The spinal cord injury-induced immune deficiency syndrome: results of the SCIentinel study.

Infections are prevalent after spinal cord injury (SCI), constitute the main cause of death and are a rehabilitation confounder associated with impaired recovery. We hypothesize that SCI causes an acquired lesion-dependent (neurogenic) immune suppression as an underlying mechanism to facilitate infections. The international prospective multicentre cohort study (SCIentinel; protocol registration DRKS00000122; n = 111 patients) was designed to distinguish neurogenic from general trauma-related effects on the immune system. Therefore, SCI patient groups differing by neurological level, i.e. high SCI [thoracic (Th)4 or higher]; low SCI (Th5 or lower) and severity (complete SCI; incomplete SCI), were compared with a reference group of vertebral fracture (VF) patients without SCI. The primary outcome was quantitative monocytic Human Leukocyte Antigen-DR expression (mHLA-DR, synonym MHC II), a validated marker for immune suppression in critically ill patients associated with infection susceptibility. mHLA-DR was assessed from Day 1 to 10 weeks after injury by applying standardized flow cytometry procedures. Secondary outcomes were leucocyte subpopulation counts, serum immunoglobulin levels and clinically defined infections. Linear mixed models with multiple imputation were applied to evaluate group differences of logarithmic-transformed parameters. Mean quantitative mHLA-DR [ln (antibodies/cell)] levels at the primary end point 84 h after injury indicated an immune suppressive state below the normative values of 9.62 in all groups, which further differed in its dimension by neurological level: high SCI [8.95 (98.3% confidence interval, CI: 8.63; 9.26), n = 41], low SCI [9.05 (98.3% CI: 8.73; 9.36), n = 29], and VF without SCI [9.25 (98.3% CI: 8.97; 9.53), n = 41, P = 0.003]. Post hoc analysis accounting for SCI severity revealed the strongest mHLA-DR decrease [8.79 (95% CI: 8.50; 9.08)] in the complete, high SCI group, further demonstrating delayed mHLA-DR recovery [9.08 (95% CI: 8.82; 9.38)] and showing a difference from the VF controls of -0.43 (95% CI: -0.66; -0.20) at 14 days. Complete, high SCI patients also revealed constantly lower serum immunoglobulin G [-0.27 (95% CI: -0.45; -0.10)] and immunoglobulin A [-0.25 (95% CI: -0.49; -0.01)] levels [ln (g/l × 1000)] up to 10 weeks after injury. Low mHLA-DR levels in the range of borderline immunoparalysis (below 9.21) were positively associated with the occurrence and earlier onset of infections, which is consistent with results from studies on stroke or major surgery. Spinal cord injured patients can acquire a secondary, neurogenic immune deficiency syndrome characterized by reduced mHLA-DR expression and relative hypogammaglobulinaemia (combined cellular and humoral immune deficiency). mHLA-DR expression provides a basis to stratify infection-risk in patients with SCI.

[Resuscitation room diagnostics]. / Schockraumdiagnostik.

CLINICAL PROBLEM: The indication for resuscitation room care is an acute (potentially) life-threatening patient condition. Typical causes for this are polytrauma, acute neurological symptoms, acute chest and abdominal pain or the cause remains unclear at first. The care is always provided in a suitably composed interdisciplinary team. This requires cause-specific standards tailored to the care facility and requires a mutual understanding of the partners involved with regard to specialist interests and care processes. STANDARD RADIOLOGICAL METHODS: Whole-body CT is established for polytrauma imaging and usually each institution has already defined an institutional standard. For the other causes, first imaging with CT is just as common, but the protocols and procedures to be used are often not as clear as in the case of polytrauma. METHODICAL INNOVATION AND EVALUATION: For polytrauma service, ATLS and procedures according to ABCDE already serve as a largely standardized framework in the resuscitation room. For every other group of causes, comparable concepts should be developed and institutionally strive for objectification of continuous improvement. This refers not only to the resuscitation room stay but also to the interfaces before and after resuscitation room service. PRACTICAL RECOMMENDATIONS: After the patient has arrived, it has to be determined whether the assessment of a vital risk is retained. If so, institutionally defined care standards must be followed for the various causes. This concerns the interface logistics, the definition of a team leader including associated tasks, the supply processes including the CT examination protocols as well as the close communication.

An Integrated Clinico-transcriptomic Approach Identifies a Central Role of the Heme Degradation Pathway for Septic Complications after Trauma.

OBJECTIVE: The present study was aimed to identify mechanisms linked to complicated courses and adverse events after severe trauma by a systems biology approach. SUMMARY BACKGROUND DATA: In severe trauma, overwhelming systemic inflammation can result in additional damage and the development of complications, including sepsis. METHODS: In a prospective, longitudinal single-center study, RNA samples from circulating leukocytes from patients with multiple injury (injury severity score ≥17 points; n = 81) were analyzed for dynamic changes in gene expression over a period of 21 days by whole-genome screening (discovery set; n = 10 patients; 90 samples) and quantitative RT-PCR (validation set; n = 71 patients, 517 samples). Multivariate correlational analysis of transcripts and clinical parameters was used to identify mechanisms related to sepsis. RESULTS: Transcriptome profiling of the discovery set revealed the strongest changes between patients with either systemic inflammation or sepsis in gene expression of the heme degradation pathway. Using quantitative RT-PCR analyses (validation set), the key components haptoglobin (HP), cluster of differentiation (CD) 163, heme oxygenase-1 (HMOX1), and biliverdin reductase A (BLVRA) showed robust changes following trauma. Upregulation of HP was associated with the severity of systemic inflammation and the development of sepsis. Patients who received allogeneic blood transfusions had a higher incidence of nosocomial infections and sepsis, and the amount of blood transfusion as source of free heme correlated with the expression pattern of HP. CONCLUSIONS: These findings indicate that the heme degradation pathway is associated with increased susceptibility to septic complications after trauma, which is indicated by HP expression in particular.

Direct transplantation of native pericytes from adipose tissue: A new perspective to stimulate healing in critical size bone defects.

BACKGROUND AIMS: Fractures with a critical size bone defect (e.g., open fracture with segmental bone loss) are associated with high rates of delayed union and non-union. The prevention and treatment of these complications remain a serious issue in trauma and orthopaedic surgery. Autologous cancellous bone grafting is a well-established and widely used technique. However, it has drawbacks related to availability, increased morbidity and insufficient efficacy. Mesenchymal stromal cells can potentially be used to improve fracture healing. In particular, human fat tissue has been identified as a good source of multilineage adipose-derived stem cells, which can be differentiated into osteoblasts. The main issue is that mesenchymal stromal cells are a heterogeneous population of progenitors and lineage-committed cells harboring a broad range of regenerative properties. This heterogeneity is also mirrored in the differentiation potential of these cells. In the present study, we sought to test the possibility to enrich defined subpopulations of stem/progenitor cells for direct therapeutic application without requiring an in vitro expansion. METHODS: We enriched a CD146+NG2+CD45- population of pericytes from freshly isolated stromal vascular fraction from mouse fat tissue and tested their osteogenic differentiation capacity in vitro and in vivo in a mouse model for critical size bone injury. RESULTS: Our results confirm the ability of enriched CD146+NG2+CD45- cells to efficiently generate osteoblasts in vitro, to colonize cancellous bone scaffolds and to successfully contribute to regeneration of large bone defects in vivo. CONCLUSIONS: This study represents proof of principle for the direct use of enriched populations of cells with stem/progenitor identity for therapeutic applications.

Implementation of a patient blood management monitoring and feedback program significantly reduces transfusions and costs.

BACKGROUND: Patient blood management (PBM) measures have been shown to be effective in reducing transfusions while maintaining patient outcome. The issuance of transfusion guidelines is seen as being key to the success of PBM programs. As the introduction of guidelines alone did not visibly reduce transfusions in our center, a monitoring and feedback program was established. The aim of our study was to show the effectiveness of such measures in reducing transfusions and cost. STUDY DESIGN AND METHODS: We designed a prospective, interventional cohort study with a 3-year time frame (January 1, 2012 to December 31, 2014). In total, 101,794 patients aged 18 years or older were included. The PBM monitoring and feedback program was introduced on January 1, 2014, with the subsequent issuance of quarterly reporting. RESULTS: Within the first year of introduction, transfusion of all allogeneic blood products per 1000 patients was reduced by 27% (red blood cell units, -24%; platelet units, -25%; and fresh-frozen plasma units, -37%; all p < 0.001) leading to direct allogeneic blood product related savings of more than 2 million USD. The number of blood products transfused per case was significantly reduced from 9 ± 19 to 7 ± 14 (p < 0.001). With an odds ratio of 0.86 (95% confidence interval, 0.82-0.91), the introduction of our PBM monitoring and feedback program was a significant independent factor in the reduction of transfusion probability (p < 0.001). CONCLUSION: Our PBM monitoring and feedback program was highly efficacious in reducing the transfusion of allogeneic blood products and transfusion-related costs.

Improvement of prognostic performance in severely injured patients by integrated clinico-transcriptomics: a translational approach.

INTRODUCTION: Severe trauma triggers a systemic inflammatory response that contributes to secondary complications, such as nosocomial infections, sepsis or multi-organ failure. The present study was aimed to identify markers predicting complications and an adverse outcome of severely injured patients by an integrated clinico-transcriptomic approach. METHODS: In a prospective study, RNA samples from circulating leukocytes from severely injured patients (injury severity score ≥ 17 points; n = 104) admitted to a Level I Trauma Center were analyzed for dynamic changes in gene expression over a period of 21 days by quantitative RT-PCR. Transcriptomic candidates were selected based on whole genome screening of a representative discovery set (n = 10 patients) or known mechanisms of the immune response, including mediators of inflammation (IL-8, IL-10, TNF-α, MIF, C5, CD59, SPHK1), danger signaling (HMGB1, TLR2, CD14, IL-33, IL-1RL1), and components of the heme degradation pathway (HP, CD163, HMOX1, BLVRA, BLVRB). Clinical markers comprised standard physiological and laboratory parameters and scoring systems routinely determined in trauma patients. RESULTS: Leukocytes, thrombocytes and the expression of sphingosine kinase-1 (SPHK1), complement C5, and haptoglobin (HP) have been identified as markers with the best performance. Leukocytes showed a biphasic course with peaks on day 0 and day 11 after trauma, and patients with sepsis exhibited significantly higher leukocyte levels. Thrombocyte numbers showed a typical profile with initial thrombopenia and robust thrombocytosis in week 3 after trauma, ranging 2- to 3-fold above the upper normal value. 'Relative thrombocytopenia' was associated with multi-organ dysfunction, the development of sepsis, and mortality, the latter of which could be predicted within 3 days prior to the time point of death. SPHK1 expression at the day of admission indicated mortality with excellent performance. C5-expression on day 1 after trauma correlated with an increased risk for the development of nosocomial infections during the later course, while HP was found to be a marker for the development of sepsis. CONCLUSIONS: The combination of clinical and transcriptomic markers improves the prognostic performance and may represent a useful tool for individual risk stratification in trauma patients.

Mechanical testing of a device for subcutaneous internal anterior pelvic ring fixation versus external pelvic ring fixation.

BACKGROUND: Although useful in the emergency treatment of pelvic ring injuries, external fixation is associated with pin tract infections, the patient's limited mobility and a restricted surgical accessibility to the lower abdomen. In this study, the mechanical stability of a subcutaneous internal anterior fixation (SIAF) system is investigated. METHODS: A standard external fixation and a SIAF system were tested on pairs of Polyoxymethylene testing cylinders using a universal testing machine. Each specimen was subjected to a total of 2000 consecutive cyclic loadings at 1 Hz with sinusoidal lateral compression/distraction (+/-50 N) and torque (+/- 0.5 Nm) loading alternating every 200 cycles. Translational and rotational stiffness were determined at 100, 300, 500, 700 and 900 cycles. RESULTS: There was no significant difference in translational stiffness between the SIAF and the standard external fixation when compared at 500 (p = .089), 700 (p = .081), and 900 (p = .266) cycles. Rotational stiffness observed for the SIAF was about 50 percent higher than the standard external fixation at 300 (p = .005), 500 (p = .020), and 900 (p = .005) cycles. No loosening or failure of the rod-pin/rod-screw interfaces was seen. CONCLUSIONS: In comparison with the standard external fixation system, the tested device for subcutaneous internal anterior fixation (SIAF) in vitro has similar translational and superior rotational stiffness.

Effect of elevated serum alcohol level on the outcome of severely injured patients.

BACKGROUND: The influence of high blood alcohol level (BAL) on the outcome of severely injured patients and the corresponding pathophysiological changes is a controversial issue. OBJECTIVE: To carry out a prognostic study to compare the physiological values and short-term outcome of severely injured patients depending on their serum alcohol level. METHODS: A total of 383 severely injured patients with an Injury Severity Score (ISS) ≥17 were admitted to the trauma division between October 2008 and December 2009 and enrolled into this study. Patients were grouped according to their BAL (>0.5‰,'BAL positive' vs <0.5‰,'BAL negative'). Trauma mechanism, pattern of injury and its treatment, and a course of intensive care treatment, physiological parameters and outcome with respect to mortality were analysed. RESULTS: Both groups had similar ISS. In comparison with the BAL-negative group, patients in the BAL-positive group had a significantly lower Glasgow Coma Scale score (9.64 vs 12 points; p=0.005) and, although not significant, a trend towards higher values of the Abbreviated Injury Score for the head (3.29 vs 2.81 points; p=0.146). Furthermore, significantly higher lactate (3.11 mmol/L vs 2.02 mmol/L; p<0.001) levels and lower median arterial pressure values (87.9 mm Hg vs 99.4 mm Hg; p=0.006) were seen in the BAL-positive group at day of admission. However, the overall in-hospital mortality was comparable to that in BAL-negative patients (19.6% vs 21.5%). Similarly, hospital stay (15.29 vs 17.55 days) and duration of intensive care unit treatment (8.53 vs 8.36 days) were not significantly affected by a high BAL upon admission. CONCLUSIONS: Severely injured patients with a raised BAL have a higher incidence of severe traumatic brain injury and worse initial physiological parameters. However, the survival rate and in-hospital stay is not influenced. This supports the theory of a neuroprotective role of alcohol.

Characterization of indeterminate spleen lesions in primary CT after blunt abdominal trauma: potential role of MR imaging.

The purpose of this study was to determine the value of magnetic resonance imaging (MRI) for characterization of indeterminate spleen lesions in primary computed tomography (CT) of patients with blunt abdominal trauma. Twenty-five consecutive patients (8 female, 17 male, mean age 51.6 ± 22.4 years) with an indeterminate spleen lesion diagnosed at CT after blunt abdominal trauma underwent MRI with T2- and T1-weighted images pre- and post-contrast material administration. MRI studies were reviewed by two radiologists. Age, gender, injury mechanism, injury severity score (ISS), management of patients, time interval between CT and MRI, and length of hospital stay were included into the analysis. Patient history, clinical history, imaging, and 2-month clinical outcome including review of medical records and telephone interviews served as reference standard. From the 25 indeterminate spleen lesions in CT, 11 (44 %) were traumatic; nine (36 %) were non-traumatic (pseudocysts, n=5; hemangioma, n=4) and five proven to represent artifacts in CT. The ISS (P<0.001) and the length of hospital stay (P=0.03) were significantly higher in patients with spleen lesions as compared with those without. All other parameters were similar among groups (all, P>0.05). The MRI features ill-defined lesion borders, variable signal intensity on T1- and T2-weighted images depending on the age of the hematoma, focal contrast enhancement indicating traumatic pseudoaneurysm, perilesional contrast enhancement, and edema were most indicative for traumatic spleen lesions. As compared with CT (2/25), MRI (5/25) better depicted thin subcapsular hematomas as indicator of traumatic spleen injury. In conclusion, MRI shows value for characterizing indeterminate spleen lesions in primary CT after blunt abdominal trauma.

The role of big data management, data registries, and machine learning algorithms for optimizing safe definitive surgery in trauma: a review.

Digital data processing has revolutionized medical documentation and enabled the aggregation of patient data across hospitals. Initiatives such as those from the AO Foundation about fracture treatment (AO Sammelstudie, 1986), the Major Trauma Outcome Study (MTOS) about survival, and the Trauma Audit and Research Network (TARN) pioneered multi-hospital data collection. Large trauma registries, like the German Trauma Registry (TR-DGU) helped improve evidence levels but were still constrained by predefined data sets and limited physiological parameters. The improvement in the understanding of pathophysiological reactions substantiated that decision making about fracture care led to development of patient's tailored dynamic approaches like the Safe Definitive Surgery algorithm. In the future, artificial intelligence (AI) may provide further steps by potentially transforming fracture recognition and/or outcome prediction. The evolution towards flexible decision making and AI-driven innovations may be of further help. The current manuscript summarizes the development of big data from local databases and subsequent trauma registries to AI-based algorithms, such as Parkland Trauma Mortality Index and the IBM Watson Pathway Explorer.

Augmented reality-based surgical navigation of pelvic screw placement: an ex-vivo experimental feasibility study.

BACKGROUND: Minimally invasive surgical treatment of pelvic trauma requires a significant level of surgical training and technical expertise. Novel imaging and navigation technologies have always driven surgical technique, and with head-mounted displays being commercially available nowadays, the assessment of such Augmented Reality (AR) devices in a specific surgical setting is appropriate. METHODS: In this ex-vivo feasibility study, an AR-based surgical navigation system was assessed in a specific clinical scenario with standard pelvic and acetabular screw pathways. The system has the following components: an optical-see-through Head Mounted Display, a specifically designed modular AR software, and surgical tool tracking using pose estimation with synthetic square markers. RESULTS: The success rate for entry point navigation was 93.8%, the overall translational deviation of drill pathways was 3.99 ± 1.77 mm, and the overall rotational deviation of drill pathways was 4.3 ± 1.8°. There was no relevant theoretic screw perforation, as shown by 88.7% Grade 0-1 and 100% Grade 0-2 rating in our pelvic screw perforation score. Regarding screw length, 103 ± 8% of the planned pathway length could be realized successfully. CONCLUSION: The novel innovative system assessed in this experimental study provided proof-of-concept for the feasibility of percutaneous screw placement in the pelvis and, thus, could easily be adapted to a specific clinical scenario. The system showed comparable performance with other computer-aided solutions while providing specific advantages such as true 3D vision without intraoperative radiation; however, it needs further improvement and must still undergo regulatory body approval. Future endeavors include intraoperative registration and optimized tool tracking.

Fracture fixation in polytraumatized patients-From an interdisciplinary early total/appropriate care to the safe definitive surgery concept.

The strategies for the timing of fracture fixation in polytrauma patients have changed with improvements in resuscitation and patient assessment. Specifically, the criteria for damage control have been formulated, and more precise parameters have been found to determine those patients who can safely undergo primary definitive fixation of major fractures. Our current recommendations are supported by objective and data-based criteria and development groups. Those were validated and compared to existing scores. This review article introduces the concept of "safe definitive surgery" and provides an update on the parameters used to clear patients for timely fixation of major fractures.

3D-navigation for SI screw fixation - How does it affect radiation exposure for patients and medical personnel?

BACKGROUND: 3D-navigation for percutaneous sacroiliac (SI) screw fixation is becoming increasingly common and several studies report great advantages of this technology. However, there is still limited clinical evidence on the efficacy regarding radiation exposure for patient and personnel. METHODS: This is a retrospective, single-center cohort study. All patients who underwent percutaneous sacroiliac screw fixation for an injury of the posterior pelvic ring from 2014 to 2021 were screened. Inclusion criteria were: conclusive radiation dosage reports, signed informed consent, a twelve month follow up and a complete data set. Patients were stratified in two groups (3D-navigation (Group 3D-N) vs. control (Group F)) based on the imaging modality used. Primary outcomes were radiation exposure for patient and personnel. Secondary outcomes were reoperations, complications, and intraoperative precision. RESULTS: Of 392 patients screened, 174 patients (3D-N: n = 50, F: n = 124) could be included for final analysis. We noted a significant reduction of the dose corresponding to potential radiation exposure for medical personnel (-15.3 mGy, 95 %CI: -2.1 to -28.5, p = 0.0232), but also a significant increase of the dose quantifying radiation exposure for patients (+77.0 mGy, 95 %CI: +53.3 to +100.6, p < 0.0001), when using navigation. In addition, the rate of radiographic malplacement was significantly reduced (F: 11.3% vs. 3D-N: 0 %, p = 0.0113) despite a substantial increase in transsacral screw placement (F: 19.4% vs. 3D-N: 76 %). CONCLUSION: Our data clearly suggests that the use of 3D-navigation for percutaneous SI screw fixation decreases radiation exposure for medical personnel, while increasing radiation exposure for patients. Furthermore, intraoperative precision is improved, even in more challenging operations.

Effects of vitamin D3, omega-3 s and a simple strength training exercise program on bone health: the DO-HEALTH randomized controlled trial.

INTRODUCTION: Evidence on the effects of Vitamin D, omega-3 s and exercise on aBMD in healthy older adults is limited. We examined whether vitamin D3, omega-3 s, or a simple home-based exercise program (SHEP), alone or in combination, over three years, improve lumbar spine (LS), femoral neck (FN) or total hip (TH) aBMD assessed by DXA. METHODS: aBMD was a secondary outcome in DO-HEALTH, a 3-year, multicenter, double-blind, randomized 2 × 2 × 2 factorial design trial in generally healthy older adults age ≥ 70 years. The study interventions were vitamin D3 (2000IU/d), omega-3 s (1 g/d), and SHEP (3 × 30 min/wk), applied alone or in combination in 8 treatment arms. Mixed effect models were used adjusting for age, sex, BMI, prior fall, study site and baseline level of the outcome. Main effects were assessed in the absence of an interaction between the interventions. Subgroup analyses by sex, physical activity level, dietary calcium intake, serum 25(OH)D levels, and fracture history were conducted. RESULTS: DXA scans were available for 1493 participants (mean age 75 years; 80.4% were physically active, 44% had 25(OH)D levels <20 ng/ml). At the LS and FN sites, none of the treatments showed a benefit. At the TH, vitamin D vs. no vitamin D treatment showed a significant benefit across 3 years (difference in adjusted means [AM]: 0.0035 [95% CI 0.0011, 0.0059] g/cm2). Furthermore, there was a benefit for vitamin D vs. no vitamin D treatment on LS aBMD in the male subgroup of (interaction P = 0.003; ∆AM: 0.0070 [95% CI 0.0007, 0.0132] g/cm2). CONCLUSIONS: Omega-3 and SHEP had no benefit on aBMD in healthy, active and largely vitamin D replete older adults. Our study suggests a small benefit of 2000 IU vitamin D daily on TH aBMD overall and LS aBMD among men, however, effect sizes were very modest and the clinical impact of these findings is unclear.

Vitamin D, omega-3 fatty acids (omega-3 s) and strength training are simple but promising strategies to improve bone health, however, their effect in healthy older adults over a period of three years was unclear. In this study, we examined whether daily vitamin D supplementation (2000 IU/d), daily omega-3 s supplementation (1 g/d) or a simple strength training program performed three times per week, either applied alone (e.g., only vitamin D supplements) or in combination (e.g., vitamin D and omega-3 s supplements) could improve bone density at the spine, hip or femoral neck. We included 1493 healthy older adults from Switzerland, Germany, France and Portugal who were at least 70 years of age and who had not experienced any major health events in the five years before study start. Taking omega-3 s supplements showed no benefit for bone density. Similarly, the simple strength exercise program showed no benefit. In contrast, participants receiving daily vitamin D supplements experienced a benefit at the hip. However, it should be noted that the effect across three years was very small.

Reduction of metal artifacts from hip prostheses on CT images of the pelvis: value of iterative reconstructions.

PURPOSE: To assess the value of iterative frequency split-normalized (IFS) metal artifact reduction (MAR) for computed tomography (CT) of hip prostheses. MATERIALS AND METHODS: This study had institutional review board and local ethics committee approval. First, a hip phantom with steel and titanium prostheses that had inlays of water, fat, and contrast media in the pelvis was used to optimize the IFS algorithm. Second, 41 consecutive patients with hip prostheses who were undergoing CT were included. Data sets were reconstructed with filtered back projection, the IFS algorithm, and a linear interpolation MAR algorithm. Two blinded, independent readers evaluated axial, coronal, and sagittal CT reformations for overall image quality, image quality of pelvic organs, and assessment of pelvic abnormalities. CT attenuation and image noise were measured. Statistical analysis included the Friedman test, Wilcoxon signed-rank test, and Levene test. RESULTS: Ex vivo experiments demonstrated an optimized IFS algorithm by using a threshold of 2200 HU with four iterations for both steel and titanium prostheses. Measurements of CT attenuation of the inlays were significantly (P < .001) more accurate for IFS when compared with filtered back projection. In patients, best overall and pelvic organ image quality was found in all reformations with IFS (P < .001). Pelvic abnormalities in 11 of 41 patients (27%) were diagnosed with significantly (P = .002) higher confidence on the basis of IFS images. CT attenuation of bladder (P < .001) and muscle (P = .043) was significantly less variable with IFS compared with filtered back projection and linear interpolation MAR. In comparison with that of FBP and linear interpolation MAR, noise with IFS was similar close to and far from the prosthesis (P = .295). CONCLUSION: The IFS algorithm for CT image reconstruction significantly reduces metal artifacts from hip prostheses, improves the reliability of CT number measurements, and improves the confidence for depicting pelvic abnormalities.

Yield and proliferation rate of adipose-derived stromal cells as a function of age, body mass index and harvest site-increasing the yield by use of adherent and supernatant fractions?

BACKGROUND AIMS: Adipose-derived stem cells are easily accessed and have a relatively high density compared with other mesenchymal stromal cells. Isolation protocols of adipose-derived stem cells (ASC) rely on the cell's ability to adhere to tissue culture plastic overnight. It was evaluated whether the floating ASC fractions are also of interest for cell-based therapies. In addition, the impact of age, body mass index (BMI) and harvest site was assessed. METHODS: The surface protein profile with the use of flow cytometry, the cell yield and the doubling time of passages 4, 5 and 6 of ASC from 30 donors were determined. Adherent and supernatant fractions were compared. The impact of age, BMI and harvest site on cell yield and doubling times was determined. RESULTS: Both adherent and supernatant fractions showed high mean fluorescence intensities for CD13, CD29, CD44, CD73, CD90 and CD105 and comparatively low mean fluorescence intensities for CD11b, CD62L, intracellular adhesion molecule-1 and CD34. Doubling times of adherent and supernatant fractions did not differ significantly. Whereas the old age group had a significantly lower cell yield compared with the middle aged group, BMI and harvest site had no impact on cell yield. Finally, doubling times for passages 4, 5 and 6 were not influenced by the age and BMI of the donors, nor the tissue-harvesting site. CONCLUSIONS: The floating ASC fraction is an equivalent second cell source just like the adherent ASC fraction. Donor age, BMI and harvest site do not influence cell yield and proliferation rate.

The SCIentinel study--prospective multicenter study to define the spinal cord injury-induced immune depression syndrome (SCI-IDS)--study protocol and interim feasibility data.

BACKGROUND: Infections are the leading cause of death in the acute phase following spinal cord injury and qualify as independent risk factor for poor neurological outcome ("disease modifying factor"). The enhanced susceptibility for infections is not stringently explained by the increased risk of aspiration in tetraplegic patients, neurogenic bladder dysfunction, or by high-dose methylprednisolone treatment. Experimental and clinical pilot data suggest that spinal cord injury disrupts the balanced interplay between the central nervous system and the immune system. The primary hypothesis is that the Spinal Cord Injury-induced Immune Depression Syndrome (SCI-IDS) is 'neurogenic' including deactivation of adaptive and innate immunity with decreased HLA-DR expression on monocytes as a key surrogate parameter. Secondary hypotheses are that the Immune Depression Syndrome is i) injury level- and ii) severity-dependent, iii) triggers transient lymphopenia, and iv) causes qualitative functional leukocyte deficits, which may endure the post-acute phase after spinal cord injury. METHODS/DESIGN: SCIentinel is a prospective, international, multicenter study aiming to recruit about 118 patients with acute spinal cord injury or control patients with acute vertebral fracture without neurological deficits scheduled for spinal surgery. The assessment points are: i) <31 hours, ii) 31-55 hours, iii) 7 days, iv) 14 days, and v) 10 weeks post-trauma. Assessment includes infections, concomitant injury, medication and neurological classification using American Spinal Injury Association impairment scale (AIS) and neurological level. Laboratory analyses comprise haematological profiling, immunophenotyping, including HLA-DR expression on monocytes, cytokines and gene expression of immune modulators. We provide an administrative interim analysis of the recruitment schedule of the trial. DISCUSSION: The objectives are to characterize the dysfunction of the innate and adaptive immune system after spinal cord injury and to explore its proposed 'neurogenic' origin by analyzing its correlation with lesion height and severity. The trial protocol considers difficulties of enrolment in an acute setting, and loss to follow up. The administrative interim analysis confirmed the feasibility of the protocol. Better understanding of the SCI-IDS is crucial to reduce co-morbidities and thereby to attenuate the impact of disease modifying factors to protect neurological "outcome at risk". This putatively results in improved spinal cord injury medical care. TRIAL REGISTRATION DRKS-ID: DRKS00000122 (German Clinical Trials Registry).

Magnetic resonance imaging frequently changes classification of acute traumatic thoracolumbar spine injuries.

OBJECTIVE: To evaluate the influence of additional (MRI) compared with computed tomography (CT) alone for the classification of traumatic spinal injuries using the Arbeitsgemeinshaft für Osteosynthesefragen (AO) system and the Thoraco-Lumbar Injury Classification and Severity (TLICS) scale. MATERIALS AND METHODS: Images from 100 consecutive patients with at least one fracture on CT were evaluated retrospectively by three radiologists with regard to the AO and TLICS classification systems in 2 steps. First, all images from the initial CT examination were analyzed. Second, 6 weeks later, CT and MR images were analyzed together. Descriptive statistics and Wilcoxon tests were performed to identify changes in the number of fractures and ligamentous lesions detected and their corresponding classification. RESULTS: CT and MRI together revealed a total of 196 fractures (CT alone 162 fractures). The AO classification changed in 31 %, the TLICS classification changed in 33 % of the patients compared with CT alone. Based on CT and MRI together, the TLICS value changed from values <5 (indication for conservative therapy) to values ≥ 5 (indication for surgical therapy) in 24 %. CONCLUSION: MRI of patients with thoracolumbar spinal trauma considerably improved the detection of fractures and soft tissue injuries compared with CT alone and significantly changed the overall trauma classification.

Treatment modality in type II odontoid fractures defines the outcome in elderly patients.

BACKGROUND: Odontoid fractures account for approximately 20% of all fractures of the cervical spine. They represent the most common cervical spine injury for patients older than 70 years, the majority being type II fractures (65-74%), which are considered to be relatively unstable. The management of these fractures is controversial. Possible treatment options are either conservative or surgical. Surgical procedures include either anterior screw fixation of the odontoid or posterior C1/C2 fusion. The aim of this study was to compare the outcome of the three treatment modalities in elderly patients. METHODS: Between June 2004 and February 2010, all patients older than 65 years (n = 47) with type II fractures of the odontoid according to the Anderson and D'Alonso classification were retrospectively reviewed. RESULTS: In the non-operatively managed cohort, 11 patients (79%) died postoperatively within a mean period of 23 months. In all other cases (n = 3), radiographs demonstrated non-union. The mean lateral displacement was 1.9 mm (range 0-5,8 mm) and a mean angulation of 29,1° (range 0-55°) was found.Anterior screw fixation was carried out in 17 patients. The non-union rate in this cohort was 77%. In patients with a posterior C1-C2 fusion, a bony fusion of the posterior elements was found in 15 of 16 cases (93%). Survival rates were significantly higher among the group of patients who were treated with anterior screw fixation or posterior C1/C2 fusion compared to the conservatively treated group. CONCLUSION: We found the best clinical results with low rates of non-union as well as low mortality rates following posterior C1/C2 fusion making this our treatment of choice especially in an elderly patient collective.

Histological remodelling of demineralised bone matrix allograft in posterolateral fusion of the spine--an ex vivo study.

BACKGROUND: Demineralised bone matrix (DBM) has shown to be effective in enhancing posterior fusion of the spine. Several animal studies and clinical investigations in humans showed its successful remodelling. The use of allogenic matrix may decrease the need of autologous bone graft and therefore helps prevent corresponding donor site morbidity. Since DBM products are very expensive, the question arises, whether it is completely remodelled into new bone, and therefore truly is comparable to autologous cancellous bone graft. To our knowledge there is no report of a consecutive series of patients where ex vivo histological analysis after postero-lateral fusion of the spine was performed. METHODS: Osseous biopsies of nine consecutive patients who underwent postero-lateral fusion of the spine for trauma were obtained at the time of elective removal of the hardware. Histological samples were then analyzed on ground and thin sections stained with toluidine blue and von Kossa stainings. RESULTS: Time span between index operation and removal of the metal ranged between 6 and 18 month. Histological analysis showed good incorporation and overall remodelling of DBM into new bone in all patients. No foreign body reaction was visible and new bone formation progressed time dependently with DBM in situ. Four out of nine patients showed more than 50% new bone formation after one year. CONCLUSION: DBM shows good overall remodelling properties in histological analysis and therefore seems to be an effective adjunct in postero-lateral fusion of the spine. Furthermore, DBM substitution increases over time.