Predominant ultrasonographic extracapsular changes in symptomatic psoriatic dactylitis: results from a multicenter cross-sectional study comparing symptomatic and asymptomatic hand dactylitis.

Digital tenderness and pain are linked to US tenosynovitis of grade > 2 and extra synovial abnormalities and conversely asymptomatic dactylitis is associated with joint-based synovitis.Key Points• Digital tenderness and local pain in psoriatic arthritis dactylitis are strongly associated with flexor tenosynovitis of grade> 2, soft tissue edema, and subcutaneous PD signal.• In psoriatic arthritis, asymptomatic dactylitis showed a greater prevalence of joint synovitis than symptomatic dactylitis.• In psoriatic arthritis, ultrasound inflammatory abnormalities are present in about 70% of cold dactylitis which is linked for disease chronicity.• In psoriatic arthritis, the flexor tendon and adjacent soft tissues play a significant role in symptomatic dactylitis.