title: Altered ventral neck muscle deformation for individuals with whiplash associated disorder compared to healthy controls - a case-control ultrasound study.
abstract: Previous studies have shown altered neck muscle function in individuals with chronic whiplash associated disorder (WAD). However, we lack real-time investigations with non-invasive methods that can distinguish between the different ventral neck muscle layers. This study investigated deformations and deformation rates in the sternocleidomastoid (SCM), longus capitis (Lcap), and longus colli (Lco) muscles with real-time ultrasonography. Twenty-six individuals with WAD were compared with 26 controls, matched for age and sex. Ultrasound imaging of the SCM, Lcap, and Lco were recorded during 10 repetitive arm elevations. The first and tenth arm elevations were post-process analyzed with speckle tracking. There were few significant differences in the deformations or deformation rates in the SCM, Lcap, and Lco between the WAD and control group. In controls, deformations and deformation rates showed linear positive relationships between SCM/Lcap, SCM/Lco, and Lcap/Lco which increased from the first arm elevation (R(2) = 0.14-0.70); to the tenth arm elevation (R(2) = 0.51-0.71). The WAD group showed similar or weaker linear relationship (R(2) < 0.19) during the tenth compared to the first (R(2) < 0.44) arm elevation except for deformations in Lcap/Lco (R(2) = 0.13-0.57). This result indicated that deformations and deformation rates in one muscle were correlated by similar deformations and deformation rates in other neck muscles in the control group, but this interplay between muscles was not found in the WAD group.
authors.affiliation: Centre for Clinical Research Sörmland, Uppsala University, Eskilstuna, Sweden; Department of Medical and Health Sciences, Division of Physiotherapy, Faculty of Health Sciences, Linköping University, Linköping, Sweden. Electronic address: gunnel.peterson@liu.se.
authors.forename: Gunnel
authors.initials: G
authors.lastname: Peterson
authors.affiliation: Department of Neurobiology, Care Sciences and Society, Division of Physiotherapy, Karolinska Institutet, Sweden; Department of Physical Therapy, Karolinska University Hospital, Sweden.
authors.forename: Åsa
authors.initials: Å
authors.lastname: Dedering
authors.affiliation: Department of Medical and Health Sciences, Division of Physiotherapy, Faculty of Health Sciences, Linköping University, Linköping, Sweden.
authors.forename: Erika
authors.initials: E
authors.lastname: Andersson
authors.affiliation: Department of Chemistry, Computational Life Science Cluster, Umeå University, Sweden.
authors.forename: David
authors.initials: D
authors.lastname: Nilsson
authors.affiliation: Department of Chemistry, Computational Life Science Cluster, Umeå University, Sweden.
authors.forename: Johan
authors.initials: J
authors.lastname: Trygg
authors.affiliation: Department of Chemistry, Computational Life Science Cluster, Umeå University, Sweden.
authors.forename: Michael
authors.initials: M
authors.lastname: Peolsson
authors.affiliation: Centre for Clinical Research Sörmland, Uppsala University, Eskilstuna, Sweden; Uppsala University, Public Health & Caring Sciences, Family Medicine & Preventive Medicine Section, Uppsala, Sweden.
authors.forename: Thorne
authors.initials: T
authors.lastname: Wallman
authors.affiliation: Department of Medical and Health Sciences, Division of Physiotherapy, Faculty of Health Sciences, Linköping University, Linköping, Sweden.
authors.forename: Anneli
authors.initials: A
authors.lastname: Peolsson
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D015601:Injury Severity Score; D008297:Male; D008875:Middle Aged; D018763:Muscle Fatigue; D009334:Neck Muscles / Q000503:physiopathology*; D010147:Pain Measurement; D012016:Reference Values; D018608:Ultrasonography, Doppler / Q000379:methods; D014911:Whiplash Injuries / Q000000981:diagnostic imaging* / Q000503:physiopathology*
keywords: Neck muscles; Ultrasonography; Whiplash injury