The mean passive cervical rotational range of motion measured at three months posttreatment was significantly greater in Group 2 ( 101.1 ) than that in Group 1 ( 86.4 ) , and the thickness , cross-sectional area , and red pixel intensity of the affected sternocleidomastoid muscle were all less in Group 2 ( 7.8 mm , 100.3 mm ( 2 ) , and 126.1 , respectively ) than those in Group 1 ( 9.6 mm , 121.5 mm2 , and 140.5 , respectively ) .