Neuroinflammation as a Predictor of Chronicity in Whiplash

Whiplash describes an injury to the neck caused by a rapid movement of the head. It often occurs during a motor vehicle collision, causing considerable pain and distress. Most patients are diagnosed with whiplash associated disorder grade-2 (WAD2). Half of these patients develop chronic pain. Current treatments for patients are ineffective. It is difficult to predict which patients will develop chronic pain, and therefore how to manage these patients. The characteristics of pain felt by many patients with WAD2 suggests that symptoms are caused by an injury to the nerves in the neck and arm. However, on clinical examination there is no indication that these nerves are significantly injured.

Work from the investigators' laboratory suggests that nerves may be inflamed. In this study, the contribution of nerve inflammation to symptoms early following whiplash will be established. It will determine whether clinical tests are able to identify those patients with inflamed nerves. It will also determine whether the presence of nerve inflammation can be used to identify patients who develop chronic pain. The study will recruit 115 patients within one month following a whiplash injury and thirty-two healthy volunteers. Participants will undergo a clinical assessment. A blood sample will be taken to look for inflammatory proteins and magnetic resonance imaging will be used to identify nerve inflammation in the neck and wrist. Questionnaires to establish neck disability, pain quality and psychological distress will be completed. MRI findings will be compared to healthy controls. At six-months, patients will be asked to repeat the questionnaires, which will be used to identify those patients who have recovered. Twenty-five recovered and twenty-five non-recovered patients will undergo a repeat MRI and clinical assessment. Although patients on this study will not directly benefit, the findings will help with early diagnosis and could refocus treatment to reduce chronic pain.


Eligibility Criteria:
Inclusion Criteria:

Patients:

1. Male and female patients with chronic whiplash associated disorder that meet the Quebec Task Force Classification of whiplash grade II
2. Within approximately four weeks of their whiplash injury
3. Age 18-60
4. Participants capable of giving informed consent

Healthy Volunteers:

1. Free of neck or upper limb pain
2. 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.
3. Age 18-60
4. Participants capable of giving informed consent

Exclusion Criteria:

Patients:

1. Diagnosis of whiplash grade I (neck complaints without physical signs), III (obvious neurological signs) or IV (fracture or dislocation)
2. Experienced concussion or loss of consciousness as a result of the accident
3. Previous history of whiplash
4. Previous history of neck pain or headaches that required treatment

   All participants (patients and healthy volunteers):
5. Unsuitability to undergo MRI (assessed with the MRI screening questionnaire)
6. Pregnant
7. History of inflammatory disease (e.g. autoimmune diseases, rheumatoid arthritis), neuropathy, diabetes, cancer or non-medically controlled hypertension
8. Current ongoing steroid treatment
9. Participants with an inadequate understanding of English will also be excluded