A linear model analysis of pain sensitisation in knee osteoarthritis assessed by MRI in relation to the blood biomarker thrombospondin-4

We investigated how pain in knee osteoarthritis (OA) relates to physical damage, clinical parameters, pain sensitisation and serum levels of thrombosponin-4 (TSP4). Across all patients (mild and advanced OA), the number of osteophytes (nOst) and TSP4 levels are significant factors in determining pain levels, with BMI and HADS the strongest factors. Grouping the patients according to low and high TSP4 levels, suggests a TSP4 phenotype that relates to central sensitisation. For high TSP4, pain pressure thresholds are a significant factor in reported knee pain in addition to HADS, BMI and physical damage.