In modern society, chronic low back pain is a common disease and is the most common cause of limiting social and economic activities in the population over the age of 45. Unlike general chronic low back pain patients, there may be cases of complaining of non-specific symptoms. However, it is difficult to diagnose or treat neuropathic chronic low back pain patients because they have a more complex pathophysiology than simple low back pain. Neuropathic chronic low back pain is caused by abnormal pain inducing mechanisms due to damage and dysfunction of the nervous system from the peripheral to the brain. Symptoms can occur anywhere in the vertebral or paravertebral structures where nociceptors are distributed. It is difficult to diagnose neuropathic back pain. Early and appropriate treatment can prevent the nervous system from being improperly adapted to become chronic pain syndrome, so it is very important as a clinician to access and diagnose neuropathic pain as easily as possible and apply general treatment early. Therefore, in this review article, based on literatures and research results on chronic low back pain with neuropathic component, we understand diseases and suggest directions for clinical applications.

Purpose
This study examined the utility of PainVision (Nipro, Osaka, Japan) calculating the degree of lower back pain, as compared with conventional pain assessment (Numeric Rating Scale [NRS], McGill Pain Questionnaire [MPQ]).
Materials and Methods
A retrospective study was conducted from March 2021 to July 2021 on 40 patients with low back pain. NRS score, MPQ score and the degree of pain calculated by PainVision were measured before and after facet joint block in each patient. An electrode was patched on opposite side of lower back surface at which the patients complain of pain and the degree of pain was automatically calculated (degree of pain=100×[current producing pain comparable with low back pain–current at perception threshold/current at perception threshold]). Correlations between NRS and MPQ scores and the degree of pain were determined using Spearman’s rank correlation test.
Results
There was a strong correlation between the NRS and MPQ scores at each time point (before: rs=0.67, p<0.0001, after: rs=0.78, p<0.0001). The degree of pain before facet joint block also showed a moderate correlation with NRS and MPQ scores at each time point (NRS: rs=0.60, p<0.0001, MPQ: rs=0.343, p<0.03). The change in the degree of pain after facet joint block showed a moderate correlation with changes in the NRS and MPQ scores (NRS: rs=0.509, p<0.0001, MPQ: rs=0.581, p<0.0001).
Conclusions
The Pain vision can evaluate lower back pain well and quantify it in the form of pain degree, which is helpful for objective quantitative analysis of lower back pain.