.0001). Patient-reported pre- to 6th-day post-operative reduction of the pain level was significantly higher in the non-tourniquet group (p = 0.003). The Morphine Equivalent Dose was higher in the Tourniquet group at discharge day (p = 0.02). Parameters such as total blood loss, soft tissue swelling, surgical time, LOS, and complication rates revealed similar results between the groups. CONCLUSIONS: Tourniquet application did not influence the bone cement penetration significantly. Even though the intraoperative blood loss was reduced, the total blood loss was not affected significantly by tourniquet use. There was a tendency of higher post-operative pain and opioid analgesic requirement in the tourniquet group. LEVEL OF EVIDENCE: I.

[Measuring Satisfaction with Deployment in the Final Year of Undergraduate Medical Study (Ma-FEZ-PJ) to Ensure the Quality of Training in the Final Year - Psychometrics of a Self-Evaluation Questionnaire]. / Erfassung der Zufriedenheit mit dem Einsatz im Praktischen Jahr (Ma-FEZ-PJ) zur Qualitätssicherung der Lehre im Praktischen Jahr ­ Psychometrie eines Selbsteinschätzungsfragebogens.

INTRODUCTION: One way to recruit junior physicians in surgery is to optimise the final year. Starting points for this can be gained through a standardised evaluation of the deployments in the final year. In this study, a questionnaire for the evaluation of the training conditions and satisfaction with the deployment in the final year (Ma-FEZ-PJ) underwent a test and item analysis. In addition, initial studies were carried out to analyse the construct validity of the two scales - final year training and individual attitude. A specific example will then be used to show how the Ma-FEZ-PJ can be used to optimise the final year. METHODS: 555 medical students from eight final year cohorts evaluated their deployments in the final year with the Ma-FEZ-PJ. The reliability of the two scales as well as item characteristics were calculated. To validate construct validity, a global satisfaction item was used to verify the convergent validity of the final year training scale, which captures training conditions and satisfaction with the final year, and the divergent validity of the individual attitude scale. Groups of students who voluntarily or involuntarily attended the mandatory subjects in the final year were then compared to show whether the individual attitude scale can differentiate between the two. RESULTS: The reliability of the scale final year training is very good, that of the scale individual attitude is in the acceptable range. The construct validity can be sufficiently confirmed. DISCUSSION: The Ma-FEZ-PJ can be used as a tool to evaluate training conditions and satisfaction with the final year's deployment. Comparisons with other surgical departments, oriented at the scale level and then in detail at the item level, identify deficits in final year training and therefore approaches to optimise it.

[Mandatory Surgical Subinternship in the Final Year of Medical School - a Stepping Stone to Becoming a Surgeon?] / Chirurgisches Pflichttertial im Praktischen Jahr ­ das Sprungbrett in die chirurgische Weiterbildung?

BACKGROUND: The final year is an important time for a medical student as this is when medical knowledge is transformed into medical responsibilities. The field of surgery is firmly anchored in the educational structure as it is mandatory during the practical year of a medical student. The purpose of this paper is to identify factors that influence medical students to choose surgery after the final year of medical school. MATERIALS AND METHODS: An online survey conducted by the AG DGOU 2012 provided complete data sets from a total of 9079 participants. 184 of these had already completed their PJ compulsory sub-internship (tertiary) surgery. These were divided into four groups for analysis: decision to specialise in surgery prior to the PJ compulsory tertiary ("yes, before", JV), during the PJ compulsory ("yes, during", JW), decision against before the PJ compulsory ("no, before", NV) or during the compulsory ("no, during", NW). The total of 38 survey items were summarised for overall assessment, taking into account the decision on subject specialisation. RESULTS: 57.9% of the respondents were positive regarding the overall impression of the surgical internship during their final year. The respondents of the JW group were especially positive, having made the decision to become a surgeon, based on their internship experience during the final year in comparison to the NW group (decision against surgery). We find significant differences in all analysed items: integration into team JW/NW (p ≤ 0.003), acquisition of expertise (p ≤ 0.014), teachers (p ≤ 0.025), quality and structure of teaching (p ≤ 0.043) and overall satisfaction with the required tertial (p ≤ 0.037). CONCLUSION: In comparison to other specialities, in the field of surgery there is the option of recruiting directly within the framework of the compulsory internship. The results reveal unsatisfactory structures from a student perspective. The lack of medical care/support, the insufficient inclusion in therapeutic considerations, the lack of professional knowledge and lack of contact with the teachers are just a few key points that negatively impact the overall outcome of students' satisfaction with the compulsory tertiary education. The results of the present study should serve as motivation and contribute to the restructuring of the compulsory core of the Practical Year, which the Master Plan 2020 will entail.

[National Learning Objectives Catalogue in Surgery - General Part Defining Competences of Medical School Graduates in Surgery]. / Nationaler Kompetenzbasierter Lernzielkatalog Chirurgie ­ allgemeiner Teil mit fachbezogenen ärztlichen Handlungskompetenzen am Ende des Praktischen Jahres.

Competency-based medical education is needed in order to meet the requirements of medical care currently and in the future. The basis of this are activity-based learning objectives that are merged in competency-based catalogues. A basis for a core curriculum of undergraduate medical training is the National Catalogue of Learning Objectives for Undergraduate Medical Education (NKLM). Already in 2013, for surgery, the competencies which medical students should have achieved after completing the practical year (PJ) in relation to surgical diseases were defined in the special part of the National Catalogue of Learning Objectives in Surgery (NKLC). In the now amended general part of the NKLC, interdisciplinary competencies were defined and consented from all surgical disciplines, that are relevant for all surgical disciplines and that all representatives from the different surgical disciplines should incorporate in their surgical training. The complete NKLC is now available for faculties, teachers and students for trial (available online: https://www.dgch.de/index.php?id=190&L=528). The guiding principle for the entire development process was to make sure that students gain all competencies they need when starting to work as a medical doctor and therefor to increase patient safety.

[Position Paper of the Surgical Working Group for Teaching of the German Society of Surgery Regarding the "Master Plan 2020"]. / Positionspapier der chirurgischen Arbeitsgemeinschaft Lehre für die Deutsche Gesellschaft für Chirurgie zum "Masterplan Medizinstudium 2020".

The "Masterplan Medizinstudium 2020" from the German Federal Government should not be underestimated as only one among many announcement. Thus, the Surgical Working Group on Medical Education (CAL) of the German Association of Surgeons (DGCH) comments on the intended measures of the "Masterplan Medizinstudium 2020" and discusses the challenges, consequences and duties arising from the "Masterplan Medizinstudium 2020" for the representatives of the surgical societies and those engaged in surgical undergraduate training.

Tourniquet application during TKA did not affect the accuracy of implant positioning: a randomized clinical trial.

PURPOSE: The accuracy of the identification of anatomical landmarks with versus without tourniquet application and its effect on implant positioning remained unknown. Therefore, the hypothesis of the present study was that tourniquet application did not affect the accuracy of the reconstruction of the mechanical leg alignment, the joint line level, and the patellar height. METHODS: The prospective randomized monocentric trial (Clinical-Trials.gov NCT02475603) included a total of 86 patients scheduled to undergo primary TKA. The patients were allocated to receive TKA with (Group A, n = 43) or without tourniquet (Group B, n = 43). The mechanical leg alignment, the joint line level (modified Kawamura), and the patellar height (Plateau-patella angle, Insall Salvati index, and modified Insall Salvati index) were measured pre- and postoperatively on standardized calibrated digital radiographs. Mean, SEM, median, range, and p value were calculated for each parameter. RESULTS: There was no statistical difference between the groups with regard to demographics, preoperative deformity, implant design, and surgical technique (n.s.). The mechanical leg alignment, the joint line level, and the patellar height revealed, in both groups, similar results pre- and postoperatively (n.s.). CONCLUSION: The mechanical leg alignment, the joint line level, and the patellar height could be accurately reconstructed with and without tourniquet use. With respect to clinically relevant surrogate parameters of implant positioning, TKA can safely be performed without a tourniquet. Available data do not support a routine use of tourniquet during TKA and might justify a change of the clinical pathway. LEVEL OF EVIDENCE: Level I.

Twelve tips for successfully implementing logbooks in clinical training.

BACKGROUND: Logbooks are widely used to set learning outcomes and to structure and standardize teaching in clinical settings. Experience shows that logbooks are not always optimally employed in clinical training. In this article, we have summarized our own experiences as well as results of studies into twelve tips on how to successfully implement logbooks into clinical settings. METHODS: We conducted both a workshop concerning the importance of logbook training to exchange experiences in teaching practice, organization, didactic knowledge and a literature research to compare our own experiences and add additional aspects. RESULTS: Tips include the process of developing the logbook itself, the change-management process, conditions of training and the integration of logbooks into the curriculum. CONCLUSIONS: Logbooks can be a valuable tool for training in clinical settings, especially when multiple sites are involved, when you take our tips into consideration.

Tourniquet-induced ischaemia during total knee arthroplasty results in higher proteolytic activities within vastus medialis cells: a randomized clinical trial.

PURPOSE: Recent data suggest diminished post-operative quadriceps muscle strength after tourniquet application during total knee arthroplasty (TKA). The metabolic effects of the commonly utilized intraoperative tourniquet with consecutive ischaemia on the skeletal muscle cells were unknown. Ubiquitin proteasome system represents one of the main pathways involved in muscle protein breakdown contributing to muscle atrophy. Therefore, the purpose of the present study was to quantify the acute effects of the tourniquet application during TKA on the (1) concentrations of free/conjugated ubiquitin, (2) total ubiquitin-protein ligase activity, (3) proteasome-dependent and (4) proteasome-independent peptidase activities in the cells of vastus medialis. METHODS: The randomized, controlled, monocentric trial included 34 patients scheduled to undergo primary TKA. Each patient was randomly assigned to the tourniquet (n = 17) or non-tourniquet group (n = 17) after receiving a written consent. Muscle biopsies of (5 × 5 × 5 mm) 125 mm3 were obtained from vastus medialis immediately after performing the surgical approach and exactly 60 min later. After preparation of the muscle tissue specimen, the concentrations of the free/conjugated ubiquitin (Ub) were measured by western blot analyses. The ubiquitination was determined as biotinylated Ub incorporated into the sum of the cytosolic proteins and expressed as total ubiquitin-protein ligase activity (tUbPL). The quantification of the proteasome-dependent and proteasome-independent peptidase activities was performed with peptidase assays. RESULTS: Tourniquet application did not influence the concentration of the free/conjugated Ub. There were no differences in tUbPL activities between groups and time points. Tourniquet-induced ischaemia resulted in statistically significant higher proteasome-dependent (caspase-like p = 0.0034; chymotryptic-like p = 0.0013; tryptic-like p = 0.0036) and proteasome-independent (caspase-like p = 0.03; chymotryptic-like p = 0.0001; tryptic-like p = 0.0062) peptidase activities. CONCLUSION: Tourniquet application did not affect the free/conjugated Ub as well as tUbPL significantly, emphasizing the sophisticated regulation of ubiquitination. The proteasome-dependent peptidase activities were significantly upregulated during tourniquet application, suggesting an increase in protein degradation, which in turn might explain the skeletal muscle atrophy occurring after TKA. These findings add further knowledge and should raise the awareness of surgeons about the effects of tourniquet-induced ischaemia at the molecular level. Additional high-quality research may be warranted to examine the short- and long-term clinical significance of the present data. LEVEL OF EVIDENCE: I.

No trauma-related diagnosis in emergency trauma room whole-body computer tomography of patients with inconspicuous primary survey.

PURPOSE: Whole-body computer tomographic examinations (WBCT) are essential in diagnosing the severely injured. The structured clinical evaluation in the emergency trauma room, according to ATLS® and guidelines, helps to indicate the correct radiological imaging to avoid overtriage and undertriage. This retrospective, single-center study aimed to evaluate the value of WBCT in patients with an inconspicuous primary survey and whether there is any evidence for this investigation in this group of patients. METHODS: This retrospective, single-center study was conducted with patients admitted to a maximum-care hospital and supraregional trauma center in Germany and part of the TraumaNetwork DGU® in southwest Germany between January 2012 and November 2017. Hospital files were used for evaluation, and WBCT was carried out using a 32-row MSCT device from Siemens Healthineers, Volume Zoom, Erlangen, Germany. For evaluation, non-parametric procedures such as the chi-square test, U test, Fisher test, and Wilcoxon rank sum test were used to test for significance (p < 0.05). RESULTS: From 3976 patients treated with WBCT, 120 patients (3.02%) showed an inconspicuous primary survey. This examination did not reveal any trauma sequelae in any of this group. Additionally, 198 patients (4.98%) showed minor clinical symptoms in the primary survey, but no morphological trauma sequence could be diagnosed in WBCT diagnostics. Three hundred forty-two patients were not admitted as inpatients after WBCT and discharged to further outpatient treatment because there were no objectifiable reasons for inpatient treatment. Four hundred fifteen patients did not receive WBCT for, e.g., isolated extremity trauma, child, pregnancy, or death. CONCLUSION: Not one of the clinically asymptomatic patients had an imageable injury after WBCT diagnostics in this study. WBCT should only be performed in severely injured patients after clinical assessment regardless of "trauma mechanism." According to guidelines and ATLS®, the clinical examination seems to be a safe and reliable method for reasonable and responsible decision-making regarding the realization of WBCT with all well-known risk factors.

Titanium induces pro-inflammatory and tissue-destructive responses in primary human macrophages.

Implants and medical devices are efficient and practical therapeutic solutions for a multitude of pathologies. Titanium and titanium alloys are used in orthopedics, dentistry, and cardiology. Despite very good mechanical properties, and corrosion resistance titanium implants can fail due to inflammatory or tissue-degradation related complications. Macrophages are major immune cells that control acceptance of failure of the implant. In this study, for the first time, we have performed a systematic analysis of the response of differentially activated human macrophages (M(Control), M(IFNγ) and M(IL-4)) to the polished and porous titanium surfaces in order to identify the detrimental effect of titanium leading to the tissue destruction and chronic inflammation. Transcriptome analysis revealed that the highest number of differences between titanium and control settings are found in M(IL-4) that model healing type of macrophages. RT-qPCR analysis confirmed that both polished and porous titanium affected expression of cytokines, chitinases/chitinase-like proteins and matrix metalloproteinases. Titanium-induced release and activation of MMP7 by macrophages was enhanced by fibroblasts in both juxtacrine and paracrine cell interaction models. Production of titanium-induced MMPs and cytokines associated with chronic inflammation were independent of the presence of Staphylococcus aureus. MMP7, one of the most pronounced tissue-destroying factor and chitinase-like protein YKL-40 were expressed in CD68+ macrophages in peri-implant tissues of patients with orthopedic implants. In summary, we demonstrated that titanium induces pro-inflammatory and tissue-destructing responses mainly in healing macrophages, and the detrimental effects of titanium surfaces on implant-adjacent macrophages are independent on the bacterial contamination.

A Multi-Disciplinary MRI Assessment May Optimize the Evaluation of Chondral Lesions in Acute Ankle Fractures: A Prospective Study.

Chondral lesions (CL) in the ankle following acute fractures are frequently overlooked immediately after the injury or diagnosed at a later stage, leading to persistent symptoms despite successful surgery. The literature presents a wide range of discrepancies in the reported incidence of CLs in acute ankle fractures. The objective of this prospective study is to provide a precise assessment of the occurrence of chondral lesions (CLs) in acute ankle fractures through MRI scans conducted immediately after the trauma and prior to scheduled surgery. Furthermore, the study aims to highlight the disparities in the interpretation of these MRI scans, particularly concerning the size and extent of chondral damage, between radiologists and orthopedic surgeons. Over the period of three years, all patients presenting with an unstable ankle fracture that underwent operative treatment were consecutively included in this single-center prospective study. Preoperative MRIs were obtained for all included patients within 10 days of the trauma and were evaluated by a trauma surgeon and a radiologist specialized in musculoskeletal MRI blinded to each other's results. The location of the lesions was documented, as well as their size and ICRS classification. Correlations and kappa coefficients as well as the p-values were calculated. A total of 65 patients were included, with a mean age of 41 years. The evaluation of the orthopedic surgeon showed CLs in 52.3% of patients. CLs occurred mainly on the tibial articular surface (70.6%). Most talar lesions were located laterally (11.2%). The observed CLs were mainly ICRS grade 4. According to the radiologist, 69.2% of the patients presented with CLs. The most common location was the talar dome (48.9%), especially laterally. Most detected CLs were graded ICRS 3a. The correlation between the two observers was weak/fair regarding the detection and classification of CLs and moderate regarding the size of the detected CLs. To enhance the planning of surgical treatment for ankle chondral lesions (CLs), it may be beneficial to conduct an interdisciplinary preoperative assessment of the performed scans. This collaborative approach can optimize the evaluation of ankle CLs and improve overall treatment strategies.

Kyphoplasty and intra-operative radiotheray, combination of kyphoplasty and intra-operative radiation for spinal metastases: technical feasibility of a novel approach.

PURPOSE: To evaluate whether this new method is clinically applicable after theoretical and cadaver testing. METHODS: The incidence of spinal metastases requiring therapy is increasing, due to enhanced life expectancy. Due to results from studies with epidural compression a combined surgical and radiation therapy is often chosen. Minimal invasive cement augmentation is an increasingly used technique, due to fast pain relief and immediate stabilisation. On the other hand, stereotactic radiosurgery is considered to provide a more durable response and better local disease control than conventional radiotherapy with the application of higher doses. Therefore the combination of cement stabilisation and simultaneous intra-operative radiation with immediate stabilisation and high-dose radiation could be an interesting therapeutic option. The results of a clinical feasibility study are presented. RESULTS: 17 patients could be treated with the new method. In two patients (10%) intra-operative radiation could not be applied. No surgical interventions for complications were required. CONCLUSIONS: Summarizing Kypho-IORT is technically feasible with an intra-operative risk profile comparable to sole kyphoplasty and a shorter treatment time and hospitalisation for the patients compared to conventional multifraction radiation. Radiation could not be applied in 10% of cases due to technical difficulties. The results of this feasibility study permit further evaluation of this new technique by a dose escalation study which is currently in preparation.

Delayed diagnosed trauma in severely injured patients despite guidelines-oriented emergency room treatment: there is still a risk.

PURPOSE: Emergency trauma room treatment follows established algorithms such as ATLS®. Nevertheless, there are injuries that are not immediately recognized here. The aim of this study was to evaluate the residual risk for manifesting life-threatening injuries despite strict adherence to trauma room guidelines, which is different to missed injuries that describe recognizable injuries. METHODS: In a retrospective study, we included 2694 consecutive patients admitted to the emergency trauma room of one single level I trauma center between 2016 and 2019. In accordance with the trauma room algorithm, primary and secondary survey, trauma whole-body CT scan, eFAST, and tertiary survey were performed. Patients who needed emergency surgery during their hospital stay for additional injury found after guidelines-oriented emergency trauma room treatment were analyzed. RESULTS: In seven patients (0.26%; mean age 50.4 years, range 18-90; mean ISS 39.7, range 34-50), a life-threatening injury occurred in the further course: one epidural bleeding (13 h after tertiary survey) and six abdominal hollow organ injuries (range 5.5 h-4 days after tertiary survey). Two patients (0.07% overall) with abdominal injury died. The "number needed to fail" was 385 (95%-CI 0.0010-0.0053). CONCLUSION: Our study reveals a remaining risk for delayed diagnosis of potentially lethal injuries despite accurate emergency trauma room algorithms. In other words, there were missed injuries that could have been identified using this algorithm but were missed due to other reasons. Continuous clinical and instrument-based examinations should, therefore, not be neglected after completion of the tertiary survey. LEVEL OF EVIDENCE: Level II: Development of diagnostic criteria on the basis of consecutive patients (with universally applied reference "gold" standard).

Gene expression analysis of vastus medialis cells after tourniquet-induced ischemia during total knee arthroplasty: a randomized clinical trial.

PURPOSE: Postoperative quadriceps muscle strength was lowered after tourniquet application during total knee arthroplasty (TKA). Furthermore, tourniquet application results in higher proteolytic activity within vastus medialis cells, without influence on the amount and function of mitochondria. The effects of the commonly utilized intraoperative tourniquet on gene expression within the human skeletal muscle cells are barely examined. The purpose of the present study was to analyze the gene expression within the skeletal muscle cells after tourniquet-induced ischemia to identify differential expressed genes (DEGs) and pathways. METHODS: As part of a randomized, controlled, monocentric trial (Clinical-Trials.gov NCT02475603) 20 patients, scheduled to undergo primary total knee arthroplasty (TKA), were included. Written informed consent was received and the patients were randomly assigned to Group A (TKA with tourniquet) (n = 10) and Group B (TKA without tourniquet) (n = 10). A muscle biopsie of (5 × 5 × 5 mm) 125 mm3 were obtained from the vastus medialis exactly 60 min after performing the surgical approach. After preparation of a muscle homogenate, RNA extraction was performed (RNeasy Plus Universal Mini Kit Qiagen) and RNA integrity (RIN) was determined (Agilent 2100 Bioanalyzer, RNA 6000 Pico Kit). Gene expression profiling was performed using a validated method (GeneChip™ Human Transcriptome Array 2.0; Affymetrix). Statistical analysis (SPSS-Version 24; SAS JMP10 Genomics, Version 6) included the number of significant DEGs (p < 0.05), the number of DEGs with relative difference > 25% and the number of significant pathway (p < 0.05). The serum C-reactive protein (CRP) and the white blood cell (WBC) count were also perioperatively measured. The protocol was approved by our Institutional Ethics Committee (File reference 2012-334N-MA). RESULTS: Tourniquet application resulted in a total of 3555 (13.8%) statistically significant DEGs within vastus medialis cells. 76 DEGs (29 upregulated, 47 downregulated) revealed a relative difference of more than 25%. Statistically significant changes occurred in 59 (25.8%) of 229 analyzed pathways. Furthermore, there was no clinically meaningful difference between the groups with regard to CRP and WBC count. CONCLUSIONS: Tourniquet induced ischemia results in significant changes of the gene expression within cells of vastus medialis including metabolism, genetic information processing and cellular processes. The identified altered expression of genes and pathways might serve as pharmacotherapeutical targets; although further research is needed to clarify the underlying biological processes. CLINICAL RELEVANCE: These findings add further knowledge and should raise the awareness of surgeons about the effects of tourniquet induced ischemia at the gene expression level. Additional high-quality research may be warranted to examine the short and long term clinical significance of the present data. LEVEL OF EVIDENCE: Level I.

Checklist Focused on Patients for Making of Teaching Videos in Orthopedic Surgery. / Patientenorientierte Checkliste für die Erstellung von Lehrvideos für Orthopädie und Unfallchirurgie.

INTRODUCTION: The focus of medical-didactic research is the improvement of clinical-practical training. One way to support practical skills training in a time- and resource-saving way is to provide instructional videos. Often the freely available instructional videos do not meet didactic or content requirements. Creating your own videos can therefore be a useful alternative for teachers. There are a variety of instructions on the Internet for shooting instruction videos. To date, this does not include any concrete instructions/assistance for the production of medical instructional videos. However, the presentation of medical learning content in particular can contain many hurdles. The aim of this work was to design a checklist for the creation of instructional videos, which can be used as a guide. METHODS: As a first step, a systematic literature search was carried out to identify works that deal with the creation and not the use of medical instructional videos. To date, corresponding publications do not exist. In a workshop, the participants, who already gained experience in creating this type of video, exchanged ideas. These were critically discussed and analyzed. As a result, a checklist was created. In a subsequent multi-step review process, the checklist was reviewed with regard to applicability, comprehensibility, completeness and quality of the items. RESULTS: Four phases in the creation of an instructional video could be differentiated: preliminary reflections, preparation, day of filming, post-production. The checklist is structured accordingly and should be actively processed phase by phase. The checklist is created in such a way that it can be used and edited without reading this text. Particular focus is placed on the patient and his needs. CONCLUSION: The checklist created provides useful help in the creation of medical instructional videos and can for the first time serve as a guide especially for orthopedic and accident surgical instructional videos.

Evidence-Based Examination Techniques for the Shoulder Joint. / Evidenzbasiertes Lehrvideo für Untersuchungstechniken am Schultergelenk.

OBJECTIVE: Digitalisation now almost covers all areas of medical student teaching. Teaching videos are a good way to help students learn practical skills. The existing evidence is a recognised aid for the classification of the respective technology. METHOD: This video presents the usual examination techniques of the shoulder joint on a patient with an unstable shoulder. The respective techniques, if available, were backed up with appropriate evidence. CONCLUSION: The examination techniques presented allow students to view them in a standardized manner on a patient. The evidence for the examination techniques can help with the classification of the respective technique.

Evidence-Based Examination Techniques for the Knee. / Evidenzbasiertes Lehrvideo für Untersuchungstechniken am Kniegelenk.

OBJECTIVE: Digitalisation now almost covers all areas of medical student teaching. Teaching videos are a good way to help students learn practical skills. The existing evidence is a recognised aid for the classification of the respective technology. METHOD: This video presents the usual examination techniques of the knee joint on a patient with an unstable knee. The respective techniques, if available, were backed up with the appropriate evidence. CONCLUSION: The examination techniques presented allow students to view the examination techniques in a standardised manner on a patient. The evidence for the examination techniques can help with the classification of the respective technique. ZIELSETZUNG: Die Digitalisierung erfasst inzwischen alle Bereiche der studentischen Lehre. Um die Studierenden im Erlernen praktischer Fertigkeiten zu unterstützen, sind Lehrvideos eine gute Methode. Für die Einordnung der jeweiligen Technik ist die vorhandene Evidenz eine anerkannte Hilfestellung. METHODE: Das hier vorliegende Video stellt die üblichen Untersuchungstechniken des Kniegelenkes an einer Patientin mit einem instabilen Knie dar. Die jeweiligen Techniken wurden, wenn vorhanden, mit der jeweiligen Evidenz unterlegt. SCHLUSSFOLGERUNG: Die dargestellten Untersuchungstechniken ermöglichen es Studierenden, sich die Untersuchungstechniken standardisiert an einem Patienten anzuschauen. Die eingeblendete Evidenz für die Untersuchungstechniken kann hierbei eine Hilfestellung bei der Einordnung der jeweiligen Technik leisten.