In systemic sclerosis, few studies have shown that hand and wrist ultrasound is more sensitive than clinical examination in the detection of synovitis and tenosynovitis. Even fewer studies have investigated ankle and foot involvement with ultrasound. Our objectives were to investigate ultrasound prevalence of wrist, hand, ankle and foot synovitis and tenosynovitis in patients with systemic sclerosis classified with ACR/EULAR 2013 criteria, and to study their relationship with disease features and hand disability.

Consecutive patients with systemic sclerosis, classified with ACR/EULAR 2013 criteria, were included in a monocentric cross-sectional study. They underwent standardized musculoskeletal clinical examination and hand, wrist, ankle and foot ultrasound. Clinical, biological and imaging data were also collected.

Fifty-five patients were included. Ultrasound was more sensitive than clinical examination to detect at least one synovitis (respectively 52% versus 25%, P=0.025) and at least one tenosynovitis (respectively 16% versus 4%, P=0.009); 18% of patients had ankle tenosynovitis and 29% had ankle and/or foot synovitis, mostly located at metatarsophalangeal joints (25.5%). Having at least one ultrasound hand synovitis was associated with higher Cochin hand functional disability scale (mean 25±3 versus 12±2, P=0.003) and diffuse cutaneous subset (P=0.038).

Our study shows that ultrasound is more sensitive than clinical examination to detect synovitis and tenosynovitis in systemic sclerosis. The foot involvement is less frequent than hand involvement, mainly localized at metatarsophalangeal joint. Finally, having at least one synovitis of the hand is associated with diffuse cutaneous subset and higher hand disability.