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Background and Aim: Hamstring muscles are biarticular muscles, which conducted to pelvic and knee. Shortness of hamstring muscles can influence on the upper and lower joints of its attachment .With respect of the high prevalence of shortness of  these muscles, accurate assessment of these muscles is important. There are many tests for assessment of hamstring muscles length During using the straight leg raise (SLR) test, pelvic rotation can contribute to the angle of SLR, while pelvic movement in passive knee extension (PKE) is limited. This study was designed to measure the relationship between two alternative tests in order to use of simple and accurate PKE test for measuring of hamstring length.

Material & Method: 3308 healthy girls (3-17 years) were tested, and hamstring length were determined with using of two tests (SLR and PKE) for both side of lower limbs and measured of active SLR and popliteal angle (PA) with goniometer.

Results: Pearson che-squre analysis showed significant relationship(r = 0.529(R), r = -0.435(L), p< 0/05) between PKE and SLR .

Conclusion: Results demonstrated relationship between two tests, in all of ages and both side. SLR and PKE tests can use for assessing of hamstring muscles shortness, but PKE test may be a useful alternative in comparison with activeSLR for providing an indication of hamstring muscle length.

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Background and aim: With respect to attachment and mechanical relationship of hamstring and calf muscles, interaction between their function is unavoidable. Inspite of prevalence of hamstring and calf muscles shortness, there is not any statistical data about the relationship of shortness of above-mentioned muscles in Iran. The aim of this study was to verify of this prevalence.

Materials and methods: In this study 3308 healthy girls with age 3-17 years old participated. Length of calf muscles with dorsi flexion angle and hamstring with hip flexion angle (SLR) in both side were measured.

Results: The prevalence of hamstring and calf muscles shortness with together was20% in right and 25% in left side .The Prevalence of hamstring and calf muscles shortness with together in 20 district was greater than 3.The greatest amount was seen in secondary school(31.6%).               

Conclusion:The results indicated that most of subjects who had hamstring shortness, they had also calf muscles shortness, so if there is any shortness in one of them, we shouhd pay attention to shortness of the another.

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Background and aim: The aim of this study was to verify the relationship between pelvic tilt and lumbar lordosis with muscle tightness, muscle strength, BMI, and age in standing position.

Material and methods: In this study, 75 healthy female subjects participated with age range 20-70 years, mean (SD) = 40.66 (13.69). Pelvic tilt and lumbar lordosis were measured in standing position with pelvic inclinometer and flexible ruler respectively. The length of muscles, including: erector spinae, iliopsoas, rectus femoris, hamstrings, tensor fascia lata & ilio tibial band, and gastrocnemius were assessed by Schober, Thomas, Ely, 90/90 SLR, Ober tests and passive dorsiflexion of foot, respectively. The strength of muscles, including: rectus abdominis, transversus abdominis, left & right obliqus, Gluteus maximums & medius, and quadriceps were evaluated by manual muscle tests.

 Results: The relationship between pelvic tilt and lumbar lordosis with muscle strength, BMI, and age was poor. Muscle tightness and muscle strength had no significant effect on pelvic tilt and lumbar lordosis.

Conclusion: The results of this study indicated that the evaluated variables including: pelvic tilt and lumbar lordosis, have poor correlation with muscle tightness, muscle strength, BMI, and age. 

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Background and Aim: Core stability is the ability of the lumbopelvic- hip complex to prevent buckling of the vertebral column and return it to equilibrium following perturbation. It has been demonstrated that trunk muscle activity occurs before the activity of the prime mover of the limb. Core stability is seen as being pivotal for efficient biomechanical function to maximize force generation and minimize joint loads in all types of activities ranging from running to throwing. The aim of this study was to examine the correlation between core stability and lower extremity function in female athletes.

 Materials and Methods: Thirty volunteer female athletes with mean age (SD)=23(3.8) years old, participated in this study. They performed two series of tests: core stability tests (hip isometric abduction and lateral rotation, double leg lowering, trunk extension – flexion and left and right lateral flexion endurance, and double leg lowering), and lower extremity function tests (star excursion balance tests in three directions, vertical jump, single and triple hopping, stairs sprinting, 6 m hopping, and shuttle run).

Results: The results of this study showed that the strength of hip isometric abduction with stairs sprinting, 6 m hopping , and with star excursion balance test in three directions had r=-0.430, r=-0.367and r=0.515 respectively and all significant. Also , right lateral flexion endurance with shuttle run (r=0.367) , double leg lowering with vertical jump (r=0.42), trunk extension endurance with vertical jump (r=-0.404) ,were significantly correlated. In the other items there were no relationship between core stability and lower extremity function (p>0.05).

Conclusion: There is a relationship between core stability and lower extremity function but studies have not supported them. However, the data showed that core stability is moderately too weak related to lower extremity function, core stability could not be measured with these tests and they are not good indicators for lower extremity function. Evaluation of the core should be dynamic, and compromise assessment of the specific functions which specialize for athletic groups.

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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: According to the attachments lumbar spine and pelvic muscles, it seems that pelvic tilt and lumbar lordosis have previous studies about this relationship have shown different results and these conflicting results can hamper therapist to set a correct therapeutic plan. The aim of this study was to examine this relationship in a large sample and with more accurate instruments. Materials and Methods: One hundred and eighty healthy women (20-65 year-old) with a mean age of 41.45 12.27 participated in this study. Pelvic tilt was measured by inclinometer and lumbar lordosis by flexible ruler. Statistical tests have been performed by SPSS (version 11.5) computer software. Results: The results of this study showed a weak correlation between pelvic tilt and lumbar lordosis (r =0.16, p<0.05). This association was little affected by age. Conclusion: This study has examined the relationship between pelvic tilt and lumbar lordosis of healthy women in static position. The present study showed a weak correlation between pelvic tilt and lumbar lordosis in healthy women.