Self-reported knee pain and disability among healthy individuals: reference data and factors associated with the Knee injury and Osteoarthritis Outcome Score (KOOS) and KOOS-Child

et al. 2019

Preprint

Background: Inflammatory mediators in the synovial fluid (SF) play critical roles in the initiation and development of pain in knee osteoarthritis (KOA). However, data for inflammatory marker expression are conflicting, and the role of SF inflammatory mediators in neuropathic pain is not clear. Therefore, the aim of this study was to identify SF inflammatory mediators associated with nociceptive and neuropathic pain in KOA. Methods: Levels of IL-1β, IL-6, TNF-α, macrophage colony-stimulating factor, MMP-3, MMP-13, metalloproteinase with thrombospondin motifs 5, calcitonin gene-related peptide, neuropeptide Y, substance P and bradykinin were measured using enzyme-linked immunosorbent assays in 86 patients. Nociceptive pain was assessed using the numeric rating scale (NRS), visual analog scale (VAS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score. Neuropathic pain was determined using the PainDETECT questionnaire. Moreover, knee function was evaluated by the WOMAC score and range of motion (ROM) assessments. Radiological grade was defined using the Kellgren-Lawrence (K-L) grading scale. Results: Pain scores measured using different methods correlated highly with each other. A worse K-L grade and knee function were associated with worse pain. Expression of IL-1β and IL-6 was increased in the early stage compared with the late stage. The NRS score correlated positively with age, K-L grade, and the WOMAC score and negatively with ROM and TNF-α expression. The VAS correlated positively with age, K-L grade, and the WOMAC score but negatively with ROM and levels of IL-1β, IL-6 and TNF-α. The WOMAC pain score did not correlate with any of the inflammatory mediators measured; it correlated only with ROM. The PainDETECT score correlated only with the WOMAC score. Expression of other inflammatory mediators did not correlate with any of the pain scores. Conclusions: IL-1β, IL-6 and TNF-α play critical roles in pain in the early stage of KOA and correlate with pain. The catabolic enzymes and neuropeptides measured do not correlate with nociceptive and neuropathic pain. New biomarkers related to pain in the late stage need to be further investigated.

Section: Discussionsupporting

confidence: 93%

Profiling of inflammatory mediators in the synovial fluid related to pain in knee osteoarthritis

et al. 2019

Preprint

“…Numerous studies have demonstrated that pain affects ROM (36,37). In agreement with previous reports, our study demonstrated that patient ROM was highly correlated with pain scores (r=-0.403~-0.451, p<0.000).…”

Section: Discussionsupporting

confidence: 92%

“…Patient characteristics are correlated to pain in OA (30). First, old age is thought to be a systemic risk factor for OA (34,35) and is correlated to pain (36). In our study, we found that age was significantly correlated to pain scores (r=0.430-0.474, p<0.000) and played an important role in the genesis of OA.…”

Section: Discussionsupporting

confidence: 49%

Profiling of inflammatory mediators in the synovial fluid related to pain in knee osteoarthritis

et al. 2019

Preprint

Background: Inflammatory mediators in the synovial fluid (SF) play critical roles in the initiation and development of pain in knee osteoarthritis (KOA). However, the expression of inflammatory mediators is controversial and the role of SF inflammatory mediators in neuropathic pain is not clear. Therefore, the aim of this study is to identify the SF inflammatory mediators associated with nociceptive and neuropathic pain in KOA. Methods: The levels of IL-1β, IL-6, TNF-α, macrophage colony-stimulating factor, MMP-3, MMP-13, metalloproteinase with thrombospondin motifs 5, calcitonin gene-related peptide, neuropeptide Y, substance P and bradykinin were measured in 86 patients using enzyme-linked immunosorbent assays. Nociceptive pain was measured using the numeric rating scale (NRS), visual analog scale (VAS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score. Neuropathic pain was measured using the PainDETECT questionnaire. Moreover, knee function was evaluated by the WOMAC score and range of motion (ROM) assessments. Radiological grade was defined using the Kellgren-Lawrence (K-L) grading scale. Results: Pain scores measured using different methods were highly correlated to each other. The worse the pain, the worse the K-L grade and knee function were. The expression of IL-1β and IL-6 was increased in the early stage compared with the late stage. The NRS was positively correlated to age, K-L grade, and the WOMAC score and negatively correlated to ROM and TNF-α expression. The VAS was positively correlated to age, K-L grade, and the WOMAC score but negatively correlated to ROM and the levels of IL-1β, IL-6 and TNF-α. The WOMAC pain score was not correlated to any of the measured inflammatory mediators; it correlated to only ROM. The PainDETECT score correlated to only the WOMAC score. The expression of other inflammatory mediators was not correlated to any of the pain scores. Conclusions: IL-1β, IL-6 and TNF-α play critical roles in pain in the early stage of KOA and correlated to pain. The measured catabolic enzymes and neuropeptides are not correlated to nociceptive and neuropathic pain. New biomarkers related to pain in the late stage need to be further investigated.

“…Second, radiological images are important tools for the evaluation of OA severity and predicts knee pain. The positive correlation between knee pain and K-L grade was found in several studies (37,38 Numerous studies have demonstrated that pain affects ROM (36,37). In agreement with previous reports, our study demonstrated that patient ROM was highly correlated with pain scores (r=-0.403~-0.451, p<0.000).…”

Section: Discussionsupporting

confidence: 91%

Profiling of inflammatory mediators in the synovial fluid related to pain in knee osteoarthritis

et al. 2019

Preprint

Background: Inflammatory mediators in the synovial fluid (SF) play critical roles in the initiation and development of pain in knee osteoarthritis (KOA). However, the expression of inflammatory mediators is controversial and the role of SF inflammatory mediators in neuropathic pain is not clear. Therefore, the aim of this study is to identify the SF inflammatory mediators associated with nociceptive and neuropathic pain in KOA. Methods: The levels of IL-1β, IL-6, TNF-α, macrophage colony-stimulating factor, MMP-3, MMP-13, metalloproteinase with thrombospondin motifs 5, calcitonin gene-related peptide, neuropeptide Y, substance P and bradykinin were measured in 86 patients using enzyme-linked immunosorbent assays. Nociceptive pain was measured using the numeric rating scale (NRS), visual analog scale (VAS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC ) pain score. Neuropathic pain was measured using the PainDETECT questionnaire. Moreover, knee function was evaluated by the WOMAC score and range of motion (ROM) assessments. Radiological grade was defined using the Kellgren-Lawrence (K-L) grading scale. Results: Pain scores measured using different methods were highly correlated to each other. The worse the pain, the worse the K-L grade and knee function were. The expression of IL-1β and IL-6 was increased in the early stage compared with the late stage. The NRS was positively correlated to age, K-L grade, and the WOMAC score and negatively correlated to ROM and TNF-α expression. The VAS was positively correlated to age, K-L grade, and the WOMAC score but negatively correlated to ROM and the levels of IL-1β, IL-6 and TNF-α. The WOMAC pain score was not correlated to any of the measured inflammatory mediators; it correlated to only ROM. The PainDETECT score correlated to only the WOMAC score. The expression of other inflammatory mediators was not correlated to any of the pain scores. Conclusions: IL-1β, IL-6 and TNF-α exhibit higher expression in early stage of KOA than the late stage of KOA and correlated to pain. The measured catabolic enzymes and neuropeptides are not correlated to nociceptive and neuropathic pain. New biomarkers related to pain in the late stage need to be further investigated.