TY - JOUR T1 - Assessing the Dimensions of Semi-Spinalis Capitis Muscle and Isometric Strength of Cervical Extensor Muscles in Different Neck Positions in Healthy Female Individuals TT - بررسی ابعاد عضله سمی اسپاینالیس کپیتیس و قدرت ایزومتریک عضلات اکستانسور گردن در وضعیت های مختلف در زنان سالم JF - J-Mazand-Univ-Med-Sci JO - J-Mazand-Univ-Med-Sci VL - 22 IS - 88 UR - http://jmums.mazums.ac.ir/article-1-990-en.html Y1 - 2012 SP - 71 EP - 79 KW - Ultrasonography KW - semi-spinalis capitis KW - strength KW - muscle size N2 - Background and purpose: Ultrasonography is a reliable and valid method to assess the strength of neck extensors and measuring the neck muscles dimensions. Cervical muscles strength and dimensions may change in different positions. The aim of this study was to compare the strength of cervical extensor muscles and dimensions of semi-spinalis capitis muscle (SECM) in three different neck positions in healthy female individuals. Materials and methods: The research population included 30 female students, 18-24 years of age. Right SECM at the level of third cervical vertebrae was measured by ultrasonography in order to assess the isometric strength of neck extensor muscles in neutral, flexion and extension positions. The size of muscle was calculated by multiplying the anterior-posterior and lateral dimension of the muscle. Afterwards, the muscle strength was measured by a measuring device. One way-ANOVA was used to analyze the data. Results: The SECM size was significantly bigger in extension than that of the neutral and flexion positions (P M3 ER -