About 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. Bastiaan T. van Dijk, Ph.D. candidate, and colleagues 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 for IMB. The association between IMB and other MRI-detected subclinical inflammation was assessed. Among participants, 23% had IMB at presentation with CSA. In anti-citrullinated protein antibody (ACPA)-positive versus ACPAnegative 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), as was the risk for developing arthritis 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).
