Tehran University Medical Journal

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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.

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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.

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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.

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Background: The purpose of this study was to measure isokinetic maximum and average peak torque of internal and external rotators of glenohumeral joint in volley ball and tennis players
Methods: This study was performed on 17 professional female athletes (7 tennis players &10 volleyball players) with age ranged 18-28 years. The subjects had played in a skilled team for more than 3 years. They were free from injury to their dominant shoulder in the past year. Subjects performed a five minute warm up by shoulder wheel and Maximum average Peak Torque (APT) were obtained unilaterally by a Biodex System 3 with the arm of players in 90 degree abduction at 120,180 & 210 o/s. Players performed five trails of concentric movements with 30 second rest between them.
Results: Maximum and average of maximum torques of shoulder rotator, in both groups, expect for internal rotators of tennis players, reduced by increase of movement speed (P<0.05). There are not significant difference between two groups in maximum, average of maximum torques and normalized data (ratio of maximum torque to weight). There is significant difference between two groups in percentage of APT of External rotator / Internal rotator ratio at 210 o/s (P<0.05).
Conclusion: Volleyball and tennis have no effect on isokinetic strength of shoulder rotators. In high speed, ratio of External rotator / Internal rotator is reduced. This indicates that increase in movement speed increase internal rotator in comparison to external rotator in these professional female athletes.

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Background: Both isokinetic testing and functional tests are commonly used to evaluate anterior cruciate ligament reconstructed (ACLR) patients. The object of this study was to evaluate motor performance of the knee and determine the relationship of isokinetic test scores to scores on a variety of lower extremity functional tests.
Methods: Ten healthy subjects and eleven ACLR patients at least six months after surgery performed the following: knee isokinetic tests at 60 and 180 deg/sec three functional tests including leg vertical jump, single hop, and triple cross-over hop for distance. The International Knee Document Committee Subjective Knee Evaluation Form (IKDCSKEF) was used to score the self-assessment of each study participant. Paired T-test was used to compare the involved and uninvolved knee. Pearson correlation coefficients were used to determine the relationship between the scores on the isokinetic test and functional tests. Significance was determined by P<0.05.
Results: IKDCSKEF score was significantly lower in patients than control subjects. Quadriceps peak torque and functional test scores were significantly lower in the involved knee of the ACLR subjects compared to the uninvolved knee. Correlation coefficients of isokinetic peak torque to body weight and functional testing were not significant in patients or control subjects, whi1e the limb symmetry index (LSI) of the quadriceps isokinetics peak torque to body weight and the LSI of the functional tests were significant (r = 0.54 to 0.97).
Conclusion: These results indicate a significant relationship between the LSI of various functional tests and the LSI of isokinetic testing among ACLR patients. Thus, in situations where an isokinetic dynamometer is not available, the LSI of functional tests can be used to estimate quadriceps deficiency for ACLR patients.

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Background: The changes in motor control after the use of a supportive belt can contribute to the understanding of its effects on performance. The aim of this study is to quantify motion pattern values relative to the spinal column during the use of a lumbosacral belt.
Methods: For fifty healthy female volunteers, the range of motion, maximum isometric torque and changes of phase angle of maximum torque and velocity in two positions, standing and sitting, in two directions, flexion and extension, following the use of a lumbosacral belt were measured using an isoinertial dynamometer (Isostation B200) and compared.
Results: Range of motion in both directions in both positions was reduced significantly (P<0.05). Significant reduction of maximum isometric torque was observed in flexion while sitting and in extension while standing and sitting (P<0.05). Phase angle of maximum torque and velocity also changed significantly in both directions and both positions (P<0.05).
Conclusion: The lumbosacral belt can act in different ways to prevent injury. It reduces the forces applied to lumbar vertebra and, by changing the maximum torque and velocity phase angles at the onset of range of motion, provides greater stability for joints. Furthermore, the belt can reduce stress imposed on the posterior joints of the spine and limits several momentary forces at the onset of joint movement. Under these conditions, joint injuries can be reduced and prevent some of the mechanical stress that causes lumbar joint disease.

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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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Normal 0 false false false EN-US X-NONE AR-SA 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.