Full-endoscopic uniportal retropharyngeal odontoidectomy for anterior craniocervical infection.

BACKGROUND: Infections of the anterior craniocervical junction may require surgery. There are various techniques with individual advantages and disadvantages. This study evaluates the full-endoscopic uniportal technique via the anterior retropharyngeal approach for odontoidectomy, decompression, and debridement. MATERIAL AND METHODS: Three patients with an infection of the anterior craniocervical junction with retrodental involvement were operated on between 2014 and 2016 using the full-endoscopic uniportal technique. Posterior stabilization was also performed with the same procedure for all patients. RESULTS: The operation was technically satisfactory in all cases. No problems due to swelling of the pharyngeal soft tissue occurred. No other complications were observed. All patients had a satisfactory outcome with stable regression of the myelopathy symptoms and/or complete healing of the infection. The follow-up images showed sufficient decompression of bone and soft tissues in all cases. CONCLUSIONS: The full-endoscopic uniportal technique with an anterior retropharyngeal approach can be an adequate and minimally invasive surgical technique for odontoidectomy, decompression, and debridement in infections of the craniocervical junction and can reduce access-related problems. The transoral, transnasal, and retropharyngeal approaches have different surgical fields due to the access trajectories, which must be taken into consideration depending on the anatomy and pathology when selecting a suitable technique.

Decompression of the anterior thoracic spinal canal using a novel full-endoscopic uniportal transthoracic retropleural technique-an anatomical feasibility study in human cadavers.

Surgery for thoracic disc herniation and spinal stenosis is comparatively rare and often demanding. The goal is to achieve sufficient decompression without manipulating the spinal cord. Individual planning and various surgical techniques and approaches are required. This anatomical study examines the feasibility of a novel full-endoscopic uniportal technique with a transthoracic retropleural approach for decompression of the anterior thoracic spinal canal. Operations were performed on three fresh adult cadavers. The endoscope used, from RIWOspine, Germany, has a shaft cross-section of 6.9 × 5.9 mm and a 25° view angle. It contains an eccentric intraendoscopic working channel with a diameter of 4.1 mm. A transthoracic retropleural approach was used. The anatomical structures were dissected and the anterior thoracic epidural space was decompressed. The planned steps of the operation were performed on all cadavers. The transthoracic retropleural approach allowed the target region to be accessed easily. The anatomical structures could be identified and dissected. The anterior thoracic epidural space could be decompressed sufficiently. Using the uniportal full-endoscopic operation technique with a transthoracic retropleural approach, the anterior thoracic epidural space can be adequately reached. This is a minimally invasive method with the known advantages of an endoscopic technique under continuous irrigation. The retropleural approach allows direct access. The instruments are available for clinical use and have been established for years in other operations on the entire spine. Clin. Anat. 31:716-723, 2018. © 2018 Wiley Periodicals, Inc.

SketchBio: a scientist's 3D interface for molecular modeling and animation.

BACKGROUND: Because of the difficulties involved in learning and using 3D modeling and rendering software, many scientists hire programmers or animators to create models and animations. This both slows the discovery process and provides opportunities for miscommunication. Working with multiple collaborators, a tool was developed (based on a set of design goals) to enable them to directly construct models and animations. RESULTS: SketchBio is presented, a tool that incorporates state-of-the-art bimanual interaction and drop shadows to enable rapid construction of molecular structures and animations. It includes three novel features: crystal-by-example, pose-mode physics, and spring-based layout that accelerate operations common in the formation of molecular models. Design decisions and their consequences are presented, including cases where iterative design was required to produce effective approaches. CONCLUSIONS: The design decisions, novel features, and inclusion of state-of-the-art techniques enabled SketchBio to meet all of its design goals. These features and decisions can be incorporated into existing and new tools to improve their effectiveness.

Operation of lumbar zygoapophyseal joint cysts using a full-endoscopic interlaminar and transforaminal approach: prospective 2-year results of 74 patients.

In appropriate situations, extensive decompression with laminectomy often continues to be described as the method of choice for operations involving lumbar zygoapophyseal joint (z-joint) cysts. Tissue-sparing procedures are nevertheless becoming more common. Endoscopic techniques have become the standard procedures in many areas because of the advantages they offer in terms of surgical technique and in rehabilitation. One key aspect in spinal surgery was the development of instruments for sufficient bone resection carried out under continuous visual control. This enabled endoscopes to be used when operating on z-joint cysts. The objective of this prospective study was to examine the technical possibilities for the full-endoscopic interlaminar and transforaminal technique in lumbar z-joint cysts. A total of 74 patients were followed up for 2 years. The results show that 85% of the patients no longer have any leg pain or that the pain had been almost completely eliminated, and 11 % experience occasional pain. The complication rate was low. The full-endoscopic techniques brought advantages in the following areas: operation, complications, traumatization, and rehabilitation. The recorded results show that full-endoscopic resection of a z-joint cyst using an interlaminar and transforaminal approach provides an adequate and safe supplement, and is an alternative to conventional procedures when the indication criteria are fulfilled. It also offers the advantages of a minimally invasive intervention.

Non-invasive estimation of left ventricular systolic peak pressure: a prerequisite to calculate myocardial work in hypertrophic obstructive cardiomyopathy.

AIMS: Myocardial work (MyW) is an echocardiographically derived parameter to estimate myocardial performance. The calculation of MyW utilizes pressure strain loops from global longitudinal strain and brachial blood pressure (BP) as a surrogate of left ventricular systolic pressure (LVSP). Since LVSP cannot be equated with BP in hypertrophic obstructive cardiomyopathy (HOCM), we explored whether LVSP can be derived non-invasively by combining Doppler gradients and BP. METHODS AND RESULTS: We studied 20 consecutive patients (8 women, 12 men; mean age 57.0 ± 13.9 years; NYHA 2.1 ± 0.8; maximal septal thickness 24.7 ± 6.3 mm) with indication for first alcohol septal ablation. All measurements were performed simultaneously in the catheterization laboratory (CathLab)-invasively: ascending aortic and LV pressures; non-invasively: BP, maximal (CWmax) and mean (CWmean) Doppler gradients.LVSP was 188.9 ± 38.5 mmHg. Mean gradients of both methods were comparable (CathLab 34.3 ± 13.4 mmHg vs. CW 31.0 ± 13.7 mmHg). Maximal gradient was higher in echocardiography (64.5 ± 28.8 mmHg) compared with CathLab (54.8 ± 24.0 mmHg; P < 0.05). Adding BP (143.1 ± 20.6 mmHg) to CWmax resulted in higher (207.7 ± 38.0 mmHg; P < 0.001), whereas adding BP to CWmean in lower (174.1 ± 26.1 mmHg; P < 0.01) derived LVSP compared with measured LVSP. However, adding BP to averaged CWmax and CWmean resulted in comparable results for measured and derived LVSP (190.9 ± 31.6 mmHg) yielding a favourable correlation (r = 0.87, P < 0.001) and a good level of agreement in the Bland-Altman plot. CONCLUSION: Non-invasive estimation of LVSP in HOCM is feasible by combining conventional BP and averaged CWmean and CWmax gradients. Hereby, a more reliable estimation of MyW in HOCM may be feasible.

Multicenter evaluation of therapeutic strategies of inpatients with osteoporotic vertebral fractures in Germany.

PURPOSE: The aim of this study was to assess therapeutic strategies of inpatients with osteoporotic thoracolumbar fractures (OTF) in Germany. METHODS: Prospective multi-center study including 16 German-speaking trauma centers over a period of 7 months. All inpatients with OTF were included. Radiological and clinical data on admission and treatment modalities were assessed. RESULTS: Seven hundred and seven (99.3%) out of 712 included patients (73.3% female) could be evaluated. Mean age was 75 years (30-103). 51.3% could not remember any traumatic incident. Fracture distribution was from T2 to L5 with L1 (19%) most commonly affected. According to the Magerl classification type A1 (52.1%) and A3 (42.7%) were most common. B and C type injuries (2.6%) and neurological deficits (3.1%) were rare. Previous progression of vertebral deformation was evident in 34.4% of patients and related to t score below - 3 (Odds ratio 1.9661). Patients presented with anticoagulation medication (15.4%), dementia (13%), and ASA score > 3 (12.4%) frequently. 82.3% of patients complained of pain > 4 on VAS, 37% could not be mobilized despite pain medication according to grade II WHO pain ladder. 81.6% received operative treatment. Kyphoplasty (63.8%) and hybrid stabilization including kyphoplasty with (14.4%) or without screw augmentation (7.6%) were the techniques most frequently used. Invasiveness of treatment increased with degree of instability. CONCLUSIONS: OTF are mostly type A compression fractures. Patients suffer from severe pain and immobilization frequently. Progression of deformity is correlated to t score below - 3. Treatment of inpatients is mainly surgical, with kyphoplasty followed by hybrid stabilization as commonly used techniques.

Bilateral operation of lumbar degenerative central spinal stenosis in full-endoscopic interlaminar technique with unilateral approach: prospective 2-year results of 74 patients.

STUDY DESIGN: Prospective study of the patients with degenerative spinal central stenosis, operated bilateral in a full-endoscopic unilateral technique. OBJECTIVE: The objective of this prospective study was to examine the technical possibilities of full-endoscopic interlaminar bilateral technique with unilateral approach in degenerative lumbar central spinal stenosis and predominant leg symptoms using new designed endoscopes and instruments. SUMMARY OF BACKGROUND DATA: Extensive decompression with laminectomy where appropriate, is often still described as the method of choice in the operation of degenerative lumbar spinal stenosis. Nonetheless, tissue-sparing procedures are becoming more common. Endoscopic techniques have become the standard in many areas because of the advantages they offer in surgical technique and in rehabilitation. At the spine, 1 essential point was the developing of the instruments for sufficient bone resection under continuous visual control. This enabled the use in the operation of spinal canal stenoses. METHODS: A total of 72 patients with lumbar central spinal stenosis full-endoscopic unilateral decompression were followed for 2 years. In addition to general and specific parameters, these measuring instruments were used: VAS, German version North American Spine Society Instrument, Oswestry Low-back Pain Disability Questionnaire. RESULTS: The results show that 70.8% no longer have leg pain or it was nearly completely reduced and 22.2% have occasional pain. The decompression results were equal to those of conventional procedures. The complication rate was low. The full-endoscopic techniques brought advantages in these areas: operation, complications, traumatization, and rehabilitation. CONCLUSIONS: The recorded results show that the full-endoscopic interlaminar bilateral decompression with unilateral approach is a sufficient and safe supplement and alternative to conventional procedures when the indication criteria are fulfilled. At the same time, it offers the advantages of a minimally invasive intervention.

Operation of Soft or Calcified Thoracic Disc Herniations in the Full-Endoscopic Uniportal Extraforaminal Technique.

BACKGROUND: Surgery for thoracic disc herniation and stenosis is comparatively rare and often demanding. The goal is to achieve sufficient decompression without manipulating the spinal cord and to minimize surgical trauma and its consequences. Individual planning and various surgical techniques and approaches are required. The key factors for selecting the technique are anatomical location, consistency of the pathology, general condition of the patient, and the surgeon's experience. OBJECTIVES: The objective of the study was the evaluation of the technical implementation and outcomes of a full-endoscopic uniportal technique via the extraforaminal approach in patients with symptomatic soft or calcified disc herniation of the thoracic spine, taking specific advantages and disadvantages and literature into consideration. STUDY DESIGN: Retrospective study. SETTING: A center for spine surgery and pain medicine. METHODS: Between 2009 and 2015, decompression was performed on 26 patients with thoracic disc herniation or stenosis with radicular or myelopathic symptoms in a full-endoscopic uniportal technique with an extraforaminal approach. No patients underwent additional posterior stabilization. Imaging and clinical data were collected in follow-up examinations for 18 months. RESULTS: Sufficient decompression was achieved in the full-endoscopic uniportal technique in all cases. The individual selection of the respective approach made it possible to reach the target area without manipulating the spinal cord. One patient experienced deterioration of a myelopathy. No other serious complications were observed. All patients, except one, experienced regression or improvement of symptoms. No evidence of increasing instability was found in imaging. LIMITATIONS: This is a retrospective study. The limited number of cases must be considered. CONCLUSIONS: The full-endoscopic uniportal technique with an extraforaminal approach was found to be a sufficient and minimally invasive method with the known advantages of an endoscopic procedure under continuous irrigation for monosegmental disc herniations. The inclusion criteria must be taken into consideration. If they are not met, an alternative full-endoscopic approach (interlaminar, transthoracic retropleural) or decompression in a conventional method must be selected. Additional stabilization does not appear to be necessary due to the low level of trauma. KEY WORDS: Extraforaminal approach, thoracic disc herniation, giant disc herniation, Full-endoscopic, minimally invasive, thoracic spine.

Surgical treatment of cervical subaxial intraspinal extradural cysts using a full-endoscopic uniportal posterior approach.

PURPOSE: Symptomatic intraspinal extradural cysts of the cervical subaxial spine are rare, but usually require surgery. Conventional posterior decompression is the gold standard. However, there is increasing experience with endoscopic surgical techniques. The purpose of the study is to evaluate the technical implementation and outcomes of a full-endoscopic uniportal technique via the posterior approach in patients with symptomatic intraspinal extradural cysts of the cervical subaxial spine. METHODS: Seven consecutive patients with a subaxial location of symptomatic intraspinal extradural cysts were decompressed in a full-endoscopic uniportal technique via the posterior approach between 2009 and 2015. Imaging and clinical data were collected in follow-up examinations for 18 months. RESULTS: In all cases, the cyst was completely removed and adequate decompression was achieved using the full-endoscopic uniportal technique. One patient developed a dural leak that was sutured and covered intraoperatively. No other complications requiring treatment were observed. All patients had a good clinical outcome with stable regression of the radicular and central nerve pain or neurological deficits. The imaging follow-up showed sufficient decompression in all cases. No evidence was found of increasing instability during the follow-up period. CONCLUSION: The full-endoscopic uniportal operation with a posterior approach allows the resection of the cyst and can minimize trauma and destabilization and has technical benefits and a low complication rate. It is an alternative surgical method that can offer advantages and is considered by the authors to be the surgical technique of choice for cervical subaxial intraspinal extradural cysts.

The full-endoscopic uniportal technique for decompression of the anterior craniocervical junction using the retropharyngeal approach: an anatomical feasibility study in human cadavers and review of the literature.

Objective: Acute or progressive myelopathy may necessitate direct anterior decompression of the craniocervical junction and odontoidectomy. Different techniques with individual advantages and disadvantages can be used. In addition to the gold standard-the transoral approach-there is also increasing experience with the endoscopic transnasal technique. Other alternative methods are also being developed to reduce technical and perioperative problems. The aim of this anatomical study was to investigate the feasibility of the full-endoscopic uniportal technique with a retropharyngeal approach for decompression of the craniocervical junction, taking into consideration the specific advantages and disadvantages compared with conventional methods and the currently available data in the literature. Methods: Five fresh adult cadavers were operated on. The endoscope used has a shaft cross-section of 6.9 × 5.9 mm and a 25° viewing angle. It contains an eccentric intraendoscopic working channel with a diameter of 4.1 mm. An anterior retropharyngeal approach was used. The anatomical structures of the anterior craniocervical junction were dissected and the bulbomedullary junction was decompressed. Results: The planned steps of the operation were performed in all cadavers. The retropharyngeal approach allowed the target region to be accessed easily. The anatomical structures of the anterior craniocervical junction could be identified and dissected. The bulbomedullary junction could be adequately decompressed. No resections of the anterior arch of the atlas were necessary in the odontoidectomy. Conclusions: Using the full-endoscopic uniportal technique with an anterior retropharyngeal approach, the craniocervical region can be adequately reached, dissected, and decompressed. This is a minimally invasive technique with the known advantages of an endoscopic procedure under continuous irrigation. The retropharyngeal approach allows direct, sterile access. The instruments are available for clinical use and have been established for years in other operations of the entire spine.

Full-endoscopic Uniportal Odontoidectomy and Decompression of the Anterior Cervicomedullary Junction Using the Retropharyngeal Approach.

STUDY DESIGN: A study of a series of consecutive full-endoscopic uniportal decompressions of the anterior craniocervical junction with retropharyngeal approach. OBJECTIVE: The aim of this study was to evaluate the direct anterior decompression of the craniocervical junction in patients with bulbomedullary compression using a full-endoscopic uniportal technique via an anterolateral retropharyngeal approach. SUMMARY OF BACKGROUND DATA: Acute or progressive myelopathy may necessitate direct anterior decompression of the craniocervical junction and odontoidectomy. Different techniques with individual advantages and disadvantages can be used. In addition to the gold standard - the transoral approach - there is increasing experience with the endoscopic transnasal technique. Other alternative procedures are also being developed. METHODS: Between 2013 and 2016, eight patients with basilar impression, retrodental pannus, or retrodental infection were operated in the full-endoscopic uniportal technique with a retropharyngeal approach. Anterior decompression of the bulbomedullary junction with odontoidectomy was performed. All patients additionally underwent posterior stabilization. Imaging and clinical data were collected in follow-up examinations for 1 year. RESULTS: The bulbomedullary junction was adequately decompressed. No problems due to swelling of pharyngeal soft tissue occurred. One patient required revision due to secondary bleeding. No other complications were observed. All patients had a good clinical outcome with stable regression of the myelopathy symptoms and/or healing of the infection. The imaging follow-up showed sufficient decompression of bone and soft tissue in all cases. No evidence was found of increasing instability or failure of posterior fusion. CONCLUSION: In the operated patients, the full-endoscopic uniportal surgical technique with anterior retropharyngeal approach was found to be a sufficient and minimally invasive method with the known advantages of an endoscopic procedure under continuous irrigation. It should not be viewed only as competition for other surgical techniques - due to its individual technical parameters, it can also be considered to be an alternative or complementary procedure. LEVEL OF EVIDENCE: 4.

Full-endoscopic uniportal decompression in disc herniations and stenosis of the thoracic spine using the interlaminar, extraforaminal, or transthoracic retropleural approach.

OBJECTIVE Surgery for thoracic disc herniation and spinal canal stenosis is comparatively rare and often challenging. Individual planning and various surgical techniques and approaches are required. The key factors for selecting the technique and approach are anatomical location, consistency of the pathology, general condition of the patient, and the surgeon's experience. The objective of the study was to evaluate the technical implementation and outcomes of a full-endoscopic uniportal technique via the interlaminar, extraforaminal, or transthoracic retropleural approach in patients with symptomatic disc herniation and stenosis of the thoracic spine, taking specific advantages and disadvantages and literature into consideration. METHODS Between 2009 and 2015, decompression was performed in 55 patients with thoracic disc herniation or stenosis using a full-endoscopic uniportal technique via an interlaminar, extraforaminal, or transthoracic retropleural approach. Imaging and clinical data were collected during follow-up examinations for 18 months. RESULTS Sufficient decompression was achieved in the full-endoscopic uniportal technique. One patient required revision due to secondary bleeding, and another exhibited persistent deterioration on myelopathy. No other serious complications were observed. All but one patient experienced regression or improvement of their symptoms. CONCLUSIONS The full-endoscopic uniportal technique with an interlaminar, extraforaminal, or transthoracic retropleural approach was found to be a sufficient and minimally invasive method. To cover the entire range of thoracic disc herniations and stenosis within the criteria named, all full-endoscopic approaches are required.

Classification of Osteoporotic Thoracolumbar Spine Fractures: Recommendations of the Spine Section of the German Society for Orthopaedics and Trauma (DGOU).

STUDY DESIGN: Expert opinion. OBJECTIVES: Osteoporotic vertebral fractures are of increasing medical importance. For an adequate treatment strategy, an easy and reliable classification is needed. METHODS: The working group "Osteoporotic Fractures" of the Spine Section of the German Society for Orthopaedics and Trauma (DGOU) has developed a classification system (OF classification) for osteoporotic thoracolumbar fractures. The consensus decision followed an established pathway including review of the current literature. RESULTS: The OF classification consists of 5 groups: OF 1, no vertebral deformation (vertebral edema); OF 2, deformation with no or minor (<1/5) involvement of the posterior wall; OF 3, deformation with distinct involvement (>1/5) of the posterior wall; OF 4, loss of integrity of the vertebral frame or vertebral body collapse or pincer-type fracture; OF 5, injuries with distraction or rotation. The interobserver reliability was substantial (κ = .63). CONCLUSIONS: The proposed OF classification is easy to use and provides superior clinical differentiation of the typical osteoporotic fracture morphologies.

ChromoShake: a chromosome dynamics simulator reveals that chromatin loops stiffen centromeric chromatin.

ChromoShake is a three-dimensional simulator designed to find the thermodynamically favored states for given chromosome geometries. The simulator has been applied to a geometric model based on experimentally determined positions and fluctuations of DNA and the distribution of cohesin and condensin in the budding yeast centromere. Simulations of chromatin in differing initial configurations reveal novel principles for understanding the structure and function of a eukaryotic centromere. The entropic position of DNA loops mirrors their experimental position, consistent with their radial displacement from the spindle axis. The barrel-like distribution of cohesin complexes surrounding the central spindle in metaphase is a consequence of the size of the DNA loops within the pericentromere to which cohesin is bound. Linkage between DNA loops of different centromeres is requisite to recapitulate experimentally determined correlations in DNA motion. The consequences of radial loops and cohesin and condensin binding are to stiffen the DNA along the spindle axis, imparting an active function to the centromere in mitosis.

A New Electromagnetic Navigation System for Pedicle Screws Placement: A Human Cadaver Study at the Lumbar Spine.

INTRODUCTION: Technical developments for improving the safety and accuracy of pedicle screw placement play an increasingly important role in spine surgery. In addition to the standard techniques of free-hand placement and fluoroscopic navigation, the rate of complications is reduced by 3D fluoroscopy, cone-beam CT, intraoperative CT/MRI, and various other navigation techniques. Another important aspect that should be emphasized is the reduction of intraoperative radiation exposure for personnel and patient. The aim of this study was to investigate the accuracy of a new navigation system for the spine based on an electromagnetic field. MATERIAL AND METHOD: Twenty pedicle screws were placed in the lumbar spine of human cadavers using EMF navigation. Navigation was based on data from a preoperative thin-slice CT scan. The cadavers were positioned on a special field generator and the system was matched using a patient tracker on the spinous process. Navigation was conducted using especially developed instruments that can be tracked in the electromagnetic field. Another thin-slice CT scan was made postoperatively to assess the result. The evaluation included the position of the screws in the direction of trajectory and any injury to the surrounding cortical bone. The results were classified in 5 groups: grade 1: ideal screw position in the center of the pedicle with no cortical bone injury; grade 2: acceptable screw position, cortical bone injury with cortical penetration ≤ 2 mm; grade 3: cortical bone injury with cortical penetration 2,1-4 mm, grad 4: cortical bone injury with cortical penetration 4,1-6 mm, grade 5: cortical bone injury with cortical penetration >6 mm. RESULTS: The initial evaluation of the system showed good accuracy for the lumbar spine (65% grade 1, 20% grade 2, 15% grade 3, 0% grade 4, 0% grade 5). A comparison of the initial results with other navigation techniques in literature (CT navigation, 2D fluoroscopic navigation) shows that the accuracy of this system is comparable. CONCLUSION: EMF navigation offers a high accuracy in Pedicle screw placement with additional advantages compared to other techniques. The short set-up time and easy handling of EMF navigation should be emphasized. Additional advantages are the absence of intraoperative radiation exposure for the operator and surgical team in the current set-up and the operator's free mobility without interfering with navigation. Further studies with navigation at higher levels of the spine, larger numbers of cases and studies with control group are planned.

Bilateral spinal decompression of lumbar central stenosis with the full-endoscopic interlaminar versus microsurgical laminotomy technique: a prospective, randomized, controlled study.

BACKGROUND: Extensive decompression with laminectomy, where appropriate, is often still described as the method of choice when operating on degenerative lumbar spinal stenosis. Nonetheless, tissue-sparing procedures are becoming more common. Endoscopic techniques have become the standard in many areas because of the surgical advantages they offer and the benefits for rehabilitation. One key issue when operating on the spine was the development of instruments to provide sufficient bone resection under continuous visual control. This was achieved by using endoscopes for operations carried out in cases of spinal canal stenosis. OBJECTIVE: This study of patients with degenerative lumbar central spinal stenosis compares the results of spinal decompression using the full-endoscopic interlaminar technique (FI) with a conventional microsurgical laminotomy technique (MI). STUDY DESIGN: Prospective, randomized, controlled study. SETTINGS: 135 patients with microsurgical or full-endoscopic decompression were followed up for 2 years. Alongside general and specific parameters, the following measuring instruments were also used for the investigation: Visual Analog Scale (VAS), German version of the North American Spine Society Instrument (NASS), Oswestry Low-Back-Pain-Disability Questionnaire (ODI). RESULTS: Postoperatively 72 % of the patients no longer had leg pain or the pain was almost completely reduced and 21.2 % experienced occasional pain. The clinical results were the same in both groups. The rate of complications and revisions was significantly reduced in the FI Group. The full-endoscopic techniques brought advantages in the following areas: operation, complications, traumatization, rehabilitation. LIMITATIONS: Lack of placebo control group. CONCLUSIONS: The recorded results demonstrate that the full-endoscopic interlaminar bilateral decompression adopting a unilateral approach provides an adequate and safe supplement and alternative to the conventional microsurgical bilateral laminotomy technique when the indication criteria are fulfilled. At the same time, it offers the advantages of a minimally invasive intervention.

Navigation of pedicle screws in the thoracic spine with a new electromagnetic navigation system: a human cadaver study.

INTRODUCTION: Posterior stabilization of the spine is a standard procedure in spinal surgery. In addition to the standard techniques, several new techniques have been developed. The objective of this cadaveric study was to examine the accuracy of a new electromagnetic navigation system for instrumentation of pedicle screws in the spine. MATERIAL AND METHOD: Forty-eight pedicle screws were inserted in the thoracic spine of human cadavers using EMF navigation and instruments developed especially for electromagnetic navigation. The screw position was assessed postoperatively by a CT scan. RESULTS: The screws were classified into 3 groups: grade 1 = ideal position; grade 2 = cortical penetration <2 mm; grade 3 = cortical penetration ≥2 mm. The initial evaluation of the system showed satisfied positioning for the thoracic spine; 37 of 48 screws (77.1%, 95% confidence interval [62.7%, 88%]) were classified as group 1 or 2. DISCUSSION: The screw placement was satisfactory. The initial results show that there is room for improvement with some changes needed. The ease of use and short setup times should be pointed out. Instrumentation is achieved without restricting the operator's mobility during navigation. CONCLUSION: The results indicate a good placement technique for pedicle screws. Big advantages are the easy handling of the system.

Serum derived from multiple trauma patients promotes the differentiation of endothelial progenitor cells in vitro: possible role of transforming growth factor-beta1 and vascular endothelial growth factor165.

Ischemia in various organs and tissues takes place during and as a direct result of multiple trauma (MT). Bone marrow-derived endothelial progenitor cells (EPCs) are involved in neovascularization after ischemic incidences. Here, we report that serum derived from patients with MT stimulates differentiation of EPCs in vitro from peripheral blood mononuclear cells (PBMCs). EPCs were identified by DiL-Acetyl-LDL-uptake with concomitant UEA-I-lectin binding. A significant increase in EPC numbers was noted when PBMCs were cultivated for 72 h with the serum of MT patients (n = 25) obtained at 5 days. Furthermore, serum from MT patients enhanced the functional acting of EPCs to form prevascular structures in matrigel. Reverse transcription polymerase chain reaction analysis revealed gene expression of transforming growth factor (TGF)-beta1- and vascular endothelial growth factor (VEGF) receptors 1 and 2. Reverse transcription polymerase chain reaction analysis was based on further cultivated cell preparations, which contained at least 80% EPCs. Moreover, the addition of recombinant VEGF or low concentrations of TGF-beta increased EPC differentiation. In addition, neutralization of TGF-beta1 and of VEGF165 in MT serum using specific antibodies resulted in a significant decrease in EPC differentiation. Our data indicate that TGF-beta1 and VEGF165 play a pivotal role for EPC differentiation induced by serum of polytrauma patients.