Does Approach Matter? Pain,Plane,and Efficacy in Dorsal Versus Volar Trigger Finger Injections—A Discussion

The scoping review by Nasser et al addresses the underexplored but clinically relevant question of whether a dorsal approach to corticosteroid injection (CSI) for trigger finger offers advantages over the traditional volar technique. ¹ This raises a few other interesting questions, namely, does the plane of steroid delivery (intrasheath or subcutaneous) impact efficacy? How much are patient VAS pain scores related to injection technique versus local anesthetic use? Overall, the authors present a clear synthesis of the current evidence and appropriately frame their conclusion that dorsal injection is Non-inferior with caution.

Does the Plane of Steroid Delivery (Intrasheath or Subcutaneous) Impact Efficacy?

The heterogeneity in injection planes (subcutaneous vs intrasheath) in symptom resolution is not to be taken for granted. The current review supports the finding that dorsal CSI has comparable efficacy (symptom resolution 54%-73.5%) and no reported complications relative to volar injection.¹ This is consistent with the broader CSI literature and supports the authors’ conclusion of non-inferiority. The authors insightfully mention that publication bias in other dorsal injection CSI papers (ie, inferior outcome for dorsal injection) may lead to an overinflated success rate in the literature, however.

How Much are Patient VAS Pain Scores Related to Injection Technique Versus Local Anesthetic use?

An important clinical implication discussed is the potential reduction in injection-associated pain with the dorsal approach. While 2 studies suggest lower or equivalent pain scores compared to volar injections, these findings may be confounded by differences in anesthetic use. Interestingly, one of the included studies ² did not use local anesthetic and had higher postinjection VAS pain scores² . The only other study to directly compare dorsal versus volar approach ³ noted improved VAS pain scores in the dorsal approach when using local anesthetic in both approaches. As noted in the reviewers’ comments, clarification regarding injection technique—particularly whether injections were subcutaneous or intrasheath—is essential, as this may influence both pain outcomes. In other words, is intrasheath local-steroid delivery any different than subcutaneous local-steroid delivery when measuring VAS pain scores? The 2 included studies with subcutaneous injection have the lowest VAS pain scores. This raises another question: Do patients have improved VAS pain scores with a “ring block” anesthetic distribution due to subcutaneous delivery? The absence of data on anesthetic distribution represents a notable gap, especially given that patient experience is a central rationale for exploring the dorsal approach.

A key strength of this article lies in its structured methodology, including adherence to PRISMA-ScR and use of Joanna Briggs Institute tools for quality appraisal. However, the small number of included studies (n = 4), with only one randomized controlled trial, significantly limits the strength of its conclusions; the predominance of observational designs introduces inherent risks of bias and confounding, which is mentioned by the authors.

This article provides a useful synthesis of the few studies looking at dorsal CSI versus volar CSI for trigger fingers. It raises other interesting questions as detailed above, and appropriately calls for higher-quality comparative trials.