The aim of this investigation is to compare the effect of applying two transcutaneous electrical nerve stimulation (TENS) current with different frequencies (2 Hz & 100 Hz) on Hoffmann reflex recorded from gastrosoleus muscle of healthy people. Forty female subjects between 20 to 30 years of age were participated in this quasi-experimental design. Twenty of them were exposed to the 100 Hz current and the remaining 20 to 2 Hz current on dermatome S1 root. The excitability of the alpha motoneurone was measured by H-reflex amplitude (peak to peak max/2) before and after the application of the TENS current for 30 minutes. The reflex was recorded and at measured before (TO) and after the application of TENS at different times (T1, T% and T10) up to 10 minutes. The mean values were compared by multiple paired T test (alpha=0.00825). The results indicate a considerable decrement in Hoffmann reflex amplitude after application of 100 Hz current in comarison with that of before the application. The effect last for 10 minutes after the TENS application, whereas the application of 2 Hz current results in increment of the Hoffmann reflex amplitude. The 5 and 10 minutes interval test dose not show any significance and the results were attenuated befor 5 minutes. As a conclusion high frequency of TENS (100 Hz) has an inhibitory effect on excitability of alpha motor neurone reflex lasting for 10 minutes, while low frequency of TENS (2 Hz) has an facilatory effect on the same motoneurone with short lasting effect.
The aim of this investigation is to compare the effect of applying two transcutaneous electrical nerve stimulation (TENS) current with different frequencies (2 Hz & 100 Hz) on Hoffmann reflex recorded from gastrosoleus muscle of healthy people. Forty female subjects between 20 to 30 years of age were participated in this quasi-experimental design. Twenty of them were exposed to the 100 Hz current and the remaining 20 to 2 Hz current on dermatome S1 root. The excitability of the alpha motoneurone was measured by H-reflex amplitude (peak to peak max/2) before and after the application of the TENS current for 30 minutes. The reflex was recorded and at measured before (TO) and after the application of TENS at different times (T1, T% and T10) up to 10 minutes. The mean values were compared by multiple paired T test (alpha=0.00825). The results indicate a considerable decrement in Hoffmann reflex amplitude after application of 100 Hz current in comarison with that of before the application. The effect last for 10 minutes after the TENS application, whereas the application of 2 Hz current results in increment of the Hoffmann reflex amplitude. The 5 and 10 minutes interval test dose not show any significance and the results were attenuated befor 5 minutes. As a conclusion high frequency of TENS (100 Hz) has an inhibitory effect on excitability of alpha motor neurone reflex lasting for 10 minutes, while low frequency of TENS (2 Hz) has an facilatory effect on the same motoneurone with short lasting effect.
Introduction: It is suggested that quadriceps muscle has an important role in stability & mobility of Knee joint in athletics and normal individuals therefore, the purpose of this study was evaluation of the strength in Power Athletics (PA) and Normal Un-trained Individuals (NUI) groups.
Methods and Materials: 31 Females (20 NUI & 11 PA) participated in this study. For measuring the strength, each individual performed 5 continuous concentric-eccentric maximal contraction at angular velocities of 90°/s, 135°/s. Twenty five percent of each individual (Maximum Voluntary Isometric Contraction) MVIC was determined and used as Pre-load force.
Results: Averages concentric & eccentric torques were greater in PA group in comparison with NUI group. The significant difference (P<0.02) existed between PA and NUI groups. Average concentric torques of quadriceps muscle decreased (with increasing of speed from 90°/s to 135°/s) and average eccentric torques increased. Average eccentric torques were greater (P<0.01) in PA & NUI groups in comparison with average concentric torques.
Conclusion: PA group strength was greater in comparison with NUI group. This is possibly due to the type of muscle fibers in this group have (greater type II fibers). Accordingly, it is critical to consider the role of eccentric exercise in PA group for preventing sport injury.
Background: Graft-versus-host disease is one of the major complications after allogenic bone marrow transplantation, but it is not easy to anticipate the onset. Cytokines released by type 1 T-helper cells are thought to play a pivotal role in acute graft-versus-host disease (aGVHD). The ability to predict the likely occurrence of graft-versus-host-disease (GVHD) after BMT would be extremely valuable. By serially measuring serum levels of soluble IL-2 receptor (sIL-2R), IL-18 and following allogeneic bone marrow transplantation (BMT), we tried to define their relationship to aGVHD as complication of the transplantation and determine useful markers for aGVHD predictors.
Materials and Methods: Serum sIL-2R, IL-18, and levels were measured by sandwich ELISA in 219 sera samples from 39 patients (with hematological disorders before and after allogeneic BMT) and 28 controls. All patients received BMT from HLA-identical siblings.
Results: 25 patients developed aGVHD and serum levels of sIL-2 R and IL-18 , in sera drawn before transplantation , in patients with acute graft-versus-host disease (aGVHD +) , were increased in comparison of patients without acute graft-versus-host disease (aGVHD ¯) and control group and there wasn’t any significant differences in serum levels of sIL-2 R and IL-18 in aGVHD ¯ patients and controls. Serum level of IL-18, in aGVHD+ patients, was increased during day 3 - 24 after BMT, and there was a significant difference in patients with GVHD 0 – GVHD III. In majority of patients with acute GVHD (60 %) , the peak levels of IL-18 and IL-2R was achieved on day 10 after BMT and the rise in sIL-2R and IL-18 preceded of clinical signs of GVHD (mean day 15 after BMT). Level of IL-18 in patients with aGVHD had strongly correlated with the severity of aGVHD on Day 10 after BMT. IL-18 level mean (before BMT), in patients who received Busulfan and Fludarabin to treat aGVHD, was lower than in patients who received Busulfan - Endoxan, or Cyclophosphamide.
Conclusion: Our data concluded that IL-18 plays an important role in the development of aGVHD and IL-18 level might be an indicator for aGVHD, reflecting the severity of the disease. These findings suggest that IL-18 may play important roles in the pathogenesis of aGVHD and that measurement of serum IL-18 levels can be useful predictor of aGVHD.
Background: One of the most important concerns in orthopedic medicine is the low back. Considering the importance of muscle function in preventing LBT by controlling too much load and stress applied on the spinal joints and ligaments.
Materials and Methods: The aim of this research was to determine the timing and level of activities of lumbopelvic muscles in response to postural perturbations caused by unexpected loading of the upper limbs in standing on three different supporting surfaces (neutral, positive slope, negative slope) in 20 healthy females 18 to 30 years old ( = 23.20 SD = 2.55 ). The electromyographic signals were recorded from the deltoid, gluteus maximus, internal oblique abdominis and lumbar paraspinal muscles of the dominant side of the body to evaluate the onset time, end time, level of muscle activity (RMS) and duration of different muscles in one task and one muscle in different tasks.
Results: The results showed that the agonists (posterior muscles) activated at first to compensate the flexor torque caused by loading and then the antagonists (anterior muscles) switched-on to compensate the reaction forces caused by agonist activities. With regards to continuous activity of internal oblique and its attachments via thoracalumbar fascia to the transverse processes of the lumbar vertebrae, it can be considered as one of the major stabilizer muscles of the trunk .
Conclusion: Finally the results indicated that supporting surface type didn’t have any effect on timing and scaling of muscle activities in different tasks suggesting that probably spinal and trunk priprioceptors are just responsible for triggering postural responses and they don’t have any role in determining timing and scaling.
Background: Low back pain (LBP) is a one of the most common symptoms of vertebral column diseases. Spinal muscles have a outstanding role in maintaining vertebral column function in daily life. But proper function and motion of hip and knee joints also has an important role in performing smooth, fine and nonstressed movements of lumbar spin. Where as accurate and fine motions of hip and knee joints in cooperate with lumbar spin can improve translation and summation of forces and increase performance of movements. The aim of this research is to indicate the amount of interventions of lower limb joints on lumbar spin function in patients with LBP, and attention to physical treatment (PT) of them.
Materials and Methods: Fifty females with LBP due to osteoarthritis ( OA) of lumbar spin participated in this study and divided in two groups randomly with similar number of cases: a) ordinary treatment or control group and b) complementary treatment group. Patients in control group treated by routine PT approach ( superficial heat, ultrasound, TENS, forward flexion and back extension exercises ) and patients in complementary or test group received routine treatment similar to control group and also strength and stretching exercises of hip and knee joint muscles ( latisimous dorsi, gluteous maximus, iliopsoas, quadriceps and hamstring ) bilaterally. Range of motion (ROM) of lumbar, hip and keen joints by valid goniametere and pain of lumbar in motions at all of axis by visual analog scale measured before, after five and ten sessions of treatments in both groups.
Results: In control group with non parametric tests there was not significant difference of MMT of muscles and ROMs of hip and knee joints. Lumbar pain in motion after ten sessions of PT in this group reduced significantly ( P< 0.05 ). Increase of lumbar motion in all of axis after PT was significant at this patients ( P< 0.05 ). In second group that received complementary treatments ROM of joints, lumbar pain had significant differences between onset of treatments and five and ten sessions later ( P< 0.05 ), but there was not significant findings in MMT of muscles. There were significant differences between percentages of reduce of pain and increase of ROM in comparison of two groups ( P< 0.05 ). Where as patients that received ordinary PT and strength and stretching of muscles around of hip and knee indicated better recovery signs.
Conclusion: Reduce of lumbar pain with improve of motion and flexibility of muscles such as quadriceps, hamstring, gluteus maximus, iliopsoas and latisimous dorsi in a complete physical therapy approach indicate there are a great correlation between lumbar pain and functionality of lower limb joints. Therefore concentration to flexibility and extensibility of muscles of lower limbs is a basis aim in treatment of patients with lumbar OA.
Background: Joint trauma and injury are the most common causes of dynamic instability. Dynamic instability has a great effect on the lumbar spine, due to its three-dimensional motions. The greatest amounts of compression and shearing force are imposed at the points of maximum torque and velocity. The changes in these phase angles upon bearing various loads can cause some pathologic conditions. In this study, we examined the phase angle at maximum torque and velocity in the three planes of movement and then estimated their displacement upon external loads.
Methods: Using the B200 isoinertial dynamometer, 13 subjects were tested in three stages as follows: 1) Familiarization with tests and apparatus. 2) Warm-up and three maximum isometric tests, with a rest interval between each test, in the three axes of lumbar motion including: flexion/extension, rotation to right/left, lateral flexion to the right/left. 3) Five dynamic tests in these three axes of motion without load, with 25% maximum voluntary torque, and with 50% maximum voluntary torque. Special software was used to analyze the raw data and detect the occurrence of maximum torque and velocity in the dynamic range of motion at each of the three axes.
Results: When the load was increased, the maximum dynamic torque in each of the three axes increased (P<0.05). The increase in load shifted the phase angles toward the maximum torque and velocity (P<0.05), with a positive correlation between changes in torque and velocity phase angles (P<0.05).
Conclusions: Rather than being a function of the biomechanical pattern, the changes in maximum torque and velocity of the phase angles following an increase in motion resistance to the outer range of the three axes are actually a control behavior in the motion processing system in dynamic movement.
Background: The long-term effects of poliomyelitis are known in many of countries. In despite of one accrue title for these signs and symptoms there are similarity aspects in patients' problems. In the signs of explained, absence of strength and endurance, musculoskeletal difficulties, respiratory dysfunction, sleep disorders are more generalized. Prevalence of post polio syndrome (PPS) is aim of this study.
Methods: 150 subjects with history of poliomyelitis (80 male and 70 female) in Tehran city contributes in this study and complete question forms.
Results: Muscle pain was reported in 88% of subjects. Thigh muscle weakness was at 42/28%, also muscle spasm indicated at 66%. Recurrent falling of subjects appeared in 74/7%. Early fatigue reported 86%. Above five signs selected for PPS. In this study 85 subjects had four signs of above criteria or 56.66% of subjects had PPS.
Conclusion: Depended of evaluation and observation there is post polio syndrome in Tehran. Recommended for physical therapy of post polio syndrome attend to stages of progression of this syndrome. In aim to this procedure, physical treatment of these patients must limit to muscle fatigue and also severe physical and exercise activities must be reduce, also some mild aerobic activities without fatigue can be useful.
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MicrosoftInternetExplorer4
Background: Muscle
weakness and fatigue are two factors that cause muscle injuries. The roll of
motor control is important in regulation and reduction of this effect.
Repetition of motion after muscle fatigue is due to the significant role of
motor control system. The aim of this study was to evaluate the quality of roll
control of central nervous system following fatigue in order to answer primary
questions in therapeutic exercises.
Methods: Twenty voluntary healthy subjects
participated in this study. Dominant abductor policis brevis after surface
electromyography (SEMG) of maximal voluntary contraction
(MVC) fatigued by maximum three
minutes isometric contraction in specific hand splint monitored by dynamometer
until reduction of activities to 50% MVC. Before and immediately after
fatigue test, 5 dynamic full range of motion in
abduction direction performed without resistance and muscle activities recorded
by SEMG. Three middle muscle activities
selected for comparison of Symmetrical Index (SI) as specificity of motor control assessment. Fatigue
indicators were percentage of reduction of MVC and median and mean frequency of power spectrum of MVC before and after fatigue test.
Results: Significant
reduction of MVC (46.77%), median (13.03%) and
mean (12.20%) frequency were showed (p=0.001),
whereas significant increase of SI (10.76%) appeared (p=0.000),
following fatigue test.
Conclusion: Fatigue reduces muscle
contraction velocity, therefore median and mean frequency decrease. Also after
muscle fatigue reduces of muscle proprioception sense appears, that can cause
slow dynamic joint motion. Upper central control systems try to correct this
situation by involving new motor units and changes of muscle timing.
Synchronization of primary and new motor units plays an important role in
increase of SI.
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MicrosoftInternetExplorer4
Background: Placenta accreta is a life-threatening complication after previous cesarean
delivery. The aim of this case report is to present a case of placenta percreta
with bladder involvement and subsequent maternal death.
Case
presentation: The patient was a 37-year
old who had an unwanted pregnancy due to tubectomy failure two years afterwards.
She was hospitalized at 26th and 30th week of gestation
because of gross hematuria. Sonography reported placenta previa. Cesarean section
was performed at 34th gestational week. Due to severe hemorrhage, hysterectomy with resection of some
part of the bladder was done. Died at the operating room after four hours of
severe uncontrollable hemorrhage.
Conclusion: The increasing prevalence of different forms of placenta accreta is the result
of the ever-increasing rate of cesarean deliveries. One of the strategies to
prevent this catastrophic obstetric complication is decreasing the number of cesarean
deliveries without appropriate indications.
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