To assess the relationship between clinically detected swelling and effusion diagnosed by ultrasonography (US) in metatarsophalangeal (MTP) and talocrural (TC) joints in patients with rheumatoid arthritis (RA).
Thirty consecutive patients with RA were studied. Altogether 288 MTP joints and 60 TC joints were evaluated. The clinical investigations were carried out by one doctor and the US investigations by another and they were blinded to each others' results.
The clinical examination and US gave similar results in 194 MTP joints, whereas they differed in the remaining 94 MTP joints, and correspondingly the results were similar in 34 TC joints and differed in 26 TC joints. The kappa coefficient between these investigations was 0.165 in MTP joints and 0.043 in TC joints, showing very poor agreement.
These preliminary results showed poor agreement between the clinical assessment of swelling and effusion detected by US in MTP and TC joints. Thus US may considerably improve the diagnosis of synovitis in patients with RA.