This study aimed to evaluate the efficacy and safety of ultrasound-guided needle knife release in the treatment of stenosing tenosynovitis of the flexor pollicis longus.

In this prospective trial, 60 patients with clinically and ultrasonographically confirmed stenosing tenosynovitis of the flexor pollicis longus were randomly allocated to 1 of 3 groups: ultrasound-guided needle knife release (n = 20), traditional conservative treatment (n = 20), and open surgery (n = 20). The primary outcome measure was the Quinnell grade of triggering severity. Secondary outcomes comprised pain intensity (on visual analog scale), satisfaction (5-point Likert scale), and complications. Outcomes were evaluated at baseline, 1 week, 1 month and 3 months post-intervention by blinded assessors.

At all follow-up time points, the needle knife release group demonstrated significantly lower Quinnell grades (p < 0.05) and pain scores (p < 0.001) than the conservative treatment group; satisfaction was greater in the needle knife release group compared to the conservative treatment group at 1 month (p = 0.002) and 3 months (p < 0.001). There were no significant differences in outcomes between the needle knife release group and the open surgery group. The overall complications rate was 5% in the needle knife release group, 10% in the conservative treatment group, and 15% in the open surgery group (p = 0.574).

Ultrasound-guided needle knife release is an effective and safe treatment for stenosing tenosynovitis of the flexor pollicis longus, with outcomes that are better than with traditional conservative treatment and similar to those of open surgery.