A randomized comparative trial: Relative motion vs metacarpophalangeal joint blocking orthoses for trigger finger management.

Background: Metacarpophalangeal joint blocking orthoses are used for managing trigger finger, with limited intervention evidence for relative motion orthoses.

Purpose: This 6-week trial evaluated the effectiveness of metacarpophalangeal joint blocking and relative motion orthoses for managing trigger finger severity, function, occupational performance/satisfaction, and orthosis wearability.

Study Design: Randomized comparative trial, ClinicalTrials.gov (NCT05763017).

Methods: Thirty-six participants with no prior trigger finger intervention and ≥ 21 years old were randomly assigned to the relative motion or metacarpophalangeal joint blocking orthosis (neutral metacarpophalangeal joint) groups. The primary author screened for eligibility and fabricated the orthoses. Week-1 and week-6 Therapist A assessed stages of stenosing tenosynovitis, number of triggering events in 10 active fists (NTE), visual analog scales for pain, orthosis comfort and satisfaction (wearability), Disabilities of the Arm, Shoulder and Hand, and Canadian Occupational Performance Measure. Week-3 Therapist B administered orthosis wearability visual analog scales. The relative motion pencil test determined orthosis design, relative motion extension or flexion, and metacarpophalangeal joint differential. Mixed-effects ANOVA was used to compare week-1 and week-6 outcomes. Cohen's f was used to measure the effect size.

Results: Thirty-five participants completed this trial. Between week-1 and week-6, both groups demonstrated significant differences with large effect size in stages of stenosing tenosynovitis (f=1.21), NTE (f=1.07), pain at rest (f=0.36), pain during activity (f=0.76), Disabilities of the Arm, Shoulder and Hand (f=1.19), Canadian Occupational Performance Measure performance (f=1.12) and satisfaction (f=1.14). No superior effect was noted between orthosis groups. Wearability for both groups was 7/10 at rest and 4/10 during activity. The pencil test yielded 15/18 relative motion extension orthoses and 20-25˚ metacarpophalangeal differential.

Conclusions: Symptom severity, pain, hand function, and orthosis wearability outcomes support interchangeable use of relative motion and metacarpophalangeal joint blocking orthoses for managing trigger finger.