Extracorporeal Shock Wave Therapy for Digital Ulcers of Systemic Sclerosis: A Phase 2 Pilot Study

Patients with systemic sclerosis (SSc) often display Raynaud’s phenomenon and digital skin ulcers. As these ulcers are not associated with autoimmune factors or abnormal coagulation, conventional immunosuppressive therapies, vasodilators, and anticoagulants are often ineffective. Here, we used extracorporeal shock wave therapy (ESWT) to treat these ulcers. Nine SSc patients with new digital ulcers, previously treated with at least one currently available vasodilator or anticoagulant were enrolled. One ESWT session consisted of 100 pulses at 0.08-0.25 mJ/mm2 in 20 areas on both hands and 15 areas on both feet, totaling 7,000 pulses. Treatment was performed once per week for 9 weeks with observations over 20 weeks. Outcomes were evaluated according to the number and diameter of ulcers, Rodnan skin score, Health Assessment Questionnaire (HAQ), EuroQol 5 dimensions (EQ-5D), visual analog scale for pain, and the PainVision system. The surface skin temperature of all the fingers was measured using thermography. Ulcers showed signs of healing after one session, and their mean number decreased from 5.4 to 1.1 at 9 weeks. In particular, of the 18 large ulcers (> 5 mm) observed in 7 patients before the treatment, 10 disappeared and the rest became smaller; namely, the mean size decreased from 10.9 mm to 2.5 mm at 20 weeks. The average scores on the HAQ, EQ-5D, and PainVision system also improved. Treatment was minimally invasive and could be repeated without any adverse effects. ESWT may be added to standard treatments for indolent digital ulcers of SSc, as an effective and safe method.