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Background and aim: Since 1998, the effect of traction on the H- reflex has been investigated by Hiraoka and the other researchers. Some of them have been done on lower extremity and the other on the upper extremity. The effect of traction was assessed by H reflex amplitude. Different results have been achieved. The new method which has been used since 2000, the effect of cervical traction on the H reflex was carried out by measuring H reflex slope .In this experiment the effect of manual cervical traction has been studied on the H slope of the upper extremity. Now we have sought to extend this work by examining the effects of cervical traction with 3 kg force on the H slope of the lower extremity 

Materials and Methods: This study was administered to sixteen healthy men with a mean age 23.12 of years and SD=2.55. The parameters of H reflex were recorded before and after of cervical traction .All data were analyzed with SPSS (V: 11.5).    

Results: The results showed that, there were no significant differences between before and after the application of cervical traction in H reflex parameters, ratio of H max/M max amplitude and M slope. But H slope and ratio of H slope /M slope were increased significantly after the application of traction (P<0.001).

Conclusion: The present study showed that traction with 3 Kg force can increase motor neuron excitability of soleus muscle and this result is against the previous study. This could be due to the application of the new method (H slope), which is more precise.

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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: 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: Proprioception is one of the most precise and delicate senses of the human body. It plays an important role in coordination and postural control by protecting the body against trauma and accidents. Although many studies have assessed the effect of fatigue on proprioception in the limbs and the low back region, but a few studies have investigated its possible effect on the cervical region.

  

Material and Methods: Seventeen (8 women, 9 men) young and healthy volunteers were asked to perform the Cervicocephalic Relocation Test (CRT) to the neutral head position by relocating the head on trunk after actively rotating the head to right and left sides, in two conditions before and after muscular fatigue. Absolute, constant and variable errors were used to evaluate cervical joint repositioning accuracy.

  

Results: Fatigue had no effect on cervical joint position sense, Furthermore no considerable difference was seen between male and female subjects (p>0.05).

  

Conclusion: The results suggest that following isometric fatigue of upper trapezuis muscles, no change is produced in the repositioning accuracy of both sexes. Furthermore, sex had no effect on cervical joint proprioception.

  

Key Words: Cervical joint position sense, Fatigue, Proprioception, Cervicocephalic Relocation Test (CRT).

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Background and Aim: Proprioception is a type of feedback from limbs to CNS which defines a sensory tools to contribute position sense and movement sense.

Precise and controlled movements are important sections of sports and activity daily living which needs to accurate information of proprioception.

High concentration of proprioceptors are reported in cervical spine, sacroiliac and ankle joint. The purpose of this study was to compare repositioning error of cervical spine on high level badminton and basketball players and healthy subjects.

  

Materials and Methods: Twenty female basketball players (23.40 years old), 20 female badminton players (24.81years old) and 20 healthy female (24,95years old) subjects were recruited to participate in this study. Cervical total range of motion (ROM) and repositioning error in target angle (30% of full ROM in each movement) of flexion, extension, right and left lateral flexion and rotation were measured by CROM apparatus.

Results : Our results indicate that two groups of athletes has significant differences with non-athletic subjects in flexion, extension, left lateral flexion and ro tation and there were significant differences in right lateral flexion and right rotation between badminton players and non-athletic subjects (P<0.005).

  

Conclusion : Cervical proprioception may improve with specific sport movements. Basketball and badminton are non-contact sports that needs to eye and hand coordination, as our results showed that the cervical repositioning error was decreased in athletics related to non-athletic subjects, the mentioned sports may improve proprioception.

 

Key Words: Proprioception, Cervical, Repositioning error, Basketball, Badminton

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Background and Aim: Proprioception is a component of somatosensory system. One of the most important somatosensory receptors is muscle spindles. Neck area with high density of muscle spindle, plays a significant role in providing this sense. With repeated contact sports, with high trauma on head and neck region, it is likely that proprioception will be impaired. The present study was conducted to compare proprioception between wrestlers, taekwondo players and non-athlete subjects to determine the effect of trauma on proprioception of craniocervical region.

 

Material and Methods: This study was a case-control study of 75 male with the age range of 18-30 years (Including: 25 professional wrestlers, 25 professional taekwondo players and 25 non-athlete subjects). Participants were selected through simple non-probability sampling. To assess proprioception of craniocervical region, angular repositioning of two positions (neutral and 50% of range of motion) was evaluated by using the cervical range of motion device (CROM device). The statistical method which used in this study was one way ANOVA.

 

Results: Accuracy of target repositioning (50% of range of motion) of extension, right and left rotation were significantly different between three groups (p<0.05). Returning to neutral position from mentioned movement was associated with a significant error (p<0.05).

 

Conclusion: It is assumed that proprioception of craniocervical region has been affected by trauma in wrestlers and taekwondo players, so that the accuracy of head repositioning for both neutral and target positions were reduced in wrestlers. However, taekwondo players had more errors in repositioning of target angle.

 

Keywords: Proprioception, Repositioning error, Craniocervical, Wrestlers, Taekwondo players