Spine surgery in a state-of-the-art hybrid operating room: an experience of 1745 implanted pedicle screws in the thoracolumbar spine.

Hybrid-operating rooms (hybrid-OR) combine high-resolution 2D images and 3D-scans with the possibility of 3D-navigation and allow minimal invasive pedicle screw placement even in the upper thoracic spine. The disadvantage of high cost and increased radiation needs to be compensated with high accuracy and safety. The hybrid operating room consists of a floor-based flat-panel robotic C-arm with 3D-scan capability (Artis Zeego, Siemens; Germany) combined with navigation (BrainLAB Curve, BrainLAB; Germany). Through a minimally invasive incision, a Jamshidi needle was advanced through the pedicle and a K-wire was placed. If 2D image quality did not allow safe placement 3D-navigation was used to place the K-wire. Position was controlled through a 3D-Scan and corrected if necessary before screw placement. Postoperative CTs evaluated screw perforation grade with grade I when completely within the pedicle, II < 2 mm, III 2-4 mm, and IV > 4 mm outside the pedicle. Overall, 354 screws were placed in T1-T6, 746 in the lower thoracic spine T7-T12 and 645 in the L1-L5. Navigation was mainly used in upper thoracic spine cases (31 of 57). In 63 out of 326 cases K-wire was corrected after the 3D-Scan. Overall, 99.1% of the screws showed perforation less than 2 mm. Mean radiation was 13.3 ± 11.7 mSv and significantly higher in the upper thoracic spine and in navigated procedures. Despite higher costs and radiation, the hybrid-OR allows highest accuracy and therefore patient safety in minimal invasive pedicle screw placement in the thoracic and lumbar spine.

Cement augmentation of the proximal femur nail antirotation: is it safe?

BACKGROUND: Cement augmentation of the proximal femur nail antirotation (PFNA; Fa. DePuy Synthes) showed good biomechanical and clinical results regarding increased stability and functional outcome [Linden et al. in J Orthop Res 24:2230-2237, 2006;Kammerlander et al. in Injury 49:1436-1444, 2018;]. Cement-associated complications are well known in orthopedic procedures like hip arthroplasty, vertebra- and kyphoplasty. This study investigates outcome and safety of augmentation of the proximal femur nail blade. MATERIALS AND METHODS: The retrospective review of the 299 patients (mean age 80 ± 13 years; 205 women and 94 men) focused on perioperative complications after augmentation which was performed with Traumacem V+ Cement (Fa. DePuy Synthes) in 152 cases. The decision for augmentation of the blade was made by the attending surgeon and based on the factors age, bone quality, and fracture pattern. Primary outcome measures were changes in blood pressure, heart rate or oxygen saturation, and the number of needed vasoactive drugs during augmentation. Secondary outcome measures where the rate of cement leakage into the joint, mechanical failure, and perioperative complications like pulmonary embolism, stroke, or heart attack. RESULTS: In 152 augmented cases, no leakage of cement into the joint could be detected. No signs of mechanical failure like cut-out of the blade were seen after 6 weeks and 3 months. Also, augmentation did not show a higher rate of mortality or postoperative complications like stroke, heart attack, embolism, or infection. 57 of 152 augmented cases received an intraoperative intervention with vasoactive medication at the time of augmentation either prophylactically or because of a blood pressure fall. Out of the non-augmented cases, 21 of 147 needed vasoactive medication in the second half of the operation. The difference between these groups was significant (p < 0.05). In the cases without an intervention, there was a significant blood pressure fall of about 8 ± 7.4 mmHg during the augmentation (p < 0.001). Still, none of the augmented cases showed a change in heart rate or oxygen saturation. CONCLUSION: The augmentation of the PFNA blade proved to be a safe procedure. Cement augmentation will not increase postoperative complications or mortality. The risk for leakage of cement into the joint is low and mechanical cut-out might be prevented. The decision for augmentation should be made carefully and always be declared loud and in advance to allow the anesthetist to prepare, because blood pressure changes can occur.

Impact of oral anticoagulation on proximal femur fractures treated within 24 h - A retrospective chart review.

BACKGROUND: About one third of all patients with proximal femur fractures take oral anticoagulation like aspirin (ASS), direct platelet aggregation inhibitors like Clopidogrel and Ticagrelor (PAI), vitamin-K-antagonists like Warfarin (VKA) and direct oral anticoagulants like Rivaroxaban, Dabigatran and Apixaban (DOAC). The management and timing of fracture stabilization of these patients is a rising challenge in orthopedic trauma. Our objective was to determine the effect of oral anticoagulation on patients with proximal femur fractures, which received a proximal femur nail antirotation (PFNA) within 24 h after trauma. MATERIAL AND METHODS: A retrospective chart review of 327 patients (mean age 80 ± 13 years; 223 women and 104 men) with sub- or intertrochanteric fractures between January 2013 and December 2017 was performed. All patients underwent surgery in the first 24 h after admission. Solely patients without or with only one type of oral anticoagulation were included. There were 74 patients with ASS, 30 with PAI, 52 with DOAC and 25 with VKA medication. All patients taking VKA received high dose Vitamin K or coagulation factors to normalize INR prior to surgery. Primary outcome measures were transfusion rate and pre- and postoperative hemoglobin (Hb) difference. Secondary outcome measures were mortality and complications like infection, hematoma and acute cardiovascular events. RESULTS: Patients undergoing treatment with DOAC had a 3.4-fold increased risk for intraoperative blood transfusion. The risk for blood transfusion for patients taking ASS, PAI or VKA did no differ from the control group. Patients without an intraoperative blood transfusion on oral anticoagulation showed no increase in pre- and postoperative Hb-difference compared with controls. Anticoagulation showed no significant effect on complication rates and mortality in patients operated within the first 24 h. CONCLUSION: Early surgical care of proximal femur fractures is safe even in patients with anticoagulant medication. All patients should be preoperatively prepared for possibly intraoperative transfusion, especially patients on DOAC.

Radiation exposure for the surgical team in a hybrid-operating room.

Hybrid-operating rooms enable the surgeon to acquire intraoperative high-resolution 2- and 3D images and use them for navigation. The radiation dose of the operating personal and the patient remains the major concern. In 9 months, 109 pelvic and spine cases were performed using a hybrid operating room. Radiation dose of the surgeon and the assisting nurse was recorded using real-time dosimeters. Lower radiation doses for the main surgeon in navigated dorsal instrumentations of the thoracic spine were recorded. Standing between the C-arm during screw placement increased the radiation dose sixfold. Lumbar dorsal instrumentation showed a similar radiation dose compared to the previous studies in traditional operating room settings. The use of a hybrid-operating room for dorsal spine instrumentation showed no increase in radiation dose compared to traditional settings. Intraoperative navigation can help to reduce the radiation dosage for the operating personnel.

Translocation of a gut pathobiont drives autoimmunity in mice and humans.

Despite multiple associations between the microbiota and immune diseases, their role in autoimmunity is poorly understood. We found that translocation of a gut pathobiont, Enterococcus gallinarum, to the liver and other systemic tissues triggers autoimmune responses in a genetic background predisposing to autoimmunity. Antibiotic treatment prevented mortality in this model, suppressed growth of E. gallinarum in tissues, and eliminated pathogenic autoantibodies and T cells. Hepatocyte-E. gallinarum cocultures induced autoimmune-promoting factors. Pathobiont translocation in monocolonized and autoimmune-prone mice induced autoantibodies and caused mortality, which could be prevented by an intramuscular vaccine targeting the pathobiont. E. gallinarum-specific DNA was recovered from liver biopsies of autoimmune patients, and cocultures with human hepatocytes replicated the murine findings; hence, similar processes apparently occur in susceptible humans. These discoveries show that a gut pathobiont can translocate and promote autoimmunity in genetically predisposed hosts.

Accuracy of computer-assisted iliosacral screw placement using a hybrid operating room.

INTRODUCTION: In recent years hybrid operating rooms were established all over the world. In our setting we combined a 3D flat-panel c-arm (Artis zeego, Siemens) with a navigation system (BrainLab curve, BrainLab). This worldwide unique combination enables the surgeon to visualise an entire pelvis in CT-like image quality with a single 3D-scan. The aim of our study was to investigate, if utilisation of a hybrid operating room increases the accuracy of SI-screws in comparison to standard 3D-navigation. MATERIAL AND METHODS: Retrospective, not randomised single centre case series at a level I trauma centre. Inclusion criterion was insertion of a percutaneous iliosacral screw using image-guidance in the hybrid operating room. 61 patients (35 female, 26 male) were included from June 2012 till October 2014. 65 iliosacral screws were inserted. Intraoperative 3D-scans and postoperative scans were examined to investigate screw placement. The results were compared to a preceding study performed in 2012 using conventional 3D-navigation. Statistical calculations were performed with Microsoft Excel 2011 and SPSS. RESULTS: 65 iliosacral screws were implanted. Two different types of screws were implanted: 1. "Standard" iliosacral screws stabilizing one joint/a unilateral fracture. 2. Single SI-screws stabilizing both SI-joints and if present a bilateral fracture. Forty one patients were included in group 1 (screws n=45). There was no perforation in 43 screws, grade 1 perforation in 2 screws. There was no grade 2 or 3 perforation in this group. Compared to the conventional 3D-navigated screws there was a highly significant difference (p<0.001). Twenty patients could be included in group 2. Eleven screws showed a complete intraosseous position. There was grade 1 perforation in 2 screws, grade 2 perforation in 5 screws and grade 3 perforation in 2 screws. CONCLUSION: Improvements in image quality and enlargement of the display window lead to better intraoperative visualisation of the entire dorsal pelvis. Thereby the accuracy of computer-assisted iliosacral screws could be increased using a hybrid operating room. Furthermore difficult tasks like a single screw for both joints can be accomplished.

[Image-based guidance in shoulder traumatology. Initial clinical experience]. / System zur bildbasierten Zielführung in der Schultertraumatologie. Erste klinische Erfahrungen.

Computer-assisted systems are used frequently in pelvis and spine surgery but are still rare in general trauma and hardly ever used in shoulder surgery. The major limitation is the use of rigid markers and the problem of obtaining navigable images in the complex shoulder region. The aim of this study was to evaluate the use of a new image-based guidance system in shoulder traumatology. The system was used to implant a tightrope system in Tossy III lesions of the AC joint (n=7) and compared to the conventional method (n=8). Outcome parameters were duration of surgery, number of trials for perfect positioning of the guide wire, C-arm shots used till K-wire position is accepted, duration of radiation and surgeon's comment on usability and benefit. The new system did not shorten the surgical procedure significantly (45 vs 49 min, p=0.6) but reduced the average overall radiation time from 152 to 90 s (p=0.3). The number of shots to implant the guide-wire could be reduced significantly from 8 to 5 (p=0.01). The number of trials to implant the guide wire was less in the image-guided group compared to the conventional group (1 vs 2, p=0.02). For the first time image-based guidance was used in shoulder traumatology. The system holds high potential to assist surgeons without disturbing the workflow in assuring guide wire positioning, reduce the number of dangerous mistrials and reduce the emission of radiation.

Safety and preliminary efficacy of plerixafor (Mozobil) in combination with chemotherapy and G-CSF: an open-label, multicenter, exploratory trial in patients with multiple myeloma and non-Hodgkin's lymphoma undergoing stem cell mobilization.

Plerixafor, a novel CXCR4 inhibitor, is effective in mobilizing PBSCs particularly when used in conjunction with G-CSF. In four cohorts, this pilot study explored the safety of plerixafor mobilization when incorporated into a conventional stem cell mobilization regimen of chemotherapy and G-CSF. Forty (26 multiple myeloma and 14 non-Hodgkin's lymphoma) patients were treated with plerixafor. Plerixafor was well tolerated and its addition to a chemo-mobilization regimen resulted in an increase in the peripheral blood CD34+ cells. The mean rate of increase in the peripheral blood CD34+ cells was 2.8 cells/microl/h pre- and 13.3 cells/microl/h post-plerixafor administration. Engraftment parameters were acceptable after myeloblative chemotherapy, with the median day for neutrophil and plt engraftment being day 11 (range 8-20 days) and day 13 (range 7-77 days), respectively. The data obtained from the analysis of the cohorts suggest that plerixafor can safely be added to chemotherapy-based mobilization regimens and may accelerate the rate of increase in CD34+ cells on the second day of apheresis. Further studies are warranted to evaluate the effect of plerixafor in combination with chemomobilization on stem cell mobilization and collection on the first and subsequent days of apheresis, and its impact on resource utilization.

Intramuscular pressure, tissue oxygenation and EMG fatigue measured during isometric fatigue-inducing contraction of the multifidus muscle.

Simultaneous measurement of intramuscular pressure (IMP), tissue oxygen partial pressure (pO(2)) and EMG fatigue parameters in the multifidus muscle during a fatigue-inducing sustained muscular contraction. The study investigated the following hypotheses: (1) Increases in IMP result in tissue hypoxia; (2) Tissue hypoxia is responsible for loss of function in the musculature. The nutrient supply to muscle during muscle contraction is still not fully understood. It is assumed that muscle contraction causes increased tissue pressure resulting in compromised perfusion and tissue hypoxia. This tissue hypoxia, in turn, leads to muscle fatigue and therefore to loss of function. To the authors' knowledge, no study has addressed IMP, pO(2) and EMG fatigue parameters in the same muscle to gain a deeper sight into muscle perfusion during contraction. As back muscles need to have a constant muscular tension to maintain trunk stability during stance and locomotion, muscle fatigue due to prolonged contraction-induced hypoxia could be an explanation for low back pain. Sixteen healthy subjects performed an isometric muscular contraction exercise at 60% of maximum force until the point of localized muscular fatigue. During this exercise, the individual changes of IMP, pO(2) and the median frequency (MF) of the surface EMG signal of the multifidus muscle were recorded simultaneously. In 12 subjects with a documented increase in intramuscular pressure, only five showed a decrease in tissue oxygen partial pressure, while this parameter remained unchanged in six other subjects and even increased in one. A fall in tissue pO(2) was associated with a drop in MF in only five subjects, while there was no correlation between these parameters in the other 11 subjects. To summarize, an increase in IMP correlated with a decrease in pO(2) and a drop in MF in only five out of 16 subjects. High intramuscular pressure values are not always associated with a hypoxia in muscle tissue. Tissue hypoxia is not automatically associated with a median frequency shift in the EMG signal's power spectrum.