Complex dynamic behaviors of the complex Lorenz system

AbstractThis study compares the dynamic behaviors of the Lorenz system with complex variables to that of the standard Lorenz system involving real variables. Different methodologies, including the Lyapunov Exponents spectrum, the bifurcation diagram, the first return map to the Poincaré section and topological entropy, were used to investigate and compare the behaviors of these two systems. The results show that expressing the Lorenz system in terms of complex variables leads to more distinguished behaviors, which could not be achieved in the Lorenz system with real variables, such as quasi-periodic and hyper-chaotic behaviors

Computed Tomographic measurement of distal femor rotation in Iranian population

Background: Proper rotation of components in total knee arthroplasty (TKA) will largely affect the postoperative outcome. Ethnical variation may affect rotational profile. We aimed to evaluate distal femur rotation in Iranian population using transepicondylar axes. Methods: From a total of 450 knee CT scans and via consecutive sampling, 150 qualified subjects with normal lower extremities alignment were selected comprising 96 (64) males and 54 (36) females aging 17-80 years. The posterior condylar angle and condylar twist angles were defined as angles between either surgical epicondylar axis (line connecting lateral epicondylar prominence and the medial sulcus) or clinical epicondylar axis (line connecting most prominent points of both epicondyle) and posterior conylar line. Data were compared among genders. Results: Average age of our samples was 43 years (ranging 11-80). Mean (±sd) values for posterior condylar angle and condylar twist angles were 2.35° (±1.34) and 5.77° (±1.70), respectively. The former variable was not discernible in twenty of our subjects because of obscure medial sulcus. Our findings were totally appeared similar to studies from other ethnicities and the observed minor differences may have originated from amount of osteoarthritis and malalignment. Conclusion: Overall, Iranian distal femur rotational profile was similar to other reports. Some minor observed differences may be partially due to samples' age and different amount of knee osteoarthritis. It is proposed to rely on several methods for determining rotational profile while performing TKA. Moreover, preoperative computed tomography should be fully scrutinized especially in severely osteoarthitic knees

Morphology of proximal tibia in iranian population and its correlation with available prostheses

Background: Total knee arthroplasty is a complex procedure aiming to relieve pain and improve function. It is critical to select prosthesis that best cover the bone surfaces. Ethnicity may affect fitness of the components mainly designed for Caucasian populations. This study aimed to evaluate morphometric features of proximal tibia in Iranian population. Methods: During 2013, 150 consecutive patients (96 males and 54 females) form orthopedics department of Rasoul-Akram hospital with knee CT scan were randomly enrolled. We entered cases with apparent normal extremity alignment and bone maturity. Cases with history of fracture or conditions affecting knee profile were excluded. Standard cuts were simulated on CT scan. Anteroposterior (AP), mediolateral (ML) and aspect ratio (ML/AP) were measured for general morphology. Medial and lateral AP distance of tibia and their distance to tibial center were measured for checking symmetry. Results: Mean age was 43.0± 10.4 years (rang 11-80). Males showed significantly larger values in ML dimension and aspect ratio than females under a given AP value (p<0.001). However, the aspect ratio was suggestive of similar configuration of proximal tibia profiles among genders. Totally, close correlations were observed among simulated cuts and size-matched tibial components of the prostheses. However, better coverage was provided by some brands via designing interchangeable components for a given dimension. Medial and lateral condyles of tibia were almost symmetrical. Conclusion: Our findings indicated that some alterations in the shape of the components are needed to provide optimal coverage in Iranian population. We propose symmetrical configuration in designing tibial components as well

Comparing the therapeutic effect of local corticosteroid injections and laser in treating coccyx pains (sacrum)

Coccydynia (pain in the coccyx or tailbone) is a fairly common pain in the bottom of backbone that spreads towards sacrum and lower legs. Supportive treatments, such as corticosteroids, use of muscle relaxants and correction of body position can help relieve the pain. In recent years, the use of laser is introduced as an effective method to reduce backbone pain. The purpose of this study is to compare the effects of corticosteroids and laser in treating tailbone pains. 61 patients with tailbone pain referred to the orthopedic clinic of Rasul Akram Hospital were entered into the study and randomly divided into two groups of laser and local corticosteroid injection. The mean difference in pain score was compared in both groups at the beginning of the study, end of the second week and end of the second month to determine the response to treatment. Data were analyzed using SPSS software. Of the patients enrolled, 24 were males (37.6) and 37 were females. The mean age of subjects studied was 36.16 years old. The mean difference in pain scores at the beginning of the study and at the end of the second month in the group treated by laser and corticosteroid was 2.54 and 3.8, respectively, that this difference was also statistically significant (P: 0.019) Effect of corticosteroid injection for pain relief was better than laser. The study should be done in a longer timeframe

Risk of superior gluteal nerve injury after using ante-grade femoral nailing

Antegrade intramedullary femoral nailing (AIFN) is used as the preferred treatment for diaphyseal and subtrochanteric femur fractures. Nevertheless, clinically important complications associated with obtaining nail entry including loss of hip abductor strength, chronic hip pain, heterotopic ossification and femoral head osteonecrosis have been previously shown.This study was aimed to evaluate the risk of injury to the superior gluteal nerve when Ante-grade femoral nailing is used for insertion. In current study, 25 patients with femoral shaft fractures were included in this study that 21 were male with an average age of 25.40 years, Also 4 cases were female with an average age of 28.20 years. The patients were between the ages of 93 to 05 years. EMG-MCV was taken from all patients and were reported by neurologist. Plain radiographs were taken from all patients. Pain intensity of patients in the last month were identified from 4 to 944 according to the patients statements. The frequency of patients with subjective lameness separately with or no signs was determined. In terms of the pain score, its average among all patients was calculated to be 4.92, while the average of 4.75 among men was calculated. Among women, the average was 5.60. All patients had a mean duration of 3.64 months for using crutches, that the average duration of 3.80 months for men and 3 months for women were calculated.In terms of subjective limping, 15 patients (60) complained from limping, while 10 people were not affected (40 ), of which, 12 patients (80) was belonged to men group and 3 patients (20) were assigned in women group. 5 patients were diagnosed with atrophy of gluteus medius and gluteus minimus muscles that, 3 patients were male (60) and 2 cases (40) were women respectively. EMG-NCV indicated that the Superior gluteal nerve injury had occurred in 2 patients (8) and myogenic damage of gluteus medius and gluteus minimus muscles in 5 patients (20). Our study indicated that the superior gluteal nerve injury had occurred in 2 8 of patients and myogenic damage of gluteus medius and gluteus minimus muscles in 20

Comparing the Intramedullary Nailing Method Versus Dynamic Hip Screw in Treatment of Unstable Intertrochanteric Fractures

INTRODUCTION: Dynamic Hip Screw fixation is currently considered as a standard treatment for pre-trochanteric fractures; however, due to the long-term hospitalization and some other complications, some researchers have proposed intramedullary nailing as the alternative surgical treatment. The aim of this study was to compare and examine the consequences of the using intramedullary nailing method versus Dynamic Hip Screw. METHODS: In this study 114 patients with unstable Intertrochanteric fracture refer to Rasoul Akram hospital during 2011 to 2013 has been selected. After reduction, fixation surgery with PFN nail (60 patients) and Dynamic Hip Screw (54 patients) has been performed. All patients were screen during surgery and six months after surgery and some parameters like, bleeding, union, as well as complications such as collapse, varus and medialization of the distal fragment were record and patients. RESULTS: About some parameters like cutting length, surgery duration, bleeding there were significant differences between two groups. In six months follow up period 2 patinas from nail and 8 patients from DHS group had non-union. Also from the point of radiologic and clinical parameters, like anterior thigh pain, cut out, medialization of the distal fragment, collapse of the neck, walking recovery and daily activities were significant between two groups. CONCLUSION: Due to the reduced hospital stay in intramedullary nailing method and the necessity of doing repeated surgery and applying intramedullary nailing when the patients are not treated with external fixation, the researchers recommend intramedullary nailing as the first option in treating such patients

Short-term Outcomes of Induced Membrane Technique in Treatment of Long Bone Defects in Iran

INTRODUCTION: Severe defects in long bones can be caused by several factors such as trauma that lead to open wound and secondary infections after surgery. Induced membrane technique is one of the therapeutic strategies that can be used for these patients. Due to importance of this method and lack of information about this technique in Iran. AIM: this study was performed to investigate technical strengths and weakness of induced membrane technique. MATERIAL AND METHODS: This case series study conducted on 21 patients with bone defects in the femur and tibia and metatarsal bones referred to orthopedic clinic of Rasoul Akram Hospital, Tehran, Iran, for induced membrane surgery in 2012-2015. Demographic and clinical data were obtained using history, clinical examinations and observations for each patient. Union achievement was the main outcome of this study, which was confirmed by radiographic findings and physical examination. Obtained data was analyzed by SPSS ver. 16. RESULTS: All patients were male except one and their mean age was 30.52 years old. Bone defects were in tibia, femur and metatarsus in 9, 9 and 3 patients, respectively. Three patients received soft tissue reconstruction with flap before induced membrane surgery. Age, defects size, cigarette addiction and drug use and delay to start the treatment had no significant effect on union status. In total, 90 of patients had successful surgery. CONCLUSION: using induced membrane technique in patients with defects in their long bone such as tibia, femur and metatarsus would lead to high success for reconstruction

Evaluation of Patellar Position before and After Medial Opening Wedge High Tibial Osteotomy: Radiographic and Computed Tomography Findings

INTRODUCTION: Genovarum is a common orthopedic problem. Its optimal prompt treatment is an issue of importance. AIM: This study was conducted to determine the radiographic changes in patella bone before and after open wedge high tibial osteotomy. MATERIAL AND METHODS: In this quasi-experimental study, 43 patients were enrolled and underwent open wedge high tibial osteotomy and the radiographic and CT-scan indices including Q-Angle, Congruence Angle, Insall-Salvati index, and TTTG were measured and compared before and after surgery. RESULTS: The result revealed that all indices including Q-Angle, Congruence Angle, Insull-Salvati index, and TTTG were not significantly differed across the study (P > 0.05). There was no difference between DLFA values before and after the operation (P> 0.05), while MPTA values were significantly different before and after operation (p <0.001). CONCLUSIONS: Totally it may be concluded that imaging indices are not differed after open wedge high tibial osteotomy and monitoring for them is not necessary and they would have no prognostic role

Sagittal spinopelvic alignment in asymptomatic iranian adults aged 18 to 40 years

Background: Recent studies have revealed the increasing importance of sagittal spinopelvic alignment. Knowing the values of sagittal spinopelvic parameters, which are affected by ethnicity, is essential in the normal asymptomatic population. In the current study, these parameters were measured in a sample of asymptomatic Iranian population. Methods: Seventy asymptomatic participants without complaint of musculoskeletal problems were enrolled. They had no complaint about musculoskeletal problems. Lateral full-length spinal and pelvic x-rays were taken. The following parameters were measured on x-rays and presented as mean ± standard deviation: pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT), lumbar lordosis (LL), thoracic kyphosis (TK), lumbar tilt (LT) and thoracic tilt (TT). Results: The population consisted of 37 males and 33 females aged 26.6 ± 4.27 years. The mean values of PI, SS, PT, LL, TK, LT, and TT were 44.5 ± 10.1, 35.4 ± 6.7, 9.1 ± 7.9, 41.9 ± 14.7, 28.8 ± 8.3, 11.9 ± 7.4 and -7.5 ± 5.7 (median: -10; 5th percentile: -14; 95th percentile: 4.4) degrees, respectively. The variables were similar between males and females except for LL which was significantly higher in females (37.8 ± 16.5 versus 46.5 ± 11; P = 0.013). In addition, the linear regression model revealed age to be independently related with PI (beta = 0.344; P = 0.004) and PT (beta = 0.366; P = 0.002). PI (r = 0.344, P = 0.004) and PT (r = 0.359, P = 0.002) were positively correlated with age. Additionally, PI was positively correlated to SS, PT and LL and negatively to TT. Conclusion: These findings may be used as referential values for sagittal spinopelvic parameters in the Iranian population. The positive correlation of PI with age questions the constancy of PI throughout life. However, larger studies are required. © 2020 The Author(s). This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons. org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

Evaluation of inflammatory response in patients undergoing surgical treatment for early and delayed femoral fractures

Introduction: It has been shown that long bone fractures are correlated with the inflammatory response. In the initial injury, surgical reduction and fixation of fractures induce the immunoinflammatory response. This study aimed to evaluate serum variation of inflammatory markers in patients undergoing surgical treatment for early and delayed femoral fractures. Material and methods: This study aimed to evaluate serum variation of inflammatory markers in patients undergoing surgical treatment for early and delayed femoral fractures. The patients were randomly divided into two groups using the method of block randomization including early surgery (within 24 h) and delayed surgery (after 48 h). Serum levels of inflammatory markers in both groups including interleukin (IL)-1, 5, 6, tumor necrosis factor α (TNF-α) and interferon γ (IFN-γ) were determined using specific kits. From each patient 10 ml blood was collected for cytokine assay in their serum. Results: Our findings suggest that serum levels of IL-8 were markedly decreased from 12 h until 48 h postoperatively (p < 0.05). Moreover, the results indicated that serum levels of TNF-α were significantly increased in the early hours, but after 48 h a decreasing trend was detected (p < 0.05). Furthermore, serum levels of IL-10, IFN-γ, and IL-6 were significantly increased from 12 h until 48 h postoperatively (p < 0.05). Conclusions: The inflammatory status of the patient may be a useful adjunct in clinical decisions. With an improved understanding of the molecular basis of the inflammatory response, and by identifying relevant clinical markers of inflammation, surgeons can better manage the timing of surgical stabilization. © 2016 Termedia & Banach