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Backgroung and aim: Neck pain is one of three common complains of neuromuscular system. There are three subsystem to maintain stability of spine: passive subsystem, active (muscles) subsystem and control subsystem. Detection of postural muscle response during postural perturbation like fast arm movement can be utilized to analyse of postural control. Wearing cervical collars is a way to prevent or cure cervical pain. The aim of the present study was to investigate the effect of soft cervical collar on movement response and duration of activity and recruitment pattern of cervical muscles. 

Materials and methods: Twenty healthy young women participated in this study. They flex right shoulder in response to sound stimulus with and without wearing soft cervical collar. Surface Electromyography (EMG) used to assess postural muscle activity in following muscles: Deltoid , Trapezius , Cervical Erector spinae and  Sternocleidomastoid. The effect of soft cervical collar on reaction time, onset and duration of activity of cervical muscles was calculated.

Results: Wearing soft cervical collar increased reaction time of arm flexion  (P< 0.05) and decreased duration of activity of cervical extensor, trapezius and erector spinae (P< 0.05). During shoulder flexion with additional load, onset activity of trapezius muscle was significantly earlier than other neck muscles but cervical erector spinae and sternocleidomastoid exhibit coactivation pattern in response to perturbation .

Conclusion: During fast arm movement that leads to postural perturbation, soft cervical collar alleviates the response and reduce activity of muscles. The strategy of motor control centers in response to perturbation in cervical spine is coactivation of flexor and extensor muscles to maintain stability. 

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Background and Aim: Muscle fatigue is a factor that caused muscle injuries. Ability to perform movement without error and controllability has important role in reduction of injuries. Reproduce ability of motion is reduced after muscle fatigue. Evaluation of motor control can produce suitable conditions for assessment of these changes and help us treatment guide lines for prevention of injuries. The aim of this study was to evaluate motor control changes following onset of fatigue in patients with anterior knee pain as a physiological aspect.
Materials and Methods: Fifteen voluntary female (10 healthy, 5 patients with bilateral syndromes) participated in this study. During dynamic fatigue test (open and closed chain movements), muscle activities were recorded from bilateral vastus medialis, vastus lateralis and rectus femoris (20 healthy and 10 patients quadriceps muscles) by surface electromyography (sEMG). Five dynamic cycles of motions were selected before and immediately after fatigue and then average of three middle cycles were compared for Symmetry Index (SI) as motor control assessment.  Also Median Frequency (MDF) were computed as an indicator for onset of fatigue. 
Results: MDF reduced significantly in both groups. This reduction was markedly showed in patients group. Reduction of SI was significant after fatigue test. Comparison of SI between groups indicated that before fatigue there was significant difference but after fatigue test was not significant.  
Conclusion: Dynamic motions can produce muscle fatigue and reduction of MDF. High central control system used different synergies following pain and functional impairment. Synergy patterns change after dynamic motions fatigue and cause reduction of SI. This change is dependent to pain and functional impairment and has not a stable pattern. 

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Background and Aim: Patellofemoral pain syndrome (PFPS) is a common musculoskeletal condition. Women with patellofemoral pain syndrome would present significant weakness in many of hip muscle groups when compared with the healthy group. The objective of the present study was to compare the strength of hip abductor, extensor and external rotator muscle groups in sedentary women with bilateral patellofemoral pain syndrome to a matched control group of sedentary women without patellofemoral pain syndrome. 

Materials and Methods: Twelve women with bilateral patellofemoral pain syndrome as experimental group and other twelve matched women as control group participated in this study. Maximum isometric strength for three hip muscles including abductor, extensor and external rotator muscle groups was measured bilaterally in all subjects using a dynamometer fixed on a platform and finally averaged between two limbs and compared with the control group.

Results: The hip abductor, extensor and external rotator muscle groups of experimental group were statistically weaker than that of the control group (p< 0.001).

Conclusion:  It seems that lower limb muscles including hip muscles of women with patellofemoral pain syndrome become weaker due to disuse conditions. 

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Background and Aim: Given the biomechanical differences between over ground and treadmill walking, it is expected that the contraction of muscles should be also different, so exercise training in these scenarios may have various effects on trunk muscles. The aim of this study was to compare amplitude and duration of activation of trunk muscles during over ground and treadmill walking to prescribe a suitable exercise mode considering the special circumstances of each person.

Materials and Methods: Nineteen healthy 20-40 years old male with sedentary life style were selected via simple sampling. Surface electromyography of rectus abdominis, external oblique, longissimus and multifidus muscles were recorded.

 Results: In each gait cycle, there was not statistically significant differences on duration of trunk muscles activity between treadmill and over ground walking. The mean amplitude of these muscles was greater on treadmill in comparison with over ground and this difference was statistically significant for rectus abdominis (P=0.005), longissimus (P=0.018) and multifidus (P=0.044) muscles.

Conclusion: Stabilizing role of trunk muscles during walking causes them to be active throughout the entire gait cycle. The increased muscle amplitude on treadmill might show that more motor units may be recruited during the contraction, which is helpful in prescribing the appropriate type of exercise especially to patients who have trunk muscles weakness. 

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Background and Aim: Given the biomechanical differences between over ground and treadmill walking, it is expected that the contraction of muscles should be also different, so exercise training in these scenarios may have various effects on trunk muscles. The aim of this study was to compare amplitude and duration of activation of trunk muscles during over ground and treadmill walking to prescribe a suitable exercise mode considering the special circumstances of each person. 

Materials and Methods: Nineteen healthy 20-40 years old male with sedentary life style were selected via simple sampling. Surface electromyography of rectus abdominis, external oblique, longissimus and multifidus muscles were recorded.

Results: In each gait cycle, there was not statistically significant differences on duration of trunk muscles activity between treadmill and over ground walking. The mean amplitude of these muscles was greater on treadmill in comparison with over ground and this difference was statistically significant for rectus abdominis (P=0.005), longissimus (P=0.018) and multifidus (P=0.044) muscles.

Conclusion: Stabilizing role of trunk muscles during walking causes them to be active throughout the entire gait cycle. The increased muscle amplitude on treadmill might show that more motor units may be recruited during the contraction, which is helpful in prescribing the appropriate type of exercise especially to patients who have trunk muscles weakness.  

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Background and Aim: Neck pain is one of the most common musculoskeletal disorders in industrial society. There are complex changes in motor control of cervical spine in neck pain patients. The aim of this study was to compare the latency of activation of neck muscles during upper limb movement between neck pain patients and healthy subjects.

Materials and Methods: Eighteen chronic non-specific neck pain patients and eighteen healthy subjects who were matched in age, weight and height participated in this study. Subjects were standing on the ground and performed flexion and abduction movement of the right arm until at least 90 degree in five trials and consequently surface electromyography of neck muscles was recorded. Activation time of neck muscles was determined in comparison with the activation time of deltoid muscle (as an event) and then compared between two groups.  

Results: Findings of this study showed that in patients with chronic neck pain and healthy subjects during upper limb flexion and abduction movements, the superficial neck muscles were activated after deltoid activation. As well as in the neck pain patients compared to the healthy subjects superficial neck muscles onset was significantly appeared with delayed (P<0.05).

Conclusion: In patients with neck pain compared to healthy controls, the neck muscles were significantly delayed in responses to the internal perturbations of fast upper limb movements. It may be to increase the risk of injuries of neck region during fast upper limb movements.

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Background and Aim: This study was performed to compare the stiffness of hamstring and rectus femoris muscles in subjects with anterior knee pain and normal subjects.

Materials and Methods: In this non experimental and case-control study, 20 persons with anterior knee pain were selected simply from convenient sample and 20 healthy persons were selected by matching method. proximal and distal stiffness of hamstring and rectus femoris muscles were measured using an isokinetic device in the passive mode. Also, maximal concentric peak torque during flexion and extension movements of hip and knee, in two groups were compared by independent T-test and correlation analysis.

Results: There was no significant difference between anterior knee pain and proximal compartment of rectus femoris(P=0.320) and hamstring(P=0.125) stiffness, but there was significant difference between anterior knee pain and distal compartment of rectus femoris and hamstring stiffness (P<0.001). Significant relationship was found between anterior knee pain and muscles strength (P<0.001). No correlation was found between strength and stiffness of rectus femoris (P=0.356) and hamstring muscles (P=0.643) in patients group, but in healthy subjects this relationship was found (P<0.001). 

Conclusion: In patients with anterior knee pain, hamstring and rectus femoris muscles stiffness increased and muscle strength decreased. Increasing of muscle strength was effective on stiffness in healthy subjects, but there was no relation between them in patients group. Also rectus femoris and hamstring muscles possibly have different proximal and distal neuromuscular compartments.

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Background and Aim: Multifidus muscle is one of the short and deep posterior Paraspinal muscles, which gives stability to the spine during various activities. Studies have shown that in people with neck pain, weakness and atrophy of neck muscles are major factors in the incidence of neck pain. Measurement of muscle's dimensions by ultrasonography provides an opportunity to be able to objectively assess muscle atrophy or hypertrophy. This study aimed to assess symmetry of cervical multifidus muscle size in females with chronic non-specific neck pain and healthy by ultrasonography apparatus.

Materials & Methods: Twenty five women with unilateral chronic nonspecific neck pain and 25 healthy women were participated in this study. All subjects were employed and more than 4 hours working with computers or paying office in a day. Imaging of the cervical multifidus muscles were done bilaterally in the level of the fourth vertebra. Anterior-Posterior Dimension(APD), Lateral Dimension(LD), Cross-Sectional Area (multiplied of two diameters(APD&LD)) and the Shape ratio (Lateral diameter divided by the Anterior-Posterior diameter(LD/APD)) of the muscle were measured and recorded. 

Results: Multifidus muscle size in patients group was smaller than the healthy group. In patients group, size of multifidus muscle in the painful side was smaller than the opposite side. Asymmetry of muscle size between the two sides, in the patient group was higher than the control group (P < 0.05). The ratio of smaller size to the larger size of the muscle, in the healthy group was higher than the ratio in the patient group (P < 0.05).

Conclusion: In patients group, asymmetry of the muscle size between two sides, also smaller size of the muscle in the painful side, showed that muscle atrophy has happened in the involved side.

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Background and Aim: One of the risk factors in sports injuries is inappropriate flexibility of muscles, which leads to pain, decrease range of motion and functional limitation in sport or daily activities and affects the athletes’ quality of life. The aim of this study was to investigate the relationship between flexibility of calf muscles and functional status of athletes with ankle injuries.
Materials and Methods: Thirty male athletes with ankle injuries (mean age ± SD, 22.63 ± 3.94 range: 18-40 years) participated in this study. Ankle dorsiflexion of affected and non-affected sides were measured with a goniometer. FAOS (Foot and Ankle Outcome Score) questionnaire was used to evaluate the functional status of ankle.
Results: The relationship between flexibility of calf muscles in the affected extremity, and total score of the functional questionnaire, was not statistically significant (P>0.05). While the relationship between the flexibility of muscles and functional questionnaire's total score in the non injured extremity was significant (P = 0.004, r = 0.51).
Conclusion: This study revealed that although the athletes who have more flexibility of calf muscles, show better functional status of ankle but there is not necessarily a relationship between inflexibility of the muscles and lowered functional status.

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  Background and Aim: Since many of people in their functional activities mostly place their knee joint in flexed position, the hamstring muscles tend to be shortened. On the other hand, shortness of these muscles affect the knee joint directly and the ankle and hip joints indirectly. It predisposes the individual to musculo-skeletal injuries. Thus, by early diagnosing and treatment of it, the tension may be decreased, the relaxation increased and the development of injuries can be prevented. In order to achieve this goal, various stretching techniques are used. The purpose of this study is to compare the effects of static and PNF stretching on shortness of hamstring muscles in 18-30 years young women.

  

  Materials and Methods: Thirty 18-30 years old nonathletic women without any history of pathology in hip, knee or back were selected. They were divided into three groups with 10 women in each group(static stretch, PNF stretch and control). The two stretch groups were received stretching program five days every week for three weeks, while the control group was not.

  Results: The range of knee extension of both groups of static and PNF stretching increased (p<0/05). However there was no significant difference between these two groups (p>0/05).

  

  Conclusion: Employing of both methods (static and PNF stretching) increase the hamstring muscles flexibility. However there was no significant difference between two groups in increasing rang of knee extension.

  

  Key words: Hamstring muscles, static stretching, PNF stretching

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Background and Aim: Sacroiliac joint (SIJ) is one of the most important elements in normal musculoskeletal function during gait cycle and serve as a shock absorber during heel strike and load transfer from lower limbs to trunk. Its stabilizing is the product of osseous, ligamentus and muscular elements which muscle activity of these muscles (Gluteus Maximus, Biceps Femoris, Multifidus, Erector Spinea, and Latissimus Dorsi) is important in load transfer through SIJ. It seems that the function of the given muscles in sacroiliac joint pain subjects is interrupted. So, the aim of the present study is to compare muscle activity during different events of stance phase of gait cycle during preferred and slow speed between sacroiliac joint pain and healthy subjects.

  

Methods and Materials: Thirteen SIJ pain subjects (12 females, 1 male) and thirteen healthy subjects (11 females, 2 male) participated in this study. Muscle activity based on RMS from selected muscles was recorded during different events of stance phase of gait either preferred or slow speed by EMG Data-link Biometrics and normalized according to muscle activity during a 500 ms period in rest position before starting walking called Baseline Correction.

  

Results: Significant statistical differences were found between two groups in muscle activity based RMS during different events of stance (p=0/006), but there was no significant difference in effect of speed on RMS between two groups (p=0/37). Significant Statistical differences were also seen between selected muscles in each group separately during slow speed of walking (p=0/003) but no significant statistical difference during preferred speed in SIJ pain group (p=0/14).

  

Conclusion: SIJ subjects have showed increased levels of muscle activity during different events of stance phase of gait with preferred and slow speeds. These increased levels can be interpreted as a mechanism to control trunk movements effectively, provide sufficient support and transfer load to lumbar area efficiently.

  

Key words: Muscle activity, Sacroiliac joint, Gait, Trunk muscle, Lower limb muscles

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Background and Aim: The normal response of H-reflex depression (HD) was reduced in chronic spinal cord injury (SCI) patients. The reduction of this normal response can lead to increase the muscle tone and spasticity. The purpose of this study is to investigate the effect of tripolar cathodal stimulation on HD in SCI patients.

 

Materials and Methods: This study was conducted in 10 volunteered SCI patients and 13 healthy male and female aged 28.91 ± 5.78 years. H-reflexes were elicited at 0.2, 5 and 0.2 Hz and intensity of 65-70 percent of the maximum H-reflex amplitude, before and after tripolar cathodal electrical stimulation of the spinal cord at T₁₁ level.

 

Results : Before trioplar stimulation, H-reflex amplitude decreased with increasing stimulation frequency only in healthy group. H-reflex amplitude decreased from 2.60 ± 1.48 to 1.34 ± 1.30 by 5Hz frequency (P=0.000). After trioplar stimulation in SCI patients group, HD increased with increasing stimulation frequency and H-reflex amplitude decreased significantly from 2.21 ± 1.98 by 0.2 Hz frequency to 1.29 ± 1.50 by 5Hz frequency(P=0.014).

Conclusion: Application of one session of cathodal trioplar stimulation can result the returning of normal HD in SCI patients. Cathodal trioplar stimulation is a non-invasive, without side effects, and an inexpensive method that may be a valuable tool to return the normal inhibition and modulating behavior of the spinal cord circuits.

  

Keywords: Spinal cord injury , Tripolar stimulation, H-reflex depression, Soleus muscle

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Background and Aim: Genu varum and genu valgum are two most common deformities of the knee joint in children and adults. In these deformities knee muscles function maybe affected by the alteration in mechanical axis of lower limb. The aim of this survey was to provide some basic knowledge about the function of knee muscles in patients with genu varum and genu valgum deformities.

  

Materials and Methods: Studies were identified by searching in the Pub-Med, Science Direct, Google Scholar databases and authoritative references available on the internet and library for articles and books published after 1990,with the key words such as genu varum, genu valgum, knee muscles, bow leg, knock knee and knee frontal angle.

  

Results: Among 102 papers and 10 books resulted from the first search, only 30 papers and 5 books were related to this literature review and just10 papers and 2 books among them were about changes in knee muscles.

  

Conclusion: The results of this survey indicated that patients with genu varum and genu valgum deformities have architectural and functional alteration in their knee muscles. According to the results most of these studies have noticed the basic changes in quadriceps muscle function and architecture. It is necessary to study more about the function of other knee muscles.

  

Key words: Genu varum, Genu valgum, Bow leg, Knock knee, Knee muscles.

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Background and Aim: Muscle fascicle length and pennation angle can be non-invasively studied by applying methods like ultrasonography. The aim of this study was to introduce fascicle length and fascicle angle for the estimation of the strength of skeletal muscle by using ultrasonography.

  

Materials and Methods: The data of this study have been driven from pubmed and authoritative references available on the internet and in libraries. In all fifteen full text articles and 30 abstracts have been collected and reviewed. Keywords such as: muscle, fascicle, pennation angle, force and ultrasonography were searched to fulfill the purpose of this study.

  

Results : Detailed information about the angles of pennation and fascicles length are important to predict muscle force. It has been suggested that changes in muscle pennation angles are positively correlated to the length of fascicle in a muscle contraction. While muscle thickness may in some case be remained constant in this relation.

  

Conclusion: Real-time ultrasonography is a noninvasive procedure to monitor the architecture of the living muscle at rest and during static and dynamic sets. It is a valuable measurement tool to estimate muscle force by measuring the muscle architecture parameters such as angle of pennation and fascicle length.

 

Keywords : Muscle, Fascicle, Pennation angle, Force, Ultrasonography

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Background and Aim : The aim of this study was to determine the effects of fatigue due to plyometric training on vertical jump ability and activity pattern of rectus femoris of dominant leg of high jump of active girls .

 

Materials and Methods : Seventeen females , mean age (21.5 ± 0.76 years ) were randomly assigned to two experimental (n = 10 ) and control ( n = 7) groups. Experimental group performed plyometric training and control group had no activity. Before and after training , vertical jump test using Ergo jump and electrical activity of rectus femoris muscle of dominant leg using electromyography were tested . The results of vertical jump test showed a decrease in performance (p: 0.04, F: 4.5) and fatigue process was confirmed . The raw EMG signal based on deep jump phases was divided in three phases and only 2 phases of the first were analyzed . In every phase, the maximum activity , amplitude and total time were obtained .respectively. M ultivariate analysis of variance (2×2) was used to compare of post-test of two groups.

 

Results : After one session training , rectus femoris maximum activity of the experimental group showed a significant decrease in pre-activation phase of motor program .

 

Conclusion : This study showed that neural fatigue due to plyometric training can occur in motor program (especially in pre-activation phase of motor program ).

  

Keywords : Deep jump, Plyometric training, Vertical jump, Electromyography, Rectus femoris muscle.

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Background and Aim : Hemiplegic shoulder pain is a common problem that its prevalence varies from 48% to 84%. This disorder limits the patient’s ability to achieve the optimal function. The objective of study was to assess the relationship between hemiplegic shoulder pain with neuromusculoskeletal disorders in post stroke hemiparesis

  

Materials and Methods: This study was an observational-analytic that fullfilled on fifty patients with acute stroke. The post stroke period was 28 days. The following items were evaluated:shoulder subluxation with X-ray, shoulder spasticity with Modified Modified Ashworth Scale (MMAS), soft tissue injury with orthopaedic tests and RSD with clinical features.

 

Results: Hemiplegic shoulder pain was present in 28 patients(56%). Seventeen patients (85%) showed shoulder subluxation, 18 patients (72%) had supraspinatus tendonitis ,13 patients (65%) had biceps tendinits, 4 patients (14/2%) had ACJ involvement, 3 patients (10/7%) had elbow flexor spasticity, 2 patients (7/1%) had shoulder adductor spasticity ,2 patients (7/1%)had shoulder internal rotators spsticity , 4 (14/2%) patients had RSD.

  

Conclusion: Results from this study show that one factor does not play role in causing hemiplegic shoulder pain and this disorder is multifactorial. Prevention of shoulder pain and performing appropriate physiotherapy can play a role in improving stroke patients’ function.

 

Keywords: Stroke, Shoulder pain, Sublxation, Muscle tone, Shoulder –Hand syndrone

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Background and Aim: Despite the widespread use of whole body vibration (WBV),especiallyin recent years, its neurophysiological mechanism is still unclear and the results about the facilitatory or inhibitory effects of WBV widely vary in different studies. The aim of this study was to compare between immediate (one session) and short term (12 sessions) effects of WBV on the spinal motor neurons excitability in healthy young men.

  

Materials and Methods: Ten voluntary non-athlete healthy young-men (mean age:26.1±2.23) were participated in this study.In the sham sessions subjects stood on the turned off vibration plate while were maintaining the semi-squat position and then after 2 weeks wash-out, vibration training sessions were done on the same position with frequency of 30 HZ and peak to peak amplitude of 3 mm training sessions (sham & vibration) consisted of 12 sessions (3 sessions per week) and 4 set in each of them, weekly one set added to the training protocol. H reflex recruitment curve of soleus muscle was recorded before and after first and also 12th sessions in both sham and vibration training protocol. Ascending slope of recruitment curve, threshold and peak amplitudes and related intensities, amplitude of Mh and Hmax/Mmax ratio were determined.

  

Results: Immediate effects of vibration training 12th session caused a significant decrease of threshold amplitude and an increase of peak intensity (p=0.05 and p=0.05 respectively). Short term WBV training significantly decreased the threshold intensity of soleus recruitment curve (p=0.01).

  

Conclusion: The results suggest the inhibitory effect of acute WBV training on the spinal motor neurons excitability. It seems that short term WBV training may be effective to facilitate the motor neurons excitability or increase the muscle spindle sensitivity.

  

Key Words: Whole body vibration, H reflex recruitment curve, Soleus muscle, Short term training

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Background and Aim: Low back pain (LBP) is the most common and expensive musculoskeletal problem in industrialized societies. One in ten people suffers from LBP once in his life. It is self-limited up to 90%, but it is common to repeat. By the way, sacroiliac joint (SIJ) is the origin of low back and pelvic pain in many cases and one of the most important elements in normal musculoskeletal function during gait cycle. Muscles are important to stabilize this joint plus to bones and ligaments. Some of the muscles (Gluteus Maximus, Biceps Femoris, Multi Fidus, Erector Spinae) contributing in gait cycle are important to transfer load through SIJ. The aim of this present study is to compare muscle activity timing during initial and mid stance phase of gait cycle.

  

Methods and Materials: Sixteen low back pain cases and fifteen healthy subjects participated in this study. A footswitch is placed beneath foot at the suffered side in LBP cases and dominant foot in control group. Two markers were on the 5^th metatarsal bone and lateral maleolus. Electrodes are placed on selected muscles according to SENIAM. Digital camera and EMG Datalink were turned on simultaneously and subject started to walk with his own favorite speed in a specific direction and path. Onset and time to peak of selected muscles were recorded during gait by Datalink and processed by its software.

  

Results: Low back pain cases showed delayed muscle onset, although it was not significant (P=0.4). Time to peak of all selected muscles in loading response event in LBP group was longer and significant (P=0.01). There was also significant difference in time to peak of all selected muscles during mid-stance event (P= 0.005) except biceps femoris muscle.

  

Conclusion: Delayed onset and longer time to peak during initial and mid stance phase of gait can be interpreted as a compensatory strategy to control trunk movements effectively, provide sufficient stability and transfer load to lumbar area efficiently.

  

Key words: Muscle activity, Low back pain, Gait, Trunk muscles, Lower Limb Muscles

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Background and Aim: Regarding to high prevalence of low back pain (LBP) in athletes and its effect on their athletic function, an accurate evaluation before planning the rehabilitation program seems necessary in athletes with LBP. It should be considered that human movements are like as a kinetic chain. It means that any problems in every parts of this chain can cause dysfunction in the other parts of the chain. Not taking attention to the relationships between different parts of this chain may result in suboptimal rehabilitation. Therefore, focusing treatment on the entire parts of the kinetic chain besides the injured part, may prevent recurrenceof the dysfunction. Since in the kinetic chain hip muscles act as a link between lower extremities and trunk, the purpose of the present study was to evaluate and compare muscles strength of hip joint in female athletes with and without non-specific chronic LBP.

  

Materials and Methods: Fifteen healthy female athletes and 15 female athletes with non-specific chronic LBP participated in this study. Their age was between 18-30 years. Hip extension, abduction and external rotation strength in all participants were measured. A hand-held dynamometer (HHD) was used to measure muscle strength. Since fixing HHD by examiner’s hand is fraught with error, it is fixed by a stable frame.

  

Results: The maximum strength value of hip extension and abduction in female athletes with LBP were significantly lower than these measures in healthy group (P < 0.05). No significant differences were seen in the maximum value of hip external rotation strength between two groups (P > 0.05).

  

Conclusion: The results of the present study show that hip extension and abduction strength in female athletes with LBP were lower than these measures in healthy group. Therefore, hip strength measurements besides the examination of the spinal column seem to be necessary in evaluation and rehabilitation of the patients with LBP.

  

Key Words: Non-Specific Chronic Low Back Pain, Hip Muscles Strength, Athlete

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Background and Aim: According to the further tendency of osteoporotic people to use the hip strategy to maintain stability, in present study, the relationship between hip, ankle and back extensor muscles strength and functional balance in healthy and osteoporotic postmenopausal women were evaluated.

  

Materials and Methods: Forty-five volunteer postmenopausal women were divided into two normal and osteoporosis groups according to their bone mineral density. Maximal isometric strength of hip, ankle, and back extensor muscles were assessed by a hand-held digital dynamometer. Functional balance was assessed by Near Tandem Stand (NTS), Star excursion (SE) and Figure of 8 walking (F8W) tests.

  

Results: In osteoporosis group, all muscle groups were significantly weaker than the normal group (P<0.05), and the time of F8W test was significantly more than normal group (P=0.031). Also, in osteoporosis group, hip adductors and extensors showed a significant correlation with three functional balance tests (P<0.05).

  

Conclusion: Regarding to decrease of muscle strength in osteoporotic women and its relationship to declining of functional balance in ADL, strengthening of hip and ankle muscle groups should be considered in their rehabilitation programs.

 

Keywords: Muscle strength, Functional balance, Postmenopausal women, Osteoporosis.