In finger osteoarthritis, change in synovitis is associated with change in pain on a joint-level; a longitudinal magnetic resonance imaging study

Abstract

Objective: To investigate determinants of decrease and increase in joint pain in symptomatic finger osteoarthritis (OA) on magnetic resonance (MR) imaging over 2 years. Design: Eighty-five patients (81.2% women, mean age 59.2 years) with primary hand OA (89.4% fulfilling American College of Rheumatology (ACR) classification criteria) from a rheumatology outpatient clinic received contrast-enhanced MR imaging (1.5T) and physical examination of the right interphalangeal finger joints 2e5 at baseline and at follow-up 2 years later. MR images were scored paired in unknown time order, following the Hand OA MRI scoring system (HOAMRIS). Joint pain upon palpation was assessed by research nurses. Odds ratios (ORs; 95% confidence intervals) were estimated on joint level (n ¼ 680), using generalized estimating equations (GEE) to account for the within patient effects. Additional adjustments were made for change in MR-defined osteophytes, synovitis, and bone marrow lesions (BMLs). Results: Of 116 painful joints at baseline, at follow-up: 76 had less pain, 21 less synovitis, and 13 less BMLs. A decrease in synovitis (OR ¼ 5.9; 1.12e31.0), but not in BMLs (OR ¼ 0.39; 0.10e1.50), was associated with less pain. Of 678 joints without maximum baseline pain, at follow-up: 115 had increased pain, 132 increased synovitis, 96 increased BMLs, and 44 increased osteophytes. Increased synovitis (OR ¼ 1.81; 1.11e2.94), osteophytes (OR ¼ 2.75; 1.59e4.8), but not BMLs (OR ¼ 1.14; 0.81e1.60), was associated with increased pain. Through stratification it became apparent that BMLs were mainly acting as effect modifier of the synovitisepain association. Conclusion: Decrease in MR-defined synovitis is associated with reduced joint pain, identifying synovitis as a possible target for treatment of finger OA.

Two‐Year Changes in Magnetic Resonance Imaging Features and Pain in Thumb Base Osteoarthritis

“…Few studies have investigated the longitudinal relationship between inflammatory MRI features and pain in hand OA. Previous studies have shown that in interphalangeal OA, an increase in synovitis was associated with more pain, less synovitis was associated with less pain, and also that fluctuation in BMLs amplified this effect of synovitis on change in pain (9,10). These studies also suggest that BMLs mainly have an additive effect when accompanying synovitis, and that synovitis is the main driver of pain (6,10).…”

“…Previous studies have shown that in interphalangeal OA, an increase in synovitis was associated with more pain, less synovitis was associated with less pain, and also that fluctuation in BMLs amplified this effect of synovitis on change in pain (9,10). These studies also suggest that BMLs mainly have an additive effect when accompanying synovitis, and that synovitis is the main driver of pain (6,10). Our study shows that a longitudinal association between inflammatory MRI features and pain on palpation is also present in thumb base OA.…”

“…Longitudinal imaging studies of interphalangeal OA have shown that a change in MRI inflammation was also associated with a change in pain levels ( 9 , 10 ). In thumb base OA, however, no longitudinal imaging studies have been performed thus far.…”

Effusion attenuates the effect of synovitis on radiographic progression in patients with hand osteoarthritis: a longitudinal magnetic resonance imaging study

“…Fourth, we did not ascertain effusion during follow-up while it is possible that effusion is a transient phenomenon [ 3 , 18 ]. However, several studies have shown that baseline inflammatory features such as synovitis and BMLs are of clinical relevance for their association with pain and structural progression [ 3 , 5 , 6 , 19 ], regardless of their possible transient nature [ 20 ]. We think the same applies to effusion and therefore, our results are relevant.…”

“…We envision including effusion in the MRI scoring system; our scoring method could serve as a blueprint for this. From an earlier MRI study, we learned that increase/decrease in synovitis was associated with increase/decrease in pain [ 20 ]. We think that especially this last finding is interesting because the association of a decrease in synovitis with a decrease in joint pain makes synovitis a treatment target.…”