Seventy patients with De Quervain’s tenosynovitis were randomized to receive either a transverse skin incision (n=35) or a longitudinal skin incision (n=35) during open release surgery of the first extensor compartment. The primary outcome was postoperative functional improvement measured by the Thai Patient-Rated Wrist Evaluation (PRWE) score. Secondary outcomes included scar assessment using the Patient and Observer Scar Assessment Scale (POSAS), pain intensity via the verbal numerical rating scale (VNRS), and surgical complications. Outcomes were assessed at 2, 6, and 12 weeks postoperatively. Overall, both groups showed significant improvements in functional outcomes and pain reduction. The longitudinal incision group demonstrated earlier pain relief at 2 and 6 weeks, while scar characteristics were more favorable in the transverse incision group at the same time points. By 12 weeks, differences in pain, function, and scar appearance were no longer significant. These findings suggest that both techniques are equally effective, with the choice of incision depending on individual patient and surgeon preferences.