Ultrasound Features and Therapeutic Monitoring of Pachydermodactyly

Pachydermodactyly is a rare and benign acquired digital fibromatosis that can clinically mimic inflammatory arthropathies. We present a case series of three adolescents in whom high-frequency cutaneous ultrasound was essential for the diagnosis, revealing homogeneous, hypoechoic, and non-compressible dermal thickening around the proximal interphalangeal joints without evidence of synovitis, tendon involvement, or bone erosions. Ultrasound also enabled objective monitoring of treatment response following intralesional corticosteroid injections in two cases. Cutaneous ultrasound represents a valuable, non-invasive tool for both the diagnosis and follow-up of pachydermodactyly, avoiding unnecessary invasive procedures.