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Background Pulmonary diseases have considerable prognostic relevance for all-cause mortality. Most patients with lung diseases such as chronic obstructive pulmonary disease are treated by general practitioners. Understanding the clinical consequences such as pulmonary hyperinflation or reduced diffusion capacity is important for the management and prognosis of patients with chronic respiratory disorders. Therefore, the interpretation of pulmonary function testing (PFT) results needs to see more emphasis in the medical education curriculum. Objective To develop PFT training for final-year medical students and to compare the efficacy of instructional training to self-reliant textbook study. Methods A two-armed randomized control trial compares learning outcomes in PFT interpretation. A total of 25 final-year medical students were selected at random into the 1) instructional training group or 2) self-reliant textbook study group on PFT interpretation. The learning time for both groups was 2 hours. The duration of the written pre- and post-training examinations was 60 minutes each. Both exams had a knowledge section (30 questions, maximum 120 points) and a skills section (11 case studies, maximum 75 points). Results The instructional training group acquired significantly more knowledge and, in particular, higher skill levels when compared with the self-reliant reading group. In the reading group, knowledge scores increased from 48 to 60% (12%) and skills scores increased from 14 to 22% (8%), whereas in the instructional group, knowledge increased from 47 to 71% (24%) and skills from 18 to 58% (40%). A multivariate analysis (Pillai’s Trace: 0.633; P

INTRODUCTION The objectives of this study are to analyze the impact of cleft palate (CP) on upper airway obstruction using polysomnography in patients with Pierre Robin Sequence (PRS) undergoing mandibular distraction osteogenesis (MDO) and subsequent CP repair. METHODS A single-surgeon, retrospective chart review was performed of all patients with nonsyndromic PRS treated with MDO. Severity of upper airway obstruction was evaluated pre- and post-distraction via polysomnography. Details of MDO and CP repair were collected and any complications recorded. RESULTS Twenty-one nonsyndromic PRS patients with CP and 6 patients without CP met inclusion criteria. There was no significant difference in predistraction apnea-hypopnea index between the 2 groups (53.4 ± 42.1 versus 34.4 ± 18.9; P = 0.3). Patients with CP had significantly higher predistraction SpO2 saturation (94.5 ± 1.6% versus 91.0% ± 4.8%; P = 0.01), SpO2 nadir (74.5% ± 9.1% versus 63.6% ± 11.6%; P = 0.03) and lower percentage time spent below 90% SpO2 (6.0% ± 7.2% versus 23.6% ± 29.9%; P = 0.04). The rate of oronasal fistulas formation was 38%. The time between MDO and CP repair was shorter for patients with complications (250.8 ± 3.3 versus 370.8 ± 191.9 days; P = 0.08). Five patients experienced relapse of respiratory difficulties after CP repair. CONCLUSIONS The presence of CP in nonsyndromic PRS patients decreases the severity of obstructive sleep apnea by oxygen parameters on PSG. Palatal fistulas and relapse of respiratory distress are common complications of CP repair following MDO. Delaying CP repair may help to decrease complication rates.

The macrophage capping protein CAPG belongs to the gelsolin superfamily which modulates actin dynamics by capping the growing end of actin filaments in a Ca2+- and PIP2-dependent manner resulting in polymerization inhibition of actin filaments. In the last years, additional functions for CAPG in transcription regulation were described and higher CAPG amounts have been linked to increased invasiveness and migration behavior in different human tumor entities like e.g. glioblastoma. Nevertheless, there is a lack of knowledge how additional functions of CAPG are regulated. As CAPG contains several cysteine residues which may be accessible to oxidation we were especially interested to investigate how alterations in the cysteine oxidation state may influence the function, localization, and regulation of CAPG. In the present study, we provide strong evidence that CAPG is a redox-sensitive protein and identified two cysteines: C282 and C290 as reversibly oxidized in glioblastoma cell lines. Whereas no evidence could be found that the canonical actin capping function of CAPG is redox-regulated, our results point to a novel role of the identified cysteines in the regulation of cell migration. Along with this, we found a localization shift out of the nucleus of CAPG and RAVER1, a potential interaction partner identified in our study which might explain the observed altered cell migration properties. The newly identified redox sensitive cysteines of CAPG could perspectively be considered as new targets for controlling tumor invasive properties.

This article presents the results of a dissection series investigating a previously neglected ligamentous structure attached to the human occipital bone, the Ligamentum condylicum posterius or posterior condylar ligament, and relates these results to the manifestation of a likewise poorly recognized occipital bony variation, the Processus condylicus posterior. The dissection of 50 human cranio-cervical junctions revealed the existence of the posterior condylar ligament in 98% of all cases, sometimes containing free elongated ossicles and osseous spurs at the insertion points at the occipital bone. In two cases the osseous formation of a Processus condylicus posterior became apparent (4%), which further provided the opportunity to study the behaviour of the ligament in these cases. In this article, we show and discuss that the posterior condylar ligament and osseous structures possibly derive from tissue that originates from the material of the dorsal arch of the Proatlas, a rudimentary vertebra between occipital bone and atlas. For this purpose, the Ponticulus atlantis posterior as another Proatlas-manifestation, whose origin from the dorsal Proatlas-arch is widely accepted in literature, is considered. This bony variant was found in 11 specimens (22%) in the present study and further served to classify and interpret the findings of the much rarer Processus condylicus posterior. As a result of this dissection series and a review of literature on this understudied topic, a typology of manifestations of the posterior condylar ligament, Processus condylicus posterior and related structures like free ossicles has been introduced.

The bilateral sagittal split osteotomy (BSSO) and high oblique sagittal split osteotomy (HSSO) are common techniques for mandibular movement in orthognathic surgery. The aim of this study was to evaluate the influence of both techniques, as well as movement distances and directions, on the position of the temporomandibular joint (TMJ). A total of 80 mandibular movements were performed on 20 fresh human cadaver heads, four on each head. Pre- and postoperative cone beam computed tomography was used to plan the surgical procedure and analyse the TMJ. Reference measurements included the anterior, superior, and posterior joint spaces, intercondylar distances and angles in the axial and coronal planes, and the sagittal, coronal, and axial angulations of the proximal segment. Only minor differences were found between the BSSO and HSSO techniques, particularly in terms of the intercondylar angle in the axial plane (P 0.03) and the condylar angle of the proximal segment in the sagittal plane (P 0.011). Observed changes in the TMJ were mostly opposite when moving the mandible forwards and backwards and increased with increasing movement distance. BSSO and HSSO result in similar changes in TMJ position. The extent of the movement distance influences the position of the condyle more than the osteotomy technique.

BMC musculoskeletal disorders 22, 250 (2021). doi:10.1186/s12891-021-04112-z, Published by BioMed Central, London

Background: The objective of this study was to analyze and report our experience with using polysomnography (PSG) during the early consolidation phase of mandibular distraction osteogenesis (MDO) in patients with Pierre Robin Sequence and associated tongue-based airway obstruction with management decisions informed by the results. The secondary objective was to determine whether pre-operative PSG can predict which patients will have persistent obstructive sleep apnea (OSA) and require additional distraction. Methods: A single-surgeon, retrospective review was performed of all patients who underwent MDO for treatment of tongue-based airway obstruction over an 11-year period. Pre-operative and post-distraction 16-channel overnight bedside PSG was performed on all patients and scored according to the AASM Scoring Manual. Patients who demonstrated persistent OSA underwent further distraction and were reevaluated by PSG after final distraction length was achieved. Results: Pre-operative and post-distraction PSG was obtained and available for analysis in 37 patients. Apnea-Hypopnea Index (AHI) improved from 45.85 ± 34.41 to 9.73 ± 10.85 ( P 2. There was no significant difference in patient characteristics or pre-operative symptoms between the 2 groups. Conclusions: PSG can be performed at the bedside at the end of the distraction phase of MDO to assess for residual airway obstruction and inform the need for further distraction. Pre-operative PSG measures can help predict the need for further distraction and aid in operative planning and distractor placement.

Experimental dermatology 30(5), 745-750 (2021). doi:10.1111/exd.14266, Published by Blackwell, Oxford

The influence of non-smooth trachea walls on phonation onset and offset pressures and the fundamental frequency of oscillation were experimentally investigated for three different synthetic vocal fold models. Three models of the trachea were compared: a cylindrical tube (smooth walls) and wavy-walled tubes with ripple depths of 1 and 2 mm. Threshold pressures for the onset and offset of phonation were measured at the lower and upper ends of each trachea tube. All measurements were performed both with and without a supraglottal resonator. While the fundamental frequency was not affected by non-smooth trachea walls, the phonation onset and offset pressures measured right below the glottis decreased with an increasing ripple depth of the trachea walls (up to 20% for 2 mm ripples). This effect was independent from the type of glottis model and the presence of a supraglottal resonator. The pressures at the lower end of the trachea and the average volume velocities showed a tendency to decrease with an increasing ripple depth of the trachea walls but to a much smaller extent. These results indicate that the subglottal geometry and the flow conditions in the trachea can substantially affect the oscillation of synthetic vocal folds.

Background Gentle and precise tissue dissection reduces collateral tissue damage and preserves its structural quality for optimizing healing. This is particularly true for peripheral nerve neurorrhaphy. Axon regeneration kinetics across the repair is dependent on the amount of intraneural fibrosis. The purpose of this study was to determine whether scalpel blade smoothness was a deterministic factor in the kinetics of postneurorrhaphy peripheral axon regeneration. Methods Scalpel transection of the saphenous nerve was performed in 18 female Hartley guinea pigs either by a standard #15 stainless steel scalpel blade or a highly polished version of the same blade. Compound nerve action potential recordings and histochemical assay of neurofilament density proximal and 1 cm distal to the site of nerve transection were quantified postneurorrhaphy at postoperative weeks 5, 9, and 12. Results There was no action potential transmission observed in the distal axons immediately after neurorrhaphy. A substantial acceleration of axonal conduction recovery was observed in nerves transected with polished scalpel blades observed by high compound nerve action potential amplitudes at postneurorrhaphy weeks 5 and 9 (P < .05). In addition, an increased recovery of intra-axonal neurofilament density in nerves transected with polished scalpel blades was observed by postoperative week 5 (P < .05). Conclusion The quality of the scalpel blade is an important determinate of postsurgical healing. Gentle handling of tissue matters., Highlights • Precise nerve resection reduces lateral axonal injury. • Collateral nerve damage increases interneural fibrosis that slows regeneration. • Smoother scalpel blades result in faster structural and functional nerve recovery.

Trauma-mediated peripheral nerve axon injury invariably involves structural alteration of the axonal plasmalemma cell membrane. Increased axonal membrane permeability to electrolytes results in metabolic stress and axonal degeneration if the axon does not seal. Poloxamer 188 (P188) is a linear multiblock copolymer composed of a hydrophobic polyoxypropylene (POP) block in the middle with polyethylene glycol (PEG) blocks on both ends. The central POP block concentrates at sites of cell membrane disruption and catalyzes sealing of disrupted cellular membranes. We tested the hypothesis that intravenously administered P188 (9800 Da, 0.2 mM) can accelerate distal axon recovery after sciatic nerve crush injury using an established axonotemetic model. A crush injury was performed on the sciatic nerve of thirty female Sprague-Dawley rats. Rats were randomized to receive either 0.2 mM P188 or Dextran, administered 1 h after crush injury. Compound nerve action potentials (CNAP) and density of neurofilament distal to the point of injury were analyzed on post-crush day (PCD) 4, 14, and 21. A significant improvement in axonal conduction for animals treated with P188 was observed for PCD 4 and PCD 14 (p

Clinical neuroradiology 32(2), 325-343 (2022). doi:10.1007/s00062-021-01093-3, Published by Urban & Vogel, München

Cell-cell interactions underlie diverse physiological processes yet remain challenging to examine with conventional imaging tools. Here we report a novel strategy to illuminate cell proximity using transcriptional activators. We repurposed cumate, a small molecule inducer of gene expression, by caging its key carboxylate group with a nitrile. Nitrilase-expressing activator cells released the cage, liberating cumate for consumption by reporter cells. Reporter cells comprising a cumate-responsive switch expressed a target gene when in close proximity to the activator cells. Overall, this strategy provides a versatile platform to image and potentially manipulate cellular interactions over time.

Highlights • Thoracic outlet Syndrome is a very rare disorder caused by compression of the neurovascular structures in the upper thoracic region, SAPHO Syndrom is also a rare Syndrom which causes compression of the subclavian vein in the upper thoracic region. • The subclavian vein thrombosis as a complication of SAPHO syndrome is due compression caused by the Hyperostosis of the clavicle and the costoclavicular joint. • In TOS, first rib resection widens the space and releases the compression on the neurovascular structures in the upper thoracic region. In the absence of a current therapy to avoid the progression of the hyperostosis of the costoclavicular joint and clavicle, the rib resection offers a surgical therapy to relieve the compression on the subclavian vein. • Resection of the first rib in patients with SAPHO syndrome suffering from compression of the subclavian vein can help in avoiding more vascular damage and can relief the compression on the collateral venous circulation., Introduction and Importance Thoracic outlet syndrome (TOS) includes disorders caused by compression of the neurovascular structures in the upper thoracic outlet (Roos and Owens, 1996 [1]; Bürger, 2014; Curuk, 2020 [3]). Depending on the compressed structure, it is categorized into neurological, arterial and venous TOS. SAPHO syndrome (synovitis–acne–pustulosis–hyperostosis–osteitis syndrome) is a rare chronic inflammatory disease of unknown etiology. With its typical involvement of sternoclavicular joint and clavicle, complication due to hyperostosis in this region, leading to thrombosis of the subclavian vein have been reported in some cases of SAPHO syndrome. Between 2015 and 2019 488 patients, suffering from neurological, vascular or combined TOS presented at our department. Depending on clinical and diagnostic results surgical therapy was performed in 175 cases via the transaxillary approach, including complete first rib and/or cervical rib resection, neurolysis of plexus brachialis, thoracic sympathectomy and vascular reconstruction if indicated (Curuk, 2020). During this period, only one single patient presented with SAPHO syndrome with thrombosis of the subclavian vein and neurovascular TOS. Case presentation We present a 50-year-old female patient, in line with the SCARE 2020 criteria (Agha et al., 2020 [12]) suffering from extremely rare combination of neurovascular TOS and SAPHO syndrome with thrombosis of the left subclavian vein due to hyperostosis of the left clavicle. Conclusion Progressive bone changes associated with SAPHO syndrome can lead to narrowing of the thoracic outlet. Pharmacological therapies to avoid the progression of the hyperostosis of the costoclavicular joint and the clavicle do currently not exist. First rib resection is a therapeutic option to widen the space in the upper thoracic region. Surely, it is a rare condition and more long-term follow-up data are required.

Cells secrete proteins to communicate with their environment. Therefore, it is interesting to characterize the proteins which are released from cells under certain experimental conditions the so-called secretome. Here, often proteins from conditioned medium of cultured cells are analyzed, but these additionally might include also contaminating proteins of serum that have not been sufficiently removed or proteins from dying cells. To provide high-quality secretome data and minimize potential contaminants, we describe a quantitative comparison of conditioned medium and the cellular proteome. The described workflow comprises cell cultivation, sample preparation, and final data analysis which is based on the comparison of data from label-free mass spectrometric quantification of proteins from the conditioned medium with corresponding cellular proteomes enabling the detection of bona fide secreted proteins.

The hip joint plays a very important role in the dynamic physiology of the locomotor system and presents numerous anatomical details and peculiarities, which can be essential for hip surgery. This joint is the largest spheroidal articulation of the human body, composed of the femoral head and the opposing acetabulum of the innominate bone. The acetabulum encloses the head somewhat over its equator, so that we have a special kind of the spheroidal joint, the so-called cotyloid articulation or enarthrosis.

International urogynecology journal (2020). doi:10.1007/s00192-020-04609-6, Published by Springer, London [u.a]

Background The incidence of periprosthetic fractures of the proximal humerus is gradually increasing, following an increase in reverse shoulder arthroplasties in recent years. Locking plate fixation and revision arthroplasty are both valuable treatment methods. However, the primary stability of fixation methods for periprosthetic fractures has not been investigated in detail. The aim of this study was to analyze and compare the primary stability of the common treatment measures. Materials and methods Cemented reverse total shoulder arthroplasty (Delta Xtend; DePuy Synthes, Warsaw, IN, USA) was performed in 5 shoulders, and a distal, mid-diaphysis humeral fracture (Wright and Cofield type B) was induced. The implant was left in place, and 3 distinct fixation scenarios were tested: osteosynthesis using 4.5-mm locking plate fixation (subgroup A), 4.5-mm locking plate fixation with an additional 3.5-mm locking plate (subgroup B), and 4.5-mm locking plate fixation with an additional K-wire cerclage (subgroup C). The specimens were tested in a biomechanical setup simulating activities of daily living including rotation. Strain gauges (4-wire strain at 120 Ω; Vishay Measurements Group, Chartres, France) mounted on the 4.5-mm locking plates were used to evaluate the strain of the fixation and to give an estimate of primary stability. Results Regarding the simulation of activities of daily living, no statistically significant differences were found in the measured strains on the locking plate between subgroups A, B, and C. A maximum measured strain of 216.85 μm/m in subgroup A resulted in bending of the locking plate (length, 134 mm) of 0.03 mm. In subgroup B (277.01 μm/m), the plate strained 0.04 mm compared with a strain measurement of 0.01 mm in subgroup C (75.93 μm/m). Conclusion Additional K-wire cerclages or additional 3.5-mm locked plating did not increase primary stability. With a stable prosthetic implant in place, 4.5-mm locked plating is sufficient to address periprosthetic humeral shaft fractures in the present in vitro setup.

Magnetic resonance imaging (MRI) under mechanical loading, commonly referred to as stress MRI, allows the evaluation of functional properties of intra- and periarticular tissues non-invasively beyond static assessment. Quantitative MRI can identify physiological and pathological responses to loading as indication of, potentially treatable, early degeneration and load transmission failure. Therefore, we have developed and validated an MRI-compatible pressure-controlled axial loading device to compress human knee specimens under variable loading intensity and axis deviation. Ten structurally intact human knee specimens (mean age 83.2 years) were studied on a 3.0T scanner (Achieva, Philips). Proton density-weighted fat-saturated turbo spin-echo and high-resolution 3D water selective 3D gradient-echo MRI scans were acquired sequentially at 10° joint flexion in seven configurations: unloaded and then at approximately half and full body weight loading in neutral, 10° varus and 10° valgus alignment, respectively. Following manual segmentation in both femorotibial compartments, cartilage thickness (ThC) was determined as well as meniscus extrusion (ExM). These measures were compared to computed tomography scans, histological grading (Mankin and Pauli scores), and biomechanical properties (Instantaneous Young's Modulus). Compartmental, regional and subregional changes in ThC and ExM were reflective of loading intensity and joint alignment, with the greatest changes observed in the medial compartment during varus and in the lateral compartment during valgus loading. These were not significantly associated with the histological tissue status or biomechanical properties. In conclusion, this study explores the physiological in-situ response of knee cartilage and meniscus, based on stress MRI, and as a function of loading intensity, joint alignment, histological tissue status, and biomechanical properties, as another step towards clinical implementation.

Computed tomographic angiography (CTA) is reported to give insight into patient-specific anatomy of the flap pedicle preoperatively. We compared information available from standard CTA (s-CTA) with that gained by modifying the conventional CTA technique (modified CTA [m-CTA]). Dissected cadavers served as the control group.We evaluated 16 s-CTA scans (32 deep circumflex iliac arteries [DCIAs]) and 12 m-CTA scans (17 DCIAs) using 3-dimensional software (Vesalius; ps-medtech, Amsterdam, The Netherlands). We dissected 17 cadavers (n = 34 DCIAs) to serve as the control group. The positions of 4 landmarks (anterior superior iliac spine, origin of DCIA, origin of ascending branch, and crossing of horizontal branch and iliac crest) were defined in a 3-dimensional coordinate system.We found significant differences concerning the distances from the origin of the DCIA to the femoral bifurcation (P .05) and the anterior superior iliac spine to the crossing point of the horizontal branch with the iliac crest (P .05) between CTA scans and cadaveric studies. The imaging quality of the m-CTA scans was shown to be more consistent than and superior to that of the s-CTA scans. The visible length of the DCIA was longer on m-CTA scans (mean, 134.32 mm) than on s-CTA scans (mean, 73.62 mm). We could evaluate the branching off of perforators and the relation of the pedicle to the surrounding bone and soft tissue in more detail on m-CTA scans. Standard CTA allowed the bilateral evaluation of the pedicle, whereas m-CTA allowed the evaluation of the injected side only.The quality and quantity of information available from CTA could be improved by modifying the s-CTA examination by injection as close as possible to the target vessel. Standard CTA delivered information about both sides, whereas m-CTA may need an additional injection for contralateral-side imaging.

BioMed research international 2018, 7189714 (2018). doi:10.1155/2018/7189714, Published by Hindawi, New York [u.a.]

Recent investigations have confirmed an important stabilizing and protective function of the meniscofemoral ligaments (MFLs) to the knee joint and suggest a clinical relevance. Concerning their incidences, however, there have been discrepancies between data acquired from cadaveric studies and MRI data using 0.3- to 1.5-Tesla field strengths probably due to lower resolution. This study aims to investigate whether imaging with 3-Tesla magnetic resonance imaging (3-T MRI) is beneficial in gaining information regarding the ligaments' incidence, length, width and anatomic variation.3-T MRI images of 448 patients (224 males, 224 females, with, respectively, 32 patients of each sex in the age groups: 0-20, 21-30, 31-40, 41-50, 51-60, 61-70,70years) were retrospectively reviewed. The influence of the parameters 'sex' and 'age' was determined.Whereas 71% of the patients had at least one MFL, 22% had an anterior MFL (aMFL), 53% had a posterior MFL (pMFL) and five percent had coexisting ligaments. The pMFLs were more likely to be present in female patients (P0.05) but if so, they were longer in the males (P0.05). The pMFL was categorized according to its insertion on the medial femoral condyle.3-T MRI enables an excellent illustration of the anatomic variations of pMFLs. By modifying an anatomic classification for radiological use we measured lengths and widths of the MFLs without any difficulties. Despite its increased resolution, 3-T MRI lends no diagnostic benefit in visualizing the course of the aMFL or filigree coexisting ligaments as compared to MRI at lower field strengths.

When we use implants the aesthetic appearance of the patient is dependent to a large extent on identification of factors that influence the presence of interdental papillae. The aim of this study was to compare the accuracy of different non-invasive measurements to indicate the top of the interdental papilla on dental radiographs. The sample comprised six fresh, partly edentulous cadavers. The distance from the level of the interproximal bone next to the tip of the papilla was measured (n=330) on standard radiographic images. Five different mixtures of radiopaque markers that had been used to highlight the top of the papilla in recently published studies were analysed. All measurements were compared with the bone probing length, which was evaluated clinically. The mixture of zinc oxide, eugenol cement, and tungsten powder (mean (SD) 0.14 (0.17)mm) deviated least from the control value. The deviation was significant (p

The purpose of this study was to investigate the range-of-motion after posterior polyetheretherketone-based rod stabilisation combined with a dynamic silicone hinge in order to compare it with titanium rigid stabilisation.Five human cadaveric lumbar spines with four vertebra each (L2 to L5) were tested in a temperature adjustable spine-testing set-up in four trials: (1) native measurement; (2) kinematics after rigid monosegmental titanium rod instrumentation with anterior intervertebral bracing of the segment L4/5; (3) kinematics after hybrid posterior polyetheretherketone rod instrumentation combined with a silicone hinge within the adjacent level (L3/4) and (4) kinematics after additional decompression with laminectomy of L4 and bilateral resection of the inferior articular processes (L3). During all steps, the specimens were loaded quasi-statically with 1°/s with pure moment up to 7.5Nm in flexion/extension, lateral bending and axial rotation.In comparison to the native cadaveric spine, both the titanium device and polyetheretherketone-based device reduce the range-of-motion within the level L4/5 significantly (flexion/extension: reduction of 77%, p0.001; lateral bending: reduction of 62%, p0.001; axial rotation: reduction of 71%, p0.001). There was a clear stabilisation effect after hybrid-instrumentation within the level L3/4, especially in flexion/extension (64%, p0.001) and lateral bending (62%, p0.001) but without any effect on the axial rotation. Any temperature dependency has not been observed.Surprisingly, the hybrid device compensates for laminectomy L4 and destabilising procedure within the level L3/4 in comparison to other implants. Further studies must be performed to show its effectiveness regarding the adjacent segment instability.

INTRODUCTION PMMA-augmentation of pedicle screws strengthens the bone-screw-interface reducing cut-out risk. Injection of fluid cement bears a higher risk of extravasation, with difficulty of application because of inconsistent viscosity and limited injection time. OBJECTIVE To test a new method of cement augmentation of pedicle screws using radiofrequency-activated PMMA, which is suspected to be easier to apply and have less extravasations. METHODS Twenty-seven fresh-frozen human cadaver lumbar spines were divided into 18 osteoporotic (BMD ≤ 0.8 g/cm2) and 9 non-osteoporotic (BMD > 0.8 g/cm2) vertebral bodies. Bipedicular cannulated pedicle screws were implanted into the vertebral bodies; right screws were augmented with ultra-high viscosity PMMA, whereas un-cemented left pedicle screws served as negative controls. Cement distribution was controlled with fluoroscopy and CT scans. Axial pullout forces of the screws were measured with a material testing machine, and results were analyzed statistically. RESULTS Fluoroscopy and CT scans showed that in all cases an adequately big cement depot with homogenous form and no signs of extravasation was injected. Pullout forces showed significant differences (p < 0.001) between the augmented and non-augmented pedicle screws for bone densities below 0.8 g/cm2 (661.9 N ± 439) and over 0.8 g/cm2 (744.9 N ± 415). CONCLUSIONS Pullout-forces were significantly increased in osteoporotic as well as in non-osteoporotic vertebral bodies without a significant difference between these groups using this standardized, simple procedure with increased control and less complications like extravasation.

ZusammenfassungGegenstand und Ziel: Die Hüftgelenkskapsel unterliegt bei der Hüftgelenksdysplasie (HD) erhöhten Zugkräften, die zu einer Entzündung des Kapselgewebes führen. Eine entzündungsassoziierte Zunahme der Nervenverteilungsdichte wurde in verschiedenen Organen nachgewiesen und könnte auch im Rahmen einer HD Ursache für Hüftgelenksschmerz und Koxarthrose sein. Ziel dieser Studie war, bei Hunden mit normo- bzw. dysplastischen Hüftgelenken Unterschiede in der Nervenverteilungsdichte innerhalb der Hüftgelenkskapsel aufzuzeigen. Material und Methoden: Bei 16 aus anderen Gründen euthanasierten Labrador Retrievern erfolgte anhand des radiologischen Befunds eine Kate gorisierung der Hüftgelenke als normoplastisch (Gruppe 1, n = 18) oder dysplastisch (Gruppe 2, n = 14). Die histologischen Präparate der Hüftgelenkskapseln wurden nach Färbung der Nerven fasern mit der Sihler-Färbemethode eingescannt und mittels einer Matrix in 10 gleich große Quadranten, nummeriert von dorsomedial (Q01) nach kraniodorsolateral (Q10), unterteilt. Durch Berechnung des prozentualen Anteils schwarzer Pixel mittels halbautomatischer Bildanalyse wurde die Nervenverteilungsdichte für jeweils das gesamte Präparat und die einzelnen Quadranten analysiert. Der statistische Vergleich erfolgte mittels t-Test für unabhängige Stichproben. Ergebnisse: Bei Hunden mit HD zeigte sich im kraniodorsolateralen Anteil der Hüftgelenkskapsel eine signifikant höhere Nervenverteilungsdichte (p = 0,03). Die mittlere Nervenverteilungsdichte für die gesamte Hüftgelenkskapsel differierte zwischen den beiden Gruppen nicht signifikant. Schlussfolgerung: Eine erhöhte Nervenverteilungsdichte im kraniodorsalen Anteil der Hüftgelenkskapsel bei Hunden mit HD könnte Folge der großen Zugkräfte in diesem Bereich und eine Ursache für die mit der HD einhergehende Schmerzhaftigkeit und Koxarthrose sein. Klinische Relevanz: Die Ergebnisse liefern die pathophysiologische Grundlage für den Erfolg der Deperiostierung des kranialen Azetabulumrandes im Rahmen einer Hüftgelenksdenervation zur Erzielung einer suffizienten Schmerzlinderung und Entzündungsreduktion bei Hunden mit HD.

Background Screw loosening is a major complication following spondylodesis. While several modifications increase screw stability, some, such as screw augmentation, are associated with potential complications; new techniques are needed to minimize the risk of screw loosening without increasing complication rates. Methods 13 fresh-frozen human lumbar vertebral bodies (L1 to L5) were dissected. In group 1 (n = 7), pedicle screws were implanted conventionally, while in group 2 (n = 6), the screws were positioned divergent in the sagittal pathway. Screw stability was tested under cyclic axial load; one testing-cycle included 1000 repetitions. The first cycle started with a load of 100 N while the load was increased by +20 N in each following cycle until failure. Failure was defined by either a >5 mm movement of the screw heads or triggering of the switch-off threshold. Findings Average number of cycles until failure was increased in group 2 compared with group 1 (12,046 vs 9761 cycles), as was the average load to failure (Fmax 313 N vs 260 N). Overall, in group 2, the number of cycles until screw loosening or failure increased by 23% (p = 0.28), while the required force increased by 20% (p = 0.3). Statistically significant correlation between BMD and increased number of cycles completed as well as with increased load (p Interpretation The results demonstrate, that divergent screw-drift of pairs of screws in the sagittal plane tends to increase stability, especially in vertebral bodies with lower bone density. Moreover, we could demonstrate a correlation between BMD and stability of screw-fixation.

Background Bicortical screw fixation is an established technique to increase screw strength in vertebral bodies, although it is associated with several complications, for example screw-loosening. Cement augmentation can increase stability of screw-fixation but can also cause various complications, such as cement-leakage or cement embolism. In this study, we tested a new, multicortical screw fixation technique in the sacrum. Methods Four fresh-frozen sacrums were used. In group 1, standard screw insertion, with sagittal parallel and axial convergent screw-drive was performed. In group 2, the screw-drive of the first screw was similar to the screw-drive in group 1. In addition, a second screw was inserted descending into the intended hole in the head of the screw and at a stable angle. Therefore, the screws of the multiloc humerus nail-system (Synthes) were used. The specimens were connected to a testing-machine and underwent cyclic axial loading with an increase in the load after each completed stage. Findings Multicortical screw fixation leads to a significant increase in the number of completed cycles and a significantly increased load until failure. Interpretation Multicortical screw fixation in the sacrum offers a stronger attachment of the screws. In the future, multicortical implants, which fulfil the criteria demanded in spine surgery, can offer higher stability and may decrease the loosening rates of the implanted screws.

International journal of environmental research and public health : IJERPH 18(8), 4344 (2021). doi:10.3390/ijerph18084344, Published by MDPI AG, Basel

A variety of donor sites are available for mandibular reconstruction. We present here a different way of comparing two commonly-used bone flaps. The lengths of the usable parts in a total of 241 coxal bones, 91 mandibles and 60 fibulas were measured. The mandible was measured from condyle-to-condyle and the harvestable bone length (HBL) and usable (UBL) bone lengths in fibula and ilium were also measured. The bone thickness (BT) in 60 iliac crests was measured in two parallel lines from the anterior superior iliac spine (ASIS) along the iliac crest. The mandible was 32.17 mm shorter in females than in males. The total ilium UBL was 171.12 mm in females and 178.80 mm in males. The mean HBL of the fibula was 22.6 mm shorter in females than in males. However, in some fibulas in both females and males, only 4.2% and 21.1% of the HBL respectively could be used if the ultimate goal was to insert dental implants. We found significant correlations between BT and gender in both fibula and ilium (P≤ 0.05). The ilium offers constant BT throughout the usable bone area with a similar bone length to the fibula. In contrast, the fibula showed variable bone dimensions, so not all of it is clinically usable. This should especially be considered in females when a mandibular reconstruction is planned with the goal of occlusal rehabilitation. Clin. Anat. 29:773-778, 2016. © 2016 Wiley Periodicals, Inc.

Introduction: Cancer metastasis is a complex process involving the spread of malignant cells from a primary tumor to distal organs. Understanding this cascade at a mechanistic level could provide critical new insights into the disease and potentially reveal new avenues for treatment. Transcriptome profiling of spontaneous cancer models is an attractive method to examine the dynamic changes accompanying tumor cell spread. However, such studies are complicated by the underlying heterogeneity of the cell types involved. The purpose of this study was to examine the transcriptomes of metastatic breast cancer cells using the well established MMTV PyMT mouse model. Methods: A suite of organ derived metastatic cell lines were harvested from 10 female PyMT mice and used for transcriptome profiling. The cells were first extracted from mouse organs with metastatic disease. Tissues were processed into single cell suspensions. Cancer cells were isolated and sorted based on the expression of specific cell surface markers. Cells exhibiting CD44low EpCAMhigh or CD44high EpCAMhigh profiles were collected. RNA from each cell line was extracted in biological replicates for bulk RNA sequencing. Samples were sequenced using the NextSeq 500 Illumina platform. Reads were mapped to the mouse genome using STAR and gene expression was quantified using RSEM. Tissue specific genes were compared across the different metastatic and primary tumor samples. Results: Cell lines harvested from PyMT mice were able to recapitulate the metastatic cascade in vivo. Expression of the oncogenic PyMT transgene was observed in all cell lines. Comparison of RNA sequencing data across all cell populations produced distinct gene clusters. Differential gene expression patterns related to organ tropism and immunomodulatory signatures were observed. Furthermore, the sequencing results identified expression profiles based on tissue dependent niches and clonal heterogeneity. These cohorts of data were narrowed down to identify a subset of genes with high expression and known metastatic propensity. These key genes are being used to image specific stages of the metastatic cascade. Conclusion: The collection of organ derived cancer cell lines enabled comprehensive transcriptomic analysis of different metastatic niches. This transcriptome pattern could contribute to subclonal evolution during cancer progression. In future work, we aim to investigate intratumoral heterogeneity by preforming single cell RNA sequencing on key metastatic samples and compare them to the primary tumor. The markers will also be used to image the impact of tumor heterogeneity on metastases. Citation Format: Anastasia A. Ionkina, Gabriela Balderrama-Gutierrez, Steve Huy Phan, Ali Mortazavi, Jennifer A. Prescher. Comparative transcriptome analysis of metastatic heterogeneity in a mouse model of breast cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2496.

Objectives Improved fixation techniques with optional use of bone cements for implant augmentation have been developed to enhance stability and reduce complication rates after osteosynthesis of femoral neck fractures. This biomechanical study aimed to evaluate the effect of cement augmentation on implant anchorage and overall performance of screw-anchor fixation systems in unstable femoral neck fractures. Methods Ten pairs of human cadaveric femora were used to create standardized femoral neck fractures (Pauwels type 3 fractures; AO/OTA 31-B2) with comminution and were fixed by means of a rotationally stable screw-anchor (RoSA) system. The specimens were assigned pairwise to two groups and either augmented with PMMA-based cement (Group 1, augmented) or left without such augmentation (Group 2, control). Biomechanical testing, simulating physiological loading at four distinct load levels, was performed over 10.000 cycles for each level with the use of a multidimensional force-transducer system. Data was analysed by means of motion tracking. Results Stiffness, femoral head rotation, implant migration, femoral neck shortening, and failure load did not differ significantly between the two groups (p ≥ .10). For both groups, the main failure type was dislocation in the frontal plane with consecutive varus collapse). In the cement-augmented specimens, implant migration and femoral neck shortening were significantly dependent on bone mineral density (BMD), with higher values in osteoporotic bones. There was a correlation between failure load and BMD in cement-augmented specimens. Conclusion In screw-anchor fixation of unstable femoral neck fractures, bone-cement augmentation seems to show no additional advantages in regard to stiffness, rotational stability, implant migration, resistance to fracture displacement, femoral neck shortening or failure load.

This study was conducted to compare fracture patterns and operation times after sagittal split osteotomy (SSO) by Hunsuck/Epker approach, performed using a burr or ultrasonic device, with and without osteotomy modification. A total of 80 SSOs were performed in fresh human cadavers using a burr or ultrasonic device to investigate the influence of surgical instruments as well as an additional bone cut on the inferior border of the mandible in terms of lingual fracture patterns. The times required for osteotomy and sagittal split were measured, and postoperative cone beam computed tomography images of all splits were analyzed. Without an additional inferior osteotomy, preferred splits according to Hunsuck/Epker were achieved in 35% of cases (7/20) with the burr and 45% (9/20) with the ultrasonic instrument. The inferior modification resulted in a greater number of unwanted fracture patterns in both groups. There was no relationship between the split technique and the fracture pattern (P=0.7854). Statistically significant differences in osteotomy time were observed between burr osteotomy and modified burr osteotomy (P=0.006), as well as modified ultrasonic osteotomy (P

The aim of this cadaveric study was to measure the transfer accuracy of orthodontic mini-implant placement at the anterior palate depending on tooth-borne or gingiva-borne guide support. Forty orthodontic mini-implants were placed paramedian in the anterior palate of 20 cadaver heads using tooth-borne (TBG) or gingiva-borne guides (GBG). Placement was planned after superimposition of lateral cephalograms and corresponding plaster models. After mini-implant placement, digital impressions were taken with scanbodies. For the measurement of both linear and angle deviations, virtual planning models and postoperative oral scans were compared using automatic surface registration based on an iterative closest point algorithm. Statistical differences between TBG and GBG were detected for lateral deviations 0.88 mm (SD 0.46) versus 1.65 mm (SD 1.03) (p = .004) and sagittal angular deviations 3.67° (SD 2.25) versus 6.46° (SD 5.5) (p = .043). No differences were found for vertical deviations 2.34 mm (SD 0.74) versus 2.14 mm (SD 0.73) (p = .40) and transverse angular deviations 3.60° (SD 2.89) versus 4.06° (SD 3.04) (p = .62). The use of surgical guides based on silicone provides sufficient control of orthodontic mini-implant placement and is comparable to CAD/CAM templates. However, when compared with guided dental implantology, the planned mini-implant position is more inaccurate. However, accuracy can be significantly increased by guide extension involving the teeth. Clinical investigations have to prove if the accuracy is sufficient for receiving an orthodontic appliance. The use of lateral cephalograms and plaster models for silicone guide construction leads to lower radiation exposure and provides sufficient accuracy for palatal orthodontic mini-implant placement.

Die ausere Nase bestimmt wesentlich das asthetische Erscheinungsbild eines Gesichts und ist damit auch fur das Selbstwertgefuhl ihres Tragers verantwortlich. Um die zahlreichen anatomischen Besonderheiten und Variationen, die das harmonische Erscheinungsbild negativ beeinflussen konnen, chirurgisch zu optimieren, ist eine detaillierte Kenntnis der anatomischen Grundbausteine der auseren Nase unbedingt erforderlich. Die ausere Nase wird durch ein knochernes Grundgerust, bestehend aus den Ossa nasalia und den Processus frontales maxillae aufgebaut. Diese Strukturen umfassen die Apertura piriformis, die zahlreiche Formtypen zeigt. Weiterhin kommt dem Nasenseptum eine wesentliche, auch stabilisierende Rolle zu. Die knocherne Grundlage der Nase wird durch die Nasenknorpel, insbesondere den Septumknorpel und die Cartilagines alares majores komplettiert, die fur die Gestaltung der Nasenflugel, der Nasenlocher und der Nasenspitze sehr wichtig sind. Die knochern-knorpelige Grundlage der Nase wird von rudimentaren Muskeln besetzt, die jedoch auch zum Teil noch auf die Form einwirken konnen. Die grosen Arterien verlaufen an der Basis der Nasenpyramide und geben kleinere Aste zu den Seitenpartien, dem Nasenrucken und der Nasenspitze ab.

Cellular communication drives diverse aspects of organismal biology ranging from immune function to memory formation. The mechanisms by which cells transact information in vivo, though, are not completely understood. This is due, in part, to a lack of tools for observing collections of cells in their native habitats. New optical probes are being crafted to image networks of cell-cell interactions (i.e., 'interactomes') in tissues and live organisms. Examples of these probes-and their use in visualizing cell contacts and macroscopic cell networks-are highlighted.

Natural killer cells are able to directly lyse tumor cells, thereby participating in the immune surveillance against cancer. Unfortunately, many cancer cells use immune evasion strategies to avoid their eradication by the immune system. A prominent escape strategy of malignant cells is to camouflage themselves with Siglec-7 ligands, thereby recruiting the inhibitory receptor Siglec-7 expressed on the NK cell surface which subsequently inhibits NK-cell-mediated lysis. Here we describe the synthesis and evaluation of the first, high-affinity low molecular weight Siglec-7 ligands to interfere with cancer cell immune evasion. The compounds are Sialic acid derivatives and bind with low micromolar Kd values to Siglec-7. They display up to a 5000-fold enhanced affinity over the unmodified sialic acid scaffold αMe Neu5Ac, the smallest known natural Siglec-7 ligand. Our results provide a novel immuno-oncology strategy employing natural immunity in the fight against cancers, in particular blocking Siglec-7 with low...

According to the origin and the route of spread of the juvenile angiofibroma, the relevant osseous anatomy of the central skull base and the topography of the neighbouring regions are described. Especially the posterior part of the nasal cavity, the nasopharynx, the pterygopalatine fossa and the infratemporal fossa are the main area of interest. Furthermore some embryological considerations are given, concerning the origin of the juvenile angiofibroma, which can be interpreted as a dysontogenetic tumor.

This study aimed to evaluate the osteometric boundaries of the ilium, fibula, and scapula beyond which reconstruction of oromandibular and craniofacial defects, using these free flaps, may not be optimal. Fibula, scapula, and iliac bones were obtained bilaterally from 33 female and 27 male European adult cadavers (n = 60). Adapting classical anthropometric methods to surgical needs by modifying the measuring bone localizations and measurement points, a measuring system of osteometry and morphometry was used, to quantify the usable bone length of the iliac crest, fibula, and lateral border of the scapula and to localize an oval region (OR) in the ilium. The thin, translucent OR of ilium was localized 62.4 ± 5.6 mm posterior to the maximum concavity between the anterior superior (ASIS) and anterior inferior iliac spine and 26.7 ± 6 mm caudal to the intermediate line of the iliac crest. The available iliac crest was measured from ASIS to the posterior superior iliac spine (PSIS) 247.5 ± 12.6 mm, fibula supplied 170.2 ± 19.1 mm harvestable bone, and the lateral border of the scapula 94.3 ± 8.5 mm [Corrected]. The OR influenced the harvestable bone shape and volume of the ilium. Measuring of the localization points of OR, we found that the size of the OR was very variable and that the height of the neomandible reconstructed with iliac crest might alter with aging. Our findings contribute with knowledge of detailed morphometric measurements on commonly used donor bones to the planning strategies of volumetric defects in oral and maxillofacial region by precise osteometric localization method of OR and relativized length measurements.

Background Pedicle screw pullout due to poor bone quality, mainly caused by osteoporosis, is a common problem in spine surgery. Special implants and techniques, especially PMMA augmentation, were developed to improve the fixation of pedicle screws. PMMA injection into a pilot hole or through a screw involves the same risks as vertebroplasty or kyphoplasty, regardless of the technique used. Especially when using fully cannulated screws anterior leakage is possible. Objective To prove PMMA injection is safe and possible without leakage through an incompletely cannulated screw and also increases pullout forces in the osteoporotic vertebra. Methods Incompletely cannulated pedicle screws were tested by axial pullout in human cadavers, divided into osteoporotic and non-osteoporotic groups. Non-augmented and PMMA-augmented pedicle screws were compared. Twenty-five human vertebrae were measured by DEXA and divided into osteoporotic and non-osteoporotic groups. In each vertebra both pedicles were instrumented with the new screw (WSI-Expertise 6×45 mm, Peter Brehm Inc. Germany); the right screw was augmented with a 3 mL PMMA injection through the screw. On each screw axial pullout was performed after X-ray and CT scan. Results Radiographs and CT scans excluded PMMA leakage. Cement was distributed in the middle and posterior third of the vertebrae. Pullout forces were significantly higher after pedicle screw augmentation, especially in the osteoporotic bone. All augmented pedicle screws showed higher pullout forces compared with the unaugmented screws. Conclusions We minimized the risk of leakage by using a screw with a closed tip. On the whole, PMMA augmentation through an incompletely cannulated pedicle screw is safe and increases pullout forces in osteoporotic bone to the level of healthy bone. Therefore the new incompletely cannulated screw can be used for pedicle screw augmentation.

The scapula free flap is often the first choice for reconstruction of bony defects of the facial skeleton. However, the vascularised rib as part of a free rib osteomyocutaneous flap may be a suitable second choice. We have investigated the morphology and clinical dimensions of the 7th rib and the scapula, and the ability of the available bone to carry dental implants. The age and sex of the cadaver, and the donor side, were also recorded. The dimensions of the scapulas and 7th ribs (n = 130 of each) from 65 cadavers were measured at 4 different points using osteometric methods. Examination showed that bone from the scapula and 7th rib were sufficient for placement of implants. The 7th rib gave reliable measurements for both height and width, and a consistent relation between compact and cancellous bone. Although the scapula provided adequate compact and cancellous bone, there were variations depending on the segment of bone chosen. Bones from male cadavers were more suitable for implantation. In both the scapula and the 7th rib ageing had a significant adverse effect in only one dimension. Most points of measurement have satisfactory bony dimensions for insertion of dental implants. © 2014 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

We assessed the morphological characteristics and dimensions of the ilium and fibula to evaluate the suitability of particular areas of bone for use as donor sites for dental reconstructions that carry implants. We measured the dimensions of 130 bilaterally harvested ilium and fibula bones from 65 adult cadavers using osteometric methods, and analysed the effects of age, sex, and side. Dimensions at measuring points, overall suitability for implantation, and relations among age, sex, and side, were evaluated statistically. We report observations of bone morphology involving cross-sections, and clinical relevance. Although the mean dimensions of the fibula and iliac crest were adequate, some segments would not support an implant 10 mm long and 3.5 mm wide. The overall suitability of parts of the iliac block fell to 30%. Fibular morphology is characterised by constant height and width, and relation of cortical and cancellous bone. Bony dimensions on the iliac fossa and fibula were significantly greater in men than in women. Age had a negative impact in one area of the iliac fossa, but nowhere on the iliac crest. Side was not significant. We found differences in dimensions and morphology between measuring points on the same bone. Precise knowledge about which areas of the donor sites can reliably provide sufficient bone to carry implants after reconstructions will allow greater flexibility and safety when reconstructions are designed. © 2013 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Recent advances in neuroimaging have led to new insights into the organization of language related networks. Increasing evidence supports the model of dorsal and ventral streams of information flow between language-related areas. Therefore, a review of the descriptions of language-related fiber anatomy in the human and monkey brain was performed. In addition, case studies of macroscopical fiber dissection and polarized light imaging (PLI) with special focus on the ventral stream were done. Several fiber structures can be identified to play a role in language, i.e. the arcuate fasciculus as a part of the superior longitudinal fasciculus, the middle longitudinal fasciculus, the inferior fronto-occipital fasciculus, and extreme and external capsules. Substantial differences between human and monkey fiber architecture have been identified. Despite inconsistencies based on different terminologies used, there can be no doubt that dorsal and ventral language streams have a clear correlation in the structure of white matter tracts.

The iliac bone crest is one of the most valuable regions for harvesting bone grafts, both vascularized and nonvascularized. Since the first commendable description of this region as a possible source for vascularized bone flaps by Taylor, little relevant information concerning the variations of the deep circumflex iliac vessels and their relationship to the neighboring structures has been published. The purpose of the current study was to examine this region clinically and anatomically, taking into consideration the former description by Taylor. We gathered all our findings on 216 iliac regions and proposed a new classification. In addition we measured the relationships between the deep circumflex iliac artery and important surgical landmarks. A comparison of our finding with other studies showed similarities and differences but was far more complete. Generally (92%) the deep circumflex iliac artery (DCIA) originated from external iliac artery (EIA) behind the inguinal ligament (IL) and passed cranio-laterally toward the anterior superior iliac spine, where it divided into two important branches. Four variations were observed of the DCIA. The deep circumflex iliac vein (DCIV) ran over (82.5%) or under (17.5%) the EIA. The superficial circumflex iliac vein (SCIV) was observed draining into the DCIV in some dissections. Three different variations of the superficial circumflex iliac artery (SCIA) were observed. The anatomical knowledge of these variations and their correlation to important surgical landmarks can help in harvesting the DCIA flap more safely and thus increasing the success rate while reducing donor site morbidity.

The response to loading of human articular cartilage as assessed by magnetic resonance imaging (MRI) remains to be defined in relation to histology and biomechanics. Therefore, an MRI-compatible whole-knee joint loading device for the functional in situ assessment of cartilage was developed and validated in this study. A formalin-fixed human knee was scanned by computed tomography in its native configuration and digitally processed to create femoral and tibial bone models. The bone models were covered by artificial femoral and tibial articular cartilage layers in their native configuration using cartilage-mimicking polyvinyl siloxane. A standardized defect of 8 mm diameter was created within the artificial cartilage layer at the central medial femoral condyle, into which native cartilage samples of similar dimensions were placed. After describing its design and specifications, the comprehensive validation of the device was performed using a hydraulic force gauge and digital electronic pressure-sensitive sensors. Displacement-controlled quasi-static uniaxial loading to 2.5 mm $$(\delta _{2.5})$$ and 5.0 mm $$(\delta _{5.0})$$ of the mobile tibia versus the immobile femur resulted in forces of $$141 \pm 8$$ N $$(\delta _{2.5})$$ and $$906 \pm 38$$ N $$(\delta _{5.0})$$ (on the entire joint) and local pressures of $$0.680 \pm 0.088$$ MPa $$(\delta _{2.5})$$ and $$1.050 \pm 0.100$$ MPa $$(\delta _{5.0})$$ (at the site of the cartilage sample). Upon confirming the MRI compatibility of the set-up, the response to loading of macroscopically intact human articular cartilage samples ( $$n=5$$ ) was assessed on a clinical 3.0-T MR imaging system using clinical standard proton-density turbo-spin echo sequences and T2-weighted multi-spin echo sequences. Serial imaging was performed at the unloaded state $$(\delta _{0})$$ and at consecutive loading positions (i.e. at $$\delta _{2.5}$$ and $$\delta _{5.0})$$ . Biomechanical unconfined compression testing (Young’s modulus) and histological assessment (Mankin score) served as the standards of reference. All samples were histologically intact (Mankin score, $$1.8 \pm 1.3$$ ) and biomechanically reasonably homogeneous (Young’s modulus, $$0.42 \pm 0.14$$ MPa). They could be visualized in their entirety by MRI and significant decreases in sample height [ $$\delta _{0}$$ : $$2.86 \pm 0.25$$ mm; $$\delta _{2.5}$$ : $$2.56 \pm 0.25$$ mm; $$\delta _{5.0}$$ : $$2.02 \pm 0.16$$ mm; $$p

Surgical reconstruction of the interosseous membrane may restore longitudinal forearm stability in Essex-Lopresti lesions. This study aimed to compare the longitudinal stability of the intact forearm with a single-bundle and a double-bundle reconstruction of the central band of the interosseous membrane using digital image correlation with a three-dimensional camera system. Single and cyclic axial loading of eight fresh-frozen forearm specimens was carried out in the intact state, after creation of an Essex-Lopresti lesion, after a single-bundle and after a double-bundle reconstruction of the central band using a TightRope® (Arthrex GmbH, Munich, Germany) construct. Instability significantly increased after creation of an Essex-Lopresti lesion. The stability of intact specimens was similar to both reconstruction techniques. The results of this study suggest that TightRope® reconstruction of the central band restores longitudinal forearm stability. However, the single-bundle technique may be less reliable than double-bundle reconstruction. Level of evidence: Basic Science Study

Background Although there are many studies discussing the etiological and pathological factors leading to both, acute and chronic tendon injuries, the pathophysiology of tendon injuries is still not clearly understood. Although most lesions are uncomplicated, treatment is long and unsatisfactory due to the poor vascularity of tendon tissue. Platelet mediator concentrate (PMC) contains many growth factors derived from platelets, which can promote wound healing. In this study we investigate the effects of PMC on tenocyte proliferation and differentiation in order to provide an experimental basis for tissue regeneration strategies and to develop new treatment concepts. Methods Using enzyme linked immunosorbent assay (ELISA) we were able to quantify the several growth factors and cytokines found in PMC. Tenocytes were isolated both from human and from mouse Achilles tendons and stimulated with PMC. CyQuant® and Cell Titer Blue® assays were carried out to analyze tendon growth and viability at different concentrations of PMC. Real time RT-PCR was used to analyze tenocyte gene expression with or without PMC treatment. Immunohistochemistry was carried out to detect the tenocyte-specific antibody tenomodulin (TNMD) and scleraxis (SCX). Results We were able to detect numerous mediators such as platelet derived growth factor BB (PDGF-BB), interleukin 6 (IL-6), vascular endothelial growth factor (VEGF), tumor necrosis factor (TNF-α), transforming growth factor beta 1 (TGF-ß1), and bone morphogenetic proteins 2, 4 and 7 (BMP-4, BMP-2, BMP-7) in PMC. It was possible to show a positive effect of PMC on human tendon cell growth and viability in a dose-dependent manner. Furthermore, PMC treatment led to induction of gene expression of scleraxis (SCX), type I collagen A 1 (Col1A1) and TNMD by tenocytes. Conclusions We suggest that the use of autologous PMC may be a suitable addition to conventional tendon therapy that is capable of increasing and optimizing tendon healing and reducing the risk of recurrence.

Different dissection studies as well as comparative studies about the anterolateral ligament of the knee (ALL) already exist and the structure’s topology and properties have been shown. However, most of the studies investigating the ligament were performed in embalmed knees, which is thought to change the structural integrity of ligaments and thus the topologic and dynamic measurements. Since the biomechanical function of the ALL is not fully understood until today and a correlation with the pivot shift phenomenon is yet speculative, further studies will have to clarify its definitive importance. Its function as a limiter of internal rotation and lateral meniscal extrusion leads to the assumption of a secondary knee stabilizer. Twenty paired fresh-frozen cadaveric knees of ten donors have been dissected in a layerwise fashion. After identification of the ALL, topologic measurements were undertaken using a digital caliper. The ALL could be identified as a tender, pearly structure in front of the anterolateral joint capsule in only 60% of the dissected knee joints. Only 20% of donors had a bilateral ALL while 80% had an ALL only in one side. Mean length, thickness and width as well as topographic measurements were comparable to other available studies investigating fresh-frozen cadavers. Anatomy and topography of the ALL seem to be highly variable, but consistent within certain borders. Prevalence has to be argued though as it strongly differs between studies. The impact of an ALL absence, even if only unilateral, needs to be investigated in clinical and imaging studies to finally clarify its importance.

Introduction Pectopexy, a laparoscopic method for prolapse surgery, showed promising results in recent literature. Further improving this approach by reducing surgical time may decrease complication rates and patient morbidity. Since laparoscopic suturing is a time consuming task, we propose a single suture /mesh ileo-pectineal ligament fixation as opposed to the commonly used continues approach. Methods Evaluation was performed on human non-embalmed, fresh cadaver pelves. A total of 33 trials was performed. Eight female pelves with an average age of 75, were used. This resulted in 16 available ligaments. Recorded parameters were ultimate load, displacement at failure and stiffness. Results The ultimate load for the mesh + simplified single “interrupted” suture (MIS) group was 35 (± 12) N and 48 (± 7) N for the mesh + continuous suture (MCS) group. There was no significant difference in the ultimate load between both groups (p> 0.05). This was also true for displacement at failure measured at 37 (± 12) mm and 36 (±5) mm respectively. There was also no significant difference in stiffness and failure modes. Conclusion Given the data above we must conclude that a continuous suture is not necessary in laparoscopic mesh / ileo-pectineal ligament fixation during pectopexy. Ultimate load and displacement at failure results clearly indicate that a single suture is not inferior to a continuous approach. The use of two single sutures may improve ligamental fixation. However, overall stability should not benefit since the surgical mesh remains the limiting factor.