Basic Science and Pain Models

Professor Graven-Nielsen has worked with human pain models for 25 years, pioneering a lot of the work within musculoskeletal pain. 

What are pain models?

It's a model of mimicking the pain system. Some people work on this from a computational perspective, so they're trying to mimic a very complex process in the physiology of nerves to figure out what is happening. But we study the human pain system in healthy subjects and try to study what is actually happening when they feel a very particular type of pain. We see the pain system as the black box from outside. And we try to either induce pain or assess pain, and then see how the pain system works in that particular subject. 

If we take this from basic animal research and try to make a model of a nerve lesion, for example, we cannot do that in humans. But we can do more simple things. We can start to understand what is happening specifically with the pain system. And the reason this is so important for patients is because in most cases, we have no clue where the pain is actually coming from. Of course we have ideas. But, for example, with low back pain patients, nobody can actually tell them where the pain fiber nociceptors are actually excited. 

But with pain models, we can start to understand the small blocks of the pain system. We can get a lot of information and the triggers then translate that back to some of the animal work and understand what’s happening in the animals when we do more or less the same thing. That leads to understanding some of the mechanisms which may be taking place in humans. 

How do pain models benefit patients and the general public?

For years and years we've been focused primarily on pain intensity, or how to get rid of pain. But patients are looking for function, how to live with pain. So from a research and clinical perspective, we are looking into the personalized pain management approach to come up with new biomarkers to subgroup patients and direct treatment so we can say, ‘this is better for you than this treatment.’ 

What are some exciting new developments you are working on?

Right now we are trying to use our models to understand changes in the brain. For example, low intensity electrical stimulation of the brain, not high intensity, not something you feel. We use transcranial direct current stimulation, or magnetic stimulation, to stimulate specific parts in the brain to modulate neuronal activity. When we can demonstrate that in our models, we can manipulate these mechanisms and start to modulate pain. We are always looking for new treatment modalities, new medicine. But to do that, we need to understand mechanisms.