Treatment of carpal tunnel syndrome by low-level laser therapy versus corticosteroid injection: a randomized, prospective clinical study

To compare the effects of low level laser therapy (LLLT) and corticosteroid injection in patients with moderate carpal tunnel syndrome (CTS). Eighty-seven patients (143 wrists) with moderate CTS were randomized to the corticosteroid or LLLT groups. 40 mg of triamcinolone acetate solution was applied to carpal tunnel of 44 patients (74 wrist). LLLT was applied to 43 patients (70 wrist) five times a week, for a total of 15 sessions (fluence of 6 j/cm² for 1 min per point at a wavelength of 830 nm). Outcome measures were numbness and pain, QuickDASH questionnaire, grasping tests, Tinel and Phalen tests, electrophysiological tests and MRI evaluations, which were tested at the baseline and 1st and 6th months after the treatment. Eighty patients (133 wrists) completed the study at the end of 6 months. VAS and Quick DASH scores were better in the corticosteroid group in the 1st month, but there were no significant differences between groups in the 6th month. Phalen and Tinel tests, strength tests, and motor distal latency improved significantly and similarly in both groups at the 1st and 6th months. Sensory distal latency and sensory nerve conduction velocity showed significant improvements in the 1st and 6th months only in the corticosteroid group. In both groups, median nerve intensity rate and palmary spring rate improved significantly after the treatment. Based on this study, corticosteroid injection and LLLT groups showed statistically significant difference at the 1st month (short-term), whereas there was no significant difference at the 6th month (intermediate-term).