Ultrasound-Guided Hyaluronic Acid Injections for Trigger Finger: A Double-Blinded, Randomized Controlled Trial

Objectives To investigate the effects of ultrasound-guided injections of hyaluronic acid (HA) versus steroid for trigger fingers in adults. Design Prospective, double-blinded, randomized controlled study. Setting Tertiary care center. Participants Subjects with a diagnosis of trigger finger (N=36; 39 affected digits) received treatment and were evaluated. Interventions Subjects were randomly assigned to HA and steroid injection groups. Both study medications were injected separately via ultrasound guidance with 1 injection. Main Outcome Measures The classification of trigger grading, pain, functional disability, and patient satisfaction were evaluated before the injection and 3 weeks and 3 months after the injection. Results At 3 months, 12 patients (66.7%) in the HA group and 17 patients (89.5%) in the steroid group exhibited no triggering of the affected fingers (P=.124). The treatment results at 3 weeks and 3 months showed similar changes in the Quinnell scale (P=.057 and.931, respectively). A statistically significant interaction effect between group and time was found for visual analog scale (VAS) and Michigan Hand Outcome Questionnaire (MHQ) evaluation (P<.05). The steroid group had a lower VAS at 3 months after injection (steroid 0.5±1.1 vs HA 2.7±2.4; P<.001). The HA group demonstrated continuing significant improvement in MHQ at 3 months (change from 3wk: steroid -2.6±14.1 vs HA 19.1±37.0; P=.023; d=.78). Conclusions Ultrasound-guided injection of HA demonstrated promising results for the treatment of trigger fingers. The optimal frequency, dosage, and molecular weight of HA injections for trigger fingers deserve further investigation for future clinical applications.