Non-surgical local treatments of digital ulcers in systemic sclerosis: a systematic literature review

Introduction: Digital ulcers (DUs) are difficult to treat in patients with systemic sclerosis (SSc) and systemic (i.e., pharmacological) therapy is currently considered the ‘standard of care’. Our aim was to examine the safety and efficacy of local, non-surgical treatment for SSc-DUs. Methods: A systematic literature review (SLR) of original research articles up to August, 29 2022 was performed according to the PICO framework. References were independently screened by two reviewers and risk of bias was assed using validated tools. Due to study heterogeneity narrative summaries are used to present data. Results: Among 899 retrieved references, 14 articles were included (2 randomised trials (RTs), and 12 observational (OBS) studies). The most frequently studied procedure (5 studies) was botulin A toxin (hand or single finger) injection with a reported healing rate (HR) of 71%-100%. Amniotic and hydrocolloid membranes were examined in one study each and associated with a good HR. Tadalafil 2% cream was studied in a single study with a reduction in the number of DUs. Vitamin E gel was associated with a reduction in ulcer healing time. Low-level light therapy, hydrodissection and corticosteroid injection, extracorporeal shock wave (ESW) and photobiomodulation were evaluated in a single study each and showed a positive trend. Dimethyl sulfoxide was associated with significant local toxicity. Conclusions: A range of non-surgical, local treatments for SSc-DUs have been explored and showed efficacy to some extent. We have identified methodological flaws that should be avoided in the design of future studies to explore locally-acting treatments for SSc-DUs.