Organization of descending neurons in the brain of the desert locust.

In most animals, multiple external and internal signals are integrated by the brain, transformed and, finally, transmitted as commands to motor centers. In insects, the central complex is a motor control center in the brain, involved in decision-making and goal-directed navigation. In desert locusts, it encodes celestial cues in a compass-like fashion indicating a role in sky-compass navigation. While several descending brain neurons (DBNs) including two neurons transmitting sky compass signals have been identified in the locust, a complete analysis of DBNs and their relationship to the central complex is still lacking. As a basis for further studies, we used Neurobiotin tracer injections into a neck connective to map the organization of DBNs in the brain. Cell counts revealed a maximum of 324 bilateral pairs of DBNs with somata distributed in 14 ipsilateral and nine contralateral groups. These neurons invaded most brain neuropils, especially the posterior slope, posterior and ventro-lateral protocerebrum, the antennal mechanosensory and motor center, but less densely the lateral accessory lobes that are targeted by central-complex outputs. No arborizations were found in the central complex and only few processes in the mushroom body, antennal lobe, lobula, medulla, and superior protocerebrum. Double label experiments provide evidence for the presence of GABA, dopamine, tyramine, but not serotonin, in small sets of DBNs. The data show that some DBNs may be targeted directly by central-complex outputs, but many others are likely only indirectly influenced by central-complex networks, in addition to input from multiple other brain areas.

Development of Open Backend Structures for Health Care Professionals to Improve Participation in App Developments: Pilot Usability Study of a Medical App.

BACKGROUND: Efficient digitization in medicine still is in its infancy but undeniably has great potential for current and future challenges in health care. Thus far, the rollout of medical apps has not resulted in widespread use of smartphones in the German health care sector-the reasons for this have not been clarified so far. Nevertheless, the lack of user involvement in the development process and content creation might contribute to low acceptance of these products. OBJECTIVE: This study aims to outline an approach to involve medical expertise without any coding knowledge for developing medical app content and functions. METHODS: An end user-operable backend was built. Its usability was evaluated using a usability evaluation test protocol. The results of the usability tests were evaluated by the app development team, and the usability test was repeated for optimizing backend usability. In total, 40 criteria to measure the ease of app usage were defined a priori. The usability test comprised 20 tasks that had to be fulfilled. Usability tasks were analyzed for completion, dropout, and test duration. Due to the COVID-19 pandemic, digital videoconferencing platforms (Zoom and QuickTime Player) were used to complete usability questionnaires. Finally, several backend-based apps for several specialties (infectiology, plastic and reconstructive surgery, and orthopedics) were developed by health care professionals as prototypes. RESULTS: Initial usability testing was conducted with 5 participants (4 men and 1 woman; mean age 39.2, SD 5.97 years). All of them could complete the assigned backend tasks with only a few workflow interruptions and some minor errors. After usability optimization, the workflow completion time decreased from 5.03 minutes to 3.50 minutes, indicating a time saving. The basic backend structure was clear to all test users and the handling was intuitive to learn. Some minor errors in the backend occurred during the test rounds. The apps developed using the aforementioned approach are in clinical use as a proof of concept. CONCLUSIONS: Backends offering operability for medical professionals might have great potential for app development in the mobile health sector. Sophisticated and time-saving usability are pivotal for the acceptance of medical software, as illustrated by the backend-based apps presented herein, which are in clinical use as a proof of concept. Basic interventions are essential and sufficient for adequate usability optimization. Practicable, well-structured software usability evaluation is possible based on the usability evaluation test protocol.

Proposal of a New Rating Concept for Digital Health Applications in Orthopedics and Traumatology.

BACKGROUND: Health-related mobile applications (apps) are rapidly increasing in number. There is an urgent need for assessment tools and algorithms that allow the usability and content criteria of these applications to be objectively assessed. The aim of this work was to establish and validate a concept for orthopedic societies to rate health apps to set a quality standard for their safe use. METHODS: An objective rating concept was created, consisting of nine quality criteria. A self-declaration sheet for app manufacturers was designed. Manufacturers completed the self-declaration, and the app was examined by independent internal reviewers. The pilot validation and analysis were performed on two independent health applications. An algorithm for orthopedic societies was created based on the experiences in this study flow. RESULTS: "Sprunggelenks-App" was approved by the reviewers with 45 (98%) fulfilled criteria and one (2%) unfulfilled criterion. "Therapie-App" was approved, with 28 (61%) met criteria, 6 (13%) unfulfilled criteria and 12 (26%) criteria that could not be assessed. The self-declaration completed by the app manufacturer is recommended, followed by a legal and technical rating performed by an external institution. When rated positive, the societies' internal review using independent raters can be performed. In case of a positive rating, a visual certification can be granted to the manufacturer for a certain time frame. CONCLUSION: An objective rating algorithm is proposed for the assessment of digital health applications. This can help societies to improve the quality assessment, quality assurance and patient safety of those apps. The proposed concept must be further validated for inter-rater consistency and reliability.

Metal Artefact Reduction Sequences (MARS) in Magnetic Resonance Imaging (MRI) after Total Hip Arthroplasty (THA) : A non-invasive approach for preoperative differentiation between periprosthetic joint infection (PJI) and aseptic complications?

BACKGROUND: In the past, radiographic imaging was of minor relevance in the diagnosis of periprosthetic joint infections (PJI). Since metal artefact reduction sequences (MARS) are available, magnetic resonance imaging (MRI) has become a promising diagnostic tool for the evaluation of hip arthroplasty implants. The purpose of the present study was to evaluate the efficacy of MARS-MRI in comparison to established diagnostic tools to distinguish between aseptic failure and PJI. METHODS: From July 2018 to September 2019, 33 patients classified as having an aseptic joint effusion were recruited into the study. The group included 22 women and 11 men with a mean age of 70.4 ± 13.7 (42-88) years. In the same period, 12 patients were classified as having a PJI. The group consisted of 9 women and 3 men with a mean age of 72.5 ± 10.6 (54-88) years. MARS-MRI was conducted using the optimized parameters at 1.5 T in a coronal and axial STIR (short-tau-inversion recovery), a non-fat-saturated T2 in coronal view and a non-fat-saturated T1 in transverse view in 45 patients with painful hip after total hip arthroplasty (THA). Normally distributed continuous data were shown as mean ± standard deviation (SD) and compared using student's t-test. Non-normally distributed continuous data were shown as mean and compared using the Mann-Whitney U test. RESULTS: Synovial layering and muscle edema were significant features of periprosthetic joint infection, with sensitivities of 100% and specifities of 63.0-75.0%. The combined specifity and sensitivity levels of synovial layering and muscular edema was 88.0% and 90.0%. Granulomatous synovitis was a significant feature for aseptic failure, with 90.0% sensitivity and 57.0% specifity. CONCLUSION: MARS-MRI is as suitable as standard diagnostic tools to distinguish between aseptic failure and PJI in patients with THA. Further studies with larger patient numbers have to prove whether MARS-MRI could be integral part of PJI diagnostic.

Acetylcholine Rechallenge: A First Step Toward Tailored Treatment in Patients With Coronary Artery Spasm.

OBJECTIVES: The present study aimed to assess the feasibility and clinical value of acetylcholine (ACh) rechallenge for the detection of coexisting epicardial and microvascular spasm and to determine the efficacy of nitroglycerin in these spasm endotypes. BACKGROUND: The coexistence of epicardial and microvascular spasm is difficult to identify; thus, its frequency is unknown. Nitroglycerin treatment is equally recommended for both epicardial and microvascular coronary spasm despite contradictory data. METHODS: In this multicenter study, 95 patients with coronary spasm were included to undergo ACh rechallenge, which consisted of repeated ACh provocation 3 minutes after intracoronary nitroglycerin administration using the same dose that previously induced spasm. RESULTS: In total, 95 patients (age 61 ± 12 years, 69% female) were included. Fifty-five patients (58%) had microvascular spasm, and 40 patients (42%) had epicardial spasm during initial ACh provocation. In 48% of patients with epicardial spasm, ACh rechallenge revealed coexisting nitroglycerin-persistent microvascular spasm. Nitroglycerin administration before ACh rechallenge prevented reinducibility of epicardial spasm in all patients with focal spasm and in 80% of patients with diffuse spasm. Microvascular spasm was prevented in only 20% by prior nitroglycerin administration but was attenuated in another 49% of patients. CONCLUSIONS: This study demonstrates a high frequency of epicardial spasm with coexisting nitroglycerin-persistent microvascular spasm. Intracoronary nitroglycerin was very effective in preventing reinducibility of epicardial spasm, whereas it prevented microvascular spasm in only 20% of patients. ACh rechallenge is a novel method that facilitates the detection of coexisting spasm endotypes and may pave the way towards tailored treatment of vasospastic angina.

Invasive Diagnosis of Coronary Functional Disorders Causing Angina Pectoris.

Coronary vasomotion disorders represent a frequent cause of angina and/or dyspnoea in patients with non-obstructed coronary arteries. The highly sophisticated interplay of vasodilatation and vasoconstriction can be assessed in an interventional diagnostic procedure. Established parameters characterising adequate vasodilatation are coronary blood flow at rest, and, after drug-induced vasodilation, coronary flow reserve, and microvascular resistance (hyperaemic microvascular resistance, index of microcirculatory resistance). An increased vasoconstrictive potential is diagnosed by provocation testing with acetylcholine or ergonovine. This enables a diagnosis of coronary epicardial and/or microvascular spasm. Ischaemia associated with microvascular spasm can be confirmed by ischaemic ECG changes and the measurement of lactate concentrations in the coronary sinus. Although interventional diagnostic procedures are helpful for determining the mechanism of the angina, which may be the key to successful medical treatment, they are still neither widely accepted nor applied in many medical centres. This article summarises currently well-established invasive methods for the diagnosis of coronary functional disorders causing angina pectoris.

Repurposing Riociguat for Treatment of Refractory Angina Resulting From Coronary Spasm.

Coronary spasm is a frequent cause of angina despite unobstructed coronary arteries, and symptom control with recommended drugs is limited. We report the case of a 77-year-old woman who had refractory angina despite conventional antianginal treatment. Repurposing riociguat, a soluble guanylate cyclase stimulator, resulted in improvement of symptoms and prevention of spasm. (Level of Difficulty: Intermediate.).

[Detection of ECG alterations typical for myocardial ischemia : New methods 2021]. / Erkennung ischämietypischer EKG-Veränderungen : Neue Methoden 2021.

BACKGROUND: The electrocardiogram (ECG) represents an essential diagnostic tool in cardiology and beyond. Classical ECG devices enable the registration of up to 12 leads, whereas modern ECG systems enable additional leads even with a reduced number of electrodes. Additionally, "smart" devices even enable patients to record an ECG at home. OBJECTIVE: Evaluation of a potential additional benefit of using various modern ECG systems for the detection of ECG alterations typical for myocardial ischemia. MATERIAL AND METHODS: Presentation of various signs of ischemia in the ECG according to the latest guidelines. Demonstration of modern ECG systems and their potential advantage in the detection of signs of ischemia in the ECG based on current study results. RESULTS: Modern ECG systems with vector-based electrocardiography can facilitate and optimize the detection of ischemic ECG alterations. Smart nonvector-based devices for patients are primarily useful for detection of arrhythmias and do not replace the 12-lead ECG for detection of ischemia, even though they can be useful for documentation of temporary ECG alterations also within the ST-segment. CONCLUSION: The ECG systems based on vector electrocardiography can improve the detection of ECG alterations typical for ischemia compared to the conventional 12-lead ECG.

Testing Acetylcholine Followed by Adenosine for Invasive Diagnosis of Coronary Vasomotor Disorders.

More than 50% of patients with signs and symptoms of myocardial ischemia undergoing coronary angiography have unobstructed coronary arteries. Coronary vasomotor disorders (impaired vasodilatation and/or enhanced vasoconstriction/spasm) represent important functional causes for such a clinical presentation. Although impaired vasodilatation may be assessed with non-invasive techniques such as positron emission tomography or cardiac magnetic resonance imaging, there is currently no reliable non-invasive technique for the diagnosis of coronary spasm available. Thus, invasive diagnostic procedures (IDP) have been developed for the diagnosis of coronary vasomotor disorders including spasm testing as well as assessment of coronary vasodilatation. The identification of the underlying type of disorder (so called endotype) allows the initiation of targeted pharmacological treatments. Despite the fact that such an approach is recommended by the current European Society of Cardiology guidelines for the management of chronic coronary syndromes based on the CorMicA study, comparability of results as well as multicenter trials are currently hampered by major differences in institutional protocols for coronary functional testing. This article describes a comprehensive IDP protocol including intracoronary acetylcholine provocation testing for diagnosis of epicardial/microvascular spasm, followed by Doppler wire-based assessment of coronary flow reserve (CFR) and hyperemic microvascular resistance (HMR) in search of coronary vasodilatory impairment.

Long-Term Radiographic Changes in Stemless Press-Fit Total Shoulder Arthroplasty.

INTRODUCTION: Stemmed humeral implants have represented the gold standard in total shoulder arthroplasty (TSA) for decades. Like many other joints, the latest trends in TSA designs aim at bone preservation. Current studies have demonstrated that native proximal humeral bone stresses are most closely mimicked by stemless implants. Nevertheless, there are concerns about the long-term performance of stemless designs. The aim of the present study was to evaluate the long-term radiographic changes at the proximal humerus in anatomical stemless press-fit TSA. MATERIALS AND METHODS: Between 2008 and 2010, 48 shoulders in 43 patients were resurfaced using an anatomic stemless shoulder prosthesis (TESS, Biomet). Thirty shoulders in twenty-five patients who were aged 65.7 ± 9.9 (34 to 82) years were available for clinical and radiographic review at a mean follow-up of 94.0 ± 8.9 (78 to 110) months. RESULTS: Radiographic changes of the proximal humerus due to stress shielding were found in 38.4% of the stemless TESS implants. Mild stress shielding accounted for 80% of the observed radiographic changes. Radiographs exhibited stable fixation of the stemless humeral press-fit implant at early and late follow-up. In contrast, radiolucent lines at the glenoid implant were found in 96.1% of the cases. Irrespective of the degree of radiographic changes, clinical scores (VAS, Quick-DASH, Constant score) significantly improved at follow-up. CONCLUSIONS: The anatomic stemless press-fit implant seems to be favorable in terms of implant-related stress shielding. Clinical outcome was not affected by radiographic changes, demonstrating an 8-year clinical performance that seems to be comparable to conventional stemmed TSA.

A small series of pole sport injuries.

Pole sport is a relatively new athletic sport that is gaining increasing popularity and for which national and international championships are held. It evolved from pole dance and harbours the risk of falls from heights of up to three metres. Currently, no studies on pole sport injuries are available. This is the first description of a small series of five pole sport injuries. A retrospective review of the case histories and radiological findings was performed, and in addition, a follow-up interview was carried out. All the patients were female and had a mean age of 27.2 years. Most injuries were located in the head, neck or spine. The use of proper training equipment like landing mats and grip aids could probably reduce accidents.

Smartphone and App Usage in Orthopedics and Trauma Surgery: Survey Study of Physicians Regarding Acceptance, Risks, and Future Prospects in Germany.

BACKGROUND: In the course of digitization, smartphones are affecting an increasing number of areas of users' lives, giving them almost ubiquitous access to the internet and other web applications. Mobile health (mHealth) has become an integral part of some areas of patient care. In contrast to other disciplines, routine integration of mobile devices in orthopedics and trauma surgery in Germany is still in its infancy. OBJECTIVE: This study aimed to investigate physicians' current state of opinion regarding acceptance, future prospects, and risks of medical apps in the field of orthopedics and trauma surgery in Germany. METHODS: A web-based survey among orthopedics and trauma surgeons in German university hospitals on the use of medical apps in everyday clinical practice was conducted between September 2018 and February 2019. The survey consisted of 13 open- and closed-ended or multiple-choice questions. A logistic regression analysis was performed to ascertain the effects of interindividual characteristics on the likelihood of participants' app and smartphone usage behavior. RESULTS: A total of 206 physicians participated in the survey. All of the participants (206/206, 100%) owned a smartphone, and 79.1% (159/201) used the device, while 64.7% (130/201) used apps regularly in everyday clinical practice. Medical apps were perceived as beneficial, given their substantial future promise, by 90.1% (181/201) of the participants. However, 62.5% (120/192) of the participants were not satisfied with the current supply of medical apps in app stores. Desired specifications for future apps were "intuitive usability" (167/201, 83.1%), "no advertising" (145/201, 72.1%), and "free apps" (92/201, 45.8%). The attributes "transparent app development and app sponsoring" (75/201, 37.3%) and the existence of an "easy-to-understand privacy statement" (50/201, 24.9%) were of minor relevance. The majority of the participants (162/194, 83.5%) considered that future apps in the field of "medical research" would provide the greatest benefit. The greatest predicted risks were "data misuse" (147/189, 77.8%), "usage of untrustworthy apps" (135/189, 71.4%), and "alienation from patients" (51/189, 27.0%). Increasing age was significantly associated with a reduction in the likelihood of regular smartphone (odds ratio [OR] 0.91, 95% CI 0.86-0.97; P=.002) and app (OR 0.90, 95% CI 0.85-0.96; P=.001) usage, while the medical profession grade had no significant impact on the usage behavior. CONCLUSIONS: The study demonstrates that young German doctors in orthopedics and trauma surgery already use smartphones and apps in everyday clinical practice. Medical apps are considered to play an important role in the future. However, a significant discrepancy exists between the supply and demand of mHealth applications, which creates a legal and ethical vacuum with regard to data protection.

First ray alignment in Lapidus arthrodesis - Effect on plantar pressure distribution and the occurrence of metatarsalgia.

BACKGROUND: Lapidus arthrodesis is an established treatment option for severe hallux valgus deformity especially in patients suffering from instability of the first tarsometatarsal joint. Surgery related metatarsalgia is known to be associated with persistent elevation of the first ray after realignment surgery. Nevertheless, detailed information on ideal positioning of the first ray in Lapidus surgery is missing so far. This study was designed to determine any correlations between radiographic and pedobarographic outcome following the Lapidus procedure with regard to clinical outcome and the occurrence of metatarsalgia. METHODS: Thirty feet (28 patients) after Lapidus surgery were available for follow-up at 42.5±21.0 months. All subjects had radiographic and pedobarographic evaluation of the operated foot and patient satisfaction was recorded using questionnaires. RESULTS: Metatarsalgia was associated with a poorer outcome in FADI and AOFAS scores (p<0.005). A lateral shift of plantar pressure distribution to the third metatarsal head in these cases could be observed. Although Lapidus surgery resulted in significant shortening of the first metatarsal, no correlation to the occurrence of metatarsalgia was detectable. Likewise, axial plane malalignment showed no influence, whereas elevation of the first ray was highly correlated to surgery related metatarsalgia (p=0.007). Subjects suffering from metatarsalgia had a higher BMI (body mass index), but its effect on metatarsalgia turned out not to be significant (p=0.090). CONCLUSION: In Lapidus surgery realignment of the first metatarsal in the sagittal plane seems to be decisive for good clinical outcome. Failing to plantarflex the arthrodesis resulted in a lateral shift of plantar loading with overload of the lesser metatarsals and the occurrence of metatarsalgia.

Correction: Analysis of Secure Apps for Daily Clinical Use by German Orthopedic Surgeons: Searching for the "Needle in a Haystack".

[This corrects the article DOI: 10.2196/17085.].

Analysis of Secure Apps for Daily Clinical Use by German Orthopedic Surgeons: Searching for the "Needle in a Haystack".

BACKGROUND: It is undeniable that appropriate smartphone apps offer enormous opportunities for dealing with future challenges in orthopedic surgery and public health, in general. However, it is still unclear how the apps currently available in the two major app stores can be used in daily clinical routine by German orthopedic surgeons. OBJECTIVE: This study aimed to gain evidence regarding the quantity and quality of apps available in the two major app stores and their suitability for use by orthopedic surgeons in Germany. METHODS: We conducted a systematic, keyword-based app store screening to obtain evidence concerning the quantity and quality of commercially available apps. Apps that met the inclusion criteria were evaluated using the app synopsis-checklist for users and the German Mobile App Rating Scale for secure use, trustworthiness, and quality. RESULTS: The investigation revealed serious shortcomings regarding legal and medical aspects. Furthermore, most apps turned out to be useless and unsuitable for the clinical field of application (4242/4249, 99.84%). Finally, 7 trustworthy and high-quality apps (7/4249, 0.16%) offering secure usage in the daily clinical routine of orthopedists were identified. These apps mainly focused on education (5/7). None of them were CE (Conformité Européenne) certified. Moreover, there are no studies providing evidence that these apps have any positive use whatsoever. CONCLUSIONS: The data obtained in our study suggest that the number of trustworthy and high-quality apps on offer is extremely low. Nowadays, finding appropriate apps in the fast-moving, complex, dynamic, and rudimentarily controlled app stores is most challenging. Promising approaches, for example, systematic app store screenings, app-rating developments, reviews or app libraries, and the creation of consistent standards have been established. However, further efforts are necessary to ensure that these innovative mobile health apps not only provide the correct information but are also safe to use in daily clinical practice.

A Possible Mobile Health Solution in Orthopedics and Trauma Surgery: Development Protocol and User Evaluation of the Ankle Joint App.

BACKGROUND: Ankle sprains are one of the most frequent sports injuries. With respect to the high prevalence of ankle ligament injuries and patients' young age, optimizing treatment and rehabilitation is mandatory to prevent future complications such as chronic ankle instability or osteoarthritis. OBJECTIVE: In modern times, an increasing amount of smartphone usage in patient care is evident. Studies investigating mobile health (mHealth)-based rehabilitation programs after ankle sprains are rare. The aim of this study was to expose any issues present in the development process of a medical app as well as associated risks and chances. METHODS: The development process of the Ankle Joint App was defined in chronological order using a protocol. The app's quality was evaluated using the (user) German Mobile App Rating Scale (MARS-G) by voluntary foot and ankle surgeons (n=20) and voluntary athletes (n=20). RESULTS: A multidisciplinary development team built a hybrid app with a corresponding backend structure. The app's content provides actual medical literature, training videos, and a log function. Excellent interrater reliability (interrater reliability=0.92; 95% CI 0.86-0.96) was obtained. The mean overall score for the Ankle Joint App was 4.4 (SD 0.5). The mean subjective quality scores were 3.6 (surgeons: SD 0.7) and 3.8 (athletes: SD 0.5). Behavioral change had mean scores of 4.1 (surgeons: SD 0.7) and 4.3 (athletes: SD 0.7). The medical gain value, rated by the surgeons only, was 3.9 (SD 0.6). CONCLUSIONS: The data obtained demonstrate that mHealth-based rehabilitation programs might be a useful tool for patient education and collection of personal data. The achieved (user) MARS-G scores support a high quality of the tested app. Medical app development with an a priori defined target group and a precisely intended purpose, in a multidisciplinary team, is highly promising. Follow-up studies are required to obtain funded evidence for the ankle joints app's effects on economical and medical aspects in comparison with established nondigital therapy paths.

7-T clinical MRI of the shoulder in patients with suspected lesions of the rotator cuff.

BACKGROUND: To evaluate feasibility and diagnostic performance of clinical 7-T magnetic resonance imaging (MRI) of the shoulder. METHODS: Eight patients with suspected lesions of the rotator cuff underwent 7-T MRI before arthroscopy. Image quality was scored for artifacts, B1+ inhomogeneities, and assessability of anatomical structures. A structured radiological report was compared to arthroscopy. In four patients, a visual comparison with pre-existing 1.5-T examinations was performed. RESULTS: Regarding image quality, the majority of the sequences reached values above the middle of each scoring scale. Fat-saturated proton density sequences showed least artifacts and best structure assessability. The most homogenous B1+ field was reached with gradient-echo sequences. Arthroscopy did not confirm tendinopathy/partial tear of supraspinatus in 5/8 patients, of subscapularis in 5/6, and of infraspinatus in one patient; only a partial lesion of the subscapularis tendon was missed. Pathologic findings of long bicipital tendon, acromioclavicular joint, glenohumeral cartilage, labrum, and subacromial subdeltoideal bursa were mainly confirmed; exceptions were one lesion of the long bicipital tendon, one subacromial bursitis, and one superior glenoid labrum anterior-to-posterior lesion, missed on 7-T MRI. Evaluating all structures together, sensitivity was 86%, and specificity 74%. A better contrast and higher image resolution was noted in comparison to previous 1.5-T examinations. CONCLUSIONS: 7-T MRI of the shoulder with diagnostic image quality is feasible. Overrating of tendon signal alterations was the main limitation. Although the diagnostic performance did not reach the current results of 3-T MRI, our study marks the way to implement clinical 7-T MRI of the shoulder.

Sphingosine is able to prevent and eliminate Staphylococcus epidermidis biofilm formation on different orthopedic implant materials in vitro.

Periprosthetic infection (PPI) is a devastating complication in joint replacement surgery. On the background of an aging population, the number of joint replacements and associated complications is expected to increase. The capability for biofilm formation and the increasing resistance of different microbes to antibiotics have complicated the treatment of PPI, requiring the need for the development of alternative treatment options. The bactericidal effect of the naturally occurring amino alcohol sphingosine has already been reported. In our study, we demonstrate the antimicrobial efficacy of sphingosine on three different strains of biofilm producing Staphylococcus epidermidis, representing one of the most frequent microbes involved in PPI. In an in vitro analysis, sphingosine's capability for prevention and treatment of biofilm-contamination on different common orthopedic implant surfaces was tested. Coating titanium implant samples with sphingosine not only prevented implant contamination but also revealed a significant reduction of biofilm formation on the implant surfaces by 99.942%. When testing the antimicrobial efficacy of sphingosine on sessile biofilm-grown Staphylococcus epidermidis, sphingosine solution was capable to eliminate 99.999% of the bacteria on the different implant surfaces, i.e., titanium, steel, and polymethylmethacrylate. This study provides evidence on the antimicrobial efficacy of sphingosine for both planktonic and sessile biofilm-grown Staphylococcus epidermidis on contaminated orthopedic implants. Sphingosine may provide an effective and cheap treatment option for prevention and reduction of infections in joint replacement surgery. KEY MESSAGES: • Here we established a novel technology for prevention of implant colonization by sphingosine-coating of orthopedic implant materials. • Sphingosine-coating of orthopedic implants prevented bacterial colonization and significantly reduced biofilm formation on implant surfaces by 99.942%. • Moreover, sphingosine solution was capable to eliminate 99.999% of sessile biofilm-grown Staphylococcus epidermidis on different orthopedic implant surfaces.

Sphingosine-coating of plastic surfaces prevents ventilator-associated pneumonia.

Ventilator-associated pneumonia (VAP) is a major cause of morbidity and mortality in critically ill patients. Here, we employed the broad antibacterial effects of sphingosine to prevent VAP by developing a novel method of coating surfaces of endotracheal tubes with sphingosine and sphingosine analogs. Sphingosine and phytosphingosine coatings of endotracheal tubes prevent adherence and mediate killing of Pseudomonas aeruginosa, Acinetobacter baumannii, and Staphylococcus aureus, even in biofilms. Most importantly, sphingosine-coating of endotracheal tubes also prevented P. aeruginosa and S. aureus pneumonia in vivo. Coating of the tubes with sphingosine was stable, without obvious side effects on tracheal epithelial cells and did not induce inflammation. In summary, we describe a novel method to coat plastic surfaces and provide evidence for the application of sphingosine and phytosphingosine as novel antimicrobial coatings to prevent bacterial adherence and induce killing of pathogens on the surface of endotracheal tubes with potential to prevent biofilm formation and VAP. KEY MESSAGES: Novel dip-coating method to coat plastic surfaces with lipids. Sphingosine and phytosphingosine as novel antimicrobial coatings on plastic surface. Sphingosine coatings of endotracheal tubes prevent bacterial adherence and biofilms. Sphingosine coatings of endotracheal tubes induce killing of pathogens. Sphingosine coatings of endotracheal tubes ventilator-associated pneumonia.

Long-term results of the reverse Total Evolutive Shoulder System (TESS).

INTRODUCTION: Latest trends in shoulder replacement aim at bone stock preservation. Long-term results of stemless anatomical total shoulder implants compare favourably with stemmed designs in terms of function and survivorship. The Total Evolutive Shoulder System (TESS) has been one of the first designs offering a stemless implant not only for anatomical but also for reverse total shoulder arthroplasty with optional short stem attachment in cases with poor bone quality. The aim of the present study was to evaluate long-term results of the reverse Total Evolutive Shoulder System (TESS). MATERIALS AND METHODS: Between 2006 and 2009, 49 shoulders in 47 patients were replaced using the Biomet reverse Total Evolutive Shoulder System (TESS). 29 shoulders in 27 patients who were aged 72.4 ± 6.7 (53-88) years were available for review at a mean follow-up of 101.6 ± 24.6 (75-142) months. RESULTS: The implant survival rate was 93.1% at 101 months (8.4 years). The overall revision rate of the TESS implant was 17.2%. No implant associated complications to the reverse corolla implant could be observed. All reverse corolla implants showed solid fixation at follow-up. Scapular notching was found in 72.3% of the shoulders. Clinical scores significantly improved at long-term follow-up (VAS from 7.5 ± 1.2 to 1.4 ± 1.5, p < 0.001; quick-DASH from 70.9 ± 12.0 to 28.9 ± 22.9, p < 0.001 and Constant score from 13.0 ± 3.7 to 60.5 ± 16.8, p < 0.001). CONCLUSIONS: In terms of clinical scores, radiographic loosening, complication rates and implant survivorship the reverse Total Evolutive Shoulder System provides results comparable to those of conventional stemmed reverse shoulder arthroplasty.