title: Disturbed jaw behavior in whiplash-associated disorders during rhythmic jaw movements.
abstract: As shown previously, "functional jaw movements" are the result of coordinated activation of jaw as well as neck muscles, leading to simultaneous movements in the temporomandibular, atlanto-occipital, and cervical spine joints. In this study, the effect of neck trauma on natural jaw function was evaluated in 12 individuals suffering from whiplash-associated disorders (WAD). Spatiotemporal characteristics of mandibular and concomitant head movements were evaluated for three different modes of rhythmic jaw activities: self-paced continuous maximal jaw-opening/-closing movements, paced continuous maximal jaw-opening/-closing movements at 50 cycles/minute, and unilateral chewing. Compared with healthy subjects, the WAD group showed smaller magnitude and altered coordination pattern (a change in temporal relations) of mandibular and head movements. In conclusion, these results show that neck trauma can derange integrated jaw and neck behavior, and underline the functional coupling between the jaw and head-neck motor systems.
authors.affiliation: Department of Odontology, Clinical Oral Physiology, Umeå University, S-901 87 Umeå, Sweden.
authors.forename: B
authors.initials: B
authors.lastname: Häggman-Henrikson
authors.forename: H
authors.initials: H
authors.lastname: Zafar
authors.forename: P-O
authors.initials: PO
authors.lastname: Eriksson
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D016022:Case-Control Studies; D005157:Facial Pain / Q000209:etiology*; D005260:Female; D019416:Head Movements / Q000502:physiology; D006801:Humans; D008297:Male; D008334:Mandible / Q000503:physiopathology*; D008409:Mastication; D008875:Middle Aged; D009068:Movement; D009334:Neck Muscles / Q000503:physiopathology; D019547:Neck Pain / Q000209:etiology; D010147:Pain Measurement; D018709:Statistics, Nonparametric; D013705:Temporomandibular Joint Disorders / Q000209:etiology* / Q000503:physiopathology; D014911:Whiplash Injuries / Q000150:complications* / Q000503:physiopathology*