Abstract
AIM: The aim of this study was to investigate the prevalence and associated factors of neuropathic pain (NeP) in patients with refractory arthralgia and to evaluate the role of musculoskeletal ultrasound (MSKUS) in its assessment. MATERIALS AND METHODS: A cross-sectional study was conducted in 187 patients with refractory arthralgia who underwent MSKUS to assess inflammation and NeP using the PainDETECT Questionnaire (PDQ). Clinical data, including demographics, disease activity, and functional status, were collected. The associations between NeP and clinical indicators, as well as MSKUS findings, were analyzed. RESULTS: A total of 187 patients were enrolled, of whom 41 (21.9%) were diagnosed with NeP. The strongest associated factors of pain in the overall cohort were PDQ score (p<0.001) and patient global assessment (PGA) (p<0.001). No significant correlation was found between pain and inflammatory findings on MSKUS. For the prediction of NeP, the numeric rating scale (NRS) score was the only significant associated factor (p<0.001, odds ratio (OR)=1.37, 95% confidence interval (CI): 1.17-1.60), whereas inflammation detected on MSKUS was not associated with NeP (p=0.19, OR=0.80, 95% CI: 0.57-1.12). Analysis of the PDQ components showed that burning pain severity was significantly higher in the moderate/high (M/H) inflammation group compared to the none/low (N/L) inflammation group (Mann-Whitney U test, p=0.032; logistic regression analysis, p=0.01, OR=1.53, 95% CI: 1.1-2.1). Correlations between NRS and NeP were significant in both the N/L (Spearman's ρ=0.516, p<0.001; R²=0.2717, p<0.001) and M/H (Spearman's ρ=0.397, p<0.001; R²=0.1534, p<0.001) groups for all patients. However, within the rheumatoid arthritis (RA) subgroup, a significant correlation between NRS and NeP was observed only in the M/H group (Spearman's ρ=0.431, p=0.002; R²=0.212, p<0.001) but not in the N/L group (Spearman's ρ=0.251, p=0.3; R²=0.03849, p=0.4208). CONCLUSION: NeP was most strongly associated with NRS and MSKUS. Inflammation may change the quality of pain rather than the intensity.