title: Correlation between deep cervical flexor muscle thickness at rest and sternocleidomastoid activity during the craniocervical flexion test.
abstract: The purpose of this study was to clarify the relationship between the thickness of the deep cervical flexor muscles (longus capitis and longus colli) at rest and sternocleidomastoid activity during the craniocervical flexion test (CCFT). Thirteen healthy males participated in this study. The thickness of the deep cervical flexor muscles was measured by ultrasound imaging in a relaxed supine position. Activity of the sternocleidomastoid was measured by electromyography during the CCFT at five incremental levels (22, 24, 26, 28, and 30 mm Hg). Correlations between normalized muscle thickness relative to body mass index and sternocleidomastoid activity were determined. Significant negative correlations were observed between normalized muscle thickness and activity of the sternocleidomastoid at 26 (r = -0.622, P = 0.023) and 28 mmHg (r = -0.653, P = 0.015). Individuals with smaller deep cervical flexor muscles exhibited increased activity in the sternocleidomastoid during the CCFT.
authors.affiliation: Department of Rehabilitation, Faculty of Health Science and Technology, Kawasaki University of Medical Welfare, 288, Matsushima, Kurashiki City, 701-0193, Japan. Electronic address: ishida@mw.kawasaki-m.ac.jp.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ishida
authors.affiliation: Department of Rehabilitation, Faculty of Health Science and Technology, Kawasaki University of Medical Welfare, 288, Matsushima, Kurashiki City, 701-0193, Japan.
authors.forename: Tadanobu
authors.initials: T
authors.lastname: Suehiro
authors.affiliation: Master's Program in Rehabilitation, Kawasaki University of Medical Welfare, 288, Matsushima, Kurashiki City, 701-0193, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Ono
authors.affiliation: Department of Rehabilitation, Faculty of Health Science and Technology, Kawasaki University of Medical Welfare, 288, Matsushima, Kurashiki City, 701-0193, Japan.
authors.forename: Chiharu
authors.initials: C
authors.lastname: Kurozumi
authors.affiliation: Department of Rehabilitation, Faculty of Health Science and Technology, Kawasaki University of Medical Welfare, 288, Matsushima, Kurashiki City, 701-0193, Japan.
authors.forename: Susumu
authors.initials: S
authors.lastname: Watanabe
mesh_terms: D000293:Adolescent; D002574:Cervical Vertebrae; D004576:Electromyography; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D009334:Neck Muscles / Q000000981:diagnostic imaging / Q000502:physiology*; D012146:Rest; D055815:Young Adult
keywords: Deep cervical flexor muscles; Electromyography; Muscle size; Ultrasound imaging