The Brain in Pain
Cortical contributions to Complex Regional Pain
Syndrome
Dr Janet Bultitude
Overview
1. Cognitive and cortical changes in CRPS
2. Possible role in clinical symptoms
3. Implications for treatment
4. Proposed mechanisms
Complex Regional Pain Syndrome
Complex Regional Pain Syndrome
“As the pain increases, the general sympathy
becomes more marked. The temper changes
and grows irritable, the face becomes anxious,
and has a look of weariness and suffering. The
sleep is restless, and the constitutional
condition, reacting on the wounded limb,
exasperates the hyperaesthetic state, so that
the rattling of a newspaper, a breath of air…the
vibrations caused by a military band, or the
shock of the feet in walking, gives rise to
increase of pain.”
Silas Weir Mitchel, 1864
Distorted body representation
Lewis et al., 2010, Pain
Distorted body representation
• “I feel disgust, I know it sounds a very
strong word to use but I’m disgusted that
my arm is this way.”
• “It was just like this foreign body you were
carrying around with you cause it didn’t
feel like it was part of you.”
Lewis et al., 2007, Pain
Distorted body representation
• Difficulty locating / moving the limb unless
directly looking at it
• Difficulty identifying fingers from touch
• Referred pain, or pain when viewing an
object approaching the limb
• Movement-induced pain greater when
viewing hand through magnifying lens, less
when viewing hand through minimising
lens.
Cortical reorganisation
Maihöfner et al., 2004, Neurology
Cortical reorganisation
Gieteling et al., 2008, Pain
Mechanisms of CRPS
“When our senses present us with discordant information,
such as when our eyes give our brain information that does not
agree with our senses of body position, balance, and
equilibrium, we feel nausea. Less familiar is the notion that
discordance between awareness of motor intention, muscle
and joint proprioception, and vision may result in our feeling
pain.”
1999, The Lancet
Poke your eye
Predictive signal
True sensory outcome
???
Predictive signal
True sensory outcome
Implications for treatment
???
Predictive signal
True sensory outcome
Healthy hand
representation
Healthy hand
representation
Predictive signal
True sensory outcome
???
Predictive signal
True sensory outcome
Prism adaptation
Prism adaptation
Sumitani et al., 2007, Neurology
Prism adaptation
Transcranial Direct Current
Stimulation
Transcranial Direct Current
Stimulation
Antal et al., 2010; The Clinical Journal of Pain
Proposed mechanisms
Immobilization-driven reorganisation?
Immobilized IF
Healthy IF
Lissek et al., 2004, Current Biology
Direct immune mechanisms?
Overview
1. Cognitive and cortical changes in CRPS
2. Possible role in clinical symptoms
3. Implications for treatment
4. Proposed mechanisms
Take-home messages
Cortical origins to pain
≠
It’s all just in your head
Take-home messages
• Importance of:
– Early recognition
– Aggressive intervention
– Multiple simultaneous approaches
– Cognitively- and cortically-targeted treatments
Now recruiting
We are looking for volunteers with CRPS for
a study investigating two potential
treatments that target cognitive and cortical
changes.
Interested patients can contact me at
crps@fmrib.ox.ac.uk
or
jbultitude@fmrib.ox.ac.uk