Comparison of Landmark-Based Versus Transverse Carpal Ligament Penetrating Corticosteroid Injection for Bilateral Carpal Tunnel Syndrome: A Prospective Randomized Trial.

Background: This study aimed to compare the effectiveness and complications between classic palmaris longus tendon landmark-based corticosteroid injection (CI) and transverse carpal ligament (TCL)-penetrating CI for carpal tunnel syndrome (CTS).

Methods: We performed a landmark-based CI on one hand and a TCL-penetrating CI on the other side after randomization in 30 consecutive patients with bilateral CTS. The pain visual analog scale (VAS) and the Boston Carpal Tunnel Questionnaire (BCTQ) were assessed at baseline, 4 weeks, and 3 and 6 months after injection. Skin hypopigmentation of the injection site was evaluated using the modified Vancouver scar scale (mVSS). Pain during needle insertion was evaluated using a VAS for each hand.

Results: The mean patient age was 56 ± 11 years (range, 32-77 years), and 27 patients (90.0%) were women. The pain VAS, BCTQ scores, and the incidence of skin hypopigmentation were not significantly different between the 2 groups after injection, but the mean mVSS scores were significantly higher in the landmark-based CI group at all time points. The pain VAS score during needle insertion was significantly higher in the TCL-penetrating CI group.

Conclusions: When comparing the pain VAS and BCTQ scores, the difference between the 2 groups was not statistically significant. TCL-penetrating CI causes considerable pain during needle insertion but causes less severe skin hypopigmentation than landmark-based CI in CTS treatment.