Correlation of anxiety and chronic pain to grade of synovitis in patients with knee osteoarthritis.

Background: This study was conducted with the objective of finding out the correlation between synovial inflammation measured histopathologically and subjective symptoms; anxiety and chronic pain, in knee osteoarthritis (OA). Subjects and methods: Thirty patients were included in the study. Ten of them were in a control group with meniscal injury, ten had early OA and 10 had late OA. Knee radiographs were graded using Kellgren-Lawrence classification. Synovial biopsies were taken during surgery or arthroscopy and synovitis score was measured by Krenns method. Anxiety was measured with Beck Anxiety Inventory and pain was taken as part of the WOMAC score (The Western Ontario and McMaster Universities Arthritis Index). Results: Krenn synovitis score was determined as: no synovitis, low-grade synovitis and high-grade synovitis. Group with low grade synovitis had significantly higher pain score than high-grade synovitis group (p=0.011). No-synovitis group had significantly lower Beck Anxiety Inventory than low-grade synovitis group (p=0.014) and high-grade synovitis (p=0.008). There are no significant differences between low-grade synovitis and high-grade synovitis in anxiety score (p=0.912). Conclusions: Chronic pain is more present in late osteoarthritis, when synovitis is less pronounced. Anxiety affects patients who suffer osteoarthritis, but it is statistically the same regarding synovitis grade, i.e. whether it is early or late osteoarthritis.