A Novel Four-Gene Prognostic Signature for Prediction of Survival in Patients with Soft Tissue Sarcoma

Soft tissue sarcomas (STS), a group of rare malignant tumours with high tissue heterogeneity, still lack effective clinical stratification and prognostic models. Therefore, we conducted this study to establish a reliable prognostic gene signature. Using 189 STS patients’ data from The Cancer Genome Atlas database, a four-gene signature including DHRS3, JRK, TARDBP and TTC3 was established. A risk score based on this gene signature was able to divide STS patients into a low-risk and a high-risk group. The latter had significantly worse overall survival (OS) and relapse free survival (RFS), and Cox regression analyses showed that the risk score is an independent prognostic factor. Nomograms containing the four-gene signature have also been established and have been verified through calibration curves. In addition, the predictive ability of this four-gene signature for STS metastasis free survival was verified in an independent cohort (309 STS patients from the Gene Expression Omnibus database). Finally, Gene Set Enrichment Analysis indicated that the four-gene signature may be related to some pathways associated with tumorigenesis, growth, and metastasis. In conclusion, our study establishes a novel four-gene signature and clinically feasible nomograms to predict the OS and RFS. This can help personalized treatment decisions, long-term patient management, and possible future development of targeted therapy

Percutaneous iliosacral screw fixation in S1 and S2 for posterior pelvic ring injuries: technique and perioperative complications

Objective: Percutaneous iliosacral screw placement allows for minimally invasive fixation of posterior pelvic ring instabilities. The objective of this study was to describe the technique for screws in S1 and S2 using conventional C-arm and to evaluate perioperative complications. Methods: Thirty-eight consecutive patients after percutaneous pelvic ring fixation with cannulated screws in S1 and S2 using conventional C-arm fluoroscopy were analysed. Accuracy of screw placement, nerval lesions, need for second surgery, operation time, and time to full weight bearing were assessed postoperatively and during regular follow-up examinations. Results: Twenty-one patients underwent unilateral screw fixation and 17 patients underwent bilateral screw fixation. In total, 83 screws were placed. Mean age of the patients was 52±19years. Mean operation time was 16±7min/screw. Mean follow-up was 5±3months. Time to full weight bearing in 28 patients was 9±4weeks. Eight patients were still not able to support full weight bearing, partially due to concomitant injuries. Patients without concomitant injuries that affected walking were able to bear full weight after 8±4weeks (n=17). Two patients had persistent postoperative hypaesthesia. No motor weakness was apparent and no postoperative bleeding was observed. Secondary surgery due to screw malpositioning or loosening had to be performed in four patients. The presence of a screw in S2 was not indicated for perioperative complications. Conclusions: Percutaneous iliosacral screw fixation is a rapid and definitive treatment for posterior pelvic ring injuries with a low risk of secondary bleeding during posterior pelvic stabilization. The technique using standard C-arm fluoroscopy was also found to be safe for screws placed in S

Assessment of Non-Invasive Blood Pressure Prediction from PPG and rPPG Signals Using Deep Learning

Exploiting photoplethysmography signals (PPG) for non-invasive blood pressure (BP) measurement is interesting for various reasons. First, PPG can easily be measured using fingerclip sensors. Second, camera based approaches allow to derive remote PPG (rPPG) signals similar to PPG and therefore provide the opportunity for non-invasive measurements of BP. Various methods relying on machine learning techniques have recently been published. Performances are often reported as the mean average error (MAE) on the data which is problematic. This work aims to analyze the PPG- and rPPG based BP prediction error with respect to the underlying data distribution. First, we train established neural network (NN) architectures and derive an appropriate parameterization of input segments drawn from continuous PPG signals. Second, we use this parameterization to train NNs with a larger PPG dataset and carry out a systematic evaluation of the predicted blood pressure. The analysis revealed a strong systematic increase of the prediction error towards less frequent BP values across NN architectures. Moreover, we tested different train/test set split configurations which underpin the importance of a careful subject-aware dataset assignment to prevent overly optimistic results. Third, we use transfer learning to train the NNs for rPPG based BP prediction. The resulting performances are similar to the PPG-only case. Finally, we apply different personalization techniques and retrain our NNs with subject-specific data for both the PPG-only and rPPG case. Whilst the particular technique is less important, personalization reduces the prediction errors significantly

Stand-alone percutaneous stent-kyphoplasty for thoracolumbar split and burst-split fractures

Introduction Traditionally, thoracolumbar split and burst-split fractures are treated with combined antero-posterior bi-segmental fusion procedures. Especially in the lower lumbar spine, such interventions are invasive and are associated with increased risk of neurological and vascular complications. This retrospective study aims to determine whether percutaneous stent-kyphoplasty is a viable treatment option for these injuries in terms of kyphotic angle correction and patient safety. Methods From Nov. 2014 to Dec. 2017, 25 consecutive patients (9 female, mean age 58 years) with 8 thoracolumbar split and 17 burst-split fractures (T11 to L5) of different etiology (7 high vs. 18 low energy trauma) were treated with percutaneous stent-kyphoplasty (SpineJack®). CT and/or MR imaging was performed preoperatively in all patients while radiographs were obtained postoperatively and at each follow-up. The mean follow-up was 176 days (SD 130). All cases were evaluated retrospectively for complications regarding nervous damage, LOS, duration of opioid intake, pain-VAS, return to work time and change of radiographic kyphotic angle. Results The mean kyphotic angle did not change from 1.1° (SD 9.2°) preoperatively to 1.1° (SD 7.9°) postoperatively. Radiologically, the mean increase of the kyphotic angle between surgery and the last follow-up was 2.65° (SD 4.2°). The mean pain-VAS was reduced to 1.8 postoperatively (SD 2.5, p = 0.03). The mean opioid intake duration was 4 days. Conclusion SpineJack®-kyphoplasty appears to be a safe and expeditious, minimally invasive treatment option for thoracolumbar split or burst-split fractures. It may be considered as an alternative to combined anterior-posterior instrumented bi-segmental fusion with its associated surgical morbidity

Influence of trabecular microstructure and cortical index on the complexity of proximal humeral fractures

Objectives: Poor bone quality increases the susceptibility to fractures of the proximal humerus. It is unclear whether local trabecular and cortical measures influence the severity of fracture patterns. The goal of this study was to assess parameters of trabecular and cortical bone properties and to compare these parameters with the severity of fractures and biomechanical testing. Methods: Twenty patients with displaced proximal humeral fractures planned for osteosynthesis were included. Fractures were classified as either 2-part fractures or complex fractures. Bone after core drilling was harvested during surgery from the humeral head in each patient. Twenty bone cores obtained from nonpaired cadaver humeral heads served as nonfractured controls. Micro-CT (μCT) was performed and bone volume/total volume (BV/TV), connectivity density (CD), trabecular number (Tb.N), trabecular thickness (Tb.Th), trabecular spacing (Tb.Sp), and bone mineral density (BMD) were assessed. The cortical index (CI) was determined from AP plain films. Biomechanical testing was done after μCT scanning by axially loading until failure, and ultimate strength and E modulus were recorded. Results: BV/TV, BMD and CD showed moderate to strong correlations with biomechanical testing (r=0.45-0.76, all p<0.05). No significant differences were detected between the 2-part and complex fracture groups and controls regarding μCT and biomechanical parameters. CI was not significantly different between the 2-part and complex fracture groups. Conclusions: In our study population local trabecular bone structure and cortical index could not predict the severity of proximal humeral fractures in the elderly. Complex fractures do not necessarily imply lower bone quality compared to simple fracture

Quality of reduction correlates with clinical outcome in pelvic ring fractures

INTRODUCTION Posttraumatic pelvic deformity is associated with pain and loss of function. This study aimed to test the correlation of functional outcome in patients with pelvic fractures with the postoperative radiographic quality of reduction. METHODS Consecutive patients with an isolated traumatic pelvic fracture that required closed or open reduction between 07/2015 and 07/2017 and had a completed follow-up of at least 6 months were included (N = 31, mean age 50 years, SD 21 years, range, 16 to 88 years). Majeed and Timed Up & Go were obtained from a prospective outcome database at 6 months and last follow-up (mean 10 months, SD 5 months). Quality of pelvic ring reduction was determined on postoperative radiographs as described by Matta, Sagi and Keshishyan/Lefaivre. RESULTS Clinical outcome at 6 months as measured by the Majeed and the Timed Up & Go correlated moderately with Keshishyan/Lefaivre's pelvic asymmetry value (Pearson R: -0.520 and 0.585, p ≤ 0.003) and the pelvic deformity index (-0.527 and 0.503, p ≤ 0.004). There was a weak correlation between the Timed Up & Go and the radiographic grading system as described by Matta/Tournetta at 6 months (0.408, p = 0.023) and at last follow-up (0.380, p = 0.035). CONCLUSIONS This study showed a moderate correlation of the clinical outcome at 6 months with postoperative quality of radiographic reduction when measured with the method described by Keshishyan and Lefaivre. Although having only descriptive value due to the small cohort, our findings underline the importance of anatomic reduction and restoration of pelvic symmetry in patients with pelvic trauma. Future studies with more patients and more investigators are required and reliability and validity of functional outcome scores needs to be further assessed to predict outcome in patient with fractures of the pelvic ring. LEVEL OF EVIDENCE Level IV (case series)

The calcar screw in angular stable plate fixation of proximal humeral fractures - a case study

<p>Abstract</p> <p>Background</p> <p>With new minimally-invasive approaches for angular stable plate fixation of proximal humeral fractures, the need for the placement of oblique inferomedial screws ('calcar screw') has increasingly been discussed. The purpose of this study was to investigate the influence of calcar screws on secondary loss of reduction and on the occurrence of complications.</p> <p>Methods</p> <p>Patients with a proximal humeral fracture who underwent angular stable plate fixation between 01/2007 and 07/2009 were included. On AP views of the shoulder, the difference in height between humeral head and the proximal end of the plate were determined postoperatively and at follow-up. Additionally, the occurrence of complications was documented. Patients with calcar screws were assigned to group C+, patients without to group C-.</p> <p>Results</p> <p>Follow-up was possible in 60 patients (C+ 6.7 ± 5.6 M/C- 5.0 ± 2.8 M). Humeral head necrosis occurred in 6 (C+, 15.4%) and 3 (C-, 14.3%) cases. Cut-out of the proximal screws was observed in 3 (C+, 7.7%) and 1 (C-, 4.8%) cases. In each group, 1 patient showed delayed union. Implant failure or lesions of the axillary nerve were not observed. In 44 patients, true AP and Neer views were available to measure the head-plate distance. There was a significant loss of reduction in group C- (2.56 ± 2.65 mm) compared to C+ (0.77 ± 1.44 mm; p = 0.01).</p> <p>Conclusions</p> <p>The placement of calcar screws in the angular stable plate fixation of proximal humeral fractures is associated with less secondary loss of reduction by providing inferomedial support. An increased risk for complications could not be shown.</p

Does the accuracy of prehospital pelvic binder placement affect cardiovascular physiological parameters during rescue? A clinical study in patients with pelvic ring injuries

Introduction: Pelvic binders (PB) have become an established first-line treatment for on scene use in suspected pelvic ring injuries. A sustained incidence of incorrect placements was reported, usually above the trochanteric region. We examined if malplacement is associated with worse clinical parameters related to resuscitation. Methods: Retrospective chart review, level 1 center over a 3-year period. Inclusion criteria: adult patients (18-69y/o), high-energy injury, presence of a pelvic binder on admission - patients without binders served as controls. Exclusions: geriatric patients (>70y/o), ground level falls. Malplacement of the binder was assessed and graded (grade 1: 10 cm) from the initial computed tomography scan (3D reconstruction). Results: Seventy-six patients were included. Males (72%), mean age 47years (range 18-91, SD 19.4). Mean Injury Severity Score was 22.3 points (range 1 -48, SD 10.4) and mean Glasgow Coma Score on arrival was 10.8 points (range 3-15, SD 5.3). Fifty-three percent presented with a pelvic ring injury (74% of them with a type B or C fracture). Mean PB distance from the trochanteric region was 56 mm (range 41-247 mm, SD 54.5). Fifty percent of PBs were moderately displaced, 21% showed severe misplacement (>100 mm). Physiological parameters were unchanged regardless of the accuracy of PB placement. Conclusion: Incorrect placement of pelvic binders persists despite widespread implementation of the device. In our series, displacement was always cranially and had no effect on preclinical fluids received or parameters of resuscitation on arrival

The fascial connections of the pectineal ligament

In clinical settings, the pectineal ligament forms a basic landmark for surgical approaches. However, to date, the detailed fascial topography of this ligament is not well understood. The aim of this study was to describe the morphology of the pectineal ligament including its fascial connections to surrounding structures. The spatial–topographical relations of 10 fresh and embalmed specimens were dissected, stained, slice plastinated, and analyzed macroscopically, and in three cases histological approaches were also used. The pectineal ligament is attached ventrally and superiorly to the pectineus muscle, connected to the inguinal ligament by the lacunar ligament and to the tendinous origin of rectus abdominis muscle and the iliopubic tract. It forms a site of origin for the internal obturator muscle, and throughout its curved course, the ligament attaches to both the fasciae of iliopsoas and the internal obturator muscle. However, dorsally, these fasciae pass free from the bone, while the pectineal ligament itself is adhered to it. The organ fasciae are seen apart from the pectineal ligament and its connections. The pectineal ligament seems to form a connective tissue junction between the anterior and medial compartment of the thigh. This ligament, however, is free to other compartments arisen from the embryonal gut and to the urogenital ridge. These features of the pectineal ligament are important to consider during orthopedic and trauma surgical approaches, in gynecology, hernia and incontinence surgery, and in operations for pelvic floor and neovaginal reconstruction

Comparison of different CT metal artifact reduction strategies for standard titanium and carbon-fiber reinforced polymer implants in sheep cadavers

BACKGROUND CT artifacts induced by orthopedic implants can limit image quality and diagnostic yield. As a number of different strategies to reduce artifact extent exist, the aim of this study was to systematically compare ex vivo the impact of different CT metal artifact reduction (MAR) strategies on spine implants made of either standard titanium or carbon-fiber-reinforced-polyetheretherketone (CFR-PEEK). METHODS Spine surgeons fluoroscopically-guided prepared six sheep spine cadavers with pedicle screws and rods of either titanium or CFR-PEEK. Samples were subjected to single- and dual-energy (DE) CT-imaging. Different tube voltages (80, DE mixed, 120 and tin-filtered 150 kVp) at comparable radiation dose and iterative reconstruction versus monoenergetic extrapolation (ME) techniques were compared. Also, the influence of image reconstruction kernels (soft vs. bone tissue) was investigated. Qualitative (Likert scores) and quantitative parameters (attenuation changes induced by implant artifact, implant diameter and image noise) were evaluated by two independent radiologists. Artifact degree of different MAR-strategies and implant materials were compared by multiple ANOVA analysis. RESULTS CFR-PEEK implants induced markedly less artifacts than standard titanium implants (p < .001). This effect was substantially larger than any other tested MAR technique. Reconstruction algorithms had small impact in CFR-PEEK implants and differed significantly in MAR efficiency (p < .001) with best MAR performance for DECT ME 130 keV (bone kernel). Significant differences in image noise between reconstruction kernels were seen (p < .001) with minor impact on artifact degree. CONCLUSIONS CFR-PEEK spine implants induce significantly less artifacts than standard titanium compositions with higher MAR efficiency than any alternate scanning or image reconstruction strategy. DECT ME 130 keV image reconstructions showed least metal artifacts. Reconstruction kernels primarily modulate image noise with minor impact on artifact degree