Inclusion Criteria:  Patients:  Male and female patients with chronic whiplash associated disorder that meet the Quebec Task Force Classification of whiplash grade II Within approximately four weeks of their whiplash injury Age 18-60 Participants capable of giving informed consent  Healthy Volunteers:  Free of neck or upper limb pain No history of a whiplash injury or of neck or arm pain lasting >3 months or any recent cervical or upper limb trauma requiring medical treatment. Age 18-60 Participants capable of giving informed consent  Exclusion Criteria:  Patients:  Diagnosis of whiplash grade I (neck complaints without physical signs), III (obvious neurological signs) or IV (fracture or dislocation) Experienced concussion or loss of consciousness as a result of the accident Previous history of whiplash  Previous history of neck pain or headaches that required treatment  All participants (patients and healthy volunteers):  Unsuitability to undergo MRI (assessed with the MRI screening questionnaire) Pregnant History of inflammatory disease (e.g. autoimmune diseases, rheumatoid arthritis), neuropathy, diabetes, cancer or non-medically controlled hypertension Current ongoing steroid treatment Participants with an inadequate understanding of English will also be excluded