For some injured people, moving makes the pain better, for others, moving makes the pain worse. Why?
Activity is considered to be an important part of the treatment of whiplash injury. Following a whiplash injury, medical professionals typically recommend active treatment. Physiotherapy is the most frequently prescribed active treatment for whiplash injury. Inactivity can lead to a number of problems such as deconditioning, distress and disability. On the other hand, activity can speed up recovery, and activity has also been shown to reduce the severity of pain.
Recent research led by Professor Michael Sullivan and his team shows that activity involvement does not lead to pain relief in everyone. For some injured individuals, activity involvement might actually contribute to a worsening of pain symptoms.
In a series of studies, participants with whiplash injuries were asked to rate their pain as they lifted a series of 18 weights. For most participants, pain levels either stayed the same or decreased as they performed the lifting task. However, for approximately 30% of injured participants, pain levels increased. Professor Sullivan used the term ‘sensitivity to movement evoked pain’ to describe the tendency for pain to increase following repeated activity.
According to Professor Sullivan, it is not yet known why activity should lead to pain relief in some people while leading to increasing pain in others. It is clear however that for those who experience increasing pain in response to repeated activity, the rehabilitation period will be more challenging. Individuals who experience increasing pain might feel that physical therapy is making them worse, or they might think it best to avoid activity altogether.
According to Professor Sullivan, activity interventions are still important even for individuals whose pain seems to increase following repeated activity. Professor Sullivan emphasised that just because the pain feels more intense, it does not mean that the condition is getting worse.
Professor Sullivan and his team are currently conducting research trying to find ways of treating ‘sensitivity to movement-evoked pain’. Such treatments could make it easier for injured individuals to participate in the level of activity necessary to ensure recovery following whiplash injury.
Mankovsky-Arnold, T., Wideman, T.H., Larivière, C., Sullivan, M.J.L. (2014). Measures of spontaneous and movement-evoked pain are associated with disability in patients with whiplash injuries. Journal of Pain, 15, 967 – 975.
Sullivan, M.J.L., Lariviere, C., Simmonds, M. (2010). Activity-related summation of pain and functional disability in patients with whiplash injuries. Pain, 151: 440 – 446.