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 the interhospital patient transfer after implementation of a regionalized trauma care system (TraumaNetzwerk DGU®) in Germany

Purpose

The aim of the study was to evaluate how many patients are being transferred between trauma centers and and their characteristics in the 2006 initiated TraumaNetzwerk DGU® (TNW). We further investigated the time point of transfer and differences in outcome, compared to patients not being transferred. We wanted to know how trauma centers judged the performance of the TNW in transfer.

Method

(1) We analyzed the data of the TraumaRegister DGU® (TR-DGU) from 2014-2018. Included were patients that were treated in German trauma centers, maximum AIS (MAIS) >2 and MAIS 2 only in case of admission on ICU or death of the patient. Patients being transferred were compared to patients who were not. Characteristics were compared, and a logistic regression analysis performed to identify predictive factors. (2) We performed a survey in the TNW focussing on frequency, timing and communication between hospitals and improvement through TNW.

Results

Study I analyzed 143,195 patients from the TR-DGU. Their mean ISS was 17.8 points (SD 11.5). 56.4% were admitted primarily to a Level-I, 32.2% to a Level-II and 11.4% to a Level-III Trauma Center. 10,450 patients (7.9%) were transferred. 3,667 patients (22.7%) of the admitted patients of Level-III Center and 5,610 (12.6%) of Level-II Center were transferred, these patients showed a higher ISS (Level-III: 18.1 vs. 12.9; Level-II: 20.1 vs. 15.8) with more often a severe brain injury (AIS 3+) (Level-III: 43.6% vs. 13.1%; Level-II: 53.2% vs. 23.8%). Regression analysis showed ISS 25+ and severe brain injury AIS 3+ are predictive factors for patients needing a rapid transfer. Study II: 215 complete questionnaires (34%) of the 632 trauma centers. Transfers were executed within 2 h after the accident (Level-III: 55.3%; Level-II: 25.0%) and between 2-6 h (Level-III: 39.5%; Level-II: 51.3%). Most trauma centers judged that implementation of TNW improved trauma care significantly (Level III: 65.0%; Level-II: 61.4%, Level-I: 56.7%).

Conclusion

The implementation of TNW has improved the communication and quality of comprehensive trauma care of severely injured patients within Germany. Transfer is mostly organized efficient. Predictors such as higher level of head injury reveal that preclinical algorithm present a potential of further improvement.

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]

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.

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.

[Telemedicine in the emergency room-An extension with potential? : Results of a recent survey]

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.

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 technique 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.

[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]

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.

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.

Differentiation of Traumatic Osteoporotic and Non-Osteoporotic Vertebral AO A3 Fractures by Analyzing the Posterior Edge Morphology-A Retrospective Feasibility Study

BACKGROUND

Differentiation between traumatic osteoporotic and non-osteoporotic vertebral fractures is crucial for optimal therapy planning. We postulated that the morphology of the posterior edge of the cranial fragment of A3 vertebral fractures is different in these entities. Therefore, the purpose of this study is to develop and validate a simple method to differentiate between osteoporotic and non-osteoporotic A3 vertebral fractures by morphological analysis.

METHODS

A total of 86 computer tomography scans of AO Type A3 (cranial burst) vertebral body fractures (52 non-osteoporotic, 34 osteoporotic) were included in this retrospective study. Posterior edge morphology was analyzed using the sagittal paramedian slice with the most prominent shaped bulging. Later, the degree of bulging of the posterior edge fragment was quantified using a geometric approach. Additionally, the Hounsfield units of the broken vertebral body, the vertebra above, and the vertebra below the fracture were measured.

RESULTS

We found significant differences in the extent of bulging comparing osteoporotic and non-osteoporotic fractures in our cohort. Using the presented method, sensitivity was 100%, specificity was 96%. The positive predictive value (PPV) was 94%. In contrast, by evaluating the Hounsfield units, sensitivity was 94%, specificity 94% and the PPV was 91%.

CONCLUSIONS

Our method of analysis of the bulging of the dorsal edge fragment in traumatic cranial burst fractures cases allows, in our cases, a simple and valid differentiation between osteoporotic and non-osteoporotic fractures. Further validation in a larger sample, including dual-energy X-ray absorptiometry (DXA) measurements, is necessary.

Safety, Effect and Feasibility of Percutaneous SI-Screw with and without Augmentation-A 15-Year Retrospective Analysis on over 640 Screws

BACKGROUND

Minimally invasive sacroiliac-screw (SI-screw) fixation of the pelvis is used in energy trauma (Arbeitsgemeinschaft für Osteosynthesefragen (AO) classified) and fragility fractures (Fragility Fracture of the Pelvis (FFP) classified). However, available clinical data are based on small case series and biomechanical data seem to be contradictory.

METHODS

The present single center retrospective cohort study investigated percutaneous SI-screw fixation and augmentation over 15 years. Groups were compared concerning the general epidemiological data, mobilization, complication rates, duration of stay, and safety of SI-screw insertion. Multivariable analyses were performed using logistic regression.

RESULTS

Between 2005 and March 2020, 448 patients with 642 inserted SI-screws were identified. Iatrogenic neurological impairment was documented in 2.47% and correlated with screw misplacement. There was an increased complication risk in patients with AO type C over patients with AO type B and in FFP II over FFP III/IV patients. Cement-augmented FFP patients showed a 25% reduced stay in hospital and a reduced complication risk. Cement-associated complications were seen in 22% without correlation to neurologic impairment.

CONCLUSIONS

The present study confirms the safety and usability of percutaneous SI-screw fixation, despite specific risks. Cement augmentation seems to reduce the complication risk in FFP patients and shorten hospital stay for some reasons, without increased specific complications or correlated neurological impairment.

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.

Recommendations for the Diagnostic Testing and Therapy of Atlas Fractures

Im Jahr 2017 erstellten die Mitglieder der AG „obere HWS“ der Sektion „Wirbelsäule“ der DGOU in einem Konsensusprozess mit 4 Sitzungen Empfehlungen zur Diagnostik und Therapie oberer Halswirbelsäulenverletzungen unter Berücksichtigung der aktuellen Literatur. Der folgende Artikel beschreibt die Empfehlung für Frakturen des Atlasrings. Etwa 10% aller HWS-Verletzungen betreffen den Atlas. Die Diagnostik zielt im Wesentlichen auf die Detektion der Verletzung sowie die Beurteilung der Gelenkflächen hinsichtlich einer Lateralisationstendenz der Atlasmassive. Zur Klassifikation haben sich die Gehweiler-Klassifikation und ergänzend die Dickman-Klassifikation bewährt. Zum primären klinischen Screening hat sich die Canadian C-Spine Rule bewährt. Bildgebendes Verfahren der Wahl bei klinischem Verdacht auf eine Atlasverletzung ist die CT. Die MRT dient der Beurteilung der Integrität des Lig. transversum atlantis bei vorderer und hinterer Bogenfraktur. Die Indikation zur Gefäßdarstellung sollte großzügig gestellt werden. Viele Atlasfrakturen können konservativ in einer Zervikalorthese behandelt werden. Eine OP-Indikation ist gegeben bei bestehender oder drohender massiver Gelenkinkongruenz oder -instabilität, die am häufigsten bei Gehweiler-IIIB-Frakturen oder bei Gehweiler-IV-Frakturen vorliegt. Operative Standardtherapie ist die dorsale atlantoaxiale Fixation, entweder in transartikulärer Technik oder mittels Fixateur interne. Insbesondere bei jüngeren Patienten sollte die Möglichkeit einer isolierten Atlasosteosynthese geprüft werden. Dislozierte Gehweiler-IV-Frakturen mit sagittaler Spaltbildung können auch probatorisch im Halofixateur unter Ausnutzung der Ligamentotaxis behandelt werden; eine engmaschige Dislokationskontrolle ist obligat. Im Falle einer sekundären Dislokation ist auch hier eine operative Stabilisierung indiziert. Bei Mitbeteiligung des okzipitozervikalen Gelenks ist eine Einbeziehung des Okziputs in die Instrumentierung notwendig.

Recommendations for Diagnosis and Treatment of Fractures of the Ring of Axis

In a consensus process with four sessions in 2017, the working group “upper cervical spine” of the German Society for Orthopaedics and Trauma Surgery (DGOU) formulated “Therapeutic Recommendations for the Diagnosis and Treatment of Upper Cervical Fractures”, taking their own experience and the current literature into consideration. The following article describes the recommendations for axis ring fractures (traumatic spondylolysis C2). About 19 to 49% of all cervical spine injuries include the axis vertebra. Traumatic spondylolysis of C2 may include potential discoligamentous instability C2/3. The primary aim of the diagnostic process is to detect the injury and to determine potential disco-ligamentous instability C2/3. For classification purposes, the Josten classification or the modified Effendi classification may be used. The Canadian C-spine rule is recommended for clinical screening for C-spine injuries. CT is the preferred imaging modality and an MRI is needed to determine the integrity of the discoligamentous complex C2/3. Conservative treatment is appropriate in case of stable fractures with intact C2/3 motion segment (Josten type 2 and 2). Patients should be closely monitored, in order to detect secondary dislocation as early as possible. Surgical treatment is recommended in cases of primary severe fracture dislocation or discoligamentous instability C2/3 (Josten 3 and 4) and/or secondary fracture dislocation. Anterior cervical decompression and fusion (ACDF) C2/3 is the treatment of choice. However, in case of facet joint luxation C2/3 with looked facet (Josten 4), a primary posterior approach may be necessary.

Imaging of Spontaneous and Traumatic Cervical Artery Dissection : Comparison of Typical CT Angiographic Features

INTRODUCTION

Cervical artery dissection (CAD) is an important etiology of ischemic stroke and early recognition is vital to protect patients from the major complication of cerebral embolization by administration of anticoagulants. The etiology of arterial dissections differ and can be either spontaneous or traumatic. Even though the historical gold standard is still catheter angiography, recent studies suggest a good performance of computed tomography angiography (CTA) for detection of CAD. We conducted this research to evaluate the variety and frequency of possible imaging signs of spontaneous and traumatic CAD and to guide neuroradiologists' decision making.

METHODS

Retrospective review of the database of our multiple injured patients admitted to the Department of Trauma, Hand, and Reconstructive Surgery of the University Hospital Münster in Germany (a level 1 trauma center) for patients with traumatic CAD (tCAD) and of our stroke database (2008-2015) for patients with spontaneous CAD (sCAD) and CT/CTA on initial clinical work-up. All images were evaluated concerning specific and sensitive radiological features for dissection by two experienced neuroradiologists. Imaging features were compared between the two etiologies.

RESULTS

This study included 145 patients (99 male, 46 female; 45 ± 18.8 years of age), consisting of 126 dissected arteries with a traumatic and 43 with spontaneous etiology. Intimal flaps were more frequently observed after traumatic etiology (58.1% tCADs, 6.9% sCADs; p < 0.001); additionally, multivessel dissections were much more frequent in trauma patients (3 sCADs, 21 tCADs) and only less than half (42%) of the patients with traumatic dissections showed cervical spine fractures.

CONCLUSION

Neuroradiologists should be aware that intimal flaps and multivessel dissections are more common after a traumatic etiology. In addition, it seems important to conduct a CTA in a trauma setting, even if no cervical spine fracture is detected.

Biomechanical characteristics of pedicle screws in osteoporotic vertebrae-comparing a new cadaver corpectomy model and pure pull-out testing

Currently, evaluation of the stability of spinal instrumentations often focuses on simple pull-out or cyclic loading. However, the loading characteristics and the specimen alignment rarely simulate physiological loading conditions, or the clinical situation itself. The purpose of this study was to develop an alternative setup and parameters to compare static and dynamic characteristics of pedicle screws at the bone-implant interface in lumbar osteoporotic cadavers. A corpectomy model development was based on ASTM-1717 standard, allowing a deflection of the cranial and caudal element under loading. Twelve human osteoporotic vertebrae (L1-L4) were analyzed for morphological CT-data and T-Score. For group A (n = 6) loads were simulated as in vivo measurements during walking, representing 2 months postoperatively. A subsequent pull-out was performed. Group B (n = 6) was tested with pure pull-out. Screw loosening at the tip/head was optically measured and analyzed with respect to clinical patterns. Correlations between CT-data, T-Score, and in vitro parameters were determined. For group A, the subsidence for the head/tip was measured towards the upper/lower endplate, resulting in visible deflections. The progress of the subsidence was greatest within the first and last cycles until failure. The predominant patterns were pure rotation and toggling. However, the pull-out between groups was not significantly different. Pedicle-angle and cyclic-subsidence correlated with R = 0.806/0.794. T-Score and pull-out correlated only in group A. With the corpectomy setup, clinically observed wipe effects and a loss of correction could be simulated. The presented parameters facilitate analysis of the complex changing load distributions and interactions between the left and right bone-implant interface. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:167-174, 2017.

[Comparison of ICD 10 and AIS with the Development of a Method for Automated Conversion]

BACKGROUND

Most of the current scores and outcome prediction calculations in traumatology are based on the Abbreviated Injury Scale (AIS). However, this is not routinely used for documentation and coding of injuries in many countries, including Germany. Instead of the AIS, the International Classification of Diseases (ICD) is used. While the ICD functions as the basis for automated calculating of the diagnosis-related groups (DRG), no possibility of simple conversion of the 10th version of the ICD into AIS is available so far.

OBJECTIVES

The aim of this work is to develop and apply a methodology for simple conversion from ICD 10 to current AIS.

MATERIALS AND METHODS

The developed mapping procedure was based on a 1 : n relationship between trauma codes of ICD-10-GM and the codes of the AIS2005. Calculated ISS from the conversion codes were then compared with the actual ISS coding available from the clinical trauma documentation.

RESULTS

It can be shown that, despite the considerable differences in the structure and systematic of both classification systems, an automated translation is technically possible.

CONCLUSIONS

The preliminary result of the mapping suggests, however, that despite the technical feasibility of a reliable conversion and comparability of ICD 10 and AIS in the required quality is still questionable. An automated conversion is still possible and quality would possibly improve by inclusion of additional information.

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.

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.

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.

Blunt cerebrovascular injuries in acute trauma care: a screening protocol

INTRODUCTION

Blunt cerebrovascular injuries (BCVI) of the extra- or intracerebral vessels are frequently observed lesions which may lead to thrombembolic events with focal neurological deficits, stroke or death particularly in patients <60 years. However, a comprehensive standardised clinical algorithm for screening and management of these secondary injuries is still lacking.

MATERIALS AND METHODS

We developed a standardised screening protocol applicable for mild as well as severely injured patients. In this prospective cohort study, we evaluated the feasibility of this diagnostic algorithm in a level 1 trauma centre setting. Trauma patients who met the inclusion criteria underwent a computed tomographic angiography (CTA) as part of standard diagnostic procedure at admission. All suspicions or positive findings were reevaluated by a conventional four-vessel catheter angiography within the first 72 h after trauma. Within this period, anticoagulation with low-dose heparin was started. BCVI confirmation indicated a shift to systemic heparinisation with overlapping phenprocoumon therapy for at least 6 months. All patients were reevaluated after 6 months by another four-vessel angiography. Depending on the diagnostic findings, oral anticoagulation may be discontinued or continued for another 6 months.

RESULTS

A total of 44 patients (8 male, 6 female, age range 19-95 years) were included in the study. 20 BCVIs were detected in 16 patients (36.3%). The most common injuries identified were Biffl Type II (40%) and Type IV lesions (30%). 86.4% of the patients received a CTA upon admission, 93.2% of which were conducted within 12 h posttrauma. None of the patients had a secondary thrombembolic neurological event during the hospital stay or within 3 months postdischarge.

CONCLUSION

Our results indicate that implementation of the screening protocol can prevent strokes in patients without primary thrombembolic neurological deficits.

Is there a way to diagnose spinal instability in acute burst fractures by performing ultrasound?

The aim of this study is to examine the predictive value of ultrasound diagnostics for the assessment of traumatic lesions of the posterior ligament complex (PLC) in burst fractures of the thoracolumbar spine. This was a prospective validating cohort study. Judgment about instability and treatment of burst fractures depends on the condition of the PLC. There have been some studies describing underdiagnosis of PLC injuries due to classification problems in ligamentary distraction type fractures. The gold standard for assessing these lesions is magnetic resonance imaging (MRI). Even then, there are often limits in contemporary operational availability and technical limitations of MRI. Ultrasound was described being an alternative. In a prospective study, 54 levels of 18 patients with acute burst fractures of the thoracic and lumbar spine have been examined by ultrasound and additional MRI scans preoperatively. The condition (intact vs. ruptured) of supraspinous ligament (SSL) and the interspinous ligament has been assessed for the ligaments separately. Hematoma below the SSL has also been evaluated as an indirect sign of an injured PLC. In all the patients the primary performed operative treatment was a posterior spinal instrumentation. Postoperatively the blinded results of the ultrasound procedures have been matched against intraoperative and MRI findings. Assessments of all target structures have been contributed to the calculation of the sensitivity and specificity of ultrasound. A total of 18 patients, 14 males and 4 females, with acute burst fractures have been qualified for inclusion in the study. The patients' mean age was 43.4 years. Comparing intraoperative findings with preoperatively performed investigations, ultrasound archived a sensitivity of 0.99 and a specificity of 0.75 (P < 0.05) to detect traumatic lesions to the PLC. As hypothesized the obtained predictive value using ultrasound correlates closely with intraoperative findings. Anyway MRI still seems to be the superior diagnostic method for examining the PLC. However, ultrasound can be considered to be an adequate alternative method in cases with contraindications for MRI such as ferromagnetic side effects, claustrophobia, availability or emergency diagnostics in multiple injuries.

Telematics in acute trauma care

Each year, 20,000 people in Germany die because of a traffic accident. Altogether, yearly productivity loss caused by these injuries is estimated to be around 5 billion Euros. International and national studies revealed the trauma center level of the primary hospital as the major predictor for trauma related mortality. In 2006 the German Society for Trauma Surgery (DGU) called its members to form regionally based networks for the exchange of data among hospitals engaged in trauma care. In April 2008 the north-west region of Germany with 49 hospitals, three hospitals in the Netherlands, and local emergency services founded the "TraumaNetwork NorthWest (TNNW). The major goals of the TNNW are: 1) to shorten the time between accident and admission to the appropriate hospital, 2) to create effective means of communication, and 3) to implement common pre- and in-hospital standards for trauma care. Since the needed application software is not commercially available, a team of computer and medical specialists has been formed for its development. Once the software is in place, a pre- and post-analysis will be performed to study the consequences of the application on transportation time and injury-related mortality within the region. The project is recognized as a pilot project by the DGU and if it is successful is meant to be adapted across Germany.