[Telemedicine in the emergency room-An extension with potential? : Results of a recent survey]. / Telemedizin im Schockraum ­ eine Ergänzung mit Potenzial : Ergebnisse einer aktuellen Umfrage.

Critically injured patients pose great challenges for medical personnel in emergency room treatment. How can such a high workload due to a lack of personnel be reduced? Telemedicine can offer solutions here. With the help of external medical expertise, diagnoses and treatment processes are already significantly accelerated and optimized in other specialist areas. This possibility should now also be introduced into the care of critical trauma surgery patients. In this article, current emergency room treatment is reflected, problems are shown and future-oriented solutions are suggested.

[Trends in the surgical treatment of fractures of the pelvic ring : A nationwide analysis of operations and procedures code (OPS) data between 2005 and 2017]. / Trends in der operativen Therapie von Frakturen des Beckenrings : Eine bundesweite Analyse von OPS-Daten zwischen 2005 und 2017.

AIM: The aim of this study was to analyze the epidemiological trends and incidences in inpatient pelvic surgery in the period from 2005 to 2007. METHOD: Approximately 194 million anonymized diagnosis-related groups (DRG) inpatient records were collected by the German Federal Statistical Office between 2005 and 2017. These data were screened for pelvic procedures, gender and age of the patients. Statistical testing was performed using the χ2-test and Mann-Whitney U-test (p < 0.05). RESULTS: Between 2005 and 2017 the number of closed reduction and internal fixation of the pelvic ring with screw fixation increased by +1116%. The use of screw fixation for closed reduction and internal fixation of the sacroiliac joint increased by +800%. The number of cases of open reduction and internal fixation of fractures of the pelvic ring and pelvic rim increased by +185% and reposition with external fixator increased by +188%. In 2005 more surgical procedures were undertaken in male inpatients, whereas more surgical procedures were undertaken in female inpatients in 2017. In general, a large increase in the number of pelvic procedures was observed in the group of patients >50 years old. CONCLUSION: There was an increase in the number of all analyzed pelvic procedures between 2005 and 2017. Especially the use of screw fixation increased. The introduction of new techniques (e.g. screw fixation of the sacroiliac joint) and progress and innovation in the field of three-dimensional navigation techniques, the demographic trend, greater mobility and higher demands on functionality of older patients might explain this increase in pelvic procedures.

Does Cement Augmentation of the Sacroiliac Screw Lead to Superior Biomechanical Results for Fixation of the Posterior Pelvic Ring? A Biomechanical Study.

Background and Objectives: The stability of the pelvic ring mainly depends on the integrity of its posterior part. Percutaneous sacroiliac (SI) screws are widely implanted as standard of care treatment. The main risk factors for their fixation failure are related to vertical shear or transforaminal sacral fractures. The aim of this study was to compare the biomechanical performance of fixations using one (Group 1) or two (Group 2) standard SI screws versus one SI screw with bone cement augmentation (Group 3). Materials and Methods: Unstable fractures of the pelvic ring (AO/OTA 61-C1.3, FFP IIc) were simulated in 21 artificial pelvises by means of vertical osteotomies in the ipsilateral anterior and posterior pelvic ring. A supra-acetabular external fixator was applied to address the anterior fracture. All specimens were tested under progressively increasing cyclic loading until failure, with monitoring by means of motion tracking. Fracture site displacement and cycles to failure were evaluated. Results: Fracture displacement after 500 cycles was lowest in Group 3 (0.76 cm [0.30] (median [interquartile range, IQR])) followed by Group 1 (1.42 cm, [0.21]) and Group 2 (1.42 cm [1.66]), with significant differences between Groups 1 and 3, p = 0.04. Fracture displacement after 1000 cycles was significantly lower in Group 3 (1.15 cm [0.37]) compared to both Group 1 (2.19 cm [2.39]) and Group 2 (2.23 cm [3.65]), p ≤ 0.04. Cycles to failure (Group 1: 3930 ± 890 (mean ± standard deviation), Group 2: 3676 ± 348, Group 3: 3764 ± 645) did not differ significantly between the groups, p = 0.79. Conclusions: In our biomechanical setup cement augmentation of one SI screw resulted in significantly less displacement compared to the use of one or two SI screws. However, the number of cycles to failure was not significantly different between the groups. Cement augmentation of one SI screw seems to be a useful treatment option for posterior pelvic ring fixation, especially in osteoporotic bone.

Complex biomechanical properties of non-augmented and augmented pedicle screws in human vertebrae with reduced bone density.

BACKGROUND: In osteoporotic bone, the quality of the bone-to-implant interface is decreased, which may lead to early implant failure. Screw anchorage can be improved by augmentation. This effect is mainly investigated with a pull-out test. To our knowledge, the effect of cement augmentation in an in vivo physiological setup focusing on screw movement has not been investigated to date. The aim of this work was to investigate and compare augmented and native screw behavior in a physiologically related setup. METHODS: Twelve fresh-frozen human lumbar vertebrae were divided into two groups. Each vertebra was bilaterally instrumented with either non-augmented or augmented pedicle screw systems and loaded in a recently developed test setup that provided cyclic conditions comparable to a physiological gait. The cyclic loading should test the primary implant stability, comparable to the postoperative period of two months in a worst-case scenario in the absence of osseous remodeling. Screws were tracked optically, and screw movement and failure patterns were observed. RESULTS: Mutual influence between the left and right sides resulted in a successive, rather than simultaneous, failure. Augmentation of the screws in vertebrae with poor bone quality reduced screw subsidence and thus improved the rigidity of the screw-to-implant interface by up to six-fold. The non-augmented condition was significantly related to early screw failure. CONCLUSIONS: Pedicle screw system failure involves a complex bilateral-coupled mechanism. The cyclic loading based on physiological conditions during walking has allowed the postoperative conditions and clinical failure mechanisms to be simulated in vitro and clarified. Future implant systems should be investigated with a physiologically related setup.

[Effects of the new injury type catalogue of the German statutory accident insurance on a center for severe injury type procedures]. / Auswirkungen des neuen Verletzungsartenverzeichnisses der DGUV auf ein SAV-Zentrum.

The development of the numbers of cases involved in accident insurance consultant procedures (DAV), injury type procedures (VAV) and severe injury type procedures (SAV) after the introduction of the new injury type catalogue from 1 July 2018 is presented. Furthermore, possible alterations to organizational aspects, such as operating room times and average duration of hospitalization are presented. A first critical assessment of the modifications in the new catalogue was carried out, particularly with reference to the newly introduced section on complications (section 11). METHODS: A retrospective study of all inpatients treated in the context of the DAV, VAV and SAV procedures at a SAV center from the 2nd and 3rd quarters of 2018 was carried out. The development of the number of cases, the case mix index (CMI), the mean number of operations, the mean time in the operating room and the length of hospitalization were analyzed. Furthermore, an assessment of the SAV cases was carried out with respect to the new developments and with particularly reference to complications. RESULTS: The total number of inpatients in the context of the DAV, VAV, SAV procedures changed only slightly. There was a clear decrease in DAV cases and a relevant increase in SAV cases. The CMI increased by 47%, the number of surgical procedures by 15%, the mean time in the operating room by 36% and the length of hospitalization by 43%. When converted to a daily operating room unit of 7 h (Tagestischeinheit, TTE) the operating room time increased from 89 to 108 TTE and the length of hospitalization increased from 1028 to 1358 days. Of the 111 SAV cases in the 3rd quarter, 52% were assigned to the catalogue number 11 "complications". In comparison to the previous version of the VAV/SAV catalogue, it was now possible to assign all inpatients to a single category. CONCLUSION: The modifications of the VAV in the observational period led to an enormous increase in SAV cases. It remains to be seen whether this development is confirmed in subsequent quarters. The increase in CMI, the number of necessary operations, operating room times and duration of hospitalization showed the necessity of these innovations on structural changes of hospitals involved in the treatment of SAV cases.

Management of destructive Candida albicans spondylodiscitis of the cervical spine: a systematic analysis of literature illustrated by an unusual case.

PURPOSE: Candida induced spondylodiscitis of the cervical spine in immunocompetent patients is an extremely rare infectious complication. Since clinical symptoms might be nonspecific, therapeutic latency can lead to permanent spinal cord damage, sepsis and fatal complications. Surgical debridement is strongly recommended but there is no standard antimycotic regime for postsurgical treatment. This paper summarizes available data and demonstrates another successfully treated case. METHODS: The systematic analysis was performed according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. PubMed and Web of Science were scanned to identify English language articles. Additionally, the authors describe the case of a 60-year-old male patient who presented with a Candida albicans induced cervical spondylodiscitis after an edematous pancreatitis and C. albicans sepsis. Anterior cervical corpectomy and fusion of C4-C6, additional anterior plating, as well as posterior stabilization C3-Th1 was followed by a 6-month antimycotic therapy. There was neither funding nor conflict of interests. RESULTS: A systematic literature analysis was conducted and 4599 articles on spondylodiscitis were scanned. Only four cases were found reporting about a C. albicans spondylodiscitis in a non-immunocompromised patient. So far, our patient was followed up for 2 years. Until now, he shows free of symptoms and infection parameters. Standard testing for immunodeficiency showed no positive results. CONCLUSION: Candida albicans spondylodiscitis of the cervical spine presents a potentially life-threatening disease. To our knowledge, this is the fifth case in literature that describes the treatment of C. albicans spondylodiscitis in an immunocompetent patient. Surgical debridement has to be considered, following antimycotic regime recommendations vary in pharmaceutical agents and treatment duration.

Treatment of proximal humerus fractures with a CFR-PEEK plate: 2-year results of a prospective study and comparison to fixation with a conventional locking plate.

BACKGROUND: A radiolucent carbon fiber-reinforced polyetheretherketone (CFR-PEEK) plate was recently introduced for fixation of proximal humerus fractures. Prospective clinical and radiographic results of patients treated with a CFR-PEEK plate are compared with those of patients treated with a conventional locking plate. METHODS: Twenty-nine patients (mean age, 66 years) were treated with a CFR-PEEK plate for a 3- or 4-part proximal humerus fracture. Patients were clinically and radiographically re-examined at 6 weeks, 6 months, 12 months, and 24 months with the Simple Shoulder Test, Constant-Murley score (CMS), and Oxford Shoulder Score (OSS) as well as with simple radiographs. In addition, results were compared with a matched group of patients treated with a conventional locking plate. RESULTS: At the final follow-up examination at 24 months, patients achieved a mean Simple Shoulder Test score of 58%, a mean CMS of 71.3 points (range, 44-97), and a mean OSS of 27.4 points (range, 8-45). Bone union was confirmed in all patients. Compared with patients treated with the conventional locking plate, patients treated with the CFR-PEEK plate achieved significantly better results with regard to the CMS and the OSS (P = .038 and .029, respectively). Furthermore, loss of reduction with subsequent varus deformity was less frequently observed in the CFR-PEEK plate group. CONCLUSION: Fixation of proximal humerus fractures with a CFR-PEEK plate provides satisfying clinical and radiographic results after 2 years of follow-up. The results are comparable to those achieved with conventional locking plates.

Biomechanical evaluation of the Facet Wedge: a refined technique for facet fixation.

PURPOSE: Purpose of this paper is to evaluate the primary stability of a new approach for facet fixation the so-called Facet Wedge (FW) in comparison with established posterior fixation techniques like pedicle screws (PS) and translaminar facet screws (TLS) with and without anterior cage interposition. METHODS: Twenty-four monosegmental fresh frozen non-osteoporotic human motion segments (L2-L3 and L4-L5) were tested in a two-arm biomechanical study using a robot-based spine tester. Facet Wedge was compared with pedicle screws and translaminar screws as a stand-alone device and in combination with an anterior fusion cage. RESULTS: Pedicle screws, FW and translaminar screws could stabilize an intact motion segment effectively. Facet Wedge was comparable to PS for lateral bending, extension and flexion and slightly superior for axial rotation. Facet Wedge showed a superior kinematic capacity compared to translaminar screws. CONCLUSIONS: Facet Wedge offers a novel posterior approach in achieving primary stability in lumbar spinal fixation. The results of the present study showed that the Facet Wedge has a comparable primary stability to pedicle screws and potential advantages over translaminar screws.

Long-Term Follow-Up after Iliosacral Screw Fixation of Unstable Pelvic Ring Fractures.

(1) Background: High-energy injuries of the pelvic ring are rare. The wide application of iliosacral screw fixation of the posterior pelvic ring is relatively new. The aim of the present study was to evaluate the long-term quality of life. (2) Methods: All patients treated with an iliosacral screw for a posterior pelvic ring stabilization after high-energy trauma at a level 1 trauma center between 2005 and 2015 were included. Pelvic ring injuries were classified according to the Tile classification adapted by AO/ASIF. The clinical evaluation included the patient-oriented questionnaires surveys of the Majeed Score, Iowa Pelvic Score (IPS), Work Ability Index (WAI), SF-36, EQ5D-5L. (3) Results: A total of 84 patients were included with a median follow-up of 130.1 months (IQR 95.0-162.0 months). The median ISS was 22.5 (IQR 16.0-29.0), mean Majeed Score 83.32 (SD ± 19.26), IPS 77.88 (SD ± 13.96), WAI 32.71 (SD ± 11.31), SF-36 PF 71.25 (SD ± 29.61) and EQ5D-5L 0.83 (SD ± 0.21). There was a notably difference between uni- and bilateral pelvic fractures (p = 0.033) as well as a correlation with the ISS (p = 0.043) with inferior functional outcome measured by IPS. (4) Conclusions: Long-term follow-up of iliosacral screw fixation of unstable pelvic ring fractures showed a good quality of life and functional outcome with equal EQ5D-5L results and inferior SF-36 physical functioning compared to the German population.

Evaluation of Prehospital Undertriage in Relation to Trauma Team Activation-Results from a Prospective Study in 12 Level one German Trauma Centers.

Background/Objective: This prospective, multicenter observational cohort study was carried out in 12 trauma centers in Germany and Switzerland. Its purpose was to evaluate the rate of undertriage, as well as potential consequences, and relate these with different Trauma Team Activation Protocols (TTA-Protocols), as this has not been done before in Germany. Methods: Each trauma center collected the data during a three-month period between December 2019 and February 2021. All 12 participating hospitals are certified as supra-regional trauma centers. Here, we report a subgroup analysis of undertriaged patients. Those included in the study were all consecutive adult patients (age ≥ 18 years) with acute trauma admitted to the emergency department of one of the participating hospitals by the prehospital emergency medical service (EMS) within 6 h after trauma. The data contained information on age, sex, trauma mechanism, pre- and in-hospital physiology, emergency interventions, emergency surgical interventions, intensive care unit (ICU) stay, and death within 48 h. Trauma team activation (TTA) was initiated by the emergency medical services. This should follow the national guidelines for severe trauma using established field triage criteria. We used various denominators, such as ISS, and criteria for the appropriateness of TTA to evaluate the undertriage in four groups. Results: This study included a total of 3754 patients. The average injury severity score was 5.1 points, and 7.0% of cases (n = 261) presented with an injury severity score (ISS) of 16+. TTA was initiated for a total of 974 (26%) patients. In group 1, we evaluated how successful the actual practice in the EMS was in identifying patients with ISS 16+. The undertriage rate was 15.3%, but mortality was lower in the undertriage cohort compared to those with a TTA (5% vs. 10%). In group 2, we evaluated the actual practice of EMS in terms of identifying patients meeting the appropriateness of TTA criteria; this showed a higher undertriage rate of 35.9%, but as seen in group 1, the mortality was lower (5.9% vs. 3.3%). In group 3, we showed that, if the EMS were to strictly follow guideline criteria, the rate of undertriage would be even higher (26.2%) regarding ISS 16+. Using the appropriateness of TTA criteria to define the gold standard for TTA (group 4), 764 cases (20.4%) fulfilled at least one condition for retrospective definition of TTA requirement. Conclusions: Regarding ISS 16+, the rate of undertriage in actual practice was 15.3%, but those patients did not have a higher mortality.

Biomechanical evaluation of combined short segment fixation and augmentation of incomplete osteoporotic burst fractures.

BACKGROUND: Treating traumatic fractures in osteoporosis is challenging. Multiple clinical treatment options are found in literature. Augmentation techniques are promising to reduce treatment-related morbidity. In recent years, there have been an increasing number of reports about extended indication for augmentation techniques. However, biomechanical evaluations of these techniques are limited. METHODS: Nine thoracolumbar osteoporotic spinal samples (4 FSU) were harvested from postmortem donors and immediately frozen. Biomechanical testing was performed by a robotic-based spine tester. Standardized incomplete burst fractures were created by a combination of osteotomy-like weakening and high velocity compression using a hydraulic material testing apparatus. Biomechanical measurements were performed on specimens in the following conditions: 1) intact, 2) fractured, 3) bisegmental instrumented, 4) bisegmental instrumented with vertebroplasty (hybrid augmentation, HA) and 5) stand-alone vertebroplasty (VP). The range of motion (RoM), neutral zone (NZ), elastic zone (EZ) and stiffness parameters were determined. Statistical evaluation was performed using Wilcoxon signed-rank test for paired samples (p = 0.05). RESULTS: Significant increases in RoM and in the NZ and EZ (p < 0.005) were observed after fracture production. The RoM was decreased significantly by applying the dorsal bisegmental instrumentation to the fractured specimens (p < 0.005). VP reduced fractured RoM in flexion but was still increased significantly (p < 0.05) above intact kinematic values. NZ stiffness (p < 0.05) and EZ stiffness (p < 0.01) was increased by VP but remained lower than prefracture values. The combination of short segment instrumentation and vertebroplasty (HA) showed no significant changes in RoM and stiffness in NZ in comparison to the instrumented group, except for significant increase of EZ stiffness in flexion (p < 0.05). CONCLUSIONS: Stand-alone vertebroplasty (VP) showed some degree of support of the anterior column but was accompanied by persistent traumatic instability. Therefore, we would advocate against using VP as a stand-alone procedure in traumatic fractures. HA did not increase primary stability of short segment instrumentation. Some additional support of anterior column and changes of kinematic values of the EZ may lead one to suppose that additive augmentation may reduce the load of dorsal implants and possibly reduce the risk of implant failure.

Mortality Risk Factors of Severely Injured Polytrauma Patients (Prehospital Mortality Prediction Score).

The aim of this study was to analyze the mortality of polytrauma patients and identify prediction parameters. A further aim was to create from the results a score for the prehospital predictive evaluation of 30-day survival. The study was conducted with a retrospective, observational design and was carried out unicentrically at a Level 1 Trauma Center. During the 4-year investigation period, patients with an Injury Severity Score (ISS) ≥ 16 were examined and their demographic basic data, laboratory values, and vital parameters were recorded. The mortality data analysis was performed using Kaplan-Meier Analysis and Log-Rank tests. Cox regressions were carried out to determine influencing factors and Receiver Operating Characteristic (ROC) curves were plotted to establish limit values for potential influencing factors. All statistical tests were conducted at a significance level of p ≤ 0.05. Coronary Heart Disease (CHD), cardiopulmonary resuscitation (CPR), age at admission, sex, and Glasgow Coma Scale (GCS) had a significant impact on the survival of polytrauma patients. The identified prediction parameters were combined with the shock index (SI). The generated score showed a sensitivity of 93.1% and a specificity of 73.3% in predicting the mortality risk. The study was able to identify significant influencing prehospital risk factors on 30-day survival after polytrauma. A score created from these parameters showed higher specificity and sensitivity than other prediction scores. Further studies with a larger number of participants and the inclusion of slightly injured patients could verify these findings.

[Position of trauma surgery in emergency medicine]. / Stellung der Unfallchirurgie in der Notfallmedizin.

BACKGROUND: The decision of the Federal Joint Committee has resulted in the further development of in-hospital emergency medicine through the establishment of central emergency departments and staged emergency care. In addition, the additional training in clinical acute and emergency medicine was established. AIM: The aim of this work is on the one hand to make trauma surgeons aware of these structural changes. On the other hand, we would like to evaluate an opinion and discuss the position of trauma surgery in emergency medicine. METHODS: A web-based online survey was conducted at the Trauma Network and Trauma Registry Congress to collect participants' opinions on the position of trauma surgery in emergency medicine. RESULTS: Of 143 congress participants, 98 (67%) responded to the survey. The majority of participants were male (n = 78, 80%), over 40 years of age (n = 62, 63%), and in a professional position with staff responsibility (n = 73, 75%). Emergency medicine (mean: 84.8; SD: 18.7) and intensive care medicine (mean: 78.3; SD: 20.4) training appears important. On the other hand, subsequent work in these areas appears less important (prehospital emergency medicine: mean: 65.1; SD: 28.0; ICU: mean: 53.7, SD: 30.3); however, activity in an emergency department is rated higher (MW: 87.0; SD: 18.7). There is high agreement that the trauma leader should be a trauma surgeon (mean 87.9; SD: 19.7). DISCUSSION: A high volume of emergency trauma surgery patients and the care of severely injured patients in designated trauma centers show that trauma surgery expertise is mandatory in a central emergency department. Senior positions should also be sought to ensure high quality standards.

Experimentally induced incomplete burst fractures - a novel technique for calf and human specimens.

BACKGROUND: Fracture morphology is crucial for the clinical decision-making process preceding spinal fracture treatment. The presented experimental approach was designed in order to ensure reproducibility of induced fracture morphology. RESULTS: The presented method resulted in fracture morphology, found in clinical classification systems like the Magerl classification. In the calf spine samples, 70% displayed incomplete burst fractures corresponding to type A3.1 and A3.2 fractures. In all human samples, superior incomplete burst fractures (Magerl A3.1) were identified by an independent radiologist and spine surgeon. CONCLUSIONS: The presented set up enables the first experimental means to reliably model and study distinct incomplete burst fracture patterns in an in vitro setting. Thus, we envisage this protocol to facilitate further studies on spine fracture treatment of incomplete burst fractures.

Cooperative effects in differentiation and proliferation between PDGF-BB and matrix derived synthetic peptides in human osteoblasts.

BACKGROUND: Enhancing osteogenic capabilities of bone matrix for the treatment of fractures and segmental defects using growth factors is an active area of research. Recently, synthetic peptides like AC- 100, TP508 or p-15 corresponding to biologically active sequences of matrix proteins have been proven to stimulate bone formation. The platelet-derived growth factor (PDGF) BB has been identified as an important paracrine factor in early bone healing. We hypothesized that the combined use of PDGF-BB with synthetic peptides could result in an increase in proliferation and calcification of osteoblast-like cells. METHODS: Osteoblast-like cell cultures were treated with PDGF and synthetic peptides, singly and as combinations, and compared to non-treated control cell cultures. The cultures were evaluated at days 2, 5, and 10 in terms of cell proliferation, calcification and gene expression of alkaline phosphate, collagen I and osteocalcin. RESULTS: Experimental findings revealed that the addition of PDGF, p-15 and TP508 and combinations of PDGF/AC-100, PDGF/p-15 and PDGF/TP508 resulted in an increase in proliferating osteoblasts, especially in the first 5 days of cultivation. Proliferation did not significantly differ between single factors and factor combinations (p > 0.05). The onset of calcification in osteoblasts occurred earlier and was more distinct compared to the corresponding control or PDGF stimulation alone. Significant difference was found for the combined use of PDGF/p-15 and PDGF/AC-100 (p < 0.05). CONCLUSIONS: Our findings indicate that PDGF exhibits cooperative effects with synthetic peptides in differentiation and proliferation. These cooperative effects cause a significant early calcification of osteoblast-like cells (p < 0.05). We suggest the combination of synthetic peptides and PDGF as a potential clinical approach for accelerating bone healing or coating osteosynthesis materials.

The S2-Alar-Iliac Screw for Pelvic Trauma. / Die S2-Ala-Ilium-Schraube in der Beckentraumatologie.

Percutaneous sacro-iliac screw osteosynthesis is considered to be standard of care for most posterior pelvic ring fractures. However, special situations require alternative strategies for sufficient stabilization. In these cases, stabilization can often be achieved using posterior instrumentation e.g. using SIPS-screws (spina-iliaca-posterior-superior screws). However, this often leads to implant-related aggravation of the sometimes already critical soft tissue conditions after pelvic trauma. S2-Ala-Ilium screws (S2AI screws) are a suitable alternative. The starting point lies medial of the posterior superior iliac spine below the iliac level. It is almost in line with a potential spinal instrumentation and therefore usually causes fewer soft tissue problems. Although this technique has been widely used in spinal surgery in recent years, its use in orthopaedic traumatology is largely unknown. The possibilities but also the limitations of this technique for the treatment of injuries to the pelvis are illustrated by this retrospective case series.

Biomechanical Comparison of Five Fixation Techniques for Unstable Fragility Fractures of the Pelvic Ring.

BACKGROUND: Incidence of pelvic ring fractures has increased over the past four decades, especially after low-impact trauma-classified as fragility fractures of the pelvis (FFP). To date, there is a lack of biomechanical evidence for the superiority of one existing fixation techniques over another. An FFP type IIc was simulated in 50 artificial pelvises, assigned to 5 study groups: Sacroiliac (SI) screw, SI screw plus supra-acetabular external fixator, SI screw plus plate, SI screw plus retrograde transpubic screw, or S1/S2 ala-ilium screws. The specimens were tested under progressively increasing cyclic loading. Axial stiffness and cycles to failure were analysed. Displacement at the fracture sites was evaluated, having been continuously captured via motion tracking. RESULTS: Fixation with SI screw plus plate and SI screw plus retrograde transpubic screw led to higher stability than the other tested techniques. The S1/S2 ala-ilium screws were more stable than the SI screw or the SI screw plus external fixator. CONCLUSIONS: In cases with displaced fractures, open reduction and plate fixation provides the highest stability, whereas in cases where minimally invasive techniques are applicable, a retrograde transpubic screw or S1/S2 ala-ilium screws can be considered as successful alternative treatment options.

Is Anterior Plating Superior to the Bilateral Use of Retrograde Transpubic Screws for Treatment of Straddle Pelvic Ring Fractures? A Biomechanical Investigation.

BACKGROUND: Fractures of the four anterior pubic rami are described as "straddle fractures". The aim of this study was to compare biomechanical anterior plating (group 1) versus the bilateral use of retrograde transpubic screws (group 2). METHODS: A straddle fracture was simulated in 16 artificial pelvises. All specimens were tested under progressively increasing cyclic loading, with monitoring by means of motion tracking. RESULTS: Axial stiffness did not differ significantly between the groups, p = 0.88. Fracture displacement after 1000-4000 cycles was not significantly different between the groups, p ≥ 0.38; however, after 5000 cycles it was significantly less in the retrograde transpubic screw group compared to the anterior plating group, p = 0.04. No significantly different flexural rotations were detected between the groups, p ≥ 0.32. Moreover, no significant differences were detected between the groups with respect to their cycles to failure and failure loads, p = 0.14. CONCLUSION: The results of this biomechanical study reveal less fracture displacement in the retrograde transpubic screw group after long-term testing with no further significant difference between anterior plating and bilateral use of retrograde transpubic screws. While the open approach using anterior plating allows for better visualization of the fracture site and open reduction, the use of bilateral retrograde transpubic screws, splinting the fracture, presents a minimally invasive and biomechanically stable technique.

Impact of the first COVID-19 shutdown on patient volumes and surgical procedures of a Level I trauma center.

PURPOSE: In Dec 2019, COVID-19 was first recognized and led to a worldwide pandemic. The German government implemented a shutdown in Mar 2020, affecting outpatient and hospital care. The aim of the present article was to evaluate the impact of the COVID-19 shutdown on patient volumes and surgical procedures of a Level I trauma center in Germany. METHODS: All emergency patients were recorded retrospectively during the shutdown and compared to a calendar-matched control period (CTRL). Total emergency patient contacts including trauma mechanisms, injury patterns and operation numbers were recorded including absolute numbers, incidence proportions and risk ratios. RESULTS: During the shutdown period, we observed a decrease of emergency patient cases (417) compared to CTRL (575), a decrease of elective cases (42 vs. 13) and of the total number of operations (397 vs. 325). Incidence proportions of emergency operations increased from 8.2 to 12.2% (shutdown) and elective surgical cases decreased (11.1 vs. 4.3%). As we observed a decrease for most trauma mechanisms and injury patterns, we found an increasing incidence proportion for severe open fractures. Household-related injuries were reported with an increasing incidence proportion from 26.8 to 47.5% (shutdown). We found an increasing tendency of trauma and injuries related to psychological disorders. CONCLUSION: This analysis shows a decrease of total patient numbers in an emergency department of a Level I trauma center and a decrease of the total number of operations during the shutdown period. Concurrently, we observed an increase of severe open fractures and emergency operations. Furthermore, trauma mechanism changed with less traffic, work and sports-related accidents.