Approximately one-quarter of patients with clinically suspect arthralgia (CSA) have intermetatarsal bursitis (IMB), which is often accompanied by subclinical synovitis and tenosynovitis, according to a study published in Rheumatology. Researchers performed a large MRI study to assess the occurrence and prognostic value of IMB in 577 patients with CSA. Participants underwent contrast-enhanced MRI of the forefoot, metacarpophalangeal joints, and wrist; MRIs were assessed for subclinical synovitis/tenosynovitis/osteitis and IMB. The association between IMB and other MRI-detected subclinical inflammation was also examined. Results showed that 23% of participants had IMB at presentation with CSA. In anti-citrullinated protein antibody (ACPA)-positive versus AC-PA-negative CSA, IMB was more frequent (47% vs 19%). The likelihood of subclinical synovitis and tenosynovitis was increased for patients with IMB (ORs, 3.4 and 5.9, respectively). The risk of developing arthritis was increased with IMB (HR, 1.6) after adjustment for other subclinical inflammation. In ACPA-positive, but not ACPA-negative, patients with CSA, IMB presence predicted arthritis development (adjusted HR, 2.2).
