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Electromyographic analysis of anterior cruciate deficient knees with and without functional bracing during lunge exercise
, Article Prosthetics and Orthotics International ; Volume 40, Issue 2 , 2016 , Pages 270-276 ; 03093646 (ISSN) ; Farahmand, F ; Rezaeian, T ; Ramsey, D. K ; Mousavi, S. M. E ; Sharif University of Technology
SAGE Publications Inc
2016
Abstract
Background: The use of functional knee braces for returning to sports or during demanding activities following anterior cruciate ligament rupture is common; yet despite being commonly prescribed, its mechanism of action remains unknown. Objectives: To examine the effect of functional knee braces on mean muscle activity when performing lunge exercises. Study design: Pre-/post-test (within-subject research design). Methods: A total of 10 male participants with unilateral isolated anterior cruciate ligament deficiency participated. Electromyographic activities of six muscles around the knee were recorded during lunge exercises, with and without wearing a custom functional knee brace. The lunge...
Cross-sectional area of human trunk paraspinal muscles before and after posterior lumbar surgery using magnetic resonance imaging
, Article European Spine Journal ; Volume 25, Issue 3 , 2016 , Pages 774-782 ; 09406719 (ISSN) ; Arjmand, N ; Shirazi Adl, A ; Farahmand, F ; Hashemi, H ; Bagheri, S ; Valizadeh, M ; Sharif University of Technology
Springer Verlag
Abstract
Atrogenic injuries to paraspinal muscles during the posterior lumbar surgery (PLS) cause a reduction in their cross-sectional areas (CSAs) and contractile densities over time post-surgery. This study aims to quantify such alterations. Method: Pre- and postoperative CSAs (~6 months interval) of all paraspinal muscles were measured in six patients undergoing PLS using a 3-T magnetic resonance (MR) scanner to quantify the alterations in geometrical and tissue effective contractile (non-fatty) CSAs of these muscles at all lumbar levels. To examine the presence of any confounding effects on recorded changes within ~7-month period, measurements were also carried out on ten healthy volunteers....
Comparison of the trunk-pelvis and lower extremities sagittal plane inter-segmental coordination and variability during walking in persons with and without chronic low back pain
, Article Human Movement Science ; Volume 52 , 2017 , Pages 55-66 ; 01679457 (ISSN) ; Kamali, F ; Razeghi, M ; Haghpanah, S. A ; Sharif University of Technology
Elsevier B.V
2017
Abstract
Inter-segmental coordination can be influenced by chronic low back pain (CLBP). The sagittal plane lower extremities inter-segmental coordination pattern and variability, in conjunction with the pelvis and trunk, were assessed in subjects with and without non-specific CLBP during free-speed walking. Kinematic data were collected from 10 non-specific CLBP and 10 non-CLBP control volunteers while the subjects were walking at their preferred speed. Sagittal plane time-normalized segmental angles and velocities were used to calculate continuous relative phase for each data point. Mean absolute relative phase (MARP) and deviation phase (DP) were derived to quantify the trunk-pelvis and bilateral...
Coordinated activities of trunk and upper extremity muscles during walker-assisted paraplegic gait: A synergy study
, Article Human Movement Science ; Volume 62 , 2018 , Pages 184-193 ; 01679457 (ISSN) ; Farahmand, F ; Arazpour, M ; Zohoor, H ; Sharif University of Technology
Elsevier B.V
2018
Abstract
Individuals with spinal cord injury (SCI) at lower thoracic levels might walk independently with the aid of mechanical orthoses and walker by using their unimpaired trunk and upper extremity muscles (TUEM). The required motor skills and the associated subtasks of the paraplegic locomotion, however, have not been well understood yet. The purpose of this study was to investigate the coordination of the TUEM activities throughout the paraplegic gait cycle using synergy analysis. For eight paraplegic individuals (30.6 ± 11.6 years; SCI level: T12), the kinematics data and the surface electromyography (EMG) signals of TUEM were recorded during 15 gait cycles. Non-negative matrix factorization...
P 134 – Absence of the patella has minimal effects on sagittal plane gait parameters
, Article Gait and Posture ; Volume 65 , 2018 , Pages 462-464 ; 09666362 (ISSN) ; Khandan, A ; Arab Baniasad, M ; Darbandi, H ; Vafaei, A. R ; Sharif University of Technology
Elsevier B.V
2018
Abstract
Patella is the latest addition to the animal's skeleton. It's role in normal walking has not been clearly defined. A 9-year-old girl with congenital absence of the patella was assessed using instrumented gait analysis. The results show a tendency for the limb for external rotation, which is more pronounced during swing. We suggest that the role of the patella is mainly to redirect the force of the quadriceps tendon medially. The classically described role, which is to increase the lever arm of the quadriceps tendon, was not confirmed in this study. © 2018 Elsevier B.V
Effects of cognitive load on the amount and temporal structure of postural sway variability in stroke survivors
, Article Experimental Brain Research ; Volume 236, Issue 1 , 2018 , Pages 285-296 ; 00144819 (ISSN) ; Khalaf, K ; Ghomashchi, H ; Taghizadeh, G ; Ebrahimi, I ; Taghavi Azar Sharabiani, P ; Mousavi, S. J ; Parnianpour, M ; Sharif University of Technology
Springer Verlag
2018
Abstract
This study aimed to investigate the variability in postural sway patterns during quiet standing in stroke survivors. The postural sway was measured in 19 stroke survivors, as well as 19 healthy demographically matched participants, at 3 levels of postural difficulty (rigid surface with closed and open eyes, and foam surface with closed eyes), and 3 levels of cognitive difficulty (without a cognitive task, easy and difficult cognitive tasks). Both linear analyses (the amount of postural sway variability, including the standard deviation of the COP velocity in both the anteroposterior (AP) and mediolateral (ML) directions), as well as non-linear analyses [the temporal structure of the COP...
Multi-model robust control of depth of hypnosis
, Article Biomedical Signal Processing and Control ; Volume 40 , 2018 , Pages 443-453 ; 17468094 (ISSN) ; Hosseinzadeh, M ; Dumont, G. A ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
This paper presents a multi-model robust control scheme to control the depth of hypnosis during intravenous administration of propofol. The objective of the proposed control scheme is to provide an adequate drug administration regime for propofol to avoid overdosing and underdosing of patients. The proposed scheme is designed to withstand the patient's inherent drug response variability, to achieve good output disturbance and sensor noise rejection, and to attain a good set point response. A comprehensive simulation study of 44 patients is presented to assess the performance of the proposed control scheme. © 2017 Elsevier Ltd
The effects of anxiety and external attentional focus on postural control in patients with Parkinson’s disease
, Article PLoS ONE ; Volume 13, Issue 2 , 2018 ; 19326203 (ISSN) ; Azad, A ; Mehdizadeh, H ; Habibi, S. A ; Mandehgary Najafabadi, M ; Saberi, Z. S ; Rahimzadegan, H ; Moradi, S ; Behzadipour, S ; Parnianpour, M ; Taghizadeh, G ; Khalaf, K ; Sharif University of Technology
Public Library of Science
2018
Abstract
Background Although anxiety is a common non-motor outcome of Parkinson's disease (PD) affecting 40% of patients, little attention has been paid so far to its effects on balance impairment and postural control. Improvement of postural control through focusing on the environment (i.e. external focus) has been reported, but the role of anxiety, as a confounding variable, remains unclear. Objectives This study aimed to investigate the influence of anxiety and attentional focus instruction on the standing postural control of PD patients. Methods Thirty-four patients with PD (17 with high anxiety (HA-PD) and 17 with low anxiety (LA-PD)), as well as 17 gender- and age-matched healthy control...
The effects of dual-tasking on postural control in people with unilateral anterior cruciate ligament injury
, Article Gait and Posture ; Volume 30, Issue 4 , 2009 , Pages 477-481 ; 09666362 (ISSN) ; Hadian, M. R ; Salavati, M ; Mazaheri, M ; Talebian, S ; Jafari, A. H ; Parnianpour, M ; Sharif University of Technology
2009
Abstract
Several studies have investigated postural control in anterior cruciate ligament (ACL) deficient patients; yet the contribution of cognitive processing (attention) in the postural control of these patients is still unclear. A dual-task design was used to determine the effects of a concurrent digit span memory task on standing balance in a group of ACL patients (n = 27) compared with a group of matched, healthy participants (n = 27). In double limb stance, three levels of postural difficulty were studies on a force platform (rigid surface with eyes open, rigid surface with eyes closed, and foam surface with eyes closed). There were three cognitive conditions (no cognitive task, easy cognitive...
Effect of dual-tasking on postural control in subjects with nonspecific low back pain
, Article Spine ; Volume 34, Issue 13 , 2009 , Pages 1415-1421 ; 03622436 (ISSN) ; Mazaheri, M ; Negahban, H ; Ebrahimi, I ; Jafari, A. H ; Kazemnejad, A ; Parnianpour, M ; Sharif University of Technology
2009
Abstract
STUDY DESIGN. Three factors mixed-design with 1 between-subject and 2 within-subject factors. OBJECTIVE. To compare the main effects and interactions of postural and cognitive difficulty on quiet stance between subjects with and without nonspecific low back pain (LBP). SUMMARY OF BACKGROUND DATA. The interference between postural control and cognitive tasks depends on factors such as sensorimotor/cognitive integrity. Changes in peripheral sensory and muscular systems as well as cognitive processes have been observed in LBP patients. It was hypothesized that the effect of cognitive task on postural performance might be different in subjects with nonspecific LBP as compared with healthy...
Effects of lumbosacral orthosis on dynamical structure of center of pressure fluctuations in patients with non-specific chronic low back pain: A randomized controlled trial
, Article Journal of Bodywork and Movement Therapies ; Volume 23, Issue 4 , 2019 , Pages 930-936 ; 13608592 (ISSN) ; Ebrahimi Takamjani, I ; Kamyab, M ; Asgari, M ; Parnianpour, M ; Sharif University of Technology
Churchill Livingstone
2019
Abstract
Background: A few clinical trials have examined the effect of treatment interventions on postural control in patients with chronic low back pain, all of which have exclusively evaluated postural stability using traditional linear measures of postural sway. However, postural control improvement cannot be determined by exclusively relying on linear measurements, because these parameters provide no information on underlying motor control mechanisms. Objective: This study aimed to compare the effect of using lumbosacral orthoses (LSO) together with routine physical therapy, compared to routine physical therapy alone on postural control, using nonlinear analysis techniques. Methods: Forty-four...
Disentangling stability and flexibility degrees in Parkinson's disease using a computational postural control model
, Article Journal of NeuroEngineering and Rehabilitation ; Volume 16, Issue 1 , 2019 ; 17430003 (ISSN) ; Schouten, A. C ; Behzadipour, S ; Taghizadeh, G ; Firoozbakhsh, K ; Sharif University of Technology
BioMed Central Ltd
2019
Abstract
Background: Impaired postural control in Parkinson's disease (PD) seriously compromises life quality. Although balance training improves mobility and postural stability, lack of quantitative studies on the neurophysiological mechanisms of balance training in PD impedes the development of patient-specific therapies. We evaluated the effects of a balance-training program using functional balance and mobility tests, posturography, and a postural control model. Methods: Center-of-pressure (COP) data of 40 PD patients before and after a 12-session balance-training program, and 20 healthy control subjects were recorded in four conditions with two tasks on a rigid surface (R-tasks) and two on foam....
The amount and temporal structure of center of pressure fluctuations during quiet standing in patients with chronic low back pain
, Article Motor Control ; Volume 24, Issue 1 , 2020 , Pages 91-112 ; Ebrahimi Takamjani, I ; Kamyab, M ; Asgari, M ; Parnianpour, M ; Sharif University of Technology
Human Kinetics Publishers Inc
2020
Abstract
The characteristics of postural sway were assessed in quiet standing under three different postural task conditions in 14 patients with nonspecific chronic low back pain and 12 healthy subjects using linear and nonlinear center of pressure parameters. The linear parameters consisted of area, the mean total velocity, sway amplitude, the SD of velocity, and the phase plane portrait. The nonlinear parameters included the Lyapunov exponent, sample entropy, and the correlation dimension. The results showed that the amount of postural sway was higher in the patients with low back pain compared with the healthy subjects. Assessing the nonlinear parameters of the center of pressure showed a lower...
Using robotic mechanical perturbations for enhanced balance assessment
, Article Medical Engineering and Physics ; Volume 83 , 2020 , Pages 7-14 ; Behjat, A ; Torabi, A ; Behzadipour, S ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Balance impairment is critical for many patient groups such as those with neural and musculoskeletal disorders and also the elderly. Accurate and objective assessment of balance performance has led to the development of several indices based on the measurement of the center of pressure. In this study, a robotic device was designed and fabricated to provide controlled and repeatable mechanical perturbations to the standing platform of the user. The device uses servo-controlled actuators and two parallel mechanisms to provide independent rotations in mediolateral and anterior-posterior directions. The device also provides visual feedback of the center of pressure position to the user....
Performance analysis of EEG seizure detection features
, Article Epilepsy Research ; Volume 167 , 2020 ; Mousavi, S. R ; Niknazar, M ; Mardanlou, V ; Coelho, B. N ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Automatic detection of epileptic seizures can serve as a valuable clinical tool which involves a more objective and computationally efficient method for the analysis of EEG data in order to generate increasingly accurate and reliable results. Automatic seizure detection is also an important component of closed-loop responsive cortical stimulation systems. The goal of this study is to evaluate EEG-based features recently proposed for seizure detection to discover the optimum ones for a reliable seizure detection system. We extracted seizure detection features from intracranial EEG signals that were recorded during invasive pre-surgical epilepsy monitoring of people with drug resistant focal...
Preoperative paraspinal neck muscle characteristics predict early onset adjacent segment degeneration in anterior cervical fusion patients: A machine-learning modeling analysis
, Article Journal of Orthopaedic Research ; 2020 ; Harada, G ; Lee, R ; Gandhi, S. D ; Dziedzic, A ; Espinoza Orias, A ; Parnianpour, M ; Louie, P. K. H ; Basques, B ; An, H. S ; Samartzis, D ; Sharif University of Technology
John Wiley and Sons Inc
2020
Abstract
Early onset adjacent segment degeneration (ASD) can be found within six months after anterior cervical discectomy and fusion (ACDF). Deficits in deep paraspinal neck muscles may be related to early onset ASD. This study aimed to determine whether the morphometry of preoperative deep neck muscles (multifidus and semispinalis cervicis) predicted early onset ASD in patients with ACDF. Thirty-two cases of early onset ASD after a two-level ACDF and 30 matched non-ASD cases were identified from a large-scale cohort. The preoperative total cross-sectional area (CSA) of bilateral deep neck muscles and the lean muscle CSAs from C3 to C7 levels were measured manually on T2-weighted magnetic resonance...
Classification of vascular function in upper limb using bilateral photoplethysmographic signals
, Article Physiological Measurement ; Volume 29, Issue 3 , 2008 , Pages 365-374 ; 09673334 (ISSN) ; Zahedi, E ; Jajai, H. M ; Sharif University of Technology
2008
Abstract
Bilateral PPG signals have been used for comparative study of two groups of healthy (free from any cardiovascular risk factors) and diabetic (as cardiovascular disease risk group) subjects in the age-matched range 40-50 years. The peripheral blood pulsations were recorded simultaneously from right and left index fingers for 90 s. Pulses have been modeled with the ARX440 model in the interval of 300 sample points with 100 sample points overlap between segments. Model parameters of three segments based on the highest fitness (higher than 80%) of modeled segments were retained for each subject. Subsequently, principal component analysis (PCA) was applied to the parameters of retained segments...
Expression of apoptosome-related genes in periodontitis
, Article Gene Reports ; Volume 23 , 2021 ; 24520144 (ISSN) ; Badrlou, E ; Nazer, N ; Sadeghi, G ; Kiani Haftlang, M ; Mirzajani, S ; Shadnoush, M ; Sayad, A ; Ghafouri Fard, S ; Sharif University of Technology
Elsevier Inc
2021
Abstract
Recent studies have provided clues for participation of apoptosis related genes in the development of periodontitis. We examined expression of four apoptosome related genes namely CPSF7, AGO2, WDR33 and HUR1 in the blood and tissues of patients with stage III-IV periodontitis compared with control blood/tissue samples. Expression of AGO2 was significantly higher in the blood specimens of individual having periodontitis compared with healthy persons (ratio of mean expression = 6.9, P value = 4.79E−02). However, when categorizing individuals based on their gender, none of comparisons yielded significant results. Expression of AGO2 was not different between tissue samples of patients and...
Altered expression of STAT genes in periodontitis
, Article Human Antibodies ; Volume 29, Issue 3 , 2021 , Pages 209-216 ; 10932607 (ISSN) ; Movafagh, A ; Badrlou, E ; Nazer, N ; Yari, M ; Sadeghi, G ; Mirzajani, S ; Shadnoush, M ; Sayad, A ; Ghafouri Fard, S ; Sharif University of Technology
IOS Press BV
2021
Abstract
Signal Transducer and Activator of Transcription (STAT) pathway is functionally located downstream of Janus kinases proteins and can integrate signals from diverse pathways, thus regulating several aspects of immune responses. Although contribution of STAT proteins in the pathogenesis of several inflammatory conditions has been confirmed, their role in the development of periodontitis has been less appraised. Thus, we assessed levels of STAT transcripts in the periodontal tissues and circulation of affected individuals compared with the corresponding controls. Expression of STAT1 was remarkably lower in tissues samples of patients compared with control tissues (Ratio of mean expression (RME)...
Biomechanical analysis of the pelvis angular excursion in sagittal plane in response to asymmetric leg loading tasks in females with and without nonspecific chronic low back pain
, Article Journal of Biomedical Physics and Engineering ; Volume 11, Issue 3 , 2021 , Pages 367-376 ; 22517200 (ISSN) ; Kamali, F ; Parni Anpour, M ; Davoudi, M ; Sharif University of Technology
Shriaz University of Medical Sciences
2021
Abstract
Background: Controlling pelvic excursions is the focus of stabilization exercises such as legs loading tasks in rehabilitation of non-specific chronic low back pain (NSCLBP) patients. Progression of these exercises is based on the ability to perform tasks with minimal sagittal pelvic excursions. In spite of emphasis on minimizing pelvic motions, no previous studies have investigated kinematic analysis of the pelvic excursions during leg loading exercises in NSCLBP patients. Objective: This study aims to investigate the sagittal pelvis excursion during performing asymmetric leg loading tasks in individuals with and without NSCLBP. Material and Methods: In this cross-sectional study, kinematic...