NECK SEMISPINALIS CAPITIS MUSCLE SIZE IN SITTING AND PRONE POSITIONS MEASURED BY REAL-TIME ULTRASONOGRAPHY

Objective: To examine the reliability of measurements of semispinalis capitis muscle (SECM) cross-sectional area (CSA) in prone and sitting positions, and to compare the muscle size in these two positions. Desi gn: Semispinalis capitis CSA was measured twice a day on two successiv e days with a real-lime ultrasound apparatus. Subjects: Eighteen males (aged 19-34 years) and 28 females (aged 19-34 years) were studied for the reliability test. Seven males and 12 females were randomly select ed to compare SECM size in sitting and prone positions. Results: The i ntraclass correlation coefficient (ICC) for repeatability measurements was r = 0.98 for the two positions. The correlation of the CSA in sit ting and in prone positions was r = 0.93 (p<0.01). There were no signi ficant differences between CSA, linear dimensions and shape ratio of S ECM in the two positions. Conclusions: In this study SECM ultrasonogra phy appeared to be an accurate method in both positions, and position as such had no significant effects on the SECM cross-sectional size. S uch accuracy allows neck muscle evaluation in clinical diagnosis and i n follow-up studies during neck rehabilitation programmes.