Ankle pathologies in patients with inflammatory rheumatic diseases: a clinical and ultrasonographic study.

AIM: We determined ankle pathologies in patients with different types of inflammatory rheumatic diseases using high-resolution ultrasonographic (US) images, and compared the findings among the different patient groups.

METHODS: The study included 142 randomly selected inflammatory rheumatic disease patients with clinically swollen or painful ankle joints; 69 patients had rheumatoid arthritis (RA), 58 had spondyloarthropathies (SpA) and 15 had gout. Ankle assessment on US included all of the important anatomical structures. The foot function of patients was evaluated using the Foot Function Index (FFI).

RESULTS: Among all the patients, 98.6% of joints were tender and 72.9% were swollen; 82.1% joints were pathological on US. Tibiotalar joint synovitis was observed significantly more frequently in the SpA and gout patients (P < 0.05). Tibialis posterior (TP) tenosynovitis was significantly more common in the RA group than in the other groups (P < 0.001). Subtalar and talonavicular joint synovitis were observed more frequently in the early RA group compared to the other groups (P < 0.05). Tibiotalar joint synovitis was observed more frequently > 1 year after RA diagnosis (P < 0.05). Subtalar joint synovitis, TP tenosynovitis, and peroneus tenosynovitis were the best predictors of higher FFI scores in patients with RA (R2 c = 0.360, F = 11.83, P < 0.000).

CONCLUSION: Tendon involvement in our RA patients was observed more frequently than has been previously estimated. TP tenosynovitis appears to be more specific for RA, while Achilles tendinitis is more frequent in axial SpA and reactive arthritis. Tibiotalar joint involvement exhibits a time-dependent significant increase in frequency in patients with RA.