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Background: Treatment of failed total ankle arthroplasty (TAA) is challenging. Limited literature is available on options and outcomes of revision arthroplasty despite failure rates ranging from 10% to 23% within 10 years after primary TAA. This study reports the clinical and radiographic outcomes of revision TAA using a fixed-bearing, intramedullary-referencing implant. Methods: A retrospective review was performed of 18 consecutive revision TAA cases between 2008-2015 using an intramedullary-referencing, fixed-bearing, 2-component total ankle system. Demographic and radiographic data were collected preoperatively, immediately postoperatively, and at the most recent follow-up. Functional outcome data were collected immediately postoperatively and at mean follow-up 47.5 months. Results: Eighteen patients underwent revision TAA, with 77.8% (14/18) implant survival. Index revision was performed most commonly for aseptic talar subsidence (55.6%) or implant loosening (tibia, 29.4%; talus, 58.9%). Following revision, 22.2% (4/18) patients required reoperation at a mean 57.3 (39-86) months. Osteolysis of the tibia, talus, and fibula was present preoperatively in 66.7% (12/18), 38.9% (7/18), and 38.9% (7/18) of patients, respectively, with progression of osteolysis in 27.8% (5/18), 11.1% (2/18) and 11.1% (2/18) of patients, respectively. Subsidence of the tibial and talar revision components was observed in 38.9% (7/18) and 55.6% (10/18) of patients, respectively. The median American Orthopaedic Foot & Ankle Society (AOFAS) score was 74.5 (26-100) and Foot Function Index (FFI) score 10.2 (0-50.4). Conclusion: Early results of intramedullary-referencing revision TAA demonstrated good patient-reported outcomes with maintenance of radiographic parameters at mean follow-up of 47.5 months. Aseptic talar subsidence or loosening were the main postoperative causes of reoperation. Revision arthroplasty utilizing an intramedullary-referencing implant was a viable option for the failed TAA. Level of Evidence: Level IV, case series.

Stress fractures of the ankle, relatively rare in the general population, are markedly more common in athletes, especially running and jumping athletes. Athletes who participate in extreme training are at high risk, particularly when compounded with other risk factors such as poor mechanics, footwear, and/or acute changes in regimen. Females, especially elite-level athletes, may be at increased risk to due to the female athlete triad of amenorrhea, inadequate caloric intake, and decreased bone density. Athletes classically present with pain exacerbated by the activity, swelling, and focal tenderness. Diagnosis is often delayed, as initial radiographs are often negative. However, advanced imaging with magnetic resonance imaging (MRI) reveals typical patterns of edema, and, in later stages, fracture lines. Concern for endocrine and/or metabolic abnormalities should prompt further workup, particularly if there is concern for the female athlete triad. Stress fractures at the ankle may be low-risk or high-risk based on their potential for healing. In both scenarios, stress fractures of the fibula, distal tibia, medial malleolus, and talus may be treated initially with rest from activity, and possibly immobilization and/or limited weight-bearing in specific cases. Certain factors may indicate operative management, including lack of response to nonoperative management, progression to sclerosis and/or cystic change at the stress fracture site, or potentially in elite athletes with time-sensitive return-to-play needs and/or high risk of progression. In the future, there may be a role for novel modalities, including teriparatide, extracorporeal shock wave therapy (ESWT), bone stimulators, and orthobiologic agents, but further research is needed.

Diagnostic leukapheresis (DLA) enables to sample larger blood volumes and increases the detection of circulating tumor cells (CTC) significantly. Nevertheless, the high excess of white blood cells (WBC) of DLA products remains a major challenge for further downstream CTC enrichment and detection. To address this problem, we tested the performance of two label-free CTC technologies for processing DLA products. For the testing purposes, we established ficollized buffy coats (BC) with a WBC composition similar to patient-derived DLA products. The mimicking-DLA samples (with up to 400 × 106 WBCs) were spiked with three different tumor cell lines and processed with two versions of a spiral microfluidic chip for label-free CTC enrichment: the commercially available ClearCell FR1 biochip and a customized DLA biochip based on a similar enrichment principle, but designed for higher throughput of cells. While the samples processed with FR1 chip displayed with increasing cell load significantly higher WBC backgrounds and decreasing cell recovery, the recovery rates of the customized DLA chip were stable, even if challenged with up to 400 × 106 WBCs (corresponding to around 120 mL peripheral blood or 10% of a DLA product). These results indicate that the further up-scalable DLA biochip has potential to process complete DLA products from 2.5 L of peripheral blood in an affordable way to enable high-volume CTC-based liquid biopsies.

Category: Other Introduction/Purpose: Cases of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus (COVID-19) first emerged in Wuhan, China, in December 2019. Since then, the virus has spread globally at a rapid pace. The first case in New York City was reported on March 1, 2020, and the World Health Organization (WHO) declared a pandemic on March 11, 2020. New York City rapidly became the epicenter of the pandemic, with hospitals across the city making a number of changes to accommodate the influx of COVID-19 patients. Here, we describe our experience in adapting to the COVID-19 pandemic as a department consisting of 10 foot and ankle fellowship-trained surgeons with up to 28 years of individual experience in an academic orthopedic hospital. Methods: Information was obtained from direct interviews with surgeons in the Foot and Ankle Service and from our institution’s intranet. Additional information was obtained by viewing twice-weekly livestreams from March 27th, 2020 to May 1st, 2020 held by the Surgeon-In-Chief, which detailed hospital-wide policies and initiatives being implemented in the wake of the COVID-19 pandemic. Results: On March 17, 2020, all elective surgeries were suspended at our institution, and a list of essential procedures was established. In-person clinical visits were limited to new patients being evaluated for essential procedures and first postoperative visits for returning patients, with all patients receiving pre-visit and on-site screening for COVID-19. All other new patient and follow-up appointments were conducted via telehealth visits. Much of our main hospital was repurposed to accept transfers of both COVID-negative and COVID-positive patients. A postanesthesia care unit and a floor of 9 operating rooms were repurposed as negative-pressure rooms for the care of critical COVID-positive patients on ventilators. An Orthopedic Triage Center (OTC) was established to relieve the patient load in the emergency departments of other hospitals in the city. Conclusion: By changing the way we delivered foot and ankle care and repurposing the roles of our employees and our institution, we have adapted strategies to continue delivering care to our patients. As we transition toward a ‘new normal,’ our goals are to gradually progress toward normal operations while keeping our patients and employees safe. With these gradual steps, we hope to emerge from this pandemic stronger and ready to adapt to the ever-changing needs of our community.

Surgical management of osteochondral lesions of the talus without an osteotomy depends on the size, location, and chronicity of the lesion. Bone marrow stimulation techniques, such as microfracture, can be performed arthroscopically and have consistently good outcomes in lesions less than 1 cm in diameter. For lesions not amenable to bone marrow stimulation, one-stage techniques, such as allograft cartilage extracellular matrix and allograft juvenile hyaline cartilage, may be used. Arthroscopy may be used in many cases to address these lesions; however, an arthrotomy may be required to use osteochondral autograft and allograft transplantation techniques.

To improve access to high-quality HIV care in underserved regions of Western Washington (WA) State, we collaborated with the WA State Department of Health (DOH) and community partners to launch four satellite HIV clinics. Here, we describe this innovative clinical care model, present an estimate of costs, and evaluate patient care outcomes, including virologic suppression rates. To accomplish this, we assessed virologic suppression rates 12 months before and 12 months after the satellite clinics opened, comparing people living with HIV (PLWH) who enrolled in the satellite clinics versus all PLWH in the same regions who did not. We also determined virologic suppression rates in 2015 comparing satellite clinic versus non-satellite clinic patients and compared care quality indicators between the satellite clinics and the parent academic clinic. Results demonstrate that the change in virologic suppression rate 12 months before to 12 months after the satellite clinics opened was higher for patients who enrolled in the satellite clinics compared to all those in the same region who did not (18% versus 6%, p < 0.001). Virologic suppression in 2015 was significantly higher for satellite clinic than non-satellite clinic patients at three of four sites. Care quality indicators were met at a high level at the satellite clinics, comparable to the parent academic clinic. Overall, through community partnerships and WA DOH support, the satellite clinic program increased access to best practice HIV care and improved virologic suppression rates in difficult-to-reach areas. This model could be expanded to other regions with inadequate access to HIV practitioners, though financial support is necessary.

Während der Herstellung durch Verbundschmieden beeinflussen die in den Werkstoffen enthaltenden Legierungselemente maßgeblich die Verbundqualität und führen zu teilweise hohen Abweichungen. Dieser Umstand kann durch die pulvermetallurgische Herstellung von Halbzeugen mit definierter Werkstoffzusammensetzung vermieden werden. In diesem Fachbeitrag werden die Verfahrenskombination sowie die Herausforderungen entlang der Prozesskette und entsprechende Lösungsansätze vorgestellt. During compound forging, the alloying elements contained in the materials significantly influence the quality of the compound and in some cases lead to high deviations. This can be remedied by the powder-metallurgical production of semi-finished products with a defined material composition. This article presents the combination of processes and the challenges along the process chain as well as corresponding approaches to solutions.

Im Fokus dieses Beitrages steht die numerische Prozessauslegung zur Herstellung einer hybriden Lagerbuchse aus Aluminium und Stahl. Aufgrund der unterschiedlichen thermo-physikalischen Eigenschaften der Werkstoffe ergeben sich Herausforderungen bei der Umformung der hybriden Halbzeuge. Im Beitrag werden geeignete Umformtemperaturbereiche definiert, bei denen die beteiligten Verbundpartner vergleichbare Fließeigenschaften aufweisen, sowie die numerische Prozessauslegung vorgestellt. This paper focuses on the numerical process design of a hybrid bearing bushing made of aluminium and steel using tailored forming. The different thermo-physical properties of the materials bring about challenges in the forming of the hybrid semi-finished products. Suitable forming temperature ranges are defined in which the two materials have comparable flow properties, and the numerical process design is presented.

Purpose To analyze referral indications, imaging findings and diagnoses in breast sonography in a division of pediatric radiology. Materials and Methods Breast ultrasound examinations of 270 patients were analyzed for referral reasons, imaging findings and final diagnoses (152 females, 118 males). The mean age of the patients was 8.8 years (range, 6 days–18 years). Each breast was examined systematically in two orthogonal probe orientations. Pathological findings were documented on two orthogonal imaging planes. Color Doppler ultrasonography was used additionally. Images and clinical data were reviewed in all cases. Results The most frequent referral reasons in female patients were breast enlargement (104 patients), palpable mass (24 patients) and mastodynia (23 patients). The most frequent diagnoses were normal gland tissue (101 patients), cysts (9 patients), augmented adipose tissue (7 patients) and hemangiomas (7 patients). The most frequent referral reasons in male patients were breast enlargement (106 patients), palpable mass (13 patients) and mastodynia (9 patients). The most frequent diagnoses were gland tissue (79 patients), augmented adipose tissue (24 patients) and cysts (10 patients). Only 2 malignant masses were diagnosed: A Burkitt lymphoma and a relapsed ALL. Conclusion Fear of breast cancer and permanent damage to the breast leads to low-threshold medical consultations and referrals. Sensitive handling is required especially in adolescent patients. Most disorders arise due to the variability of breast development. Ultrasound serves as a means to exclude significant diseases of the breast.

BMD_GV_ml1_ml2.docx. Results BMD and GV. Measured bone mineral content (DEXA) and gray scale values (X-ray) for the regions of interest 1–5 (ROI1 – ROI5) in ml1 and ml2: mean value (M) ± standard deviation (SD), coefficient of variation [CV]. (DOCX 25 kb)

Meniscal injury is a common cause for presentation to the emergency department or primary care physician's office. Meniscal injuries can be the result of a forceful, twisting event in a young athlete's knee or it can insidiously present in the older patient. Many patients with meniscal pathology appropriately undergo conservative management with a primary care physician while some may need referral to an orthopedist for operative intervention. Arthroscopic surgery to address the menisci is the most frequently performed procedure on the knee and one of the most regularly performed surgeries in orthopedic surgery.1 The purpose of this paper is to help elucidate the diagnosis and management of meniscal pathology resulting in knee pain. [Full article available at http://rimed.org/rimedicaljournal-2016-10.asp].

Purpose To examine the anatomy of the lateral ankle after arthroscopic repair of the lateral ligament complex (anterior talofibular ligament [ATFL] and calcaneofibular ligament [CFL]) with regard to structures at risk. Methods Ten lower extremity cadaveric specimens were obtained and were screened for gross anatomic defects and pre-existing ankle laxity. The ATFL and CFL were sectioned from the fibula by an open technique. Standard anterolateral and anteromedial arthroscopy portals were made. An additional portal was created 2 cm distal to the anterolateral portal. The articular surface of the fibula was identified, and the ATFL and CFL were freed from the superficial and deeper tissues. Suture anchors were placed in the fibula at the ATFL and CFL origins and were used to repair the origin of the lateral collateral structures. The distance from the suture knot to several local anatomic structures was measured. Measurements were taken by 2 separate observers, and the results were averaged. Results Several anatomic structures lie in close proximity to the ATFL and CFL sutures. The ATFL sutures entrapped 9 of 55 structures, and no anatomic structures were inadvertently entrapped by the CFL sutures. The proximity of the peroneus tertius and the extensor tendons to the ATFL makes them at highest risk of entrapment, but the proximity of the intermediate branch of the superficial peroneal nerve (when present) is a risk with significant morbidity. Conclusions Our results indicate that the peroneus tertius and extensor tendons have the highest risk for entrapment and show the smallest mean distances from the anchor knot to the identified structure. Careful attention to these structures, as well as the superficial peroneal nerve, is mandatory to prevent entrapment of tendons and nerves when one is attempting arthroscopic lateral ankle ligament reconstruction. Clinical Relevance Defining the anatomic location and proximity of the intervening structures adjacent to the lateral ligament complex of the ankle may help clarify the anatomic safe zone through which arthroscopic repair of the lateral ligament complex can be safely performed.

Context: Stress fractures are common injuries in athletes, often difficult to diagnose. A stress fracture is a fatigue-induced fracture of bone caused by repeated applications of stress over time. Evidence Acquisition: PubMed articles published from 1974 to January 2012. Results: Intrinsic and extrinsic factors may predict the risk of stress fractures in athletes, including bone health, training, nutrition, and biomechanical factors. Based on their location, stress fractures may be categorized as low- or high-risk, depending on the likelihood of the injury developing into a complete fracture. Treatment for these injuries varies substantially and must account for the risk level of the fractured bone, the stage of fracture development, and the needs of the patient. High-risk fractures include the anterior tibia, lateral femoral neck, patella, medial malleolus, and femoral head. Low-risk fractures include the posteromedial tibia, fibula, medial femoral shaft, and pelvis. Magnetic resonance is the imaging test of choice for diagnosis. Conclusions: These injuries can lead to substantial lost time from participation. Treatment will vary by fracture location, but most stress fractures will heal with rest and modified weightbearing. Some may require more aggressive intervention, such as prolonged nonweightbearing movement or surgery. Contributing factors should also be addressed prior to return to sports.

Cardiac rhythms arise from electrical activity generated by precisely timed opening and closing of ion channels in individual cardiac myocytes. These impulses spread throughout the cardiac muscle to manifest as electrical waves in the whole heart. Regularity of electrical waves is critically important since they signal the heart muscle to contract, driving the primary function of the heart to act as a pump and deliver blood to the brain and vital organs. When electrical activity goes awry during a cardiac arrhythmia, the pump does not function, the brain does not receive oxygenated blood, and death ensues. For more than 50 years, mathematically based models of cardiac electrical activity have been used to improve understanding of basic mechanisms of normal and abnormal cardiac electrical function. Computer-based modeling approaches to understand cardiac activity are uniquely helpful because they allow for distillation of complex emergent behaviors into the key contributing components underlying them. Here we review the latest advances and novel concepts in the field as they relate to understanding the complex interplay between electrical, mechanical, structural, and genetic mechanisms during arrhythmia development at the level of ion channels, cells, and tissues. We also discuss the latest computational approaches to guiding arrhythmia therapy.

Malnutrition in orthopaedic patients, a condition that is overlooked and understudied, has substantial effects on outcomes1-6. Underweight and malnourished elderly patients are at risk of experiencing reduced well-being and autonomy as well as increased mortality as compared with their counterparts of normal weight7. Malnutrition may be simply defined as an imbalance of energy, protein, and nutrients leading to functional and compositional adverse effects on the body8,9. By this definition, as much as 15% of ambulatory and 65% of hospitalized patients are malnourished10. Without adequate nutrition, orthopaedic patients are more susceptible to infections, slower healing rates, and sarcopenia (reduced lean body mass and muscle function)8. Stratifying malnutrition on the basis of etiology (e.g., “starvation-related,” “chronic disease-related,” and “acute injury or illness-related”) facilitates the formation of a more clinically relevant definition11. In starvation, the primary problem is reduced intake, possibly due to socioeconomic factors or secondary to anorexia6. With chronic disease and acute injury, increases in resting energy expenditure and protein requirements due to the inflammatory response contribute to malnourishment7. The new etiology-based approach to the diagnosis of malnutrition …

The gluon momentum density xg ( x , Q 2 ) of the proton was extracted at Q 2 = 20 GeV 2 for small values of x between 4 × 10 −4 and 10 −2 from the scaling violations of the proton structure function F 2 measured recently by ZEUS in deep inelastic neutral current ep scattering at HERA. The extraction was performed in two ways. Firstly, using a global NLO fit to the ZEUS data on F 2 at low x constrained by measurementsfrom NMC at larger x ; and secondly using published approximate methods for the solution of the GLAP QCD evolution equations. Consistent results are obtained. A substantial increase of the gluon density is found at small x in comparison with the NMC result obtained at larger values of x .

Simvastatin is a common medication prescribed for hypercholesterolemia that accelerates local bone formation. It is unclear whether simvastatin can accelerate healing at the tendon-bone interface after rotator cuff repair. This study was conducted to investigate whether local and systemic administration of simvastatin increased tendon-bone healing of the rotator cuff as detected by maximum load to failure in a controlled animal-based model. Supraspinatus tendon repair was performed on 120 Sprague-Dawley rats. Sixty rats had a polylactic acid membrane overlying the repair site. Of these, 30 contained simvastatin and 30 did not contain medication. Sixty rats underwent repair without a polylactic acid membrane. Of these, 30 received oral simvastatin (25 mg/kg/d) and 30 received a regular diet. At 4 weeks, 5 rats from each group were killed for histologic analysis. At 8 weeks, 5 rats from each group were killed for histologic analysis and the remaining 20 rats were killed for biomechanical analysis. One rat that received oral simvastatin died of muscle necrosis. Average maximum load to failure was 35.2±6.2 N for those receiving oral simvastatin, 36.8±9.0 N for oral control subjects, 39.5±12.8 N for those receiving local simvastatin, and 39.1±9.3 N for control subjects with a polylactic acid membrane. No statistically significant differences were found between any of the 4 groups ( P >.05). Qualitative histologic findings showed that all groups showed increased collagen formation and organization at 8 weeks compared with 4 weeks, with no differences between the 4 groups at each time point. The use of systemic and local simvastatin offered no benefit over control groups. [ Orthopedics. 2017; 40(2):e288–e292.]

Lateral epicondylitis, or tennis elbow, is the most common cause of elbow pain. This degenerative condition can manifest as an acute process lasting < 3 months or a chronic process often refractory to treatment. Symptom resolution occurs in 70% to 80% of patients within the first year. A "watch-and-wait" approach can be an appropriate treatment option, although physical therapy has been shown to be an effective first-line therapy. Corticosteroids, while providing relief of pain in the acute setting, may be detrimental to recovery in the long term. Platelet-rich plasma injections, although recently well publicized, have not been proven by well-controlled clinical trials to be effective therapy. For patients with symptoms refractory to conservative management, surgical intervention has shown to be a successful treatment modality.

Background: The outcome of rotator cuff repair correlates with tendon healing. Early studies of arthroscopic rotator cuff repair demonstrate lower healing rates than traditional open techniques. Transosseous-equivalent repair techniques (suture bridge) were developed to improve the initial fixation strength. Purpose: To compare the initial in vitro tensile fixation strength of a transosseous-equivalent suture bridge (TOE-SB) rotator cuff repair construct to a traditional transosseous (TO) suture construct. Study Design: Controlled laboratory study. Methods: Identical simulated rotator cuff tears were created on 8 matched pairs of humeri. Each matched pair underwent repair with 4 sutures using either the TOE-SB or TO technique. Initial fixation strength was tested in a custom testing jig. Each shoulder underwent 1000 cycles each of low and then high load testing. Gap displacement was measured at anterior and posterior sites of the repair with digital video tracking of paired reflective markers and recorded at predetermined cycle intervals. Results: There were no statistically significant differences in gap formation at the repair sites under low or high load conditions between TOE-SB and TO techniques. The mean maximal gap formation of the repairs during low load testing in the TOE-SB and TO constructs was 0.93 ± 0.88 mm and 0.55 ± 0.22 mm, respectively ( P = .505). The mean maximal gap formation during high load testing in the TOE-SB and TO constructs was 2.04 ± 1.10 mm and 2.28 ± 1.62 mm, respectively ( P = .517). The most significant increase in gap distance occurred at the transition from low load to high load in both constructs. Most of the incremental displacement occurred within the first 100 cycles for both high and low load testing ( P < .001). Conclusion: The arthroscopic TOE-SB technique is comparable in initial fixation strength to the traditional TO simple suture repair technique. Clinical Relevance: Arthroscopic techniques can achieve initial fixation strength comparable with traditional TO techniques performed without suture anchors.

Background: Radiographic stress testing using both the anterior drawer (AD) and talar tilt (TT) technique is a widely accepted means of assessing ankle instability. The purpose of this study was to investigate the accuracy of plain film radiography in measuring translation of the talus during the AD test and the rotation of the talus during TT stress testing. In addition to determining the true accuracy of radiologic assessment in two planes, our goal was to further define instability in the sagittal, coronal and transverse planes. Methods: Twenty lower extremity specimens were placed in a Telos ankle stress apparatus, and respective lateral and AP radiographs were taken during simulated AD and TT testing. Positional measurements were calculated from the films. Next, a three-dimensional tracking system was used to calculate these displacements. The anterior talofibular ligament and calcaneofibular ligament were sectioned to simulate an unstable ankle, followed by repeat measurement using both methods. Movement calculated using the three dimensional system was compared to that of plain radiographs using a paired t-test. Results: Mean positional changes determined by plain film radiographs were found to be significantly lower than those calculated by the three-dimensional system in both AD and TT tests in the intact and sectioned states ( p< 0.001). Conclusion: Radiographic stress testing assessment of ankle instability appears to be much less accurate than previously believed. Clinical Relevance: Compared to values calculated with the 3D system, radiographic measurements may underestimate the true magnitude of TT and AD changes which could influence clinical decision making.

Internal impingement is a term used to describe the pathologic contact of the undersurface of the rotator cuff with the glenoid. It typically occurs in overhead athletes, particularly throwers. In these athletes, the bones and soft tissues adapt to allow these athletes to have a supraphysiologic range of motion. In many athletes, these changes may lead to symptoms of internal impingement. This article discusses the background, biomechanics, pathophysiology, clinical and radiographic assessment, treatments, and outcomes of this disorder.

Aims Tako-Tsubo cardiomyopathy (TTC) is characterized by rapid regeneration of contractile dysfunction. From recent studies it is known that excessive catecholamine levels due to emotional or physical stress might play a central role. After sympathetic activation, the PIK3/AKT pathway is a key regulator of many cellular responses, including cytoprotective effects. Thus, the purpose of this study was to investigate whether the PIK3/AKT pathway plays a pivotal role in TTC. Methods and results A total of 16 consecutive patients diagnosed with TTC were studied. Left ventricular biopsies were taken during the acute phase and after functional recovery. Specimens were examined by quantitative RT–PCR and western blotting. Representative genes of the PI3K/AKT pathway (PIK3-R1, PTEN, GSK3β, mTOR, PP2A, eIF4E) were compared with left ventricular controls from non-transplanted healthy hearts. PI3K expression was increased during the acute phase and after functional recovery. AKT protein levels were unaltered, but phosphorylation significantly increased during the acute phase. Both PTEN (PI3K antagonist) and PP2 (unspecific phosphatase) were down-regulated. Phosphorylation of the PI3K/AKT downstream target mTOR was increased, while expression of both GSK3 isoforms was decreased. The Bax/Bcl2 ratio was increased in the acute and recovery phases. Conclusion PI3K/AKT signalling is activated in TTC. This activated cell survival cascade might protect cardiomyocytes from cell death and also contribute to rapid regeneration in TTC.

Background: The current clinical standard for the surgical treatment of ankle instability remains the open modified Broström procedure. Modern advents in arthroscopic technology have allowed physicians to perform certain foot and ankle procedures arthroscopically as opposed to traditional open approaches. Methods: Twenty matched lower extremity cadaver specimens were obtained. Steinman pins were inserted into the tibia and talus with 6 sensors affixed to each pin. Specimens were placed in a Telos ankle stress apparatus in an anteroposterior and then lateral position, while a 1.7 N-m load was applied. For each of these tests, movement of the sensors was measured in 3 planes using the Optotrak Computer Navigation System. Changes in position were calculated and compared with the unloaded state. The anteriortalofibular ligament and the calcaneofibular ligament were thereafter sectioned from the fibula. The aforementioned measurements in the loaded and unloaded states were repeated on the specimens. The sectioned ligaments were then repaired using 2 corkscrew anchors. Ten specimens were repaired using a standard open Broström-type repair, while the matched pairs were repaired using an arthroscopic technique. Measurements were repeated and compared using a paired t test. Results: There was a statistically significant difference between the sectioned state and the other 3 states ( P < .05). There were no statistically significant differences between the intact state and either the open or arthroscopic state ( P > .05). There were no significant differences between the open and arthroscopic repairs with respect to translation and total combined motion during the talar tilt test ( P > .05). Statistically significant differences were demonstrated between the 2 methods in 3 specific axes of movement during talar tilt ( P = .04). Conclusion: Biomechanically effective ankle stabilization may be amenable to a minimally invasive approach. Clinical Relevance: A minimally invasive, arthroscopic approach can be considered for treating patients with lateral ankle instability who have failed conservative treatment.

Posterior sternoclavicular dislocations are rare but serious injuries. The proximity of the medial clavicle to the vital structures of the mediastinum warrants caution with management of the injury. Radiographs are the initial imaging test, though computed tomography and magnetic resonance imaging are essential for diagnosis and preoperative planning. This paper presents an efficient diagnostic approach and effective technique of closed reduction of posterior sternoclavicular dislocations with a brief review of open and closed reduction procedures.

Tako-Tsubo cardiomyopathy (TTC) is characterized by the sudden onset of severe left ventricular contractile dysfunction following profound emotional or physical stress. The underlying pathomechanism still remains to be elucidated. In this case we present a, to date, unique case of a female patient suffering from an episode of major depression who shows characteristic features of TTC.

The aim of this study is to evaluate the mechanical properties of a revision anterior cruciate ligament (ACL) reconstruction after redrilling the original tibial bone tunnel through a retained composite screw compared with initial soft tissue graft fixation. A total of 24 porcine tendons were fixed to porcine tibial tunnels with a 10 × 35 mm composite interference screw. Following the pullout test, a revision tunnel was drilled through the first interference screw and a second graft was fixed in the bone tunnel using a larger composite screw (11 × 35 mm). Following insertion of the revision screw, the graft was reloaded as described for the primary reconstruction. Load versus displacement data were recorded for each test. There were no significant differences between the primary and revision reconstruction constructs for yield load (p = 0.62), linear stiffness (p = 0.18), maximum failure load (p = 0.57), and yield displacement (p = 0.46). These results indicate that the mechanical properties of tibial fixation for ACL reconstruction with a composite screw following a revision provide similar fixation compared with initial reconstruction in this model. Revising a failed composite ACL construct by means of overdrilling and reinstrumenting may provide fixation equivalent to the initial reconstruction.

Vesicular Stomatitis Virus (VSV) is a potent replication competent oncolytic virus (OV). Most individuals do not have pre-existing anti-VSV antibodies, making VSV an ideal OV for treatment of disseminated cancer. To tailor the virus for systemic use, VSV-IFNb-NIS was attenuated through genetic modification to encode interferon beta which restricts virus replication in nontransformed cells and a sodium iodide symporter (NIS) reporter gene to enable real time noninvasive imaging of the sites of virus infection in patients. Preclinical studies in mice show that, in contrast to expectations, dose limiting toxicity was hepatotoxicity, not neurotoxicity. To investigate the mechanism(s) underlying VSV induced hepatotoxicity, we first sought to determine if liver damage was due to interactions with viral particles or required virus infection.C57BL/6 mice were given saline, 109 TCID50 VSV-mIFNb-NIS or equivalent amounts of inactivated VSV-mIFNb-NIS intravenously. There was a significant increase in ALT and AST at 24h while no significant change was found in the animals receiving inactivated VSV. Studies with adenoviruses showed that Ad-induced hepatotoxicity was attenuated by depletion of macrophages in the liver and spleen using clodronate liposomes. Our studies in clodronate treated C57BL/6 mice showed even higher levels of ALT and AST enzymes in the blood with significantly increased cell damage in the liver and spleen by 24h if mice were given 109 VSV-IFNb-NIS. In contrast, ALT/AST levels did not change significantly in mice given heat inactivated VSV (104 infectious units but the same number of viral particles as the 109 stock). Similar data were also observed in Balb/c mice. In conclusion, our studies indicate that dose limiting toxicity from IV administration of high dose (4×1010 TCID50/kg) VSV-mIFNb-NIS in a mouse is not neurotoxicity, but hepatotoxicity. The mechanism of the hepatotoxicity is direct infection and killing of hepatocytes by live virus, and not due to the interaction of viral particles with macrophages and Kupffer cells. Hence, in contrast to adenovirus dosing (viral particles/kg), our data suggest that VSV dosing should be calibrated in units of infectious virus (TCID50/kg) and not numbers of viral particles per test subject. View Large Image | Download PowerPoint Slide View Large Image | Download PowerPoint Slide

We identified lbpB , encoding the lipoprotein component of the meningococcal lactoferrin receptor. An LbpB mutant was unable to acquire Fe from lactoferrin and exhibits decreased surface binding to lactoferrin. Primer extension and reverse transcription-PCR analysis indicate that lbpB and lbpA are cotranscribed on a polycistronic Fe-repressible mRNA.

The objective of this study was to evaluate the mechanical properties of soft-tissue grafts following a single interference screw insertion of 4 different commercially available bioabsorbable interference screws. Twenty-four bovine proximal tibiae (12 matched pairs) were prepared and sagittally split to make 48 bone samples for testing. Tibiae were prepared for a 9 mm porcine tendon graft and were instrumented with 1 of 4 commercially available 10 x 35 mm composite screws, each with a different thread design. The samples were tensile loaded to failure at 200 mm/min and values for yield load, maximum load, and stiffness were recorded to quantify any differences on the function of the grafts. No graft showed macroscopic evidence of laceration following screw insertion and there were no statistically significant differences for yield load (P = .41), maximum load (P = .35), or stiffness (P = .68) among the different screw types. There is no significant difference in the mechanical properties of an anterior cruciate ligament graft following insertion of the 4 bioabsorbable screws tested in this study, in terms of yield load, stiffness, or failure load.

Background: The traditional Brostrom repair and the modified Brostrom-Gould repair are 2 historically reliable procedures used to address lateral ankle instability. The purpose of this study was to evaluate the biomechanical stability conferred by the Brostrom repair as compared to the Brostrom-Gould modification in an unstable cadaveric ankle model. Methods: A total of 10 cadaveric specimens were placed in a Telos ankle stress apparatus in an anterior-posterior position and then in a lateral position, while a 170 N load was applied to simulate anterior drawer (AD) and talar tilt (TT) tests, respectively. In both circumstances, the ankle was held in 15 degrees of plantarflexion, neutral, and 15 degrees of dorsiflexion, while the movement of the sensors was measured using a video motion analysis system. Measurement of the translation between the talus and tibia in the AD test and the angle between the tibia and talus in the TT test were calculated for specimens in the (1) intact, (2) sectioned (division of the ATFL and CFL), (3) Brostrom repair and (4) Gould modification states. Results: When compared to both the repaired states and the intact states, the sectioned state demonstrated increased inversion and translation at all ankle positions during TT and AD testing. Furthermore, no significant differences were found between the intact state and either of the repaired states. Finally, no difference in the biomechanical stability could be identified between the traditional Brostrom repair and the modified Brostrom-Gould procedure. Conclusions: Our findings indicate that there is no significant biomechanical difference in initial ankle stability conferred by augmenting the traditional Brostrom repair with the Gould modification in this time-zero cadaveric model. Clinical Relevance: These data suggest that the additional reinforcement of an ankle’s lateral ligament complex repair of the ankle with the inferior extensor retinaculum may be marginal at the time of surgery.

A large portion of the sequences of type II DNA-(cytosine-C5)-methyltransferases (C5-MTases) represent highly conserved blocks of amino acids. General steps in the methylation reaction performed by C5-MTases have been found to be mediated by some of these domains. C5-MTases carry, in addition at the same relative location, a region variable in size and amino acid composition, part of which is associated with the capacity of each C5-MTase to recognize its characteristic target. Individual target-recognizing domains (TRDs) for the targets CCGG (M), CC(A/T)GG (E), GGCC (H), GCNGC (F) and G(G/A/T)GC(C/A/T)C (B) could be identified in the C-terminal part of the variable region of multispecific C5-MTases. With experiments reported here, we have established the organization of the variable regions of the multispecific MTases M.SPRI, M.phi3TI, M.H2I and M.rho 11SI at the resolution of individual amino acids. These regions comprise 204, 175, 268 and 268 amino acids, respectively. All variable regions are bipartite. They contain at their N-terminal side a very similar sequence of 71 amino acids. The integrity of this sequence must be assured to provide enzyme activity. Bracketed by 6-10 'linker' amino acids, they have, depending on the enzyme studied, towards their C-terminal end ensembles of individual TRDs of 38 (M), 39 (E), 40 (H), 44 (F) and 54 (B) amino acids. TRDs of different enzymes with equal specificity have the same size. TRDs do not overlap but are either separated by linker amino acids or abut each other.

Ultrasound elastography by acoustic radiation force impulse imaging (ARFI) is used in adults for non invasive measurement of liver stiffness, indicating liver diseases like fibrosis. To establish ARFI in children and adolescents we determined standard values of healthy liver tissue and analysed potentially influencing factors.132 patients between 0 and 17 years old were measured using ARFI. None of them had any liver disease or any other disease that could affect the liver secondarily. All patients had a normal ultrasound scan, a normal BMI and normal liver function tests. The mean value of all ARFI measurements was calculated and potentially influencing factors were analysed.The mean value of all ARFI elastography measurements was 1.16 m/sec (SD ± 0.14 m/sec). Neither age (p = 0.533) nor depth of measurement (p = 0.066) had no significant influence on ARFI values, whereas a significant effect of gender was found with lower ARFI values in females (p = 0.025), however, there was no significant interaction between age groups (before or after puberty) and gender (p = 0.276). There was an interlobar difference with lower values in the right liver lobe compared to the left (p = 0.036) and with a significantly lower variance (p 0.001). Consistend values were measured by different examiners (p = 0.108), however, the inter examiner variance deviated significantly (p 0.001).ARFI elastography is a reliable method to measure liver stiffness in children and adolescents. In relation to studies which analyse liver diseases, the standard value of 1.16 m/sec (± 0.14 m/sec) allows a differentiation of healthy versus pathological liver tissue.

Elasticρ0 photoproduction has been measured using the ZEUS detector at HERA. Untagged photoproduction events fromep interactions were used to measure the reactionγp→ρ0p(ρ0)→π+π−) at photon-proton centre-of-mass energies between 60 and 80 GeV and |t

We report on a measurement of the proton structure function F 2 in the range 3.5×10-5≤x≤4×10-3 and 1.5 GeV2≤Q 2≤15GeV2 at the ep collider HERA operating at a centre-of-mass energy of √s=300GeV. The rise of F 2 with decreasing x observed in the previous HERA measurements persists in this lower x and Q 2 range. The Q 2 evolution of F 2, even at the lowest Q 2 and x measured, is consistent with perturbative QCD. © 1996 Springer-Verlag.