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Background: Open and percutaneous repair surgeries are widely used for the Achilles tendon rupture. However, prior biomechanic studies of these 2 approaches have mixed conclusions; therefore, we designed a cadaver and finite element (FE) model biomechanical study to compare the mechanical differences between the percutaneous Achilles repair system (PARS) and Krackow open repair under tensile load and rotation. Methods: Sixteen Achilles tendons were extracted from fresh-frozen cadaver ankles and the calcaneums were fixed in mortar. A force control dynamic tensile mechanical test was performed at 1 Hz with 30- and 100-N cyclic loads. Initial intact baseline testing was followed by an incision on all Achilles tendons, 4 cm from the calcaneus insertion, which were then repaired using the PARS (n = 8) or Krackow (n = 8) method. Recorded force-displacement values were used to calculate mechanical parameters, and statistical significance of differences was determined by unpaired (between repair techniques) and paired (intact vs repaired) t tests. Material properties of the Achilles tendon in the FE model were modified and a 10-Nm flexion was simulated for intact and surgical groups. Results: No differences were found between intact tendons assigned to PARS or Krackow repairs in Young’s modulus ( P = .582) and stiffness ( P = .323). Pre- and postoperative Young’s modulus was significantly decreased for both groups (Intact 230.60±100.76 MPa vs PARS 142.44±37.37 MPa, P < .012; Intact 207.46±81.12 MPa vs Krackow109.43±27.63 MPa, P < .002). Stiffness decreased significantly after surgery for both groups (Intact 25.33±10.89 N/mm vs PARS 6.51±1.68 N/mm, P < .003; Intact 20.30±8.65 N/mm vs Krackow 5.97±1.30 N/mm, P < .003). PARS ultimate tensile strength was significantly higher than the Krackow (PARS 280.29±47.32 N vs Krackow 196.97±54.28 N, P < .003) but not significantly different in the ultimate tensile strain. PARS had a significantly lower postoperative gap compared to Krackow (PARS 9.75±5.87 mm vs Krackow 25.19±7.72 mm, P < .001). FE analysis predicted an increased talocalcaneal contact pressure, maximum principal stress, and rotation in the Krackow vs PARS models, respectively. Conclusion: Biomechanical parameters observed in this study through mechanical testing and FE analysis favor the selection of PARS over the Krackow repair based on better strength, higher failure force, and lower gap generation. Clinical Relevance: The study has analyzed two Achilles tendon repair methods using cadaver and numerical estimation and may help clinicians gain insight into selection of tendon repair approaches to generate better clinical outcomes.

Michelle Biehl,1 Paul Y Takahashi,2 Stephen S Cha,3 Rajeev Chaudhry,2 Ognjen Gajic,1 Bjorg Thorsteinsdottir2 1Division of Pulmonary and Critical Care Medicine, Department of Medicine, 2Division of Primary Care Internal Medicine, 3Health Sciences Research, Mayo Clinic, Rochester, MN, USA Rationale: Identifying patients at high risk of critical illness is necessary for the development and testing of strategies to prevent critical illness. The aim of this study was to determine the relationship between high elder risk assessment (ERA) score and critical illness requiring intensive care and to see if the ERA can be used as a prediction tool to identify elderly patients at the primary care visit who are at high risk of critical illness. Methods: A population-based historical cohort study was conducted in elderly patients (age >65 years) identified at the time of primary care visit in Rochester, MN, USA. Predictors including age, previous hospital days, and comorbid health conditions were identified from routine administrative data available in the electronic medical record. The main outcome was critical illness, defined as sepsis, need for mechanical ventilation, or death within 2 years of initial visit. Patients with an ERA score of 16 were considered to be at high risk. The discrimination of the ERA score was assessed using area under the receiver operating characteristic curve. Results: Of the 13,457 eligible patients, 9,872 gave consent for medical record review and had full information on intensive care unit utilization. The mean age was 75.8 years (standard deviation ±7.6 years), and 58% were female, 94% were Caucasian, 62% were married, and 13% were living in nursing homes. In the overall group, 417 patients (4.2%) suffered from critical illness. In the 1,134 patients with ERA >16, 154 (14%) suffered from critical illness. An ERA score ≥16 predicted critical illness (odds ratio 6.35; 95% confidence interval 3.51–11.48). The area under the receiver operating characteristic curve was 0.75, which indicated good discrimination. Conclusion: A simple model based on easily obtainable administrative data predicted critical illness in the next 2 years in elderly outpatients with up to 14% of the highest risk population suffering from critical illness. This model can facilitate efficient enrollment of patients into clinical programs such as care transition programs and studies aimed at the prevention of critical illness. It also can serve as a reminder to initiate advance care planning for high-risk elderly patients. External validation of this tool in different populations may enhance its generalizability. Keywords: aged, prognostication, critical care, mortality, elder risk assessment

Scaffold design plays an essential role in tissue engineering of articular cartilage by providing the appropriate mechanical and biological environment for chondrocytes to proliferate and function. Optimization of scaffold design to generate tissue-engineered cartilage has traditionally been conducted using in-vitro and in-vivo models. Recent advances in computational analysis allow us to significantly decrease the time and cost of scaffold optimization using finite element analysis (FEA). FEA is an in-silico analysis technique that allows for scaffold design optimization by predicting mechanical responses of cells and scaffolds under applied loads. Finite element analyses can potentially mimic the morphology of cartilage using mesh elements (tetrahedral, hexahedral), material properties (elastic, hyperelastic, poroelastic, composite), physiological loads by applying loading conditions (static, dynamic), and constitutive stress−strain equations (linear, porous−elastic, biphasic). Furthermore, FEA can be applied to the study of the effects of dynamic loading, material properties cell differentiation, cell activity, scaffold structure optimization, and interstitial fluid flow, in isolated or combined multi-scale models. This review covers recent studies and trends in the use of FEA for cartilage tissue engineering and scaffold design.

Objective: To compare the efficacy of Dexmedetomidine with Tramadol for shivering post-spinal anaesthesia. Study Design: Quasi-experimental study. Place and Duration of Study: Department of Anaesthesia, Combined Military Hospital, Rawalpindi Pakistan, from Jul to Dec 2020. Methodology: A total of 158 patients who underwent gynaecological, orthopaedic and general surgical procedures under spinal anaesthesia using 0.5% hyperbaric Bupivacaine 12-15 mg were included in the study. Out of these 158 patients, 64% (102 patients) developed shivering after spinal anaesthesia. These 102 patients were divided into two equal groups, i.e., Group-D (n=51), who received 0.5 μg/kg Dexmedetomidine and Group-T (n=51), who received 0.5 mg/kg tramadol. The response in the next 15 mins was evaluated objectively as “effective” or “non-effective” by the treating Anesthesiologist. Results: Dexmedetomidine and Tramadol were effective in treating shivering following spinal anaesthesia. Our study showed that Dexmedetomidine was more effective than Tramadol in treating shivering, with an effectiveness of 88.2 % shivering relief in Group-D and an effectiveness of 51 % shivering relief in Group-T. The effectiveness was significant in both groups, with statistical significance in Group-D compared to Group-T (p

Background Scrub typhus was once thought to be a disease of rural origin and was confined to specific pockets in South Asia. Early diagnosis and treatment is extremely important as it is associated with high mortality if left untreated. Aim To delineate the clinical and molecular epidemiology of scrub typhus in patients presenting with acute febrile illness from various parts of India. Methods During the study period of 5 years (October 2013 to October 2018), a total of 1742 patients with acute febrile illness <15 days were enrolled after taking informed consent. Patients were diagnosed using IgM Enzyme-linked immunosorbent assay (ELISA) based on the pre-determined region specific cut offs. Patients with positive IgM ELISA were also subjected to IgM Immunofluorescence assay and nested polymerase chain reaction (PCR) assay. The demographic and relevant clinical details of the patients were documented and analyzed. Results A total of 210 (12.1%) patients were diagnosed with scrub typhus. Of these, nested PCR was positive in only 85 patients. Sequencing and phylogenetic analysis showed that the predominant circulating genotypes were Gilliam and Karp. On multivariate analysis, acute respiratory distress syndrome, myocarditis, encephalitis/encephalopathy, jaundice and splenomegaly were significantly more common in those patients who were diagnosed with scrub typhus. A total of 14 patients diagnosed with scrub typhus succumbed to the illness. Conclusion Patients with fever, headache, pulmonary manifestations, CNS manifestations, myocarditis, transaminitis or thrombocytopenia presenting in the monsoon and post-monsoon season should be evaluated for scrub typhus irrespective of the geographical location in India. [ABSTRACT FROM AUTHOR]