New research could bring hope for whiplash sufferers

Published earlier this year, Professor Annina Schmid and her team's recent papers in journals Brain and Pain show that people with whiplash-associated disorders (WAD) are often dealing with nerve injury that may contribute to their chronic pain symptoms. This challenges the prevailing theory that WAD is strictly a musculoskeletal problem, associated with a person’s joints, bones and muscles.

Whiplash-associated disorders, following road traffic accidents, affect millions of people globally each year. These injuries are also associated with significant social and economic costs, with up to half of all those affected living with pain and disability for several years following whiplash.

Unfortunately, it remains unclear why so many people are unable to recover after whiplash. This can leave WAD patients facing stigma and a lack of understanding around their pain symptoms.

Along with her Nuffield Department of Clinical Neurosciences, Oxford University team, and Professor Andrew Dilley's group at Sussex University, Professor Schmid has investigated whether damage to peripheral nerves (the part of the nervous system outside the brain and spinal cord) may contribute to pain symptoms in people with WAD.

She explains, “We followed a group of 129 people who had recently sustained a whiplash injury, comparing them to healthy individuals. We used a combination of neurological tests, sensory testing, neuroimaging (MRI), and blood and skin markers of nerve damage to assess whether nerve injury or neuroinflammation was present.”

The team found that two-thirds of the study participants showed signs of nerve pain and dysfunction shortly after whiplash injury. At six months after injury, nerve pain persisted in one-third of patients.

As well as this, many participants were less able to sense temperature, vibration and light touch, with these deficits in warm and mechanical sensations persisting even after six months.

At a biological level, the team observed that levels of a specific protein, linked to nerve damage, were elevated in people shortly after whiplash injury – as compared to a healthy control group. MRI scans additionally showed evidence of inflammation in small nerves around the neck, and blood tests indicated increased levels of inflammatory molecules in patients after whiplash injury.

Together, these findings demonstrate that, for many people with WAD, mild nerve injury and neuroinflammation may contribute to pain symptoms. There is a need for clinicians to be mindful of this when assessing patients with WAD symptoms.

Professor Schmid adds, “Often, we can’t find evidence of injury after whiplash. This can make patients feel invalidated or question their pain. Now that we have found evidence of nerve involvement in some patients, it may help reduce that stigma.

“Pain research is desperately needed. The Foundation’s funding has enabled us to deliver exciting and potentially ground-breaking results in the field of whiplash, taking us closer to developing targeted and effective interventions for people living with pain.”

Read the full BRAIN paper here >>

Read the full PAIN paper here >>