Are there implications for morphological changes in neck muscles after whiplash injury?
METHODS
Literature review.


OBJECTIVE
To review the evidence related to the morphological changes (atrophy and fatty degeneration) of neck muscles in whiplash-associated disorders (WAD) and to highlight emerging evidence for the pathophysiological mechanisms behind muscle degeneration and their potential role in the transition from acute to chronic pain after whiplash injury from a motor vehicle crash (MVC).


BACKGROUND
Magnetic resonance imaging (MRI) can be regarded as the gold standard for muscle imaging. There is emerging evidence to highlight in vivo features of neck muscle degeneration in patients with chronic WAD and the temporal development of such acute changes after MVC. However, the precise underlying mechanisms for such changes and their influence on functional recovery after whiplash remain largely unknown.


METHODS
Literature review of available evidence from both the authors' previous studies and other similar bodies of work.


RESULTS
Studies have quantified degenerative changes in the neck muscles of patients with acute and chronic whiplash with structural MRI applications.


CONCLUSIONS
Current evidence from structural MRI based studies demonstrates the widespread presence of fatty infiltrates in neck muscles of patients with chronic whiplash. Such findings have not shown to feature in patients with chronic insidious onset neck pain, suggesting traumatic factors play a role in their development. Recent studies have revealed that muscle fatty infiltrates manifest soon after whiplash but only in those with higher pain and disability and symptoms of post-traumatic stress disorder. The possibility that such muscle changes are associated with a more severe injury including poor functional recovery remains the focus of current research efforts.
Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA. j-elliott@northwestern.edu
James M
JM
Elliott
D006801:Humans; D008279:Magnetic Resonance Imaging; D009133:Muscular Atrophy / Q000209:etiology / Q000503:physiopathology*; D009334:Neck Muscles / Q000473:pathology / Q000503:physiopathology*; D019547:Neck Pain / Q000209:etiology / Q000503:physiopathology*; D014911:Whiplash Injuries / Q000150:complications / Q000503:physiopathology*