Thirty patients with bilateral carpal tunnel syndrome were randomized to receive a landmark-based corticosteroid injection on one hand and a TCL-penetrating injection on the other. The primary outcome was the symptom domain score of the Boston Carpal Tunnel Questionnaire (BCTQ-S) at 3 months. Secondary outcomes included pain VAS scores, function domain of BCTQ (BCTQ-F), pain during needle insertion, and degree of skin hypopigmentation measured by the modified Vancouver Scar Scale (mVSS). Outcomes were assessed at baseline, 4 weeks, 3 months, and 6 months. Overall, the study found no significant differences in pain or functional scores between techniques, though the TCL-penetrating approach resulted in significantly less skin hypopigmentation at all time points but caused greater immediate procedural pain. These findings suggest both techniques are clinically effective, but TCL-penetrating injections may be preferred to reduce cosmetic complications.