Anchorage Research for CFRP Tendons: A Review.

Carbon fiber reinforced polymer (CFRP) tendons are composite materials that offer significant advantages in terms of tensile strength and lightweight properties. They are being increasingly utilized in the construction industry, particularly in bridge cables and building structures. However, due to their relatively poor transverse mechanical properties compared to steel cables, securing these tendons with anchors presents a challenge. This paper reviews the structure and force characteristics of three types of anchors for CFRP tendons-clamping anchorage, bonded anchorage, and composite anchorage-analyzes and summarizes the anchorage characteristics and damage mechanisms of each type of anchorage, and highlights that the optimization of the mechanical properties of the tendons is key to the design and research of anchoring systems. The new composite anchorage offers comprehensive advantages, such as minimal tendon damage at the anchorage section, more uniform stress distribution, and better anchorage performance, despite being more complex in design compared to single-type anchorages. However, there remain challenges and research gaps in testing and validating these anchoring systems under realistic loading and environmental conditions, including impacts, cyclic stresses, humidity, and high temperatures. Future efforts should focus on developing new testing techniques and models to simulate real-world conditions, enabling more accurate assessments of anchorage performance and longevity. By doing so, we can fully harness the mechanical properties of CFRP tendons and further enhance the safety and efficiency of our built environment.

A non-invasive nanobody probe for high precision mapping of Lck spatial distribution.

The tyrosine kinase Lck is mandatory for initiating signaling responses downstream the antigenic T cell receptor (TCR). Numerous studies have shown that a prerequisite for efficient and well-balanced Lck regulation and function is its finely orchestrated spatial distribution pattern, especially at the plane of the plasma membrane. There is a wealth of knowledge on Lck localization sites, preference for specialized lipid microenvironments and colocalization partners. However, several questions concerning the spatial organization of its differentially phosphorylated conformers and the dynamics of their juxtaposition in relation to ligated and non-ligated TCRs remain elusive. In this brief report we introduce a non-invasive nanobody-based approach for mapping Lck subcellular allocation with high precision. Our initial data using this methodology, provide insight into the topology of Lck in resting T cells and its confined localization in a strictly delimited environment within the plane of the plasma membrane.

Minimum 10-year follow-up outcomes of arthroscopic Bankart's repair with metallic anchors: Reliable results with low redislocation rates.

BACKGROUND: With stiff competition from alternative albeit more expensive counterparts, it has become important to establish the applicability of metallic anchors for shoulder instability in the modern era. This can be accomplished, in part, by analysing long-term outcomes. AIM: To analyse minimum 10-year outcomes from 30 patients following arthroscopic anterior stabilisation using metallic anchors. METHODS: Prospectively collected data from arthroscopic Bankart repairs performed using metal anchors during 2007P-2010 were retrospectively analysed in this single-surgeon study. Comprehensive data collection included historical and clinical findings, dislocation details, operative specifics, and follow-up radiological and clinical findings including shoulder scores. The primary outcomes were patient-reported scores (Constant, American Shoulder and Elbow Surgeons [ASES], and Rowe scores) and pain and instability on a visual analogue scale (VAS). RESULTS: A 3% recurrence rate of dislocation was noted at the final follow-up. Total constant scores at 10 years postoperatively measured between 76 and 100 (mean 89) were significantly better than preoperative scores (mean 62.7). Congruous improvements were also noted in the Rowe and ASES scores and VAS at the 10-year review. CONCLUSION: Reliable long-term outcomes with metallic anchors in surgery for shoulder instability can be expected. Our results provide additional evidence of their continued, cost-effective presence in the modern scenario.

Surveying Colombian Speech-Language Pathologists on their Reported Training & Practices of Auditory-Perceptual Evaluation of Voice

Objective: To explore the training and use of auditory perceptual evaluation of the voice reported by Colombian speech-language pathologists. Study Design: Cross-sectional observational research with a quantitative approach. Methods: A digital questionnaire was designed and distributed to gather information regarding professionals' training process and implementation of auditory-perceptual evaluation procedures. Descriptive statistics were applied, and several generalized linear models were adjusted to determine the influence of certain variables on others. Results: The survey received responses from 40 speech-language pathologists, revealing that the most used scales for training and evaluating vocal quality within this group are direct magnitude estimations (82.5% and 77.5%). Similarly, in this group, the tasks most frequently used to train and use as an evaluation strategy are vowel assessments (38%) followed by spontaneous speech (30%). Practitioners of this group were mostly trained using a conceptual framework involving multiple exposures to rating (42.5%). The use of direct magnitude estimation in training with a normal voice showed significance (p = 0.015), as did the use of the vowel /i/ in training with an equal-appearing interval (p = 0.013). The statistical models relating the scale used to the scale on which participants were trained were also significant (p < 0.05). Conclusions: The GRBAS scale is the training tool most used by the group of speech-language pathologists of the study group in Colombia. Future efforts should focus on improving training practices for auditory-perceptual evaluation, exploring alternative conceptual frameworks, and incorporating external references to enhance validity and reliability.

Objetivo: Explorar los reportes de fonoaudiólogos colombianos acerca del entrenamiento y uso de la evaluación perceptual auditiva de la voz. Diseño de estudio: Se eligió un diseño de investigación observacional transversal con un enfoque cuantitativo. Metodología: Se diseñó y distribuyó un cuestionario digital para recopilar información sobre el proceso de formación de los profesionales y la implementación de procedimientos de evaluación perceptual auditiva. Se aplicaron estadísticas descriptivas y se ajustaron varios modelos lineales generalizados para determinar la influencia de ciertas variables en otras. Resultados: La encuesta recibió respuestas de 40 fonoaudiólogos, revelando que las escalas más utilizadas para la formación y la evaluación de la calidad vocal en el grupo son las estimaciones de magnitud directa (82.5% y 77.5%). Del mismo modo, en este grupo las tareas más frecuentemente utilizadas para la formación y el uso como estrategia de evaluación son las vocales (38%), seguidas por el habla espontánea (30%). La mayoría de los profesionales del grupo fueron formados utilizando un marco conceptual que involucra múltiples exposiciones a la calificación (42.5%). El uso de la estimación de magnitud directa en la formación con una voz normal mostró significancia (p = 0.015), al igual que el uso de la vocal /i/ en la formación con intervalos de igual apariencia (p = 0.013). Los modelos estadísticos que relacionan la escala utilizada con la escala en la que los participantes fueron entrenados también fueron significativos (p < 0.05). Conclusiones: La escala GRBAS es la herramienta de formación más utilizada por el grupo de fonoaudiólogos del estudio. Los esfuerzos futuros deberían centrarse en mejorar las prácticas de formación para la evaluación perceptual auditiva, explorar marcos conceptuales alternativos e incorporar referencias externas para mejorar la validez y la confiabilidad.

Knotless Anchor with FiberTape® for Fixing Pure Distal Patellar Tendon Rupture. A Case Report.

Introduction: The extensor mechanism and patellar tendon (PT) are considered essential components. Adult PT avulsion from the tibial tubercle is uncommon, with little information in the literature. Technical challenges arise during injury management. Knotless anchors have several applications in treating tendon injuries, such as the rotator cuff, distal biceps, and quadriceps tendons but were not used to repair distal PT avulsions. Case Report: A 50-year-old male patient, an active adult, presented to emergency department with significant right knee pain, giving away and limitation of range of motion (ROM) that had started after he sustained direct trauma with a ground-level fall on his knee that morning. Conclusion: In this paper, we report a case and describe a technique to manage a rare presentation of pure distal PT rupture without an avulsion fracture using knotless anchors with FiberTape®, which showed excellent results. To the best of our knowledge, this technique has never been used before in such injury and anatomical location. At 2 years of follow-up, the patient is free of complaints with almost full ROM at the knee and back to his standard daily life activity.

Zinc-Ion Anchor Induced Highly Reversible Zn Anodes for High Performance Zn-Ion Batteries.

Unstable Zn interface with serious detrimental parasitic side-reactions and uncontrollable Zn dendrites severely plagues the practical application of aqueous zinc-ion batteries. The interface stability was closely related to the electrolyte configuration and Zn2+ depositional behavior. In this work, a unique Zn-ion anchoring strategy is originally proposed to manipulate the coordination structure of solvated Zn-ions and guide the Zn-ion depositional behavior. Specifically, the amphoteric charged ion additives (denoted as DM), which act as zinc-ion anchors, can tightly absorb on the Zn surface to guide the uniform zinc-ion distribution by using its positively charged -NR4 + groups. While the negatively charged -SO3 - groups of DM on the other hand, reduces the active water molecules within solvation sheaths of Zn-ions. Benefiting from the special synergistic effect, Zn metal exhibits highly ordered and compact (002) Zn deposition and negligible side-reactions. As a result, the advanced Zn||Zn symmetric cell delivers extraordinarily 7000 hours long lifespan (0.25 mA cm-2, 0.25 mAh cm-2). Additionally, based on this strategy, the NH4V4O10||Zn pouch-cell with low negative/positive capacity ratio (N/P ratio=2.98) maintains 80.4 % capacity retention for 180 cycles. A more practical 4 cm*4 cm sized pouch-cell could be steadily cycled in a high output capacity of 37.0 mAh over 50 cycles.

Interpreting Stroke-Impaired Electromyography Patterns through Explainable Artificial Intelligence.

Electromyography (EMG) proves invaluable myoelectric manifestation in identifying neuromuscular alterations resulting from ischemic strokes, serving as a potential marker for diagnostics of gait impairments caused by ischemia. This study aims to develop an interpretable machine learning (ML) framework capable of distinguishing between the myoelectric patterns of stroke patients and those of healthy individuals through Explainable Artificial Intelligence (XAI) techniques. The research included 48 stroke patients (average age 70.6 years, 65% male) undergoing treatment at a rehabilitation center, alongside 75 healthy adults (average age 76.3 years, 32% male) as the control group. EMG signals were recorded from wearable devices positioned on the bicep femoris and lateral gastrocnemius muscles of both lower limbs during indoor ground walking in a gait laboratory. Boosting ML techniques were deployed to identify stroke-related gait impairments using EMG gait features. Furthermore, we employed XAI techniques, such as Shapley Additive Explanations (SHAP), Local Interpretable Model-Agnostic Explanations (LIME), and Anchors to interpret the role of EMG variables in the stroke-prediction models. Among the ML models assessed, the GBoost model demonstrated the highest classification performance (AUROC: 0.94) during cross-validation with the training dataset, and it also overperformed (AUROC: 0.92, accuracy: 85.26%) when evaluated using the testing EMG dataset. Through SHAP and LIME analyses, the study identified that EMG spectral features contributing to distinguishing the stroke group from the control group were associated with the right bicep femoris and lateral gastrocnemius muscles. This interpretable EMG-based stroke prediction model holds promise as an objective tool for predicting post-stroke gait impairments. Its potential application could greatly assist in managing post-stroke rehabilitation by providing reliable EMG biomarkers and address potential gait impairment in individuals recovering from ischemic stroke.

Clinical and radiological outcome after arthroscopic rotator cuff repair using PEEK-CF anchors.

PURPOSE: The goal of this study was to evaluate the clinical and radiological outcome after arthroscopic rotator cuff repair using new carbonfiber reinforced polyetheretherketone (CF-PEEK) suture anchors. METHODS: One hundred (n=100) patients with rotator cuff tears were enrolled at seven French hospitals between July 2019 and June 2020. Pain levels, Constant score and Subjective Shoulder Value (SSV) were taken preoperatively and 6months postoperatively. Ultrasonography (US) was performed at 6months postoperatively to evaluate tendon healing using the Sugaya classification. Statistical analysis was done with the Student t-test with 95% confidence intervals. RESULTS: One hundred patients of the 100 patients were followed at 6months. The mean SSV and Constant score improved from 40.1% preoperatively to 78% at 6months (p<0.0001) and from 43 points preoperatively to 65 points at 6months (p<0.0001), respectively. The mean level of pain, as measured with the visual analogue scale, decreased from 5.9 to 1.6 (p<0.001). There were no postoperative complications that resulted in revision surgery. CONCLUSION: The study showed good results at 6months follow-up using carbonfiber reinforced PEEK anchors with improved Constant and SSV scores as well as a high ultrasonographic tendon healing rate, making PEEK-CF anchors safe to use, comparable to commonly used anchors. LEVEL OF EVIDENCE: IV.

A biomechanical comparison of the double-row suture fixation and compression screw techniques in the treatment of lateral malleolar avulsion fracture.

Background: Avulsion fractures of fibula occur with ankle sprains. The purpose of this study was to compare the biomechanical characteristics of double-row suture versus compression screw techniques in treatment of lateral malleolar avulsion fracturelarger than 10 mm in size, which is typically not associated with an anterior talofibular ligament injury. Methods: We simulated lateral malleolus avulsion fractures in six matched pairs of 12 human cadaveric ankles. These were then randomly divided into two groups: a double-row fixation group and a compression screw group. Biomechanical testing was performed after surgical fixation. The foot was rotated from the neutral position toward inversion at a rate of 1°/s until 12.5 N-m or structural failure was reached. The final rotation torque, rotation angle, stiffness, and displacement of the ossicles were recorded. Results: No significant difference was found in the final rotation torque (7.60 ± 3.70 vs 7.23 ± 2.06 N-m, p = 0.87), rotation angle (43.61 ± 14.77° vs 40.93 ± 10.94°, p = 0.56), stiffness (0.19 ± 0.08 vs 0.13 ± 0.07, p = 0.33), or displacement (6.11 ± 5.23 vs 7.09 ± 5.93 mm, p = 0.77) between the two groups. Conclusions: The stability of the double-row suture fixation was equivalent to compression screw fixation in treating a lateral malleolar avulsion fracture larger than 10 mm in size with ligament injury, as determined by our biomechanical testing.

Chronic proximal ulnar collateral ligament injuries thumb-a case report.

A 55-year-old woman presented with multiple episodes of falls that injured her right thumb and restricted her daily activities because of pain and instability. Ultrasound found the rare proximal metacarpal UCL avulsion. The repair was done using suture anchors under wide-awake anaesthesia with no tourniquet (WALANT). The patient regained her thumb movements, got a stable MCP joint, and remained symptom-free at one year of follow-up. Proximal avulsion of the UCL is rare. Ultrasound confirms the avulsion, and surgical reconstruction under wide-awake anaesthesia allows the surgeon and the patient to assess and appreciate the MCP joint stability, thereby efficiently rehabilitating the patient. The functional outcome of proximal UCL repair is good. This report describes a rare presentation of the proximal metacarpal attachment avulsion injury of the ulnar collateral ligament (UCL) in a thumb and reviews the management.

Strengthening of Reinforced Concrete Non-Circular Columns with FRP.

Fiber reinforced polymer (FRP) strengthening in circular columns is known to be more effective than in rectangular and square columns because of the uniform distribution of confining pressure. This study explores the effectiveness of using carbon-FRP anchors to improve the confinement of square reinforced concrete (RC) columns strengthened with FRP. Sharp corners in non-circular columns cause stress concentration on the corners, reducing the effectiveness of strengthening. To address this, the study examines the impact of three different anchor configurations on two sizes of FRP-strengthened square columns. The results show that the proposed anchors distribute stresses to a greater extent, resulting in a more uniform distribution of stresses and better confinement. For the best performance, it is proposed that the anchor fans surround the corners of the cross section. Experimental findings and finite element analysis results using the Concrete Damage Plasticity model in the ABAQUS material library match.

Single anchor versus double anchor for arthroscopic anterior talofibular ligament repair: A systematic review and mate-analysis of cohort studies.

PURPOSE: To determine whether a double anchor is more effective than a single anchor in the surgical repair of the anterior talofibular ligament (ATFL) in patients with ankle instability. METHODS: This study searched PubMed, Embase and the Cochrane Library to identify potential studies that compared the clinical outcomes of double anchors and single anchors for ATFL repair from inception to July 31st, 2023. The study aligned with the 2020 Preferred Reporting Items for Systematic Reviews (PRISMA) guidelines and checklist. The Risk of Bias in Nonrandomized Studies-of Interventions (ROBINS-I) tool was used to evaluate methodologic quality and risk of bias. The meta-analysis was performed with random effects. Outcomes, including American Orthopaedic Foot & Ankle Society Score (AOFAS), Karlsson Ankle Functional Score (KAFS), Tegner activity score, return to sport rate, complications and revision surgery events, were recorded. RESULTS: A total of 845 articles were identified after an initial search of the three databases. Four retrospective studies involving 231 individuals were included for further analysis. There was no significant difference between the single-anchor group and the two-anchor group in terms of the AOFAS (risk ratio, -0.44, [-2.22; 1.34]) or KAFS (mean difference, -2.81, [-6.87; 1.25]). However, in terms of the Tegner activity score and the return to sport rate, the single-anchor group had significantly lower scores and longer times than the double-anchor group. No complications or revision surgery events were reported. CONCLUSIONS: In patients with chronic ankle instability, both single anchors and double anchors can provide good functional outcomes. For patients who participate in physically demanding sports, double anchors may be a superior option. LEVEL OF EVIDENCE: Level Ⅲ, meta-analysis of Level Ⅲ.

Construction of an Anchor and Training Sample Set for Auditory-Perceptual Voice Evaluation With the GRBAS-scale.

OBJECTIVE: The aim of this study is to construct a representative and comprehensive set of reliable anchor and training voice samples for all parameters and grades of the GRBAS-scale, in order to develop a standardized online training tool for perceptual voice evaluation. METHODS: 140 voice samples varying from normal to severely dysphonic, consisting of the vowel /a/ and a Dutch standard text, were recorded. Samples were duplicated and added to a data folder in random order. A panel of five highly experienced judges rated GRBAS parameters for each voice sample. Intra- and interrater reliability were determined using intraclass correlation coefficient (ICC) and percentage agreement. Samples with agreement percentages of >0.90 for at least one parameter were qualified as anchor voices, whereas samples with a percentage agreement between 0.70 and 0.80 were considered valid training samples. RESULTS: Intrarater reliability was moderate to good for all raters and parameters. Interrater reliability was good for parameter G and moderate for R, B, A and S. 83 samples were found to be valid anchor samples with 90-100% expert agreement for at least one parameter, covering all of the GRBAS parameter/score combinations. An additional 37 samples fulfilled the criteria for adoption in the online tool as a training sample, showing 70-80% agreement for one or more parameters. CONCLUSION: Based on well-defined and stringent selection criteria, this study identifies a substantial number of valid anchor and training voices that qualify for implementation in a standardized multi-level training tool for the auditory-perceptual evaluation of voice by means of the GRBAS scale.

A Multi-Pyridine-Anchored and -Linked Bilayer Photocathode for Water Reduction.

The development of efficient photocathodes is of critical importance for the constructions of promising tandem photo-electrochemical cells. Most known dye-sensitized photocathodes are prepared with the conventional carboxylic or phosphonic acid anchors and require the presence of other terminal linking groups to connect catalysts; they suffer from high synthetic difficulty and low adsorption stability in aqueous media. Here, a compact bilayer photocathode has been prepared by using a pyrene-based photosensitizer with multiple terminal pyridine moieties as both the anchoring and linking groups to connect a Co hydrogen-evolution catalyst to the NiO substrate. The catalyst and dye molecule are assembled in a layer-by-layer manner on NiO through the metal-pyridine coordination. This photocathode exhibits good dye adsorption stability in aqueous media. A stable cathodic photocurrent of 70 µA cm-2 was achieved, with H2 being generated at the photocathode under the visible-light irradiation. The Faraday efficiency of H2 evolution was estimated to be 9.1 %. Transient absorption spectral studies suggest that the interfacial hole transfer occurs within a few picoseconds. The integration of the organic photosensitizer with pyridine anchoring and linking groups is expected to provide a simple method for the fabrication of stable and efficient photocathodes.

Biodegradable vs nonbiodegradable suture anchors for rotator cuff repair: a systematic review and meta-analysis.

Purpose: The use of non-biodegradable suture anchors (NBSA) in arthroscopic rotator cuff repair (RCR) has increased significantly. However, several complications such as migration, chondral damage, revision, and imaging difficulties have been reported. Meanwhile, the effectiveness of biodegradable suture anchors (BSA) in overcoming such complications and achieving functional outcomes requires further study. Thus, we aim to compare the clinical outcomes and complications of RCR using BSA and NBSA using direct comparison studies. Methods: Two independent reviewers conducted systematic searches in PubMed, Embase, Cochrane Library, and Web of Science from conception to September 2022. Using the RoB 2 and ROBINS-I tools, we assessed the included studies for bias. We applied GRADE to appraise our evidence. Our PROSPERO registration number is CRD42022354347. Results: Six studies (two randomized controlled trials, one retrospective cohort, and three case-control studies) involving 423 patients were included (211 patients received BSA and 212 patients received NBSA). BSA was comparable to NBSA in forward flexion, abduction, external rotation, Constant-Murley score, and perianchor cyst formation (P = 0.97, 0.81, 0.56, 0.29, and 0.56, respectively). Retear rates were slightly higher while tendon healing was reduced in BSA compared to NBSA, but the differences were not significant (P = 0.35 and 0.35, respectively). Conclusion: BSA and NBSA appear to yield similar shoulder functions and complications in rotator cuff repairs.

Posterior Cruciate Ligament Avulsion with Posterior Tibial Rim Fracture: A Case Report.

Introduction: Posterior cruciate ligament (PCL) avulsion fractures are the most common type of isolated PCL injuries. Avulsion from the tibia is more common than femoral attachment. They can present as isolated tibial avulsion or as a component of posterior tibial rim fractures. The size, geometry of the fragment, and associated ligamentous injury dictate the method of fixation. Case Report: A 32-year-old patient presented with posterior rim tibial plateau fracture with PCL avulsion after a motor vehicle accident. We used Burke and Schaffer approach and fixed the ligamentous avulsion and rim fracture using high tensile sutures and knotless swivel lock anchors. Conclusion: PCL avulsions can present either as an isolated injury or as a part of a complex injury involving the anterior or posterior tibial rim. These complex injuries occur due to the hyperextension mechanism which results in either anterior tibial plateau compression fracture or posterior rim avulsion injuries. The treatment of such injuries requires addressing both ligamentous and bony components. The size, geometry of the fragment, and associated ligamentous injury dictate the method of fixation. We described the fixation of both ligamentous and rim avulsion using sutures and knotless anchors.

Clinical and radiological outcome of all-suture anchors in shoulder and elbow surgery.

Background: All-suture anchors (ASAs) are noted to cause various bone reactions when used in upper limb surgery but clinical implications are unknown. Methods: 88 shoulders and 151 elbows with a mean follow-up of 47.1 ± 17.7 months were invited for follow-up including clinical examination, questionnaires and radiographs. The anchor drill holes were radiographically assessed. Results: At final follow up, mean DASH was 12.9 ± 13.8 and mean VAS 2.2 ± 2.4 in the shoulder population. In the elbow group mean MEPS was 91.8 ± 12.7 and mean VAS 1.5 ± 1.9. Implant-specific complications were seen in 10 elbow cases but none in the shoulder group. The mean diameter of the 1.4 mm all-suture anchor drill hole was enlarged to 2.5 ± 1.4 mm in the shoulder group and to 2.9 ± 1.0 mm in the elbow group. 50% of the 1.4 mm anchor drill holes showed abnormal morphology but these morphologic changes did not correlate with clinical outcome, complications or reoperation rate. Discussion: Satisfying clinical outcomes are found in upper limb surgery using ASAs. Various bone changes are seen after implantation of an ASA, but these are not clinically relevant. Long-term consecutive follow-up data is required.

Performance of the Cement Grouting Material and Optimization of the Mix Proportion for the Free Section of the Prestressed Anchor Bar.

Increasing the water-cement ratio and water-reducer dosage of cement slurry enhances its fluidity. However, a high water-cement ratio diminishes the beneficial effects of water reducers on fluidity. The stone content of the slurry decreases as the water-reducer dosage increases. Additionally, the water-cement ratio significantly affects stone content. However, when the water-cement ratio exceeds a threshold value, stone content decreases. Furthermore, the threshold value of the water-cement ratio decreases with increasing water-reducer dosage. Without the addition of the water reducer, as the water-cement ratio increases the overall integrity of the grout stone decreases. The addition of the water reducer alters the surface pore distribution, wherein "uniform small pores" change to "localized large pores." Based on the multi-objective optimization of Matlab, the recommended optimal mix composition for a slow-setting cement slurry is a water-cement ratio of 0.25 and water-reducer dosage of 1.5%. With the use of this optimized mix composition, the stone content and compressive strength increase by 7.8% and 145.6%, respectively, compared to those obtained using the recommended mix ratio in the specifications. Additionally, all relevant performance parameters meet the requirements specified by previous standards.

SARS-Cov-2 related shoulder pain and stiffness associated to humeral osteolysis after arthroscopic rotator cuff repair: A case report.

INTRODUCTION AND IMPORTANCE: Complications using bioresorbable anchors in arthroscopic rotator cuff surgery include osteolysis, aseptic synovitis, and foreign body reaction. However, the precise triggering factors are unknown. CASE PRESENTATION: A healthy, 63-year-old male patient underwent rotator cuff repair using 7PLGA/b-TCP anchors. Nine months after surgery he returned to the senior author because of right shoulder pain and stiffness, pain in the right hand, foot and leg, and presence of erythematous patches at the aforementioned joints following SARS-Cov-2 infection, as well as increasing in blood inflammatory markers. Magnetic Resonance Arthrography (Arthro-MRI) showed no rotator cuff tendons re-tear but intra-articular synovitis, subacromial bursitis and humeral osteitis. A diagnostic arthroscopy, intra-articular fluid collection, biopsy and joint lavage was performed to rule out a septic arthritis. Co-amoxicillin 2.2 g intravenous treatment was administered following samples. Histological analysis of synovial tissue showed fibrin-exudative synovitis, while humeral bone biopsy showed an anchor resorption reaction. All microbiological analysis showed sterile samples. Three months post-lavage follow-up physical examination showed painless, recovered mobility, while Arthro-MRI showed a significant post-refixation remodeling of the rotator cuff tendons and reduction in humeral head osteitis and synovitis. CLINICAL DISCUSSION: The abrupt onset of symptomatology and the close chronological link with SARS-Cov-2 infection suggests a causal relationship between clinical and radiological manifestations and the infection itself, with clinical and radiological manifestation being a viral host response reaction to SARS-Cov-2 infection. CONCLUSION: Shoulder pain, stiffness and humeral osteitis could be manifestations of a viral host response to SARS-Cov-2 infection.

Reconstruction of medial patellofemoral ligament with adductor magnus tendon for recurrent patellar dislocation in children: a retrospective comparative cohort study.

BACKGROUND: The purpose of current retrospective study was to explore the outcomes of using the adductor magnus tendon to reconstruct the medial patellofemoral ligament in the treatment of recurrent patellar dislocation in children. METHOD: Thirty-two children with recurrent patellar dislocation were selected. Sixteen cases in the conservative group, seven males and nine females, with an average age of 11.81 ± 1.28 years; sixteen cases in the surgical group, eight males and eight females, with an average age of 11.56 ± 1.15 years. All patients had no surgery history. The IS index (> 1.2), Q angle (> 20°) and tibial tubercle-femoral trochlear groove (TT-TG) distance (> 20 mm) were measured by X-ray and MRI. The conservative group was treated with closed reduction and a brace, and the surgical group received surgical treatment. Two years after surgery, congruence angle (CA) (- 6° to 6°) and lateral patellofemoral angle (LPFA) (7.7°-18.7°) were measured by X-ray image and all children were evaluated based on Kujala and Lysholm scores. The re-dislocation rate was recorded. Analysis was performed by t test and chi-square with the statistical SPSS software. P < 0.05 was considered a statistically significant difference. Furthermore, we measured the length (mm) of the adductor tendon and MPFL in three knee cadaveric specimens, and also observed the positional relationship between the two structures. RESULT: There were no significant differences in sex, age, injury site between groups (P > 0.05). Patients in the two groups were followed up for 2 years in average. Among the 16 cases in the conservative group, 7 cases (43.75%) had recurrence of patellar dislocation, while none of recurrence in the surgical group (P < 0.05). The Lysholm score of the surgical group (94.63 ± 8.99) was significantly better than that of the conservative group (79.31 ± 18.90), and the Kujala score of the surgery group (95.25 ± 10.32) was also significantly better than that of the conservative group (77.06° ± 14.34°) (P < 0.05). The CA and LPFA of the two groups of patients after treatment were significantly recovered. The CA (- 5.81° ± 7.90°) in the surgical group was significantly better than that in the conservative group (20.94° ± 8.21°), and the LPFA (6.44° ± 3.22°) was also significantly better than that in the conservative group (- 9.18 ± 11.08), and the difference is statistically significant (P < 0.05). We found it through autopsy that adductor magnus tendon was 124.33 ± 1.53 mm long, MPFL was 48.67 ± 2.08 mm, and the femoral insertion of the adductor magnus tendon was adjacent to the MPFL femoral insertion. CONCLUSION: Reconstruction of Medial patellofemoral ligament with the adductor magnus tendon, fixing with PEEK suture anchors on the patellar side, can achieve satisfactory results in the treatment of children with recurrent patellar dislocation. Compared with conservative treatment, the rate of recurrence is lower and the stability of the patella is better.