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BACKGROUND: For the implantation of pedicle screws, navigation-supported systems are nowadays used more and more to avoid screw misalignment by making the direction of the screw more predictable. OBJECTIVE: Examination of the precision after instrumentation of the pedicle screw with the hand-guided aiming sleeve. The aim was to verify that the implementation of the pedicle screws is plannable and precise by using 2D X­ray only. METHOD: This retrospective study analyzed 27 consecutive trauma patients (17-84 years, 13f/14m) with vertebral body fractures. The position and precision of 108 screws, implanted using the hand-guided aiming sleeve was investigated. To determine the position the actual course of the screws was examined using the postoperative 3D CT data set (GE Optima 540, General Electric Company Boston, MA, USA; slice thickness 1.25 mm). The screws were then compared to the previously defined ideal position of the tip of the screw. In addition to the absolute and relative deviation from the ideal target point, the convergence angle and the parallelism to the cover plate were determined. RESULTS: Of 108 implanted pedicle screws, 90 (83%) were within target. The remaining 18 (17%) represented a clinically irrelevant screw deviation: A lateral deviation was found in 17 pedicle screws (16%) and a medial deviation in 1 (1%). The average deviation from the ideal target point in the vertebral body was 2.3 mm ventrally with a standard deviation of ±â€¯2.3 mm. No screw misalignment or pedicle perforation was found. CONCLUSION: The transcutaneous implantation of pedicle screws with a hand-guided aiming sleeve in the thoracic and lumbar spine represents a safe and precise procedure. The risk of misalignment needing a revision is lower compared to other methods of navigated screw implantation reported in the literature [1-6]. A CT-based preliminary planning is not necessary. The method is economical, special technical equipment is not required.

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Anticipating changes to vehicle interiors with future automated driving systems, the automobile industry recently has focused attention on crash response in novel postures with increased seatback recline. Prior research found that this posture may result in greater risk of lumbar spine injury in the event of a frontal crash. This study developed a lumbar spine injury risk function (IRF) that estimated injury risk as a function of simultaneously applied compression force and flexion moment. Force and moment failure data from 40 compression-flexion tests were utilized in a Weibull survival model, including appropriate data censoring. A mechanics-based injury metric was formulated, where lumbar spine compression force and flexion moment were normalized by specimen geometry. Subject age was incorporated as a covariate to further improve model fit. A weighting factor was included to adjust the influence of force and moment, and parameter optimization yielded a value of 0.11. Thus, the normalized compression force component had a greater effect on injury risk than the normalized flexion moment component. Additionally, as force was nominally increased, less moment was required to produce injury for a given age and specimen geometry. The resulting IRF may be utilized to improve occupant safety in the future.

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BACKGROUND: Traumatic injuries of the cervical spine are common and can significantly differ in the prognosis and treatment depending on the structure affected. We present the current evidence for conservative treatment of these fractures with orthoses in this review. METHODOLOGY: The literature search followed the PRISMA protocol. The risk of bias was assessed using ROBINS­I and evidence levels were determined according to AHCPR. RESULTS: A total of 22 studies were identified. The level of evidence according to AHCPR is limited (IIb, III and IV) and every study had a serious risk of bias in at least one subdivision. Of the authors 11 presented conservative treatment concepts for C2 dens fractures, 7 studies focussed on vertebral arch fractures and 9 on vertebral body fractures. Radiological parameters (kyphosis angle, bone consolidation) and the neurological status were frequently reported as endpoints. CONCLUSION: Stable C2 dens fractures without relevant clinical restrictions allow conservative treatment in a rigid cervical orthosis under radiological monitoring every 1-4 weeks. Type II fractures require special attention due to the risk of instability. Hangman's fractures can be safely treated in rigid cervical orthoses. The current state of knowledge does not allow any recommendation for conservative treatment of Hangman's fractures with orthoses. Stable vertebral body fractures without involvement of the spinal canal can also be treated conservatively with orthotic devices. Randomized controlled studies are required to develop a secure state of evidence and are currently not available.

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OBJECTIVES: The purpose of this study was to investigate whether the addition of computed tomography (CT) to magnetic resonance imaging (MRI) improves the accuracy of classifying osteoporotic vertebral body fractures (OVBF). METHODS: A retrospective analysis of a prospective single-center database has been performed. All consecutive patients who had suffered an acute thoracolumbar OVBF in one level II spine center between 2017 and 2019 were analyzed. Thereby, fractures of type OF 1 and OF 5 were excluded. All fractures were initially classified by 5 board-certified orthopaedic surgeons based on MRI and conventional radiographs. Afterwards a reclassification including CT scans were performed. Differences in OF classification and OF score values between both measurements were analyzed. RESULTS: A total of 61 patients were analyzed with a mean age 75.8 years (SD: 8.8 years). In 82.9% of the cases, there was no difference in OF classification comparing classification based only on MRI versus MRI + CT. A difference of more than two OF types was observed in less than 1% of all ratings. The inter-rater reliabilities of the OF classification based on CT + MRI and MRI alone were 0.63 and 0.49, respectively. In 97.5% of the cases there was no therapy-relevant difference of the treatment recommendation with respect of a surgical or nonoperative treatment recommendation based on the OF score. CONCLUSION: In terms of the OF classification and the OF score, the addition of CT add limited value compared to conventional radiographs and MRI only. Additionally, there is only a minor rate of disagreement in treatment recommendations when adding a CT.

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PURPOSE: The purpose of this study was analyzing the effect of subsequent vertebral body fractures on the clinical outcome in geriatric patients with thoracolumbar fractures treated operatively. METHODS: Retrospectively, all patients aged ≥ 60 with a fracture of the thoracolumbar spine included. Further inclusion parameters were acute and unstable fractures that were treated by posterior stabilization with a low to moderate loss of reduction of less than 10°. The minimal follow-up period was 18 months. Demographic data including the trauma mechanism, ASA score, and the treatment strategy were recorded. The following outcome parameters were analyzed: the ODI score, pain level, satisfaction level, SF 36 score as well as the radiologic outcome parameters. RESULTS: Altogether, 73 patients were included (mean age: 72 years; 45 women). The majority of fractures consisted of incomplete or complete burst fractures (OF 3 + 4). The mean follow-up period was 46.6 months. Fourteen patients suffered from subsequent vertebral body fractures (19.2%). No trauma was recordable in 5 out of 6 patients; 42.8% of patients experienced a low-energy trauma (significant association: p < 0.01). There was a significant correlation between subsequent vertebral body fracture and female gender (p = 0.01) as well as the amount of loss of reduction (p = 0.02). Thereby, patients with subsequent vertebral fractures had significant worse clinical outcomes (ODI: 49.8 vs 16.6, p < 0.01; VAS pain: 5.0 vs 2.6, p < 0.01). CONCLUSION: Patient with subsequent vertebral body fractures had significantly inferior clinical midterm outcome. The trauma mechanism correlated significantly with both the rate of subsequent vertebral body fractures and the outcome. Another risk factor is female gender.

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PURPOSE: The aim of this systematically review is to detect differences between fractures located at the mid-thoracic spine compared to fractures of the thoracolumbar junction (TLJ) and the lumbar spine in osteoporotic vertebral body fractures. METHODS: This review is based on articles retrieved by a systematic search in the PubMed and Web of Science database for publications regarding osteoporotic fractures of the thoracolumbar spine with respect to the fracture location. Differences in prevalence, cause of fracture, fracture healing, and outcomes between the mid-thoracic spine and the TLJ and the lumbar spine were considered. RESULTS: Altogether, 238 articles could be retrieved from the literature search. A total of 222 articles were excluded. Thus, 16 remaining original articles were included in this systematic review comprising the topics prevalence, bone mineral density and regional blood flow, biomechanics, subsequent fractures, and outcome, respectively. The overall level of evidence of the vast majority of studies was moderate to low. CONCLUSION: Several differences between osteoporotic fractures of the mid-thoracic spine compared to the TLJ and the lumbar spine could be identified. Thereby, osteoporotic mid-thoracic fractures seem to be particularly more related to frailty without a history of traumatic injury compared to osteoporotic fractures of the TLJ and the lumbar spine. Additionally, the presence of severe mid-thoracic fractures predicts subsequent fractures of the hip. In contrast, subsequent fractures of the spine are less likely.

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PURPOSE: Basivertebral foramina (BVF) are openings of the posterior wall of vertebral body (VB) that lead to basivertebral canals (BVC), where homonymous neurovascular bundle courses. BVF and BVC are implicated with spinal fractures, vertebral augmentation and basivertebral nerve radiofrequency ablation. Despite their essential clinical impact, knowledge of BVF precise anatomy is scarce. The current study describes in detail the BVF typical morphological and topographical anatomy, morphometry and variants. METHODS: In total, 1561 dried true vertebrae of 70 Greek spines of known gender and age were examined. BVF number, location, shape and size (in foramina > 1 mm), BVF distance from VB rims and pedicles, as well as VB morphometry (diameters, heights and distance between pedicles) were studied. Ten spines were re-examined by computed tomography and BVC depth and shape were recorded. Correlations and differences were statistically analyzed. RESULTS: C1 lack BVF (3.4%). One BVF was found in 45.1%, two in 36.9%, three in 3.8% and four BVF in 0.6%. Multiple small (< 1 mm) foramina were observed in 10.1%. Asymmetry was detected in 12.3%. C2 and T10-L1 presented typical pattern, whereas C3 and T2 had the greatest variability. BVF were significantly closer to the upper rim in C2 and T10-L4 and to the lower rim in C7-T4, T6-T8 and L5. The mean BVC depth was 12-21.8% of the VB anteroposterior diameter. CONCLUSION: BVF number, shape, size and topography are described, in detail, per vertebral level. The provided morphological classification and the created cumulative BVF topographic graphs should assist in clinical practice and surgery.

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PURPOSE: To evaluate the safety and efficacy of a novel augmentation implant in the treatment of patients with symptomatic vertebral body fractures. MATERIALS AND METHODS: Thirty consecutive patients (seven males and 23 females), mean age of 70 years (range 56 to 89) with osteoporotic fractures and/or low-energy trauma fractures (osteoporosis confirmed by CT), were enrolled in an IRB-approved prospective study. The type of fracture was classified according to the Magerl classification. The patients were treated with the Tektona® dedicated vertebral body augmentation system. Visual analogue scale (VAS) and Oswestry Disability Index (ODI) scores were obtained after 1, 6 and 12 months. Quality of life was assessed with the SF36 score. RESULTS: A total of 37 vertebral bodies, mostly from T6 to L5, were treated in the 30 enrolled patients. In 67.6% of the cases (n = 25), lumbar fractures were treated. Most of the fractures (43%; n = 16) were A1.1 according to the Magerl classification. A significant pain reduction evaluated by VAS scores (p < 0.0001) was observed on average 7.6 (before the procedure) to 2.8 (immediately post-treatment), 2.1 and 2.7 (after 6 and 12 months later, respectively). The mean ODI score was 55.5% before treatment, and this was statistically significant reduced to 22.3% and 26.9%, respectively, at 6 and 12 months after treatment (p < 0.0001). The SF36 scores, both physical and mental components, showed statistically significant variations (p < 0.0001) whose direction was subpopulation dependent. CONCLUSION: Patients with confirmed osteoporosis, suffering from symptomatic vertebral body fractures (osteoporotic and/or low-energy traumatic), were treated safely and effectively using this novel implant.

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STUDY DESIGN: consensus paper with systematic literature review. OBJECTIVE: The aim of this study was to establish recommendations for treatment of thoracolumbar spine fractures based on systematic review of current literature and consensus of several spine surgery experts. METHODS: The project was initiated in September 2008 and published in Germany in 2011. It was redone in 2017 based on systematic literature review, including new AOSpine classification. Members of the expert group were recruited from all over Germany working in hospitals of all levels of care. In total, the consensus process included 9 meetings and 20 hours of video conferences. RESULTS: As regards existing studies with highest level of evidence, a clear recommendation regarding treatment (operative vs conservative) or regarding type of surgery (posterior vs anterior vs combined anterior-posterior) cannot be given. Treatment has to be indicated individually based on clinical presentation, general condition of the patient, and radiological parameters. The following specific parameters have to be regarded and are proposed as morphological modifiers in addition to AOSpine classification: sagittal and coronal alignment of spine, degree of vertebral body destruction, stenosis of spinal canal, and intervertebral disc lesion. Meanwhile, the recommendations are used as standard algorithm in many German spine clinics and trauma centers. CONCLUSION: Clinical presentation and general condition of the patient are basic requirements for decision making. Additionally, treatment recommendations offer the physician a standardized, reproducible, and in Germany commonly accepted algorithm based on AOSpine classification and 4 morphological modifiers.

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PURPOSE: To test the diagnostic performance of susceptibility-weighted MRI (sMRI) for the evaluation of vertebral body fractures versus standard MRI-sequences, using CT as reference standard. METHODS: In this prospective study 88 vertebral fractures (45 healed, 43 non-healed) were detected in 39 patients who underwent T1/T2/TIRM MRI-sequences and sMRI. All fractures were evaluated with CT as reference standard. In all modalities/sequences, displacement and height of the posterior vertebral body cortex and visibility of fracture lines and cortical breaks were assessed. Sensitivity, specificity and inter-reader agreement between MRI and CT were calculated. RESULTS: sMRI demonstrated highest diagnostic accuracy for detection of posterior vertebral body cortex involvement (sensitivity: 98 %/specificity: 100 %), fracture lines (86 %/99 %) and cortical breaks (93 %/100 %) versus T1/T2/TIRM sequences. Regarding evaluation of posterior vertebral body cortex displacement and height, sMRI demonstrated the closest intermodality agreement (R2=0.96; 95 % CI -0.92-0.89/R2=0.97; 95 % CI -1.67-1.23) with CT and the closest interobserver agreement (R2=0.97; 95 % CI -0.71-1.01). CONCLUSION: sMRI allows reliable evaluation of vertebral body fractures with regard to posterior vertebral body cortex displacement and height, cortical breaks and fracture lines with higher accuracy versus standard MRI, especially in patients with non-healed vertebral body fractures. KEY POINTS: • sMRI allows a reliable evaluation of vertebral body fractures. • sMRI has higher accuracy than standard-MRI for evaluation of vertebral body fractures. • sMRI is especially useful in patients with non-healed vertebral body fractures.

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BACKGROUND: Vertebral body fractures (VBF) can be caused by various trauma mechanisms. The AOSpine classification system differentiates three main types of fractures according to the grade of instability. How the increasing energy of various accident mechanisms changes the complexity of the individual fracture, its localization and the occurrence of further fractures has not yet been finally investigated. OBJECTIVE: What influence do traumatic events with different kinematics have on the localization, complexity and number of VBF in the thoracic and lumbar spine? MATERIAL AND METHODS: In this retrospective study data from patients with a freshly traumatized VBF were analyzed. The patients were divided into six trauma groups (UFG) depending on the trauma mechanism. The VBF were classified on the basis of computed tomography (CT) imaging according to the AOSpine classification system. Testing was performed bilaterally and a significance level of 5% was used. The statistical calculations were carried out using IBM SPSS Statistics. RESULTS: A significant increase in the severity of fractures (AO classification) was found in the high energy trauma groups (UFG III and V). In addition, the incidence of thoracic (TH) VBF was significantly increased for TH7 (p = 0.011) and TH10 (p = 0.001). In comparison to the other low energy trauma groups, the risk of a TH7 fracture was 7­times higher after a high energy trauma (odds ratio OR = 7.0; 95% confidence interval CI = 1.4; 35.2). The UFG III (falls > 3 m) showed the highest number of fractures with a median of 2.5 (SD 1.84) VBF. CONCLUSION: An exact reproduction of the traumatic event enables a distinction between high and low energy trauma groups to be made. In previous studies traffic accidents were recorded as one group, so an influence of the increasing kinematic energy could not be assessed. The accident kinematics can be taken into account by differentiating between high and low-energy trauma groups. In high-energy accidents the TH7 and TH10 vertebrae were found to be at risk vertebrae. In addition to the force direction, the force strength also has a decisive influence on the distribution pattern of VBF.

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