Definition of neuropathic pain
The International Association for the Study of Pain (IASP) defines neuropathic pain as pain related to an injury or disease affecting the somatosensory system. It therefore does not have the same mechanisms as nociceptive pain.
Involvement of the somatosensory system can occur in an obvious neurological context (pain occurring after shingles, painful diabetic neuropathy, central pain occurring after a stroke, pain occurring after chemotherapy, etc.). It also frequently occurs in a non-neurological context such as post-operative follow-up, surgery (even benign) often being responsible for nerve damage.
It is characterized by pain such as burning or electric shocks with, on clinical examination, hypoesthesia or, on the contrary, allodynia (pain induced by a non-painful stimulus). It is often associated with non-painful sensory signs (paraesthesia, numbness, pruritus). Its detection is facilitated by the use of questionnaires such as the DN4 which is based on the identification of these semiological characteristics.
Screening for neuropathic pain is all the more important since it can co-exist with nociceptive pain in the context of mixed pain. This is particularly the case in lumbo-radiculalgia consisting of low back pain most often with a nociceptive mechanism and radiculalgia with a neuropathic mechanism.
It can come from the periphery: peripheral neuropathy
It can come from the central nervous system: brain and/or spinal cord
It is difficult and relies on drug and non-drug methods described in the chapter: Treatment of neuropathic pain.